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Liu Y, Chen M, Fang J, Xiao L, Liu S, Li Q, Qiu B, Huang R, Zhang J, Peng Y. A novel evaluation model of image registration for cone-beam computed tomography guided lung cancer radiotherapy. Thorac Cancer 2024; 15:1333-1342. [PMID: 38686543 PMCID: PMC11168913 DOI: 10.1111/1759-7714.15320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 04/11/2024] [Accepted: 04/16/2024] [Indexed: 05/02/2024] Open
Abstract
BACKGROUND The aim of the study was to establish a weighted comprehensive evaluation model (WCEM) of image registration for cone-beam computed tomography (CBCT) guided lung cancer radiotherapy that considers the geometric accuracy of gross target volume (GTV) and organs at risk (OARs), and assess the registration accuracy of different image registration methods to provide clinical references. METHODS The planning CT and CBCT images of 20 lung cancer patients were registered using diverse algorithms (bony and grayscale) and regions of interest (target, ipsilateral, and body). We compared the coverage ratio (CR) of the planning target volume (PTVCT) to GTVCBCT, as well as the dice similarity coefficient (DSC) of the GTV and OARs, considering the treatment position across various registration methods. Furthermore, we developed a mathematical model to assess registration results comprehensively. This model was evaluated and validated using CRFs across four automatic registration methods. RESULTS The grayscale registration method, coupled with the registration of the ipsilateral structure, exhibited the highest level of automatic registration accuracy, the DSC were 0.87 ± 0.09 (GTV), 0.71 ± 0.09 (esophagus), 0.74 ± 0.09 (spinal cord), and 0.91 ± 0.05 (heart), respectively. Our proposed WCEM proved to be both practical and effective. The results clearly indicated that the grayscale registration method, when applied to the ipsilateral structure, achieved the highest CRF score. The average CRF scores, excellent rates, good rate and qualification rates were 58 ± 26, 40%, 75%, and 85%, respectively. CONCLUSIONS This study successfully developed a clinically relevant weighted evaluation model for CBCT-guided lung cancer radiotherapy. Validation confirmed the grayscale method's optimal performance in ipsilateral structure registration.
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Affiliation(s)
- Yimei Liu
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Meining Chen
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Jianlan Fang
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Liangjie Xiao
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Songran Liu
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Qiwen Li
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Bo Qiu
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Runda Huang
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Jun Zhang
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Yinglin Peng
- State Key Laboratory of Oncology in South China, Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and Therapy, Department of Radiation Oncology, Guangdong Provincial Clinical Research Center for CancerSun Yat‐sen University Cancer CenterGuangzhouChina
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Huang L, Kurz C, Freislederer P, Manapov F, Corradini S, Niyazi M, Belka C, Landry G, Riboldi M. Simultaneous object detection and segmentation for patient-specific markerless lung tumor tracking in simulated radiographs with deep learning. Med Phys 2024; 51:1957-1973. [PMID: 37683107 DOI: 10.1002/mp.16705] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 04/23/2023] [Accepted: 05/12/2023] [Indexed: 09/10/2023] Open
Abstract
BACKGROUND Real-time tumor tracking is one motion management method to address motion-induced uncertainty. To date, fiducial markers are often required to reliably track lung tumors with X-ray imaging, which carries risks of complications and leads to prolonged treatment time. A markerless tracking approach is thus desirable. Deep learning-based approaches have shown promise for markerless tracking, but systematic evaluation and procedures to investigate applicability in individual cases are missing. Moreover, few efforts have been made to provide bounding box prediction and mask segmentation simultaneously, which could allow either rigid or deformable multi-leaf collimator tracking. PURPOSE The purpose of this study was to implement a deep learning-based markerless lung tumor tracking model exploiting patient-specific training which outputs both a bounding box and a mask segmentation simultaneously. We also aimed to compare the two kinds of predictions and to implement a specific procedure to understand the feasibility of markerless tracking on individual cases. METHODS We first trained a Retina U-Net baseline model on digitally reconstructed radiographs (DRRs) generated from a public dataset containing 875 CT scans and corresponding lung nodule annotations. Afterwards, we used an independent cohort of 97 lung patients to develop a patient-specific refinement procedure. In order to determine the optimal hyperparameters for automatic patient-specific training, we selected 13 patients for validation where the baseline model predicted a bounding box on planning CT (PCT)-DRR with intersection over union (IoU) with the ground-truth higher than 0.7. The final test set contained the remaining 84 patients with varying PCT-DRR IoU. For each testing patient, the baseline model was refined on the PCT-DRR to generate a patient-specific model, which was then tested on a separate 10-phase 4DCT-DRR to mimic the intrafraction motion during treatment. A template matching algorithm served as benchmark model. The testing results were evaluated by four metrics: the center of mass (COM) error and the Dice similarity coefficient (DSC) for segmentation masks, and the center of box (COB) error and the DSC for bounding box detections. Performance was compared to the benchmark model including statistical testing for significance. RESULTS A PCT-DRR IoU value of 0.2 was shown to be the threshold dividing inconsistent (68%) and consistent (100%) success (defined as mean bounding box DSC > 0.6) of PS models on 4DCT-DRRs. Thirty-seven out of the eighty-four testing cases had a PCT-DRR IoU above 0.2. For these 37 cases, the mean COM error was 2.6 mm, the mean segmentation DSC was 0.78, the mean COB error was 2.7 mm, and the mean box DSC was 0.83. Including the validation cases, the model was applicable to 50 out of 97 patients when using the PCT-DRR IoU threshold of 0.2. The inference time per frame was 170 ms. The model outperformed the benchmark model on all metrics, and the comparison was significant (p < 0.001) over the 37 PCT-DRR IoU > 0.2 cases, but not over the undifferentiated 84 testing cases. CONCLUSIONS The implemented patient-specific refinement approach based on a pre-trained baseline model was shown to be applicable to markerless tumor tracking in simulated radiographs for lung cases.
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Affiliation(s)
- Lili Huang
- Department of Radiation Oncology, LMU University Hospital, LMU Munich, Munich, Germany
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, München, Germany
| | - Christopher Kurz
- Department of Radiation Oncology, LMU University Hospital, LMU Munich, Munich, Germany
| | - Philipp Freislederer
- Department of Radiation Oncology, LMU University Hospital, LMU Munich, Munich, Germany
| | - Farkhad Manapov
- Department of Radiation Oncology, LMU University Hospital, LMU Munich, Munich, Germany
| | - Stefanie Corradini
- Department of Radiation Oncology, LMU University Hospital, LMU Munich, Munich, Germany
| | - Maximilian Niyazi
- Department of Radiation Oncology, LMU University Hospital, LMU Munich, Munich, Germany
| | - Claus Belka
- Department of Radiation Oncology, LMU University Hospital, LMU Munich, Munich, Germany
- German Cancer Consortium (DKTK), partner site Munich, a partnership between DKFZ and LMU University Hospital Munich, Germany
- Bavarian Cancer Research Center (BZKF), Munich, Germany
| | - Guillaume Landry
- Department of Radiation Oncology, LMU University Hospital, LMU Munich, Munich, Germany
| | - Marco Riboldi
- Department of Medical Physics, Faculty of Physics, Ludwig-Maximilians-Universität München, München, Germany
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Bleeker M, van der Horst A, Bel A, Sonke JJ, van Hooft JE, Pouw RE, Hulshof MC. Endoscopically placed fiducial markers for image-guided radiotherapy in preoperative gastric cancer: Technical feasibility and potential benefit. Endosc Int Open 2023; 11:E866-E872. [PMID: 37745837 PMCID: PMC10513787 DOI: 10.1055/a-2129-2840] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Accepted: 07/13/2023] [Indexed: 09/26/2023] Open
Abstract
Background and study aims Fiducial markers have demonstrated clinical value in radiotherapy in several organs, but little is known about markers in the stomach. Here, we assess the technical feasibility of endoscopic placement of markers in gastric cancer patients and their potential benefit for image-guided radiotherapy (IGRT). Patients and methods In this prospective feasibility study, 14 gastric cancer patients underwent endoscopy-guided gold (all patients) and liquid (7 patients) marker placements distributed throughout the stomach. Technical feasibility, procedure duration, and potential complications were evaluated. Assessed benefit for IGRT comprised marker visibility on acquired imaging (3-4 computed tomography [CT] scans and 19-25 cone-beam CTs [CBCTs] per patient) and lack of migration. Marker visibility was compared per marker type and location (gastroesophageal junction (i.e., junction/cardia), corpus (corpus/antrum/fundus), and pylorus). Results Of the 93 marker implantation attempts, 59 were successful, i.e., marker in stomach wall and present during entire 5-week radiotherapy course (2-6 successfully placed markers per patient), with no significant difference (Fisher's exact test; P >0.05) in success rate between gold (39/66=59%) and liquid (20/27=74%). Average procedure duration was 24.4 min (range 16-38). No procedure-related complications were reported. All successfully placed markers were visible on all CTs, with 81% visible on ≥95% of CBCTs. Five markers were poorly visible (on <75% of CBCTs), possibly due to small marker volume and peristaltic motion since all five were liquid markers located in the corpus. No migration was observed. Conclusions Endoscopic placement of fiducial markers in the stomach is technically feasible and safe. Being well visible and positionally stable, markers provide a potential benefit for IGRT.
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Affiliation(s)
- Margot Bleeker
- Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Cancer treatment and quality of life, Imaging and biomarkers, Cancer Center Amsterdam, Amsterdam, Netherlands
| | - Astrid van der Horst
- Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Arjan Bel
- Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
- Cancer treatment and quality of life, Imaging and biomarkers, Cancer Center Amsterdam, Amsterdam, Netherlands
| | - Jan-Jakob Sonke
- Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Jeanin E. van Hooft
- Gastroenterology and Hepatology, Leiden University Medical Center, Leiden, Netherlands
- Gastroenterology and Hepatology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
| | - R. E. Pouw
- Cancer treatment and quality of life, Imaging and biomarkers, Cancer Center Amsterdam, Amsterdam, Netherlands
- Gastroenterology and Hepatology, Amsterdam UMC, University of Amsterdam, Amsterdam, Netherlands
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Zhou Y, Sakai M, Li Y, Kubota Y, Okamoto M, Shiba S, Okazaki S, Matsui T, Ohno T. Robust Beam Selection Based on Water Equivalent Thickness Analysis in Passive Scattering Carbon-Ion Radiotherapy for Pancreatic Cancer. Cancers (Basel) 2023; 15:cancers15092520. [PMID: 37173985 PMCID: PMC10177227 DOI: 10.3390/cancers15092520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2023] [Revised: 04/13/2023] [Accepted: 04/20/2023] [Indexed: 05/15/2023] Open
Abstract
Carbon-ion radiotherapy (CIRT) is one of the most effective radiotherapeutic modalities. This study aimed to select robust-beam configurations (BC) by water equivalent thickness (WET) analysis in passive CIRT for pancreatic cancer. The study analyzed 110 computed tomography (CT) images and 600 dose distributions of eight patients with pancreatic cancer. The robustness in the beam range was evaluated using both planning and daily CT images, and two robust BCs for the rotating gantry and fixed port were selected. The planned, daily, and accumulated doses were calculated and compared after bone matching (BM) and tumor matching (TM). The dose-volume parameters for the target and organs at risk (OARs) were evaluated. Posterior oblique beams (120-240°) in the supine position and anteroposterior beams (0° and 180°) in the prone position were the most robust to WET changes. The mean CTV V95% reductions with TM were -3.8% and -5.2% with the BC for gantry and the BC for fixed ports, respectively. Despite ensuring robustness, the dose to the OARs increased slightly with WET-based BCs but remained below the dose constraint. The robustness of dose distribution can be improved by BCs that are robust to ΔWET. Robust BC with TM improves the accuracy of passive CIRT for pancreatic cancer.
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Affiliation(s)
- Yuan Zhou
- Graduate School of Medicine, Gunma University, Maebashi 371-8511, Japan
| | - Makoto Sakai
- Gunma University Heavy Ion Medical Center, Maebashi 371-8511, Japan
| | - Yang Li
- Gunma University Heavy Ion Medical Center, Maebashi 371-8511, Japan
- Department of Radiation Oncology, Harbin Medical University Cancer Hospital, Harbin 150040, China
| | - Yoshiki Kubota
- Gunma University Heavy Ion Medical Center, Maebashi 371-8511, Japan
| | - Masahiko Okamoto
- Graduate School of Medicine, Gunma University, Maebashi 371-8511, Japan
- Gunma University Heavy Ion Medical Center, Maebashi 371-8511, Japan
| | - Shintaro Shiba
- Graduate School of Medicine, Gunma University, Maebashi 371-8511, Japan
- Department of Radiation Oncology, Shonan Kamakura General Hospital, Kamakura 247-8533, Japan
| | - Shohei Okazaki
- Graduate School of Medicine, Gunma University, Maebashi 371-8511, Japan
- Gunma University Heavy Ion Medical Center, Maebashi 371-8511, Japan
| | - Toshiaki Matsui
- Graduate School of Medicine, Gunma University, Maebashi 371-8511, Japan
| | - Tatsuya Ohno
- Graduate School of Medicine, Gunma University, Maebashi 371-8511, Japan
- Gunma University Heavy Ion Medical Center, Maebashi 371-8511, Japan
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Han Z, Sudhyadhom A, Hsu SH, Hu YH, Mak RH, Huynh MA, van Dams RR, Tanguturi S, Venkatachalam V, Mancias JD, Mamon HJ, Martin NE, Lam MB, Leeman JE. Comparison of MR-soft tissue based versus biliary stent based alignment for image guidance in pancreatic SBRT. J Appl Clin Med Phys 2023:e13965. [PMID: 36924220 DOI: 10.1002/acm2.13965] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 01/27/2023] [Accepted: 03/03/2023] [Indexed: 03/18/2023] Open
Abstract
PURPOSE The role of biliary stents in image-guided localization for pancreatic cancer has been inconclusive. To date, stent accuracy has been largely evaluated against implanted fiducials on cone beam computed tomography. We aim to use magnetic resonance (MR) soft tissue as a direct reference to examine the geometric and dosimetric impacts of stent-based localization on the newly available MR linear accelerator. METHODS Thirty pancreatic cancer patients (132 fractions) treated on our MR linear accelerator were identified to have a biliary stent. In our standard adaptive workflow, patients were set up to the target using soft tissue for image registration and structures were re-contoured on daily MR images. The original plan was then projected on treatment anatomy and dose predicted, followed by plan re-optimization and treatment delivery. These online predicted plans were soft tissue-based and served as reference plans. Retrospective image registration to the stent was performed offline to simulate stent-based localization and the magnitude of shifts was taken as the geometric accuracy of stent localization. New predicted plans were generated based on stent-alignment for dosimetric comparison. RESULTS Shifts were within 3 mm for 90% of the cases (mean = 1.5 mm); however, larger shifts up to 7.2 mm were observed. Average PTV coverage dropped by 1.1% with a maximum drop of 26.8%. The mean increase in V35Gy was 0.15, 0.05, 0.02, and 0.02 cc for duodenum, stomach, small bowel and large bowel, respectively. Stent alignment was significantly worse for all metrics except for small bowel (p = 0.07). CONCLUSIONS Overall discrepancy between stent- and soft tissue-alignment was modest; however, large discrepancies were observed for select cases. While PTV coverage loss may be compensated for by using a larger margin, the increase in dose to gastrointestinal organs at risk may limit the role of biliary stents in image-guided localization.
