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Weiß A, Löck S, Xu T, Liao Z, Hoffmann AL, Troost EGC. Prediction of radiation pneumonitis using the effective α/β of lungs and heart in NSCLC patients treated with proton beam therapy. Radiother Oncol 2024; 190:110013. [PMID: 37972734 DOI: 10.1016/j.radonc.2023.110013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/08/2023] [Accepted: 11/09/2023] [Indexed: 11/19/2023]
Abstract
PURPOSE Radiation pneumonitis (RP) remains a major complication in non-small cell lung cancer (NSCLC) patients undergoing radiochemotherapy (RCHT). Traditionally, the mean lung dose (MLD) and the volume of the total lung receiving at least 20 Gy (V20Gy) are used to predict RP in patients treated with normo-fractionated photon therapy. However, other models, including the actual dose-distribution in the lungs using the effective α/β model or a combination of radiation doses to the lungs and heart, have been proposed for predicting RP. Moreover, the models established for photons may not hold for patients treated with passively-scattered proton therapy (PSPT). Therefore, we here tested and validated novel predictive parameters for RP in NSCLC patient treated with PSPT. METHODS Data on the occurrence of RP, structure files and dose-volume histogram parameters for lungs and heart of 96 NSCLC patients, treated with PSPT and concurrent chemotherapy, was retrospectively retrieved from prospective clinical studies of two international centers. Data was randomly split into a training set (64 patients) and a validation set (32 patients). Statistical analyses were performed using binomial logistic regression. RESULTS The biologically effective dose (BED) of the'lungs - GTV' significantly predicted RP ≥ grade 2 in the training-set using both a univariate model (p = 0.019, AUCtrain = 0.72) and a multivariate model in combination with the effective α/β parameter of the heart (pBED = 0.006, [Formula: see text] = 0.043, AUCtrain = 0.74). However, these results did not hold in the validation-set (AUCval = 0.52 andAUCval = 0.50, respectively). Moreover, these models were found to neither outperform a model built with the MLD (p = 0.015, AUCtrain = 0.73, AUCval = 0.51), nor a multivariate model additionally including the V20Gy of the heart (pMLD = 0.039, pV20Gy,heart = 0.58, AUCtrain = 0.74, AUCval = 0.53). CONCLUSION Using the effective α/β parameter of the lungs and heart we achieved similar performance to commonly used models built for photon therapy, such as MLD, in predicting RP ≥ grade 2. Therefore, prediction models developed for photon RCHT still hold for patients treated with PSPT.
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Affiliation(s)
- Albrecht Weiß
- German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, 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, Dresden, Germany
| | - Steffen Löck
- German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, 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, Dresden, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Ting Xu
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Zhongxing Liao
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - Aswin L Hoffmann
- OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, 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; Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology-OncoRay, Dresden, Germany
| | - Esther G C Troost
- German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, 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, Dresden, Germany; Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, 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, Dresden, Germany, Helmholtz Association/Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Dresden, Germany; Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology-OncoRay, Dresden, Germany.
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Schneider S, Stefanowicz S, Jentsch C, Lohaus F, Thiele J, Haak D, Valentini C, Platzek I, G. C. Troost E, Hoffmann AL. Reduction of intrafraction pancreas motion using an abdominal corset compatible with proton therapy and MRI. Clin Transl Radiat Oncol 2022; 38:111-116. [DOI: 10.1016/j.ctro.2022.11.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 11/07/2022] [Accepted: 11/07/2022] [Indexed: 11/11/2022] Open
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Gantz S, Schellhammer SM, Hoffmann AL. Image Performance Characterization of an In-Beam Low-Field Magnetic Resonance Imaging System During Static Proton Beam Irradiation. IEEE Trans Radiat Plasma Med Sci 2022. [DOI: 10.1109/trpms.2021.3085991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Gillmann C, Homolka N, Johnen W, Runz A, Echner G, Pfaffenberger A, Mann P, Schneider V, Hoffmann AL, Troost EGC, Koerber SA, Kotzerke J, Beuthien-Baumann B. Technical Note: ADAM PETer - An anthropomorphic, deformable and multimodality pelvis phantom with positron emission tomography extension for radiotherapy. Med Phys 2020; 48:1624-1632. [PMID: 33207020 DOI: 10.1002/mp.14597] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 09/10/2020] [Accepted: 10/29/2020] [Indexed: 01/19/2023] Open
Abstract