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Affiliation(s)
- Zhaohui Han
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Atchar Sudhyadhom
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Shu-Hui Hsu
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Yue-Houng Hu
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Raymond H Mak
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Mai Anh Huynh
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Ritchell R van Dams
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Shyam Tanguturi
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Veena Venkatachalam
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Joseph D Mancias
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Harvey J Mamon
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Neil E Martin
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Miranda B Lam
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
| | - Jonathan E Leeman
- Department of Radiation Oncology, Brigham and Women's Hospital and Dana-Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, USA
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Opbroek TJ, Willems YC, Verhaegen F, de Ridder R, Hoge C, Melenhorst J, Bakers F, Grabsch HI, Buijsen J, van Limbergen EJ, Canters RA, Berbée M. BioXmark® liquid fiducials to enable radiotherapy tumor boosting in rectal cancer, a feasibility trial. Clin Transl Radiat Oncol 2022; 38:90-95. [PMID: 36407490 PMCID: PMC9668658 DOI: 10.1016/j.ctro.2022.10.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 10/28/2022] [Accepted: 10/30/2022] [Indexed: 11/06/2022] Open
Abstract
BioXmark® is a novel liquid fiducial marker for image-guided radiotherapy. The marker remained stable during chemoradiotherapy in 96% of rectal cancer cases. The fiducial allows for image tracking on CT-based imaging modalities. Marker visibility was good using CT-based imaging without any relevant artifacts. The marker is easy to inject without marker related adverse events.
Background and purpose Dose-escalation in rectal cancer (RCa) may result in an increased complete response rate and thereby enable omission of surgery and organ preservation. In order to implement dose-escalation, it is crucial to develop a technique that allows for accurate image-guided radiotherapy. The aim of the current study was to determine the performance of a novel liquid fiducial marker (BioXmark®) in RCa patients during the radiotherapy course by assessing its positional stability on daily cone-beam CT (CBCT), technical feasibility, visibility on different imaging modalities and safety. Materials and methods Prospective, non-randomized, single-arm feasibility trial with inclusion of twenty patients referred for neoadjuvant chemoradiotherapy for locally advanced RCa. Primary study endpoint was positional stability on CBCT. Furthermore, technical aspects, safety and clinical performance of the marker, such as visibility on different imaging modalities, were evaluated. Results Seventy-four markers from twenty patients were available for analysis. The marker was stable in 96% of the cases. One marker showed clinically relevant migration, one marker was lost before start of treatment and one marker was lost during treatment. Marker visibility was good on computed tomography (CT) and CBCT, and moderate on electronic portal imaging (EPI). Marker visibility on magnetic resonance imaging (MRI) was poor during response evaluation. Conclusion The novel liquid fiducial marker demonstrated positional stability. We provide evidence of the feasibility of the novel fiducial marker for image-guided radiotherapy on daily cone beam CT for RCa patients.
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Zhao W, Shen L, Islam MT, Qin W, Zhang Z, Liang X, Zhang G, Xu S, Li X. Artificial intelligence in image-guided radiotherapy: a review of treatment target localization. Quant Imaging Med Surg 2021; 11:4881-4894. [PMID: 34888196 PMCID: PMC8611462 DOI: 10.21037/qims-21-199] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Accepted: 07/05/2021] [Indexed: 01/06/2023]
Abstract
Modern conformal beam delivery techniques require image-guidance to ensure the prescribed dose to be delivered as planned. Recent advances in artificial intelligence (AI) have greatly augmented our ability to accurately localize the treatment target while sparing the normal tissues. In this paper, we review the applications of AI-based algorithms in image-guided radiotherapy (IGRT), and discuss the indications of these applications to the future of clinical practice of radiotherapy. The benefits, limitations and some important trends in research and development of the AI-based IGRT techniques are also discussed. AI-based IGRT techniques have the potential to monitor tumor motion, reduce treatment uncertainty and improve treatment precision. Particularly, these techniques also allow more healthy tissue to be spared while keeping tumor coverage the same or even better.
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Affiliation(s)
- Wei Zhao
- School of Physics, Beihang University, Beijing, China
| | - Liyue Shen
- Department of Radiation Oncology, Stanford University, Stanford, USA
| | - Md Tauhidul Islam
- Department of Radiation Oncology, Stanford University, Stanford, USA
| | - Wenjian Qin
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Zhicheng Zhang
- Department of Radiation Oncology, Stanford University, Stanford, USA
| | - Xiaokun Liang
- Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Gaolong Zhang
- School of Physics, Beihang University, Beijing, China
| | - Shouping Xu
- Department of Radiation Oncology, PLA General Hospital, Beijing, China
| | - Xiaomeng Li
- Department of Electronic and Computer Engineering, Hong Kong University of Science and Technology, Hong Kong, China
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Yasue K, Fuse H, Asano Y, Kato M, Shinoda K, Ikoma H, Fujisaki T, Tamaki Y. Investigation of fiducial marker recognition possibility by water equivalent length in real-time tracking radiotherapy. Jpn J Radiol 2021; 40:318-325. [PMID: 34655387 DOI: 10.1007/s11604-021-01207-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Accepted: 09/30/2021] [Indexed: 12/28/2022]
Abstract
Real-time tumor tracking radiotherapy (RTRT) systems typically use fiducial markers implanted near the tumor to track the target using X-ray fluoroscopy. Template pattern matching, used in tracking, is often used to automatically localize the fiducial markers. In radiotherapy of the liver, the thickness of the body that can recognize the fiducial markers must be clinically assessed. The purpose of this study was to quantify the recognition of fiducial markers according to body thickness in stereotactic body radiotherapy of the liver using clinical images obtained using SyncTraX FX4. The recognition scores of fiducial markers were examined in relation to water equivalent length (WEL), tube current, and each flat panel detector. The relationship between the contrast ratio of the fiducial marker and the background and the WEL was also investigated. The average recognition score was found to be less than 20 when the WEL was greater than 25 cm. The probability of successful tracking of image recognition was mostly smaller than 0.8 when the WEL was over 30 cm. The relationship between WEL and tube current did not significantly differ between 100 and 140 mA, but there was a significant difference (p < 0.05) for all other combinations. To ensure tracking of fiducial markers during SBRT, if the WEL representing body thickness is longer than 25 cm, the X-ray fluoroscopy arrangement should be determined based on the WEL.
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Affiliation(s)
- Kenji Yasue
- Graduate School of Health Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami, Inashiki, Ibaraki, 300-0394, Japan.,Department of Radiation Technology, Ibaraki Prefectural Central Hospital, 6528, Koibuchi, Kasama, Ibaraki, 309-1793, Japan
| | - Hiraku Fuse
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami, Inashiki, Ibaraki, 300-0394, Japan.
| | - Yuto Asano
- Department of Radiation Technology, Ibaraki Prefectural Central Hospital, 6528, Koibuchi, Kasama, Ibaraki, 309-1793, Japan
| | - Miho Kato
- Department of Radiation Technology, Ibaraki Prefectural Central Hospital, 6528, Koibuchi, Kasama, Ibaraki, 309-1793, Japan
| | - Kazuya Shinoda
- Department of Radiation Technology, Ibaraki Prefectural Central Hospital, 6528, Koibuchi, Kasama, Ibaraki, 309-1793, Japan
| | - Hideaki Ikoma
- Department of Radiation Technology, Ibaraki Prefectural Central Hospital, 6528, Koibuchi, Kasama, Ibaraki, 309-1793, Japan
| | - Tatsuya Fujisaki
- Department of Radiological Sciences, Ibaraki Prefectural University of Health Sciences, 4669-2, Ami, Inashiki, Ibaraki, 300-0394, Japan
| | - Yoshio Tamaki
- Department of Radiation Oncology, Ibaraki Prefectural Central Hospital, 6528, Koibuchi, Kasama, Ibaraki, 309-1793, Japan
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Li Y, Kubota Y, Okamoto M, Shiba S, Okazaki S, Matsui T, Tashiro M, Nakano T, Ohno T. Adaptive planning based on single beam optimization in passive scattering carbon ion radiotherapy for patients with pancreatic cancer. Radiat Oncol 2021; 16:111. [PMID: 34147099 PMCID: PMC8214783 DOI: 10.1186/s13014-021-01841-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Accepted: 06/11/2021] [Indexed: 02/07/2023] Open
Abstract
Background Daily anatomical deviations may distort the dose distribution in carbon ion radiotherapy (CIRT), which may cause treatment failure. Therefore, this study aimed to perform re-planning to maintain the dose coverage in patients with pancreatic cancer with passive scattering CIRT. Methods Eight patients with pancreatic cancer and 95 daily computed tomography (CT) sets were examined. Two types of adaptive plans based on new range compensators (RCs) (AP-1) and initial RCs (AP-2) were generated. In AP-2, each beam was optimized by manually adjusting the range shifter thickness and spread-out Bragg peak size to make dose reduction by < 3% of the original plan. Doses of the original plan with bone matching (BM) and tumor matching (TM) were examined for comparison. We calculated the accumulated dose using the contour and intensity-based deformable image registration algorithm. The dosimetric differences in respect to the original plan were compared between methods. Results Using TM and BM, mean ± standard deviations of daily CTV V95 (%) difference from the original plan was − 5.1 ± 6.2 and − 8.8 ± 8.8, respectively, but 1.2 ± 3.4 in AP-1 and − 0.5 ± 2.1 in AP-2 (P < 0.001). AP-1 and AP-2 enabled to maintain a satisfactory accumulated dose in all patients. The dose difference was 1.2 ± 2.8, − 2,1 ± 1.7, − 7.1 ± 5.2, and − 16.5 ± 15.0 for AP-1, AP-2, TM, and BM, respectively. However, AP-2 caused a dose increase in the duodenum, especially in the left–right beam. Conclusions The possible dose deterioration should be considered when performing the BM, even TM. Re-planning based on single beam optimization in passive scattering CIRT seems an effective and safe method of ensuring the treatment robustness in pancreatic cancer. Further study is necessary to spare healthy tissues, especially the duodenum.
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Affiliation(s)
- Yang Li
- Graduate School of Medicine, Gunma University, Maebashi, Japan.,Department of Radiation Oncology, Harbin Medical University Cancer Hospital, Harbin, China
| | - Yoshiki Kubota
- Gunma University Heavy Ion Medical Center, Maebashi, Japan.
| | | | - Shintaro Shiba
- Gunma University Heavy Ion Medical Center, Maebashi, Japan
| | - Shohei Okazaki
- Gunma University Heavy Ion Medical Center, Maebashi, Japan
| | - Toshiaki Matsui
- Graduate School of Medicine, Gunma University, Maebashi, Japan
| | | | - Takashi Nakano
- Gunma University Heavy Ion Medical Center, Maebashi, Japan
| | - Tatsuya Ohno
- Gunma University Heavy Ion Medical Center, Maebashi, Japan
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10
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van der Horst A, Kok HP, Crezee J. Effect of gastrointestinal gas on the temperature distribution in pancreatic cancer hyperthermia treatment planning. Int J Hyperthermia 2021; 38:229-240. [PMID: 33602033 DOI: 10.1080/02656736.2021.1882709] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
PURPOSE In pancreatic cancer treatment, hyperthermia can be added to increase efficacy of chemo- and/or radiotherapy. Gas in stomach, intestines and colon is often in close proximity to the target volume. We investigated the impact of variations in gastrointestinal gas (GG) on temperature distributions during simulated hyperthermia treatment (HT). METHODS We used sets of one CT and eight cone-beam CT (CBCT) scans obtained prior to/during fractionated image-guided radiotherapy in four pancreatic cancer patients. In Plan2Heat, we simulated locoregional heating by an ALBA-4D phased array radiofrequency system and calculated temperature distributions for (i) the segmented CT (sCT), (ii) sCT with GG replaced by muscle (sCT0), (iii) sCT0 with eight different GG distributions as visible on CBCT inserted (sCTCBCT). We calculated cumulative temperature-volume histograms for the clinical target volume (CTV) for all ten temperature distributions for each patient and investigated the relationship between GG volume and change in ΔT50 (temperature increase at 50% of CTV volume). We determined location and volume of normal tissue receiving a high thermal dose. RESULTS GG volume on CBCT varied greatly (9-991 cm3). ΔT50 increased for increasing GG volume; maximum ΔT50 difference per patient was 0.4-0.6 °C. The risk for GG-associated treatment-limiting hot spots appeared low. Normal tissue high-temperature regions mostly occurred anteriorly; their volume and maximum temperature showed moderate positive correlations with GG volume, while fat-muscle interfaces were associated with higher risks for hot spots. CONCLUSIONS Considerable changes in volume and position of gastrointestinal gas can occur and are associated with clinically relevant tumor temperature differences.
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Affiliation(s)
- Astrid van der Horst
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - H Petra Kok
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Johannes Crezee
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
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11
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Marques S, Bispo M, Leite S, Moreira T, Caldeira A, Moutinho-Ribeiro P, Nunes N. GRUPUGE Perspective: Endoscopic Ultrasound-Guided Fine-Needle Tattooing and Fiducial Placement in Pancreatic Cancer. GE-PORTUGUESE JOURNAL OF GASTROENTEROLOGY 2020; 28:106-110. [PMID: 33791397 DOI: 10.1159/000509194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2020] [Accepted: 05/19/2020] [Indexed: 11/19/2022]
Abstract
In the last 2 decades, endoscopic ultrasound (EUS) has become an important procedure for the diagnosis and management of several pancreatic diseases, including pancreatic cancer. This article presents two recently developed EUS-guided techniques for the management of pancreatic cancer: fine-needle tattooing and fiducial placement. Preoperative EUS-guided fine-needle tattooing of small pancreatic tumors helps in precise localization of these lesions during surgery, potentially ensuring adequate margins of resection while preserving healthy pancreatic tissue. In pancreatic cancer patients planned for imaging-guided radiation therapy, EUS-guided fiducial placement improves the accuracy of target delineation during stereotactic body radiation therapy (SBRT). Hydrogel, a new injectable liquid with multimodal visibility recently approved as a liquid fiducial, is currently under investigation in pancreatic head cancer as an EUS-injected spacer to potentially reduce SBRT gastrointestinal wall toxicity. In this article, GRUPUGE presents an updated perspective of these two EUS-guided techniques, addressing their current clinical applications and technical aspects and analyzing existing data on their efficacy and safety.
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Affiliation(s)
- Susana Marques
- Department of Gastroenterology and Digestive Endoscopy, Champalimaud Foundation, Lisbon, Portugal
| | - Miguel Bispo
- Department of Gastroenterology and Digestive Endoscopy, Champalimaud Foundation, Lisbon, Portugal
| | - Sílvia Leite
- Department of Gastroenterology, Hospital da Senhora da Oliveira, Guimarães, Portugal
| | - Teresa Moreira
- Department of Gastroenterology, Centro Hospitalar Universitário do Porto - Hospital de Santo António, Porto, Portugal
| | - Ana Caldeira
- Department of Gastroenterology, Hospital Amato Lusitano, Castelo Branco, Portugal
| | - Pedro Moutinho-Ribeiro
- Department of Gastroenterology, Centro Hospitalar e Universitário São João, Porto, Portugal
| | - Nuno Nunes
- Department of Gastroenterology, Hospital do Divino Espírito Santo, Ponta Delgada, Portugal
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12
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Bleeker M, Goudschaal K, Bel A, Sonke JJ, Hulshof MCCM, van der Horst A. Feasibility of cone beam CT-guided library of plans strategy in pre-operative gastric cancer radiotherapy. Radiother Oncol 2020; 149:49-54. [PMID: 32387491 DOI: 10.1016/j.radonc.2020.04.057] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2020] [Revised: 04/29/2020] [Accepted: 04/29/2020] [Indexed: 02/07/2023]
Abstract
BACKGROUND AND PURPOSE The stomach displays large anatomical changes in size, shape and position, which implies the need for plan adaptation for gastric cancer patients who receive pre-operative radiotherapy. We evaluated the feasibility and necessity of a CBCT-guided library of plans (LoP) strategy in gastric cancer radiotherapy. METHODS Eight gastric cancer patients treated with 24-25 fractions of single-plan radiotherapy with daily CBCT imaging were included. The target was delineated on the pre-treatment CT and first 5 CBCTs to create a patient-specific LoP. Plan selections were performed by 12 observers in a training stage (2-3 CBCTs per patient) and an assessment stage (17 CBCTs per patient). The observers were asked to select the smallest plan that encompassed the target on the CBCT. A total of 136 plan selections were evaluated in the assessment stage. RESULTS Delineations on CBCTs showed that in 90% of the 40 delineated fractions part of the CTV was outside the PTV based on the pre-treatment CT. At least two-thirds of the observers agreed on the selected plan in 65.2% and 70% of the fractions in the training stage and the assessment stage, respectively. For each patient, at least two different plans from the LoP were the most selected plan. CONCLUSION A CBCT-guided patient-specific LoP strategy is feasible for gastric cancer patients, yielding good agreement in plan selections. Unless generous margins are used to avoid frequent geometric misses, it is likely that part of the target will be missed with single-plan radiotherapy.
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Affiliation(s)
- Margot Bleeker
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands.
| | - Karin Goudschaal
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Jan-Jakob Sonke
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands; Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
| | - Maarten C C M Hulshof
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
| | - Astrid van der Horst
- Department of Radiation Oncology, Amsterdam UMC, University of Amsterdam, Amsterdam, The Netherlands
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13
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van den Ende RPJ, Kerkhof EM, Rigter LS, van Leerdam ME, Peters FP, van Triest B, Staring M, Marijnen CAM, van der Heide UA. Feasibility of Gold Fiducial Markers as a Surrogate for Gross Tumor Volume Position in Image-Guided Radiation Therapy of Rectal Cancer. Int J Radiat Oncol Biol Phys 2019; 105:1151-1159. [PMID: 31476419 DOI: 10.1016/j.ijrobp.2019.08.052] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 08/16/2019] [Accepted: 08/26/2019] [Indexed: 11/29/2022]
Abstract
PURPOSE To evaluate the feasibility of fiducial markers as a surrogate for gross tumor volume (GTV) position in image-guided radiation therapy of rectal cancer. METHODS AND MATERIALS We analyzed 35 fiducials in 19 patients with rectal cancer who received short-course radiation therapy or long-course chemoradiation therapy. Magnetic resonance imaging examinations were performed before and after the first week of radiation therapy, and daily pre- and postirradiation cone beam computed tomography scans were acquired in the first week of radiation therapy. Between the 2 magnetic resonance imaging examinations, the fiducial displacement relative to the center of gravity of the GTV (COGGTV) and the COGGTV displacement relative to bony anatomy were determined. Using the cone beam computed tomography scans, inter- and intrafraction fiducial displacement relative to bony anatomy were determined. RESULTS The systematic error of the fiducial displacement relative to the COGGTV was 2.8, 2.4, and 4.2 mm in the left-right, anterior-posterior (AP), and craniocaudal (CC) directions, respectively. Large interfraction systematic errors of up to 8.0 mm and random errors up to 4.7 mm were found for COGGTV and fiducial displacements relative to bony anatomy, mostly in the AP and CC directions. For tumors located in the mid and upper rectum, these errors were up to 9.4 mm (systematic) and 5.6 mm (random) compared with 4.9 mm and 2.9 mm for tumors in the lower rectum. Systematic and random errors of the intrafraction fiducial displacement relative to bony anatomy were ≤2.1 mm in all directions. CONCLUSIONS Large interfraction errors of the COGGTV and the fiducials relative to bony anatomy were found. Therefore, despite the observed fiducial displacement relative to the COGGTV, the use of fiducials as a surrogate for GTV position reduces the required margins in the AP and CC directions for a GTV boost using image-guided radiation therapy of rectal cancer. This reduction in margin may be larger in patients with tumors located in the mid and upper rectum compared with the lower rectum.
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Affiliation(s)
- Roy P J van den Ende
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands.
| | - Ellen M Kerkhof
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Lisanne S Rigter
- Department of Gastroenterology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Monique E van Leerdam
- Department of Gastroenterology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Femke P Peters
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Baukelien van Triest
- Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, Netherlands
| | - Marius Staring
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands; Division of Image Processing, Department of Radiology, Leiden University Medical Center, Leiden, Netherlands
| | - Corrie A M Marijnen
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands
| | - Uulke A van der Heide
- Department of Radiation Oncology, Leiden University Medical Center, Leiden, Netherlands; Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, Netherlands
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14
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Quantitative evaluation of image recognition performance of fiducial markers in real-time tumor-tracking radiation therapy. Phys Med 2019; 65:33-39. [DOI: 10.1016/j.ejmp.2019.08.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Revised: 08/01/2019] [Accepted: 08/02/2019] [Indexed: 11/15/2022] Open
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15
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16
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Zhao W, Shen L, Han B, Yang Y, Cheng K, Toesca DAS, Koong AC, Chang DT, Xing L. Markerless Pancreatic Tumor Target Localization Enabled By Deep Learning. Int J Radiat Oncol Biol Phys 2019; 105:432-439. [PMID: 31201892 DOI: 10.1016/j.ijrobp.2019.05.071] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2018] [Revised: 05/17/2019] [Accepted: 05/25/2019] [Indexed: 02/07/2023]
Abstract
PURPOSE Deep learning is an emerging technique that allows us to capture imaging information beyond the visually recognizable level of a human being. Because of the anatomic characteristics and location, on-board target verification for radiation delivery to pancreatic tumors is a challenging task. Our goal was to use a deep neural network to localize the pancreatic tumor target on kV x-ray images acquired using an on-board imager for image guided radiation therapy. METHODS AND MATERIALS The network is set up in such a way that the input is either a digitally reconstructed radiograph image or a monoscopic x-ray projection image acquired by the on-board imager from a given direction, and the output is the location of the planning target volume in the projection image. To produce a sufficient number of training x-ray images reflecting the vast number of possible clinical scenarios of anatomy distribution, a series of changes were introduced to the planning computed tomography images, including deformation, rotation, and translation, to simulate inter- and intrafractional variations. After model training, the accuracy of the model was evaluated by retrospectively studying patients who underwent pancreatic cancer radiation therapy. Statistical analysis using mean absolute differences (MADs) and Lin's concordance correlation coefficient were used to assess the accuracy of the predicted target positions. RESULTS MADs between the model-predicted and the actual positions were found to be less than 2.60 mm in anteroposterior, lateral, and oblique directions for both axes in the detector plane. For comparison studies with and without fiducials, MADs are less than 2.49 mm. For all cases, Lin's concordance correlation coefficients between the predicted and actual positions were found to be better than 93%, demonstrating the success of the proposed deep learning for image guided radiation therapy. CONCLUSIONS We demonstrated that markerless pancreatic tumor target localization is achievable with high accuracy by using a deep learning technique approach.
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Affiliation(s)
- Wei Zhao
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Liyue Shen
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Bin Han
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Yong Yang
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Kai Cheng
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Diego A S Toesca
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Albert C Koong
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Daniel T Chang
- Department of Radiation Oncology, Stanford University, Stanford, California
| | - Lei Xing
- Department of Radiation Oncology, Stanford University, Stanford, California.
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17
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Schneider S, Aust DE, Brückner S, Welsch T, Hampe J, Troost EGC, Hoffmann AL. Detectability and structural stability of a liquid fiducial marker in fresh ex vivo pancreas tumour resection specimens on CT and 3T MRI. Strahlenther Onkol 2019; 195:756-763. [PMID: 31143995 DOI: 10.1007/s00066-019-01474-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2019] [Accepted: 05/03/2019] [Indexed: 12/16/2022]
Abstract
PURPOSE To test the detectability of a liquid fiducial marker injected into ex vivo pancreas tumour tissue on magnetic resonance imaging (MRI) and computed tomography (CT). Furthermore, its injection performance using different needle sizes and its structural stability after fixation in formaldehyde were investigated. METHODS Liquid fiducial markers with a volume of 20-100 µl were injected into freshly resected pancreas specimens of three patients with suspected adenocarcinoma. X‑ray guided injection was performed using different needle sizes (18 G, 22 G, 25 G). The specimens were scanned on MRI and CT with clinical protocols. The markers were segmented on CT by signal thresholding. Marker detectability in MRI was assessed in the registered segmentations. Marker volume on CT was compared to the injected volume as a measure of backflow. RESULTS Markers with a volume ≥20 µl were detected as hyperintensity on X‑ray and CT. On T1- and T2-weighted 3T MRI, marker sizes ranging from 20-100 µl were visible as hypointensity. Since most markers were non-spherical, MRI detectability was poor and their differentiation from hypointensities caused by air cavities or surgical clips was only feasible with a reference CT. Marker backflow was only observed when using an 18-G needle. A volume decrease of 6.6 ± 13.0% was observed after 24 h in formaldehyde and, with the exception of one instance, no wash-out occurred. CONCLUSIONS The liquid fiducial marker injected in ex vivo pancreatic resection specimen was visible as hyperintensity on kV X‑ray and CT and as hypointensity on MRI. The marker's size was stable in formaldehyde. A marker volume of ≥50 µL is recommended in clinically used MRI sequences. In vivo injection is expected to improve the markers sphericity due to persisting metabolism and thereby enhance detectability on MRI.