OBJECTIVE To develop an anthropomorphic, deformable and multimodal pelvis phantom with positron emission tomography extension for radiotherapy (ADAM PETer). METHODS The design of ADAM PETer was based on our previous pelvis phantom (ADAM) and extended for compatibility with PET and use in 3T magnetic resonance imaging (MRI). The formerly manually manufactured silicon organ surrogates were replaced by three-dimensional (3D) printed organ shells. Two intraprostatic lesions, four iliac lymph node metastases and two pelvic bone metastases were added to simulate prostate cancer as multifocal and metastatic disease. Radiological properties [computed tomography (CT) and 3T MRI] of cortical bone, bone marrow and adipose tissue were simulated by heavy gypsum, a mixture of Vaseline and K2 HPO4 and peanut oil, respectively. For soft tissues, agarose gels with varying concentrations of agarose, gadolinium (Gd) and sodium fluoride (NaF) were developed. The agarose gels were doped with patient-specific activity concentrations of a Fluorine-18 labelled compound and then filled into the 3D printed organ shells of prostate lesions, lymph node and bone metastases. The phantom was imaged at a dual energy CT and a 3T PET/MRI scanner. RESULTS The compositions of the soft tissue surrogates are the following (given as mass fractions of agarose[w%]/NaF[w%]/Gd[w%]): Muscle (4/1/0.027), prostate (1.35/4.2/0.011), prostate lesions (2.25/4.2/0.0085), lymph node and bone metastases (1.4/4.2/0.025). In all imaging modalities, the phantom simulates human contrast. Intraprostatic lesions appear hypointense as compared to the surrounding normal prostate tissue in T2-weighted MRI. The PET signal of all tumors can be localized as focal spots at their respective site. Activity concentrations of 12.0 kBq/mL (prostate lesion), 12.4 kBq/mL (lymph nodes) and 39.5 kBq/mL (bone metastases) were measured. CONCLUSION The ADAM PETer pelvis phantom can be used as multimodal, anthropomorphic model for CT, 3T-MRI and PET measurements. It will be central to simulate and optimize the technical workflow for the integration of PET/MRI-based radiation treatment planning of prostate cancer patients.
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Affiliation(s)
- Clarissa Gillmann
- German Cancer Research Center (DKFZ), Department of Medical Physics in Radiation Oncology, Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Noa Homolka
- German Cancer Research Center (DKFZ), Department of Medical Physics in Radiation Oncology, Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,Faculty for Physics and Astronomy, University of Heidelberg, Heidelberg, Germany
| | - Wibke Johnen
- German Cancer Research Center (DKFZ), Department of Medical Physics in Radiation Oncology, Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Armin Runz
- German Cancer Research Center (DKFZ), Department of Medical Physics in Radiation Oncology, Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Gernot Echner
- German Cancer Research Center (DKFZ), Department of Medical Physics in Radiation Oncology, Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Asja Pfaffenberger
- German Cancer Research Center (DKFZ), Department of Medical Physics in Radiation Oncology, Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Philipp Mann
- German Cancer Research Center (DKFZ), Department of Medical Physics in Radiation Oncology, Heidelberg, Germany.,Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany
| | - Verena Schneider
- Department of Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany
| | - Aswin L Hoffmann
- OncoRay - National Center for Radiation Research in Oncology, University Hospital Carl Gustav Carus Dresden, Dresden, Germany.,Department for Radiotherapy and Radiation Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus Dresden, Dresden, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany
| | - Esther G C Troost
- OncoRay - National Center for Radiation Research in Oncology, University Hospital Carl Gustav Carus Dresden, Dresden, Germany.,Department for Radiotherapy and Radiation Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus Dresden, Dresden, Germany.,Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, Dresden, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, Dresden, Germany.,National Center for Tumor Diseases (NCT), Partner Site Dresden, Germany
| | - Stefan A Koerber
- Heidelberg Institute for Radiation Oncology (HIRO), National Center for Radiation Research in Oncology (NCRO), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), Partner Site, Heidelberg, Germany.,Department of Radiation Oncology, University Hospital Heidelberg, Heidelberg, Germany
| | - Jörg Kotzerke
- Department for Radiotherapy and Radiation Oncology, Faculty of Medicine, University Hospital Carl Gustav Carus Dresden, Dresden, Germany.,Department for Nuclear Medicine, University Hospital Carl Gustav Carus, Dresden, Germany
| | - Bettina Beuthien-Baumann
- Department of Radiology, German Cancer Research Center (DKFZ), Heidelberg, Germany.,National Center for Tumor Diseases (NCT), Partner Site, Heidelberg, Germany
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Taeubert L, Berker Y, Beuthien-Baumann B, Hoffmann AL, Troost EGC, Kachelrieß M, Gillmann C. CT-based attenuation correction of whole-body radiotherapy treatment positioning devices in PET/MRI hybrid imaging. ACTA ACUST UNITED AC 2020; 65:23NT02. [DOI: 10.1088/1361-6560/abb7c3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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H. Morris R, R. Geraldi N, C. Pike L, Pawelke J, L. Hoffmann A, Doy N, L. Stafford J, Spicer A, I. Newton M. Advanced Sandwich Composite Cores for Patient Support in Advanced Clinical Imaging and Oncology Treatment. Materials (Basel) 2020; 13:ma13163549. [PMID: 32806610 PMCID: PMC7475909 DOI: 10.3390/ma13163549] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 07/29/2020] [Accepted: 08/04/2020] [Indexed: 01/18/2023]
Abstract