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Affiliation(s)
- Sergej Schneider
- Institute of Radiooncology-OncoRay, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany. .,OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Fetscherstraße 74, PF 41, 01307, Dresden, Germany.
| | - Daniela E Aust
- Institute of Pathology, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Stefan Brückner
- Medical Department 1, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Thilo Welsch
- Department of Visceral, Thoracic and Vascular Surgery, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Jochen Hampe
- Medical Department 1, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Esther G C Troost
- Institute of Radiooncology-OncoRay, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Fetscherstraße 74, PF 41, 01307, Dresden, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Cancer Consortium (DKTK), partner site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), partner site Dresden, Germany: German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden; and Helmholtz Association/Helmholtz-Zentrum Dresden - Rossendorf (HZDR), Dresden, Germany
| | - Aswin L Hoffmann
- Institute of Radiooncology-OncoRay, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Fetscherstraße 74, PF 41, 01307, Dresden, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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18
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Dolde K, Schneider S, Stefanowicz S, Alimusaj M, Flügel B, Saito N, Troost EGC, Pfaffenberger A, Hoffmann AL. Comparison of pancreatic respiratory motion management with three abdominal corsets for particle radiation therapy: Case study. J Appl Clin Med Phys 2019; 20:111-119. [PMID: 31120639 PMCID: PMC6560237 DOI: 10.1002/acm2.12613] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 04/23/2019] [Accepted: 04/25/2019] [Indexed: 01/10/2023] Open
Abstract
Background and purpose Abdominal organ motion seriously compromises the targeting accuracy for particle therapy in patients with pancreatic adenocarcinoma. This study compares three different abdominal corsets regarding their ability to reduce pancreatic motion and their potential usability in particle therapy. Materials and methods A patient‐individualized polyurethane (PU), a semi‐individualized polyethylene (PE), and a patient‐individualized three‐dimensional‐scan based polyethylene (3D‐PE) corset were manufactured for one healthy volunteer. Time‐resolved volumetric four‐dimensional‐magnetic resonance imaging (4D‐MRI) and single‐slice two‐dimensional (2D) cine‐MRI scans were acquired on two consecutive days to compare free‐breathing motion patterns with and without corsets. The corset material properties, such as thickness variance, material homogeneity in Hounsfield units (HU) on computed tomography (CT) scans, and manufacturing features were compared. The water equivalent ratio (WER) of corset material samples was measured using a multi‐layer ionization chamber for proton energies of 150 and 200 MeV. Results All corsets reduced the pancreatic motion on average by 9.6 mm in inferior–superior and by 3.2 mm in anterior‐posterior direction. With corset, the breathing frequency was approximately doubled and the day‐to‐day motion variations were reduced. The WER measurements showed an average value of 0.993 and 0.956 for the PE and 3DPE corset, respectively, and of 0.298 for the PU corset. The PE and 3DPE corsets showed a constant thickness of 2.8 ± 0.2 and 3.8 ± 0.2 mm, respectively and a homogeneous material composition with a standard deviation (SD) of 31 and 32 HU, respectively. The PU corset showed a variable thickness of 4.2 − 25.6 mm and a heterogeneous structure with air inclusions with an SD of 113 HU. Conclusion Abdominal corsets may be effective devices to reduce pancreatic motion. For particle therapy, PE‐based corsets are preferred over PU‐based corset due to their material homogeneity and constant thickness.
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Affiliation(s)
- Kai Dolde
- Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Radiation Research in Oncology, Heidelberg Institute for Radiooncology, Heidelberg, Germany.,Department of Physics and Astronomy, University of Heidelberg, Heidelberg, Germany
| | - Sergej Schneider
- Institute of Radiooncology - OncoRay, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,Faculty of Medicine and University Hospital Carl Gustav Carus, OncoRay - National Center for Radiation Research in Oncology, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Sarah Stefanowicz
- Institute of Radiooncology - OncoRay, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,Faculty of Medicine and University Hospital Carl Gustav Carus, OncoRay - National Center for Radiation Research in Oncology, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
| | - Merkur Alimusaj
- Center for Orthopedic and Trauma Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Beate Flügel
- Center for Orthopedic and Trauma Surgery, Heidelberg University Hospital, Heidelberg, Germany
| | - Nami Saito
- Department of Radiation Oncology, University Clinic Heidelberg, Heidelberg, Germany
| | - Esther G C Troost
- Institute of Radiooncology - OncoRay, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,Faculty of Medicine and University Hospital Carl Gustav Carus, OncoRay - National Center for Radiation Research in Oncology, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), Partner Site Dresden, Germany, German Cancer Research Center (DKFZ), Heidelberg, Germany; Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, and Helmholtz Association / Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden Germany
| | - Asja Pfaffenberger
- Medical Physics in Radiation Oncology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Radiation Research in Oncology, Heidelberg Institute for Radiooncology, Heidelberg, Germany
| | - Aswin L Hoffmann
- Institute of Radiooncology - OncoRay, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,Faculty of Medicine and University Hospital Carl Gustav Carus, OncoRay - National Center for Radiation Research in Oncology, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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Lin T, Ma CMC. Positioning errors of metal localization devices with motion artifacts on kV and MV cone beam CT. BJR Open 2019; 1:20190013. [PMID: 33178943 PMCID: PMC7592481 DOI: 10.1259/bjro.20190013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2019] [Revised: 02/20/2019] [Accepted: 02/21/2019] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVE To investigate motion artifacts on kV CBCT and MV CBCT images with metal localization devices for image-guided radiation therapy. METHODS The 8 μ pelvis CBCT template for the Siemens Artiste MVision and Pelvis template for the Varian IX on-board Exact Arms kV were used to acquire CBCT images in this study. Images from both CBCT modalities were compared in CNRs, metal landmark absolute positions, and image volume distortion on three different planes of view. The images were taken on a breathing-simulated thoracic phantom in which several typical metal localization devices were implanted, including clips and wires for breast patients, gold seeds for prostate patients, and BBs as skin markers. To magnify the artifacts, a 4 cm diameter metal ball was also implanted into the thoracic phantom to mimic the metal artifacts. RESULTS For MV CBCT, the CNR at a 4 sec breathing cycle with 1 cm breathing amplitude was 5.0, 3.4 and 4.6 for clips, gold seeds and BBs, respectively while it was 1.5, 2.0 and 1.6 for the kV CBCT. On the images, the kV CBCT showed symmetric streaking artifacts both in the transverse and longitudinal directions relative to the motion direction. The kV CBCT images predicted 89 % of the expected volume, while the MV CBCT images predicted 95 % of the expected volume. The simulated soft tissue observed in the MVCT could not be detected in the kV CBCT. CONCLUSION The MV CBCT images showed better volume prediction, less streaking effects and better CNRs of a moving metal target, i.e. clips, BBs, gold seeds and metal balls than on the kV CBCT images. The MV CBCT was more advantageous compared to the kV CBCT with less motion artifacts for metal localization devices. ADVANCES IN KNOWLEDGE This study would benefit clinicians to prescribe MV CBCT as localization modality for radiation treatment with moving target when metal markers are implanted.
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Affiliation(s)
- Teh Lin
- Department of Radiation Oncology Fox Chase Cancer Center, Temple University, Philadelphia, USA
| | - Chang-Ming Charlie Ma
- Department of Radiation Oncology Fox Chase Cancer Center, Temple University, Philadelphia, USA
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Dolde K, Dávid C, Echner G, Floca R, Hentschke C, Maier F, Niebuhr N, Ohmstedt K, Saito N, Alimusaj M, Fluegel B, Naumann P, Dreher C, Freitag M, Pfaffenberger A. 4DMRI-based analysis of inter— and intrafractional pancreas motion and deformation with different immobilization devices. Biomed Phys Eng Express 2019. [DOI: 10.1088/2057-1976/aaf9ae] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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21
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van den Ende RPJ, Rigter LS, Kerkhof EM, van Persijn van Meerten EL, Rijkmans EC, Lambregts DMJ, van Triest B, van Leerdam ME, Staring M, Marijnen CAM, van der Heide UA. MRI visibility of gold fiducial markers for image-guided radiotherapy of rectal cancer. Radiother Oncol 2018; 132:93-99. [PMID: 30825976 DOI: 10.1016/j.radonc.2018.11.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Revised: 10/29/2018] [Accepted: 11/25/2018] [Indexed: 01/15/2023]
Abstract
BACKGROUND AND PURPOSE A GTV boost is suggested to result in higher complete response rates in rectal cancer patients, which is attractive for organ preservation. Fiducials may offer GTV position verification on (CB)CT, if the fiducial-GTV spatial relationship can be accurately defined on MRI. The study aim was to evaluate the MRI visibility of fiducials inserted in the rectum. MATERIALS AND METHODS We tested four fiducial types (two Visicoil types, Cook and Gold Anchor), inserted in five patients each. Four observers identified fiducial locations on two MRI exams per patient in two scenarios: without (scenario A) and with (scenario B) (CB)CT available. A fiducial was defined to be consistently identified if 3 out of 4 observers labeled that fiducial at the same position on MRI. Fiducial visibility was scored on an axial and sagittal T2-TSE sequence and a T1 3D GRE sequence. RESULTS Fiducial identification was poor in scenario A for all fiducial types. The Visicoil 0.75 and Gold Anchor were the most consistently identified fiducials in scenario B with 7 out of 9 and 8 out of 11 consistently identified fiducials in the first MRI exam and 2 out of 7 and 5 out of 10 in the second MRI exam, respectively. The consistently identified Visicoil 0.75 and Gold Anchor fiducials were best visible on the T1 3D GRE sequence. CONCLUSION The Visicoil 0.75 and Gold Anchor fiducials were the most visible fiducials on MRI as they were most consistently identified. The use of a registered (CB)CT and a T1 3D GRE MRI sequence is recommended.
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Affiliation(s)
- Roy P J van den Ende
- Department of Radiation Oncology, Leiden University Medical Center, the Netherlands.
| | - Lisanne S Rigter
- Department of Gastroenterology, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Ellen M Kerkhof
- Department of Radiation Oncology, Leiden University Medical Center, the Netherlands
| | | | - Eva C Rijkmans
- Department of Radiation Oncology, Leiden University Medical Center, the Netherlands
| | - Doenja M J Lambregts
- Department of Radiology, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Baukelien van Triest
- Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Monique E van Leerdam
- Department of Gastroenterology, The Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Marius Staring
- Department of Radiation Oncology, Leiden University Medical Center, the Netherlands; Division of Image Processing, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
| | - Corrie A M Marijnen
- Department of Radiation Oncology, Leiden University Medical Center, the Netherlands
| | - Uulke A van der Heide
- Department of Radiation Oncology, Leiden University Medical Center, the Netherlands; Department of Radiation Oncology, The Netherlands Cancer Institute, Amsterdam, the Netherlands
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Nakamura A, Hiraoka M, Itasaka S, Nakamura M, Akimoto M, Ishihara Y, Mukumoto N, Goto Y, Kishi T, Yoshimura M, Matsuo Y, Yano S, Mizowaki T. Evaluation of Dynamic Tumor-tracking Intensity-modulated Radiotherapy for Locally Advanced Pancreatic Cancer. Sci Rep 2018; 8:17096. [PMID: 30459454 PMCID: PMC6244273 DOI: 10.1038/s41598-018-35402-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 11/05/2018] [Indexed: 12/25/2022] Open
Abstract
Intensity-modulated radiotherapy (IMRT) is now regarded as an important treatment option for patients with locally advanced pancreatic cancer (LAPC). To reduce the underlying tumor motions and dosimetric errors during IMRT as well as the burden of respiratory management for patients, we started to apply a new treatment platform of the dynamic tumor dynamic tumor-tracking intensity-modulated radiotherapy (DTT-IMRT) using the gimbaled linac, which can swing IMRT toward the real-time tumor position under patients' voluntary breathing. Between June 2013 and March 2015, ten patients were treated, and the tumor-tracking accuracy and the practical benefits were evaluated. The mean PTV size in DTT-IMRT was 18% smaller than a conventional ITV-based PTV. The root-mean-squared errors between the predicted and the detected tumor positions were 1.3, 1.2, and 1.5 mm in left-right, anterior-posterior, and cranio-caudal directions, respectively. The mean in-room time was 24.5 min. This high-accuracy of tumor-tracking with reasonable treatment time are promising and beneficial to patients with LAPC.
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Affiliation(s)
- Akira Nakamura
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Masahiro Hiraoka
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
| | - Satoshi Itasaka
- Department of Radiation Oncology, Kurashiki Central Hospital, Kurashiki, Japan
| | - Mitsuhiro Nakamura
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Mami Akimoto
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yoshitomo Ishihara
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Nobutaka Mukumoto
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yoko Goto
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takahiro Kishi
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Michio Yoshimura
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yukinori Matsuo
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Shinsuke Yano
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takashi Mizowaki
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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Guerreiro F, Seravalli E, Janssens GO, van de Ven CP, van den Heuvel-Eibrink MM, Raaymakers BW. Intra- and inter-fraction uncertainties during IGRT for Wilms' tumor. Acta Oncol 2018; 57:941-949. [PMID: 29457751 DOI: 10.1080/0284186x.2018.1438655] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
BACKGROUND AND PURPOSE To assess intra- and inter-fraction motion uncertainties, due to displacements of the tumor bed (TB) and organs at risk (OAR), as well as intra- and inter-fraction patient set-up uncertainties, due to positioning variations, during image-guided radiation therapy (IGRT) in children with Wilms' tumor. MATERIAL AND METHODS Four-dimensional computed tomography (4D-CT) and daily pre- and post-treatment cone-beam CT (CBCT)-scans of 15 patients (average 4, range 1-8 years) undergoing flank irradiation after nephrectomy were analyzed. TB (marked by four surgical clips) and OAR motion uncertainties were quantified by displacements of the center of mass in all orthogonal directions. Translational and rotational bone off-sets were recorded for patient set-up uncertainties assessment in all orthogonal directions. The average results, systematic and random errors were computed. RESULTS Average intra- and inter-fraction motion uncertainties were ≤1.1 mm (range: [-6.9;7.9] mm) for the TB and ≤3.2 mm (range: [-9.1;9.6] mm) for the OAR. Average intra- and inter-fraction patient set-up uncertainties were ≤0.1 mm (range: [-3.3;4.8] mm) and ≤0.9° (range: [0.0;2.8°]). Both motion and patient set-up uncertainties were larger for the cranio-caudal direction. Calculated systematic and random errors were ≤2.4 mm for the motion uncertainties and ≤0.8 mm/0.7° for the patient set-up uncertainties. CONCLUSIONS Average motion and patient set-up uncertainties during radiotherapy treatment were found to be limited. However, uncertainties were larger for the cranio-caudal direction and outliers were found in all orthogonal directions. When having available 4D-CT and CBCT information, the use of patient-specific and anisotropic safety margin expansions is advised for both target volume and OAR.
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Affiliation(s)
- Filipa Guerreiro
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Enrica Seravalli
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Geert O. Janssens
- Department of Radiation Oncology, University Medical Center Utrecht, Utrecht, The Netherlands
- Princess Máxima Center for Paediatric Oncology, Utrecht, The Netherlands
| | - Cees P. van de Ven
- Princess Máxima Center for Paediatric Oncology, Utrecht, The Netherlands
| | | | - Bas W. Raaymakers
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
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Gurney-Champion OJ, McQuaid D, Dunlop A, Wong KH, Welsh LC, Riddell AM, Koh DM, Oelfke U, Leach MO, Nutting CM, Bhide SA, Harrington KJ, Panek R, Newbold KL. MRI-based Assessment of 3D Intrafractional Motion of Head and Neck Cancer for Radiation Therapy. Int J Radiat Oncol Biol Phys 2018; 100:306-316. [PMID: 29229323 PMCID: PMC5777665 DOI: 10.1016/j.ijrobp.2017.10.016] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2017] [Revised: 09/14/2017] [Accepted: 10/03/2017] [Indexed: 01/25/2023]
Abstract
PURPOSE To determine the 3-dimensional (3D) intrafractional motion of head and neck squamous cell carcinoma (HNSCC). METHODS AND MATERIALS Dynamic contrast-enhanced magnetic resonance images from 56 patients with HNSCC in the treatment position were analyzed. Dynamic contrast-enhanced magnetic resonance imaging consisted of 3D images acquired every 2.9 seconds for 4 minutes 50 seconds. Intrafractional tumor motion was studied in the 3 minutes 43 seconds of images obtained after initial contrast enhancement. To assess tumor motion, rigid registration (translations only) was performed using a region of interest (ROI) mask around the tumor. The results were compared with bulk body motion from registration to all voxels. Motion was split into systematic motion and random motion. Correlations between the tumor site and random motion were tested. The within-subject coefficient of variation was determined from 8 patients with repeated baseline measures. Random motion was also assessed at the end of the first week (38 patients) and second week (25 patients) of radiation therapy to investigate trends of motion. RESULTS Tumors showed irregular occasional rapid motion (eg, swallowing or coughing), periodic intermediate motion (respiration), and slower systematic drifts throughout treatment. For 95% of the patients, displacements due to systematic and random motion were <1.4 mm and <2.1 mm, respectively, 95% of the time. The motion without an ROI mask was significantly (P<.0001, Wilcoxon signed rank test) less than the motion with an ROI mask, indicating that tumors can move independently from the bony anatomy. Tumor motion was significantly (P=.005, Mann-Whitney U test) larger in the hypopharynx and larynx than in the oropharynx. The within-subject coefficient of variation for random motion was 0.33. The average random tumor motion did not increase notably during the first 2 weeks of treatment. CONCLUSIONS The 3D intrafractional tumor motion of HNSCC is small, with systematic motion <1.4 mm and random motion <2.1 mm 95% of the time.
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Affiliation(s)
- Oliver J Gurney-Champion
- Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK.
| | - Dualta McQuaid
- Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Alex Dunlop
- Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Kee H Wong
- Department of Clinical Oncology, The Royal Marsden NHS Foundation Trust, London, UK
| | - Liam C Welsh
- Department of Clinical Oncology, The Royal Marsden NHS Foundation Trust, London, UK
| | - Angela M Riddell
- Department of Radiology, The Royal Marsden NHS Foundation Trust, London, UK
| | - Dow-Mu Koh
- Department of Radiology, The Royal Marsden NHS Foundation Trust, London, UK
| | - Uwe Oelfke
- Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Martin O Leach
- CR UK Cancer Imaging Centre, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Christopher M Nutting
- Joint Department of Radiotherapy, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Shreerang A Bhide
- Joint Department of Radiotherapy, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Kevin J Harrington
- Joint Department of Physics, The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Rafal Panek
- Department of Medical Physics and Clinical Engineering, Nottingham University Hospitals NHS Trust, Nottingham, UK
| | - Kate L Newbold
- Department of Clinical Oncology, The Royal Marsden NHS Foundation Trust, London, UK
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Koay EJ, Hall W, Park PC, Erickson B, Herman JM. The role of imaging in the clinical practice of radiation oncology for pancreatic cancer. Abdom Radiol (NY) 2018; 43:393-403. [PMID: 29110053 PMCID: PMC5832555 DOI: 10.1007/s00261-017-1373-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Advances in technology have enabled the delivery of high doses of radiation therapy for pancreatic ductal adenocarcinoma (PDAC) with low rates of toxicity. Although the role of radiation for pancreatic cancer continues to evolve, encouraging results with newer techniques indicate that radiation may benefit selected patient populations. Imaging has been central to the modern successes of radiation therapy for PDAC. Here, we review the role of diagnostic imaging, imaging-based planning, and image guidance in radiation oncology practice for PDAC.
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Affiliation(s)
- Eugene J Koay
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, MS 97, Houston, TX, 77030, USA.
| | - William Hall
- Department of Radiation Oncology, Medical College of Wisconsin, Madison, WI, USA
| | - Peter C Park
- Department of Radiation Physics, MD Anderson Cancer Center, Houston, TX, USA
| | - Beth Erickson
- Department of Radiation Oncology, Medical College of Wisconsin, Madison, WI, USA
| | - Joseph M Herman
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, 1515 Holcombe Blvd, MS 97, Houston, TX, 77030, USA
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Evaluation of Bony Anatomy Versus Endobiliary Stents as Surrogates for Volumetric Image Guidance in Pancreatic Cancer. J Med Imaging Radiat Sci 2017; 48:352-359. [PMID: 31047470 DOI: 10.1016/j.jmir.2017.03.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 03/24/2017] [Accepted: 03/27/2017] [Indexed: 12/18/2022]
Abstract
PURPOSE Online treatment setup verification through cone-beam computed tomography (CBCT) in pancreatic cancer patients is limited by low soft tissue contrast. This study aims to quantify the relative positional displacements between bony anatomy and endobiliary stents as surrogates for pancreatic cancers. METHODS Under ethics approval, 258 localization CBCT images from 15 pancreatic patients with endobiliary stents were evaluated. CBCTs were registered through two methods to assess translations and rotations: target adjacent bony anatomy through automatic registration and automatic stent registration through a shaped region of interest. Displacement vector differences between surrogate registrations were calculated and analysed. RESULTS Mean (±standard deviation) translational displacements in the right/left, superior/inferior, anterior/posterior directions were 0.9 ± 3.1 mm, 1.8 ± 4.2 mm, and 0.4 ± 2.5 mm for bone registrations, respectively, and 0.9 ± 5.6 mm, -1.5 ± 5.7 mm, and -0.5 ± 4.3 mm for stent registrations, respectively. Mean (±standard deviation) rotational displacements for pitch, roll, and yaw were 0.16 ± 0.97°, -0.32 ± 0.96°, and -0.77 ± 1.8° for bone registrations, respectively, and -0.94 ± 4.6°, -0.4 ± 7.4°, and -0.13 ± 6.64° for stent registrations, respectively. Mean displacement vector between surrogates was 4 mm, with 43% of fractions measuring displacement vectors >5 mm. A maximum displacement vector of 22.6 mm between surrogates was observed. CONCLUSIONS Varying positional differences were observed between bone and stent registration for pancreas CBCT-image-guided radiation therapy. Setup errors for stent matching were larger than bone registrations. Further research is required to determine if endobiliary stent position is equivalent to the pancreas' location to determine its suitability as a surrogate.
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Jelvehgaran P, Alderliesten T, Weda JJA, de Bruin M, Faber DJ, Hulshof MCCM, van Leeuwen TG, van Herk M, de Boer JF. Visibility of fiducial markers used for image-guided radiation therapy on optical coherence tomography for registration with CT: An esophageal phantom study. Med Phys 2017; 44:6570-6582. [DOI: 10.1002/mp.12624] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2017] [Revised: 09/14/2017] [Accepted: 10/03/2017] [Indexed: 12/13/2022] Open
Affiliation(s)
- Pouya Jelvehgaran
- Department of Biomedical Engineering and Physics; Academic Medical Center; University of Amsterdam; Amsterdam AZ 1105 The Netherlands
- Department of Radiation Oncology; Academic Medical Center; University of Amsterdam; Amsterdam AZ 1105 The Netherlands
- Institute for Laser Life and Biophotonics Amsterdam; Physics and Astronomy; VU University Amsterdam; Amsterdam HV 1081 The Netherlands
| | - Tanja Alderliesten
- Department of Radiation Oncology; Academic Medical Center; University of Amsterdam; Amsterdam AZ 1105 The Netherlands
| | - Jelmer J. A. Weda
- Institute for Laser Life and Biophotonics Amsterdam; Physics and Astronomy; VU University Amsterdam; Amsterdam HV 1081 The Netherlands
| | - Martijn de Bruin
- Department of Biomedical Engineering and Physics; Academic Medical Center; University of Amsterdam; Amsterdam AZ 1105 The Netherlands
- Department of Urology; Academic Medical Center; University of Amsterdam; Amsterdam AZ 1105 The Netherlands
| | - Dirk J. Faber
- Department of Biomedical Engineering and Physics; Academic Medical Center; University of Amsterdam; Amsterdam AZ 1105 The Netherlands
| | - Maarten C. C. M. Hulshof
- Department of Radiation Oncology; Academic Medical Center; University of Amsterdam; Amsterdam AZ 1105 The Netherlands
| | - Ton G. van Leeuwen
- Department of Biomedical Engineering and Physics; Academic Medical Center; University of Amsterdam; Amsterdam AZ 1105 The Netherlands
| | - Marcel van Herk
- Department of Biomedical Engineering and Physics; Academic Medical Center; University of Amsterdam; Amsterdam AZ 1105 The Netherlands
- Institute of Cancer Sciences; University of Manchester; Manchester UK
| | - Johannes F. de Boer
- Institute for Laser Life and Biophotonics Amsterdam; Physics and Astronomy; VU University Amsterdam; Amsterdam HV 1081 The Netherlands
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van der Horst A, Houweling AC, van Tienhoven G, Visser J, Bel A. Dosimetric effects of anatomical changes during fractionated photon radiation therapy in pancreatic cancer patients. J Appl Clin Med Phys 2017; 18:142-151. [PMID: 28980445 PMCID: PMC5689920 DOI: 10.1002/acm2.12199] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 08/22/2017] [Accepted: 08/29/2017] [Indexed: 02/06/2023] Open
Abstract
Pancreatic tumors show large interfractional position variation. In addition, changes in gastrointestinal gas volumes and body contour take place over the course of radiation therapy. We aimed to quantify the effect of these anatomical changes on target dose coverage, for the clinically used fiducial marker‐based patient position verification and, for comparison, also for simulated bony anatomy‐based position verification. Nine consecutive patients were included in this retrospective study. To enable fraction dose calculations on cone‐beam CT (CBCT), the planning CT was deformably registered to each CBCT (13–15 per patient); gas volumes visible on CBCT were copied to the deformed CT. Fraction doses were calculated for the clinically used 10 MV VMAT treatment plan (with for the planning target volume (PTV): D98% = 95%), according to fiducial marker‐based and bony anatomy‐based image registrations. Dose distributions were rigidly summed to yield the accumulated dose. To evaluate target dose coverage, we defined an iCTV+5 mm volume, i.e., the internal clinical target volume (iCTV) expanded with a 5 mm margin to account for remaining uncertainties including delineation uncertainties. We analyzed D98%, Dmean, and D2% for iCTV+5 mm and PTV (i.e., iCTV plus 10 mm margin). We found that for fiducial marker‐based registration, differences between fraction doses and planned dose were minimal. For bony anatomy‐based registration, fraction doses differed considerably, resulting in large differences between planned and accumulated dose for some patients, up to a decrease in D98% of the iCTV+5 mm from 95.9% to 85.8%. Our study shows that fractionated photon irradiation of pancreatic tumors is robust against variations in body contour and gastrointestinal gas, with dose coverage only mildly affected. However, as a result of interfractional tumor position variations, target dose coverage can severely decline when using bony anatomy for patient position verification. Therefore, the use of intratumoral fiducial marker‐based daily position verification is essential in pancreatic cancer patients.