Ongoing advances in both imaging and treatment for oncology purposes have seen a significant rise in the use of not only the individual imaging modalities, but also their combination in single systems such as Positron Emission Tomography combined with Computed Tomography (PET–CT) and PET–MRI (Magnetic Resonance Imaging) when planning for advanced oncology treatment, the most demanding of which is proton therapy. This has identified issues in the availability of suitable materials upon which to support the patient undergoing imaging and treatment owing to the differing requirements for each of the techniques. Sandwich composites are often selected to solve this issue but there is little information regarding optimum materials for their cores. In this paper, we presented a range of materials which are suitable for such purposes and evaluated the performance for use in terms of PET signal attenuation, proton beam stopping, MRI signal shading and X-Ray CT visibility. We found that Extruded Polystyrene offers the best compromise for patient support and positioning structures across all modalities tested, allowing for significant savings in treatment planning time and delivering more efficient treatment with lower margins.
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Affiliation(s)
- Robert H. Morris
- School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UK; (N.R.G.); (N.D.); (J.L.S.); (A.S.); (M.I.N.)
- Correspondence:
| | - Nicasio R. Geraldi
- School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UK; (N.R.G.); (N.D.); (J.L.S.); (A.S.); (M.I.N.)
| | - Lucy C. Pike
- King’s College London and Guy’s and St Thomas’ PET Centre, School of Biomedical Engineering & Imaging Sciences, King’s College London, King’s Health Partners, St Thomas’ Hospital, London SE1 7EH, UK;
| | - Jörg Pawelke
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, 01307 Dresden, Germany; (J.P.); (A.L.H.)
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology-OncoRay, 01328 Dresden, Germany
| | - Aswin L. Hoffmann
- OncoRay—National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, 01307 Dresden, Germany; (J.P.); (A.L.H.)
- Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology-OncoRay, 01328 Dresden, Germany
| | - Nicola Doy
- School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UK; (N.R.G.); (N.D.); (J.L.S.); (A.S.); (M.I.N.)
| | - Johanna L. Stafford
- School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UK; (N.R.G.); (N.D.); (J.L.S.); (A.S.); (M.I.N.)
| | - Abi Spicer
- School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UK; (N.R.G.); (N.D.); (J.L.S.); (A.S.); (M.I.N.)
| | - Michael I. Newton
- School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NS, UK; (N.R.G.); (N.D.); (J.L.S.); (A.S.); (M.I.N.)
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Causer TJ, Schellhammer SM, Gantz S, Lühr A, Hoffmann AL, Metcalfe PE, Rosenfeld AB, Guatelli S, Petasecca M, Oborn BM. First application of a high-resolution silicon detector for proton beam Bragg peak detection in a 0.95 T magnetic field. Med Phys 2019; 47:181-189. [PMID: 31621914 DOI: 10.1002/mp.13871] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2019] [Revised: 10/09/2019] [Accepted: 10/10/2019] [Indexed: 11/12/2022] Open
Abstract
PURPOSE To report on experimental results of a high spatial resolution silicon-based detector exposed to therapeutic quality proton beams in a 0.95 T transverse magnetic field. These experimental results are important for the development of accurate and novel dosimetry methods in future potential real-time MRI-guided proton therapy systems. METHODS A permanent magnet device was utilized to generate a 0.95 T magnetic field over a 4 × 20 × 15 cm3 volume. Within this volume, a high-resolution silicon diode array detector was positioned inside a PMMA phantom of 4 × 15 × 12 cm3 . This detector contains two orthogonal strips containing 505 sensitive volumes spaced at 0.2 mm apart. Proton beams collimated to a circle of 10 mm diameter with nominal energies of 90 MeV, 110 MeV, and 125 MeV were incident on the detector from an edge-on orientation. This allows for a measurement of the Bragg peak at 0.2 mm spatial resolution in both the depth and lateral profile directions. The impact of the magnetic field on the proton beams, that is, a small deflection was also investigated. A Geant4 Monte Carlo simulation was performed of the experimental setup to aid in interpretation of the results. RESULTS The nominal Bragg peak for each proton energy was successfully observed with a 0.2 mm spatial resolution in the 0.95 T transverse magnetic field in both a depth and lateral profiles. The proton beam deflection (at 0.95 T) was a consistent 2 ±0.5 mm at the center of the magnetic volume for each beam energy. However, a pristine Bragg peak was not observed for each energy. This was caused by the detector packaging having small air gaps between layers of the phantom material surrounding the diode array. These air gaps act to degrade the shape of the Bragg peak, and further to this, the nonwater equivalent silicon chip acts to separate the Bragg peak into multiple peaks depending on the proton path taken. Overall, a promising performance of the silicon detector array was observed, however, with a qualitative assessment rather than a robust quantitative dosimetric evaluation at this stage of development. CONCLUSIONS For the first time, a high-resolution silicon-based radiation detector has been used to measure proton beam Bragg peak deflections in a phantom due to a strong magnetic field. Future efforts are required to optimize the detector packaging to strengthen the robustness of the dosimetric quantities obtained from the detector. Such high-resolution silicon diode arrays may be useful in future efforts in MRI-guided proton therapy research.
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Affiliation(s)
- Trent J Causer
- Illawarra Cancer Care Centre, Wollongong, NSW, 2500, Australia.,Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, 2500, Australia
| | - Sonja M Schellhammer
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology, Dresden, Germany.,OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universitt Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Sebastian Gantz
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology, Dresden, Germany.,OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universitt Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany
| | - Armin Lühr
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology, Dresden, Germany.,OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universitt Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,German Cancer Consortium DKTK, Partner Site Dresden, Dresden, Germany
| | - Aswin L Hoffmann
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology, Dresden, Germany.,OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universitt Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, Germany.,Dept. of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus at the Technische Universitat Dresden, Dresden, Germany
| | - Peter E Metcalfe
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, 2500, Australia.,Ingham Institute for Applied Medical Research, Liverpool, NSW, 2170, Australia
| | - Anatoly B Rosenfeld
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, 2500, Australia
| | - Susanna Guatelli
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, 2500, Australia
| | - Marco Petasecca
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, 2500, Australia
| | - Bradley M Oborn
- Illawarra Cancer Care Centre, Wollongong, NSW, 2500, Australia.,Centre for Medical Radiation Physics, University of Wollongong, Wollongong, NSW, 2500, Australia
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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] [What about the content of this article? (0)] [Affiliation(s)] [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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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] [What about the content of this article? (0)] [Affiliation(s)] [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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10
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Lühr A, Burigo LN, Gantz S, Schellhammer SM, Hoffmann AL. Proton beam electron return effect: Monte Carlo simulations and experimental verification. Phys Med Biol 2019; 64:035012. [PMID: 30577039 DOI: 10.1088/1361-6560/aafab4] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Proton therapy (PT) is expected to benefit from integration with magnetic resonance (MR) imaging. However, the magnetic field distorts the dose distribution and enhances the dose at tissue-air interfaces by the electron return effect (ERE). The objectives were (a) to provide experimental evidence for the ERE in proton beams and (b) to systematically characterise the dependence of the dose enhancement ratio (DER) on magnetic field strength, orientation, proton energy and voxel size by computer simulations. EBT3 films were irradiated with 200 MeV protons with and without a 0.92 T transverse field of a permanent magnet to determine the DER at effective measurement depths of 0.156 and 0.467 mm from an air interface. High-resolution Monte Carlo simulations were performed to reproduce the irradiation experiments and to calculate the DER for proton energies between 50-200 MeV and magnetic field strengths between 0.35-3 T as function of distance from the air interface. Voxel sizes of 0.05, 0.5 and 1 mm were analysed. DERs of (2.2 ± 0.4)% and (0.5 ± 0.6)% were measured at 0.156 and 0.467 mm from the air interface, respectively. Measurements and simulations agreed within 0.15%. For a 200 MeV proton beam, the maximum DER in 0.05 mm voxels increased with magnetic field strength from 2.6% to 8.2% between 0.35 and 1.5 T, respectively. For a 1.0 T magnetic field, maximum DER increased from 3.2% to 7.6% between 50 and 200 MeV, respectively. Voxel sizes of 0.5 and 1 mm resulted in maximum DER values of 2.6% and 1.4%, respectively. The ERE for proton beams in transverse magnetic fields is measurable. The local dose enhancement is significant, well predictable, decreases rapidly with distance from the air interface, and is negligible beyond 1 mm depth. Its impact on air-filled ionisation chambers and porous tissues (e.g. lung) needs to be considered.