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Affiliation(s)
- Astrid van der Horst
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Antonetta C Houweling
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Geertjan van Tienhoven
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Jorrit Visser
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
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Cheesman AR, DiMaio CJ. Role and technique of endoscopic ultrasound placement of fiducial markers in gastrointestinal malignancies. TECHNIQUES IN GASTROINTESTINAL ENDOSCOPY 2017. [DOI: 10.1016/j.tgie.2017.10.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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van Dijk IWEM, Huijskens SC, de Jong R, Visser J, Fajardo RD, Rasch CRN, Alderliesten T, Bel A. Interfractional renal and diaphragmatic position variation during radiotherapy in children and adults: is there a difference? Acta Oncol 2017; 56:1065-1071. [PMID: 28281356 DOI: 10.1080/0284186x.2017.1299936] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND Pediatric safety margins are generally based on data from adult studies; however, adult-based margins might be too large for children. The aim of this study was to quantify and compare interfractional organ position variation in children and adults. MATERIAL AND METHODS For 35 children and 35 adults treated with thoracic/abdominal irradiation, 850 (range 5-30 per patient) retrospectively collected cone beam CT images were registered to the reference CT that was used for radiation treatment planning purposes. Renal position variation was assessed in three orthogonal directions and summarized as 3D vector lengths. Diaphragmatic position variation was assessed in the cranio-caudal (CC) direction only. We calculated means and SDs to estimate group systematic (Σ) and random errors (σ) of organ position variation. Finally, we investigated possible correlations between organ position variation and patients' height. RESULTS Interfractional organ position variation was different in children and adults. Median 3D right and left kidney vector lengths were significantly smaller in children than in adults (2.8, 2.9 mm vs. 5.6, 5.2 mm, respectively; p < .05). Generally, the pediatric Σ and σ were significantly smaller than in adults (p < .007). Overall and within both subgroups, organ position variation and patients' height were only negligibly correlated. CONCLUSIONS Interfractional renal and diaphragmatic position variation in children is smaller than in adults indicating that pediatric margins should be defined differently from adult margins. Underlying mechanisms and other components of geometrical uncertainties need further investigation to explain differences and to appropriately define pediatric safety margins.
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Affiliation(s)
- Irma W. E. M. van Dijk
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Sophie C. Huijskens
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Rianne de Jong
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Jorrit Visser
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Raquel Dávila Fajardo
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Coen R. N. Rasch
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Tanja Alderliesten
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Gurney-Champion OJ, Versteijne E, van der Horst A, Lens E, Rütten H, Heerkens HD, Paardekooper GMRM, Berbee M, Rasch CRN, Stoker J, Engelbrecht MRW, van Herk M, Nederveen AJ, Klaassen R, van Laarhoven HWM, van Tienhoven G, Bel A. Addition of MRI for CT-based pancreatic tumor delineation: a feasibility study. Acta Oncol 2017; 56:923-930. [PMID: 28375667 DOI: 10.1080/0284186x.2017.1304654] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
PURPOSE To assess the effect of additional magnetic resonance imaging (MRI) alongside the planning computed tomography (CT) scan on target volume delineation in pancreatic cancer patients. MATERIAL AND METHODS Eight observers (radiation oncologists) from six institutions delineated the gross tumor volume (GTV) on 3DCT, and internal GTV (iGTV) on 4DCT of four pancreatic cancer patients, while MRI was available in a second window (CT + MRI). Variations in volume, generalized conformity index (CIgen), and overall observer variation, expressed as standard deviation (SD) of the distances between delineated surfaces, were analyzed. CIgen is a measure of overlap of the delineated iGTVs (1 = full overlap, 0 = no overlap). Results were compared with those from an earlier study that assessed the interobserver variation by the same observers on the same patients on CT without MRI (CT-only). RESULTS The maximum ratios between delineated volumes within a patient were 6.1 and 22.4 for the GTV (3DCT) and iGTV (4DCT), respectively. The average (root-mean-square) overall observer variations were SD = 0.41 cm (GTV) and SD = 0.73 cm (iGTV). The mean CIgen was 0.36 for GTV and 0.37 for iGTV. When compared to the iGTV delineated on CT-only, the mean volumes of the iGTV on CT + MRI were significantly smaller (32%, Wilcoxon signed-rank, p < .0005). The median volumes of the iGTV on CT + MRI were included for 97% and 92% in the median volumes of the iGTV on CT. Furthermore, CT + MRI showed smaller overall observer variations (root-mean-square SD = 0.59 cm) in six out of eight delineated structures compared to CT-only (root-mean-square SD = 0.72 cm). However, large local observer variations remained close to biliary stents and pathological lymph nodes, indicating issues with instructions and instruction compliance. CONCLUSIONS The availability of MRI images during target delineation of pancreatic cancer on 3DCT and 4DCT resulted in smaller target volumes and reduced the interobserver variation in six out of eight delineated structures.
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Affiliation(s)
- Oliver J. Gurney-Champion
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Eva Versteijne
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Astrid van der Horst
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Eelco Lens
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Heidi Rütten
- Department of Radiation Oncology, Radboud University Medical Center, Nijmegen, the Netherlands
| | - Hanne D. Heerkens
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, the Netherlands
| | | | - Maaike Berbee
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - Coen R. N. Rasch
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Jaap Stoker
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Marc R. W. Engelbrecht
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Marcel van Herk
- Faculty of Biology, Medicine & Health, Division of Cancer Sciences, University of Manchester and Christie NHS Trust, Manchester, UK
| | - Aart J. Nederveen
- Department of Radiology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Remy Klaassen
- Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Hanneke W. M. van Laarhoven
- Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Geertjan van Tienhoven
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, the Netherlands
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Versteijne E, Lens E, van der Horst A, Bel A, Visser J, Punt CJA, Suker M, van Eijck CHJ, van Tienhoven G. Quality assurance of the PREOPANC trial (2012-003181-40) for preoperative radiochemotherapy in pancreatic cancer : The dummy run. Strahlenther Onkol 2017; 193:630-638. [PMID: 28608305 PMCID: PMC5519646 DOI: 10.1007/s00066-017-1153-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 05/11/2017] [Indexed: 01/09/2023]
Abstract
Background The Dutch Pancreatic Cancer Group initiated the national, multicentre, controlled PREOPANC trial, randomising between preoperative radiochemotherapy and direct explorative laparotomy for patients with (borderline) resectable pancreatic cancer. The aim of this dummy run is to evaluate compliance with the radiotherapy protocol of this trial, and the quality of delineation and radiation plans. Methods Eleven radiation oncology departments open for accrual of patients in the PREOPANC trial were provided with all necessary information of a selected ‘dummy’ patient. Each institute was asked to delineate the target volumes, including gross tumour volume, internal gross tumour volume (iGTV), internal clinical target volume, and planning target volume. The institutions were also asked to provide a radiation treatment plan in accordance with the PREOPANC trial protocol. Results The range of the iGTV was 19.3–77.2 cm3 with a mean iGTV of 41.5 cm3 (standard deviation 14.8 cm3). Nine institutions made a treatment plan using an arc technique for treatment delivery, one an intensity modulated technique and one a 3-field conformal technique. All institutions reached the prescribed target coverage, without exceeding the organs at risk constraints. The institution with the 3‑field conformal technique was advised to use a more sophisticated technique (e. g. volumetric modulated arc therapy) to reduce the dose to the spinal cord. Conclusion All institutions showed acceptable deviations from the PREOPANC trial protocol and achieved an acceptable quality of delineation and radiation technique. All institutions were allowed to continue participation in the PREOPANC trial. Electronic supplementary material The online version of this article (doi:10.1007/s00066-017-1153-6) contains supplementary material, which is available to authorized users. Supplementary material: PREOPANC Protocol, version 11, radiotherapy part
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Affiliation(s)
- Eva Versteijne
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| | - Eelco Lens
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Astrid van der Horst
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Jorrit Visser
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Cornelis J A Punt
- Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Mustafa Suker
- Department of Surgery, Erasmus Medical Center, Erasmus University, 's-Gravendijkwal 230, 3015 CE, Rotterdam, The Netherlands
| | - Casper H J van Eijck
- Department of Surgery, Erasmus Medical Center, Erasmus University, 's-Gravendijkwal 230, 3015 CE, Rotterdam, The Netherlands
| | - Geertjan van Tienhoven
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
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Akimoto M, Nakamura M, Nakamura A, Mukumoto N, Kishi T, Goto Y, Mizowaki T, Hiraoka M. Inter- and Intrafractional Variation in the 3-Dimensional Positions of Pancreatic Tumors Due to Respiration Under Real-Time Monitoring. Int J Radiat Oncol Biol Phys 2017; 98:1204-1211. [PMID: 28721905 DOI: 10.1016/j.ijrobp.2017.03.042] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2016] [Revised: 03/15/2017] [Accepted: 03/23/2017] [Indexed: 10/19/2022]
Abstract
PURPOSE To quantify the 3-dimensional pancreatic tumor motion during the overall treatment course using real-time orthogonal kilovoltage X-ray imaging. METHODS AND MATERIALS This study included 10 patients with pancreatic cancer who underwent 6-port static intensity modulated radiation therapy with real-time tumor tracking in 15 fractions, except for 1 patient (5 fractions). The tumor and abdominal wall positions were acquired simultaneously during the overall treatment course. Then the tumor motion amplitude and reference positions were determined. RESULTS The mean tumor amplitudes were 4.9, 6.5, and 13.4 mm in the left-right (LR), anterior-posterior (AP), and superior-inferior (SI) directions, respectively. The intrafractional variations of the reference tumor position were up to 5.4, 10.2, and 10.7 mm in the LR, AP, and SI directions, and those of the reference abdominal position were up to 10.5 mm. The reference tumor position drifted significantly in the AP and SI directions after 10 minutes, and that of abdominal wall motion drifted during the first 15 minutes (P<.05). The interfractional variation of the reference tumor position after setup correction, based on bony structures, was up to 8.9, 9.8, and 11.0 mm in the LR, AP, and SI directions, respectively. CONCLUSIONS Appropriate respiratory motion management techniques should be applied for the accurate localization of pancreatic tumors.
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Affiliation(s)
- Mami Akimoto
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Mitsuhiro Nakamura
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
| | - Akira Nakamura
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Nobutaka Mukumoto
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takashi Kishi
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Yoko Goto
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Takashi Mizowaki
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
| | - Masahiro Hiraoka
- Department of Radiation Oncology and Image-Applied Therapy, Graduate School of Medicine, Kyoto University, Kyoto, Japan
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Versteijne E, Gurney-Champion OJ, van der Horst A, Lens E, Kolff MW, Buijsen J, Ebrahimi G, Neelis KJ, Rasch CRN, Stoker J, van Herk M, Bel A, van Tienhoven G. Considerable interobserver variation in delineation of pancreatic cancer on 3DCT and 4DCT: a multi-institutional study. Radiat Oncol 2017; 12:58. [PMID: 28335780 PMCID: PMC5364627 DOI: 10.1186/s13014-017-0777-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2016] [Accepted: 02/06/2017] [Indexed: 12/13/2022] Open
Abstract
Background The delineation of pancreatic tumors on CT is challenging. In this study, we quantified the interobserver variation for pancreatic tumor delineation on 3DCT as well as on 4DCT. Methods Eight observers (radiation oncologists) from six institutions delineated pancreatic tumors of four patients with (borderline) resectable pancreatic cancer. The study consisted of two stages. In the 3DCT-stage, the gross tumor volume (GTV) was delineated on a contrast-enhanced scan. In the 4DCT-stage, the internal GTV (iGTV) was delineated, accounting for the respiratory motion. We calculated the volumes of the (i)GTV, the overlap of the delineated volumes (expressed as generalized conformity index: CIgen), the local observer variation (local standard deviation: SD) and the overall observer variation (overall SD). We compared these results between GTVs and iGTVs. Additionally, observers were asked to fill out a questionnaire concerning the difficulty of the delineation and their experience in delineating pancreatic tumors. Results The ratios of the largest to the smallest delineated GTV and iGTV within the same patient were 6.8 and 16.5, respectively. As the iGTV incorporates the GTV during all respiratory phases, the mean volumes of the iGTV (40.07 cm3) were larger than those of the GTV (29.91 cm3). For all patients, CIgen was larger for the iGTV than for the GTV. The mean overall observer variation (root-mean-square of all local SDs over four patients) was 0.63 cm and 0.80 cm for GTV and iGTV, respectively. The largest local observer variations were seen close to biliary stents and suspicious pathological enlarged lymph nodes, as some observers included them and some did not. This variation was more pronounced for the iGTV than for the GTV. The observers rated the 3DCT-stage and 4DCT-stage equally difficult and treated on average three to four pancreatic cancer patients per year. Conclusions A considerable interobserver variation in delineation of pancreatic tumors was observed. This variation was larger for 4D than for 3D delineation. The largest local observer variation was found around biliary stents and suspicious pathological enlarged lymph nodes. Electronic supplementary material The online version of this article (doi:10.1186/s13014-017-0777-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Eva Versteijne
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.
| | - Oliver J Gurney-Champion
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.,Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Astrid van der Horst
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Eelco Lens
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - M Willemijn Kolff
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Jeroen Buijsen
- Department of Radiation Oncology, MAASTRO clinic, Doctor Tanslaan 12, 6229 ET, Maastricht, The Netherlands
| | - Gati Ebrahimi
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Karen J Neelis
- Department of Radiation Oncology, Leiden University Medical Center, Leiden University, Postbus 9600, 2300 RC, Leiden, The Netherlands
| | - Coen R N Rasch
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Jaap Stoker
- Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Marcel van Herk
- Faculty of Biology, Medicine & Health, Division of Molecular & Clinical Cancer Sciences, University of Manchester and Christie NHS trust, Oxford Road Manchester, M13 9PL, Manchester, United Kingdom
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Geertjan van Tienhoven
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
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Gurney-Champion OJ, Bruins Slot T, Lens E, van der Horst A, Klaassen R, van Laarhoven HWM, van Tienhoven G, van Hooft JE, Nederveen AJ, Bel A. Quantitative assessment of biliary stent artifacts on MR images: Potential implications for target delineation in radiotherapy. Med Phys 2017; 43:5603. [PMID: 27782717 DOI: 10.1118/1.4962476] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
PURPOSE Biliary stents may cause susceptibility artifacts, gradient-induced artifacts, and radio frequency (RF) induced artifacts on magnetic resonance images, which can hinder accurate target volume delineation in radiotherapy. In this study, the authors investigated and quantified the magnitude of these artifacts for stents of different materials. METHODS Eight biliary stents made of nitinol, platinum-cored nitinol, stainless steel, or polyethylene from seven vendors, with different lengths (57-98 mm) and diameters (3.0-11.7 mm), were placed in a phantom. To quantify the susceptibility artifacts sequence-independently, ΔB0-maps and T2∗-maps were acquired at 1.5 and 3 T. To study the effect of the gradient-induced artifacts at 3 T, signal decay in images obtained with maximum readout gradient-induced artifacts was compared to signal decay in reference scans. To quantify the RF induced artifacts at 3 T, B1-maps were acquired. Finally, ΔB0-maps and T2∗-maps were acquired at 3 T of two pancreatic cancer patients who had received platinum-cored nitinol biliary stents. RESULTS Outside the stent, susceptibility artifacts dominated the other artifacts. The stainless steel stent produced the largest susceptibility artifacts. The other stents caused decreased T2∗ up to 5.1 mm (1.5 T) and 8.5 mm (3 T) from the edge of the stent. For sequences with a higher bandwidth per voxel (1.5 T: BWvox > 275 Hz/voxel; 3 T: BWvox > 500 Hz/voxel), the B0-related susceptibility artifacts were negligible (<0.2 voxels). The polyethylene stent showed no artifacts. In vivo, the changes in B0 and T2∗ induced by the stent were larger than typical variations in B0 and T2∗ induced by anatomy when the stent was at an angle of 30° with the main magnetic field. CONCLUSIONS Susceptibility artifacts were dominating over the other artifacts. The magnitudes of the susceptibility artifacts were determined sequence-independently. This method allows to include additional safety margins that ensure target irradiation.
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Affiliation(s)
- Oliver J Gurney-Champion
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands and Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Thijs Bruins Slot
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Eelco Lens
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Astrid van der Horst
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Remy Klaassen
- Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands and Laboratory for Experimental Oncology and Radiobiology, Center for Experimental Molecular Medicine, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Hanneke W M van Laarhoven
- Department of Medical Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Geertjan van Tienhoven
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Jeanin E van Hooft
- Department of Gastroenterology and Hepatology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Aart J Nederveen
- Department of Radiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, Amsterdam 1105 AZ, The Netherlands
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Ohira S, Isono M, Ueda Y, Hirata T, Ashida R, Takahashi H, Miyazaki M, Takashina M, Koizumi M, Teshima T. Assessment with cone-beam computed tomography of intrafractional motion and interfractional position changes of resectable and borderline resectable pancreatic tumours with implanted fiducial marker. Br J Radiol 2017; 90:20160815. [PMID: 28256908 DOI: 10.1259/bjr.20160815] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
OBJECTIVE The volume of targets to which a high radiation dose can be delivered is limited for pancreatic radiotherapy. We assessed changes in movements of pancreatic tumours between simulation and treatment and determined compensatory margins. METHODS For 23 patients, differences in implanted fiducial marker motion magnitude (MMM) and mean marker position (MMP) between four-dimensional CT and cone-beam CT were measured. Subsequently, residual uncertainty was simulated after no action level (NAL) and extended no action level (eNAL) protocols were adopted. RESULTS With no correction, respective 95th percentile of MMM were 4.5 mm, 6.2 mm and 16.0 mm and systematic (random) errors of MMP were 2.8 mm (3.3 mm), 3.2 mm (2.0 mm) and 5.9 mm (4.0 mm) in the left-right (L-R), anteroposterior (A-P) and superoinferior (S-I) directions, so that large margins were required (L-R, 10.5 mm; A-P, 11.7 mm; and S-I, 24.8 mm). NAL reduced systematic errors of MMP, but resultant margins remained large (L-R, 8.0 mm; A-P, 9.6 mm; and S-I, 18.1 mm). eNAL compensated for time trends and obtained minimal margins (L-R, 6.7 mm; A-P, 6.7 mm; and S-I, 15.2 mm). CONCLUSION Motion magnitude and position of pancreatic tumours during simulation are frequently not representative of that during treatment. eNAL compensated for systematic interfractional position change and would be a practical approach for improving targeting accuracy. Advances in knowledge: Considerably large margins, especially in the S-I direction, were required to compensate for intrafractional motion and interfractional position changes of the pancreatic tumour. An application of eNAL was an effective strategy to diminish these margins.
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Affiliation(s)
- Shingo Ohira
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.,2 Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Japan
| | - Masaru Isono
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Yoshihiro Ueda
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan.,3 Department of Radiation Oncology, Osaka University Graduate School of Medicine, Suita, Japan
| | - Takero Hirata
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Reiko Ashida
- 4 Department of Cancer survey and gastrointestinal oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Hidenori Takahashi
- 5 Department of Surgery, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Masayoshi Miyazaki
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
| | - Masaaki Takashina
- 2 Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Japan
| | - Masahiko Koizumi
- 2 Department of Medical Physics and Engineering, Osaka University Graduate School of Medicine, Suita, Japan
| | - Teruki Teshima
- 1 Department of Radiation Oncology, Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka, Japan
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Houweling AC, Crama K, Visser J, Fukata K, Rasch CRN, Ohno T, Bel A, van der Horst A. Comparing the dosimetric impact of interfractional anatomical changes in photon, proton and carbon ion radiotherapy for pancreatic cancer patients. Phys Med Biol 2017; 62:3051-3064. [PMID: 28252445 DOI: 10.1088/1361-6560/aa6419] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Radiotherapy using charged particles is characterized by a low dose to the surrounding healthy organs, while delivering a high dose to the tumor. However, interfractional anatomical changes can greatly affect the robustness of particle therapy. Therefore, we compared the dosimetric impact of interfractional anatomical changes (i.e. body contour differences and gastrointestinal gas volume changes) in photon, proton and carbon ion therapy for pancreatic cancer patients. In this retrospective planning study, photon, proton and carbon ion treatment plans were created for 9 patients. Fraction dose calculations were performed using daily cone-beam CT (CBCT) images. To this end, the planning CT was deformably registered to each CBCT; gastrointestinal gas volumes were delineated on the CBCTs and copied to the deformed CT. Fraction doses were accumulated rigidly. To compare planned and accumulated dose, dose-volume histogram (DVH) parameters of the planned and accumulated dose of the different radiotherapy modalities were determined for the internal gross tumor volume, internal clinical target volume (iCTV) and organs-at-risk (OARs; duodenum, stomach, kidneys, liver and spinal cord). Photon plans were highly robust against interfractional anatomical changes. The difference between the planned and accumulated DVH parameters for the photon plans was less than 0.5% for the target and OARs. In both proton and carbon ion therapy, however, coverage of the iCTV was considerably reduced for the accumulated dose compared with the planned dose. The near-minimum dose ([Formula: see text]) of the iCTV reduced with 8% for proton therapy and with 10% for carbon ion therapy. The DVH parameters of the OARs differed less than 3% for both particle modalities. Fractionated radiotherapy using photons is highly robust against interfractional anatomical changes. In proton and carbon ion therapy, such changes can severely reduce the dose coverage of the target.
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Affiliation(s)
- Antonetta C Houweling
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
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Hwang JH, Aslanian HR, Thosani N, Goodman A, Manfredi M, Navaneethan U, Pannala R, Parsi MA, Smith ZL, Sullivan SA, Banerjee S, Maple JT. Devices for use with EUS. VIDEOGIE : AN OFFICIAL VIDEO JOURNAL OF THE AMERICAN SOCIETY FOR GASTROINTESTINAL ENDOSCOPY 2017; 2:35-45. [PMID: 29905238 PMCID: PMC5990542 DOI: 10.1016/j.vgie.2016.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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Lens E, Kotte ANTJ, Patel A, Heerkens HD, Bal M, van Tienhoven G, Bel A, van der Horst A, Meijer GJ. Probabilistic treatment planning for pancreatic cancer treatment: prospective incorporation of respiratory motion shows only limited dosimetric benefit. Acta Oncol 2017; 56:398-404. [PMID: 27885864 DOI: 10.1080/0284186x.2016.1257863] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
BACKGROUND We introduced a probabilistic treatment planning approach that prospectively incorporates respiratory-induced motion in the treatment plan optimization. The aim of this study was to determine the potential dosimetric benefit by comparing this approach to the use of an internal target volume (ITV). MATERIAL AND METHOD We retrospectively compared the probabilistic respiratory motion-incorporated (RMI) approach to the ITV approach for 18 pancreatic cancer patients, for seven simulated respiratory amplitudes from 5 to 50 mm in the superior-inferior (SI) direction. For each plan, we assessed the target coverage (required: D98%≥95% of 50 Gy prescribed dose). For the RMI plans, we investigated whether target coverage was robust against daily variations in respiratory amplitude. We determined the distance between the clinical target volume and the 30 Gy isodose line (i.e. dose gradient steepness) in the SI direction. To investigate the clinical benefit of the RMI approach, we created for each patient an ITV and RMI treatment plan for the three-dimensional (3D) respiratory amplitudes observed on their pretreatment 4D computed tomography (4DCT). We determined Dmean, V30Gy, V40Gy and V50Gy for the duodenum. RESULTS All treatment plans yielded good target coverage. The RMI plans were robust against respiratory amplitude variations up to 10 mm, as D98% remained ≥95%. We observed steeper dose gradients compared to the ITV approach, with a mean decrease from 25.9 to 19.2 mm for a motion amplitude of 50 mm. For the 4DCT motion amplitudes, the RMI approach resulted in a mean decrease of 0.43 Gy, 1.1 cm3, 1.4 cm3 and 0.9 cm3 for the Dmean, V30Gy, V40Gy and V50Gy of the duodenum, respectively. CONCLUSION The probabilistic treatment planning approach yielded significantly steeper dose gradients and therefore significantly lower dose to surrounding healthy tissues than the ITV approach. However, the observed dosimetric gain for clinically observed respiratory motion amplitudes for this patient group was limited.
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Affiliation(s)
- Eelco Lens
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Alexis N. T. J. Kotte
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Ajay Patel
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
| | - Hanne D. Heerkens
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
| | | | - Geertjan van Tienhoven
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Astrid van der Horst
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Gert J. Meijer
- Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
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Abe S, Kubota Y, Shibuya K, Koyama Y, Abe T, Ohno T, Nakano T. Fiducial marker matching versus vertebral body matching: Dosimetric impact of patient positioning in carbon ion radiotherapy for primary hepatic cancer. Phys Med 2017; 33:114-120. [PMID: 28057427 DOI: 10.1016/j.ejmp.2016.12.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Revised: 12/22/2016] [Accepted: 12/27/2016] [Indexed: 12/25/2022] Open
Abstract
PURPOSE The aim of this study was to compare the dose-volume parameters of fiducial marker matching (MM) with vertebral body matching (VM) in patient positioning for carbon ion radiotherapy for primary hepatic cancer. MATERIALS AND METHODS Twenty patients with primary hepatic cancer were retrospectively studied to assess changes in reproducibility of tumor position and dose distribution on two CT scans. One was for treatment planning and another was for dose confirmation, acquired the day before the first treatment day. The coverage of the clinical target volume (CTV) (D98) and normal liver volume excluding the CTV which received 20Gy relative biological effectiveness (RBE) (V20) were used as evaluation parameters. Additionally, the correlation of tumor movement and D98 was calculated in VM and MM. The prescription dose was 60.0Gy (RBE) delivered in four fractions (15Gy/fx). RESULTS The median (range) D98 for VM and MM was 57.9 (20.8-59.9) and 59.9 (57.2-60.3) Gy (RBE), respectively. The median (range) V20 for VM and MM was 17.9 (4.8-44.4) and 16.2 (4.7-44.9) Gy (RBE), respectively. The D98 for MM was significantly larger than that for VM (p=0.001), although V20 showed no significant difference (p>0.05). Twelve patients were clinically acceptable (D98>57Gy (RBE)) with VM, while all patients were clinically acceptable with MM. Marker movement correlated with a decrease of D98 for VM (R=-0.814). CONCLUSION Compared with VM, MM was clinically acceptable in all patients. This suggests that MM is more robust than VM.
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Affiliation(s)
- Satoshi Abe
- Department of Radiology, Gunma University Hospital, 3-39-15 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Yoshiki Kubota
- Gunma University Heavy Ion Medical Center, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan.
| | - Kei Shibuya
- Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Yoshinori Koyama
- Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Takanori Abe
- Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Tatsuya Ohno
- Gunma University Heavy Ion Medical Center, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
| | - Takashi Nakano
- Gunma University Heavy Ion Medical Center, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan; Department of Radiation Oncology, Gunma University Graduate School of Medicine, 3-39-22 Showa-machi, Maebashi, Gunma 371-8511, Japan
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Abdominal organ motion during inhalation and exhalation breath-holds: pancreatic motion at different lung volumes compared. Radiother Oncol 2016; 121:268-275. [DOI: 10.1016/j.radonc.2016.09.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 09/19/2016] [Accepted: 09/25/2016] [Indexed: 11/24/2022]
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Lens E, van der Horst A, Versteijne E, Bel A, van Tienhoven G. Considerable pancreatic tumor motion during breath-holding. Acta Oncol 2016; 55:1360-1368. [PMID: 27583771 DOI: 10.1080/0284186x.2016.1221532] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Breath-holding (BH) is often used to reduce abdominal organ motion during radiotherapy. However, for inhale BH, abdominal tumor motion during BH has not yet been investigated. The aim of this study was to quantify tumor motion during inhale BH and tumor position variations between consecutive inhale BHs in pancreatic cancer patients. MATERIAL AND METHODS Twelve patients with intratumoral fiducials were included and asked to perform three consecutive 30-second inhale BHs on each of three measurement days. During BH, lateral fluoroscopic movies were obtained and a two-dimensional (2D) image correlation algorithm was used to track the fiducials and the diaphragm, yielding the tumor and diaphragm motion during each BH. The tumor position variation between consecutive BHs was obtained from the difference in initial tumor position between consecutive BHs on a single measurement day. RESULTS We observed tumor motion during BH with a mean absolute maximum displacement over all BHs of 4.2 mm (range 1.0-11.0 mm) in inferior-superior (IS) direction and 2.7 mm (range 0.5-8.0 mm) in anterior-posterior (AP) direction. We found only a moderate correlation between tumor and diaphragm motion in the IS direction (Pearson's correlation coefficient |r|>0.6 in 45 of 76 BHs). The mean tumor position variation between consecutive BHs was 0.2 [standard deviation (SD) 1.7] mm in the inferior direction and 0.5 (SD 0.8) mm in the anterior direction. CONCLUSION We observed substantial pancreatic tumor motion during BH as well as considerable position variation between consecutive BHs on a single day. We recommend further quantifying these uncertainties before introducing breath-hold during radiation treatment of pancreatic cancer patients. Also, the diaphragm cannot be used as a surrogate for pancreatic tumor motion.
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Affiliation(s)
- Eelco Lens
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Astrid van der Horst
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Eva Versteijne
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
| | - Geertjan van Tienhoven
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands
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Yu S, Lawrenson L, Wei R, Sehgal V, Hanna N, Kuo J, Daroui P, Ramsinghani N, Al-Ghazi M. The dosimetric impact of image guided radiation therapy by intratumoral fiducial markers. Pract Radiat Oncol 2016; 6:276-283. [DOI: 10.1016/j.prro.2015.11.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Revised: 11/06/2015] [Accepted: 11/11/2015] [Indexed: 02/06/2023]
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Houweling AC, Fukata K, Kubota Y, Shimada H, Rasch CR, Ohno T, Bel A, van der Horst A. The impact of interfractional anatomical changes on the accumulated dose in carbon ion therapy of pancreatic cancer patients. Radiother Oncol 2016; 119:319-25. [DOI: 10.1016/j.radonc.2016.03.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Revised: 02/23/2016] [Accepted: 03/04/2016] [Indexed: 01/17/2023]
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45
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Huijskens SC, van Dijk IW, de Jong R, Visser J, Fajardo RD, Ronckers CM, Janssens GO, Maduro JH, Rasch CR, Alderliesten T, Bel A. Quantification of renal and diaphragmatic interfractional motion in pediatric image-guided radiation therapy: A multicenter study. Radiother Oncol 2015; 117:425-31. [DOI: 10.1016/j.radonc.2015.09.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Revised: 08/31/2015] [Accepted: 09/17/2015] [Indexed: 10/23/2022]
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Lischalk JW, Kole TP, Anjum HM, Obayomi-Davies O, Rashid A, Unger K. Four-dimensional computed tomography prediction of inter- and intrafractional upper gastrointestinal tumor motion during fractionated stereotactic body radiation therapy. Pract Radiat Oncol 2015; 6:176-182. [PMID: 26746816 DOI: 10.1016/j.prro.2015.10.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 09/25/2015] [Accepted: 10/08/2015] [Indexed: 12/25/2022]
Abstract
PURPOSE Respiratory-induced tumor motion of upper gastrointestinal (GI) tumors during radiation therapy is often assessed using a single 4-dimensional computed tomography (4D-CT) and presumed to be representative during fractionated treatment regimens. The purpose of this study was to examine the intra- and interfraction correlations of tumor motion between pretreatment 4D-CT and real-time fiducial-based motion tracking in patients treated with fractionated stereotactic body radiation therapy (SBRT) for upper GI malignancies. METHODS AND MATERIALS Fourteen patients with upper GI tumors underwent fractionated SBRT using the CyberKnife radiosurgical system with Synchrony respiratory motion management. Before treatment, each patient underwent a free-breathing 4D-CT scan and fiducial motion was tracked for each phase of the respiratory cycle. Real-time fiducial positions recorded during delivery of each SBRT fraction were extracted from the CyberKnife planning system. Displacements were compared between those predicted by 4D-CT and those recorded by Synchrony during treatment in the left-right (LR), anteroposterior (AP), and superoinferior (SI) directions. RESULTS The 4D-CT scans demonstrated little correlation with real-time mean fiducial displacement as determined by Pearson correlation with coefficients of 0.45, 0.52, and 0.63 in the SI, AP, and LR directions, respectively. Cohort-averaged maximum fiducial displacements based on 4D-CT and real-time tracking were measured to be 3.86 ± 1.40 mm versus 10.73 ± 7.03 mm, 2.29 ± 1.02 mm versus 4.44 ± 3.33 mm, and 1.45 ± 0.49 mm versus 2.67 ± 2.49 mm in the SI, AP, and LR directions, respectively. Mean fiducial displacements were greater than that predicted by the maximum displacements on the corresponding 4D-CT scan in 39%, 22%, and 25% of SBRT fractions in the SI, AP, and LR directions, respectively. CONCLUSIONS Comparison of 4D-CT with real-time fiducial tracking demonstrated significant inter- and intrafractional discrepancies, particularly in the SI direction, which could result in compromise of target coverage when planning with a single free-breathing 4D-CT.
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Affiliation(s)
- Jonathan W Lischalk
- Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Washington, DC.
| | - Thomas P Kole
- Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Washington, DC
| | - Hozaifa M Anjum
- Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Washington, DC
| | - Olusola Obayomi-Davies
- Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Washington, DC
| | - Abdul Rashid
- Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Washington, DC
| | - Keith Unger
- Department of Radiation Medicine, Lombardi Comprehensive Cancer Center, Georgetown University Hospital, Washington, DC
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Jin P, van der Horst A, de Jong R, van Hooft JE, Kamphuis M, van Wieringen N, Machiels M, Bel A, Hulshof MCCM, Alderliesten T. Marker-based quantification of interfractional tumor position variation and the use of markers for setup verification in radiation therapy for esophageal cancer. Radiother Oncol 2015; 117:412-8. [PMID: 26475250 DOI: 10.1016/j.radonc.2015.10.005] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2015] [Revised: 09/30/2015] [Accepted: 10/04/2015] [Indexed: 12/20/2022]
Abstract
PURPOSE The aim of this study was to quantify interfractional esophageal tumor position variation using markers and investigate the use of markers for setup verification. MATERIALS AND METHODS Sixty-five markers placed in the tumor volumes of 24 esophageal cancer patients were identified in computed tomography (CT) and follow-up cone-beam CT. For each patient we calculated pairwise distances between markers over time to evaluate geometric tumor volume variation. We then quantified marker displacements relative to bony anatomy and estimated the variation of systematic (Σ) and random errors (σ). During bony anatomy-based setup verification, we visually inspected whether the markers were inside the planning target volume (PTV) and attempted marker-based registration. RESULTS Minor time trends with substantial fluctuations in pairwise distances implied tissue deformation. Overall, Σ(σ) in the left-right/cranial-caudal/anterior-posterior direction was 2.9(2.4)/4.1(2.4)/2.2(1.8) mm; for the proximal stomach, it was 5.4(4.3)/4.9(3.2)/1.9(2.4) mm. After bony anatomy-based setup correction, all markers were inside the PTV. However, due to large tissue deformation, marker-based registration was not feasible. CONCLUSIONS Generally, the interfractional position variation of esophageal tumors is more pronounced in the cranial-caudal direction and in the proximal stomach. Currently, marker-based setup verification is not feasible for clinical routine use, but markers can facilitate the setup verification by inspecting whether the PTV covers the tumor volume adequately.
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Affiliation(s)
- Peng Jin
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, The Netherlands.
| | - Astrid van der Horst
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Rianne de Jong
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Jeanin E van Hooft
- Department of Gastroenterology and Hepatology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Martijn Kamphuis
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Niek van Wieringen
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Melanie Machiels
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Arjan Bel
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Maarten C C M Hulshof
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, The Netherlands
| | - Tanja Alderliesten
- Department of Radiation Oncology, Academic Medical Center, University of Amsterdam, The Netherlands
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Alonzi R. Functional Radiotherapy Targeting using Focused Dose Escalation. Clin Oncol (R Coll Radiol) 2015; 27:601-17. [PMID: 26456478 DOI: 10.1016/j.clon.2015.06.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2015] [Accepted: 06/17/2015] [Indexed: 12/12/2022]
Abstract
Various quantitative and semi-quantitative imaging biomarkers have been identified that may serve as valid surrogates for the risk of recurrence after radiotherapy. Tumour characteristics, such as hypoxia, vascularity, cellular proliferation and clonogen density, can be geographically mapped using biological imaging techniques. The potential gains in therapeutic ratio from the precision targeting of areas of intrinsic resistance makes focused dose escalation an exciting field of study. This overview will explore the issues surrounding biologically optimised radiotherapy, including its requirements, feasibility, technical considerations and potential applicability.
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Affiliation(s)
- R Alonzi
- Mount Vernon Cancer Centre, Northwood, UK.
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49
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Lens E, van der Horst A, Versteijne E, van Tienhoven G, Bel A. Dosimetric Advantages of Midventilation Compared With Internal Target Volume for Radiation Therapy of Pancreatic Cancer. Int J Radiat Oncol Biol Phys 2015; 92:675-82. [DOI: 10.1016/j.ijrobp.2015.02.015] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Revised: 02/05/2015] [Accepted: 02/09/2015] [Indexed: 01/18/2023]
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50
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van Zweeden AA, van der Vliet HJ, Wilmink JW, Meijerink MR, Meijer OWM, Bruynzeel AME, van Tienhoven G, Giovannetti E, Kazemier G, Jacobs MAJM, Verheul HMW. Phase I Clinical Trial to Determine the Feasibility and Maximum Tolerated Dose of Panitumumab to Standard Gemcitabine-Based Chemoradiation in Locally Advanced Pancreatic Cancer. Clin Cancer Res 2015; 21:4569-75. [PMID: 26056353 DOI: 10.1158/1078-0432.ccr-14-3364] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2014] [Accepted: 06/01/2015] [Indexed: 11/16/2022]
Abstract
PURPOSE Epidermal growth factor receptor (EGFR) inhibitors may improve both the therapeutic efficacy of radiotherapy and the radiosensitizing activity of gemcitabine. Based on this rationale and the nonoverlapping toxicity profiles of gemcitabine and the monoclonal EGFR antibody panitumumab, we designed a phase I trial to investigate the maximum-tolerated dose (MTD), safety, and activity of panitumumab added to gemcitabine-based chemoradiotherapy (CRT) in patients with locally advanced pancreatic cancer (LAPC). EXPERIMENTAL DESIGN Patients with LAPC and WHO performance status 0 to 1 were treated with weekly panitumumab at four dose levels (1-2.5 mg/kg), combined with weekly gemcitabine 300 mg/m(2) and radiotherapy (50.4 Gy in 28 fractions) for 6 weeks, followed by gemcitabine 1,000 mg/m(2) weekly for 3 weeks every 4 weeks until disease progression or unacceptable toxicity. Each cohort was monitored during the combination therapy to establish dose limiting toxicity. Tumor evaluation was performed after CRT and during gemcitabine monotherapy. RESULTS Fourteen patients were enrolled; 14 were evaluable for toxicity and 13 for response. The MTD for panitumumab was 1.5 mg/kg. Three of the 6 patients, treated at MTD, experienced grade 3 adverse events during the combination therapy; neutropenia (n = 2; 33%), fatigue (n = 1; 17%), nausea (n = 1; 17%), and vomiting (n = 1; 17%). Partial response was achieved by 3 patients (23%), 1 in each dose cohort. Median progression free survival of the three cohorts together was 8.9 months. CONCLUSIONS The addition of panitumumab to gemcitabine-based chemoradiotherapy in LAPC has manageable toxicity and potential clinical efficacy.
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Affiliation(s)
- Annette A van Zweeden
- Department of Medical Oncology, VU University Medical Center, Amsterdam, the Netherlands
| | - Hans J van der Vliet
- Department of Medical Oncology, VU University Medical Center, Amsterdam, the Netherlands
| | - Johanna W Wilmink
- Department of Medical Oncology, Academic Medical Center, Amsterdam, the Netherlands
| | - Martijn R Meijerink
- Department of Radiology and Nuclear Medicine, VU University Medical Center, Amsterdam, the Netherlands
| | - Otto W M Meijer
- Department of Radiation Oncology, VU University Medical Center, Amsterdam, the Netherlands
| | - Anna M E Bruynzeel
- Department of Radiation Oncology, VU University Medical Center, Amsterdam, the Netherlands
| | | | - Elisa Giovannetti
- Department of Medical Oncology, VU University Medical Center, Amsterdam, the Netherlands
| | - Geert Kazemier
- Department of Surgery, VU University Medical Center, Amsterdam, the Netherlands
| | - Maarten A J M Jacobs
- Department of Gastroenterology and Hepatology, VU University Medical Center, Amsterdam, the Netherlands
| | - Henk M W Verheul
- Department of Medical Oncology, VU University Medical Center, Amsterdam, the Netherlands.
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