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Affiliation(s)
- A Lühr
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Radiooncology - OncoRay, 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, Dresden, Germany. German Cancer Consortium (DKTK), Partner Site Dresden, Dresden, Germany. Both authors contributed equally to this work. Author to whom any correspondence should be addressed
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11
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Peerlings J, Compter I, Janssen F, Wiggins CJ, Postma AA, Mottaghy FM, Lambin P, Hoffmann AL. Characterizing geometrical accuracy in clinically optimised 7T and 3T magnetic resonance images for high-precision radiation treatment of brain tumours. Phys Imaging Radiat Oncol 2019; 9:35-42. [PMID: 33458423 PMCID: PMC7807620 DOI: 10.1016/j.phro.2018.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/29/2018] [Revised: 11/23/2018] [Accepted: 12/05/2018] [Indexed: 11/27/2022]
Abstract
Background and purpose In neuro-oncology, high spatial accuracy is needed for clinically acceptable high-precision radiation treatment planning (RTP). In this study, the clinical applicability of anatomically optimised 7-Tesla (7T) MR images for reliable RTP is assessed with respect to standard clinical imaging modalities. Materials and methods System- and phantom-related geometrical distortion (GD) were quantified on clinically-relevant MR sequences at 7T and 3T, and on CT images using a dedicated anthropomorphic head phantom incorporating a 3D grid-structure, creating 436 points-of-interest. Global GD was assessed by mean absolute deviation (MADGlobal). Local GD relative to the magnetic isocentre was assessed by MADLocal. Using 3D displacement vectors of individual points-of-interest, GD maps were created. For clinically acceptable radiotherapy, 7T images need to meet the criteria for accurate dose delivery (GD < 1 mm) and present comparable GD as tolerated in clinically standard 3T MR/CT-based RTP. Results MADGlobal in 7T and 3T images ranged from 0.3 to 2.2 mm and 0.2-0.8 mm, respectively. MADLocal increased with increasing distance from the isocentre, showed an anisotropic distribution, and was significantly larger in 7T MR sequences (MADLocal = 0.2-1.2 mm) than in 3T (MADLocal = 0.1-0.7 mm) (p < 0.05). Significant differences in GD were detected between 7T images (p < 0.001). However, maximum MADLocal remained ≤1 mm within 68.7 mm diameter spherical volume. No significant differences in GD were found between 7T and 3T protocols near the isocentre. Conclusions System- and phantom-related GD remained ≤1 mm in central brain regions, suggesting that 7T MR images could be implemented in radiotherapy with clinically acceptable spatial accuracy and equally tolerated GD as in 3T MR/CT-based RTP. For peripheral regions, GD should be incorporated in safety margins for treatment uncertainties. Moreover, the effects of sequence-related factors on GD needs further investigation to obtain RTP-specific MR protocols.
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Affiliation(s)
- Jurgen Peerlings
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre+, Maastricht, The Netherlands.,Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Inge Compter
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Fiere Janssen
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | | | - Alida A Postma
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Felix M Mottaghy
- Department of Radiology and Nuclear Medicine, Maastricht University Medical Centre+, Maastricht, The Netherlands.,Department of Nuclear Medicine, University Hospital RWTH Aachen University, Aachen, Germany
| | - Philippe Lambin
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Aswin L Hoffmann
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Centre+, Maastricht, The Netherlands.,Institute of Radiooncology, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,OncoRay National Center for Radiation Research in Oncology, Dresden, Germany.,Department of Radiotherapy, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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12
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Vanneste BG, Buettner F, Pinkawa M, Lambin P, Hoffmann AL. Ano-rectal wall dose-surface maps localize the dosimetric benefit of hydrogel rectum spacers in prostate cancer radiotherapy. Clin Transl Radiat Oncol 2019; 14:17-24. [PMID: 30456317 PMCID: PMC6234617 DOI: 10.1016/j.ctro.2018.10.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 10/31/2018] [Accepted: 10/31/2018] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND AND PURPOSE To evaluate spatial differences in dose distributions of the ano-rectal wall (ARW) using dose-surface maps (DSMs) between prostate cancer patients receiving intensity-modulated radiation therapy with and without implantable rectum spacer (IMRT+IRS; IMRT-IRS, respectively), and to correlate this with late gastro-intestinal (GI) toxicities using validated spatial and non-spatial normal-tissue complication probability (NTCP) models. MATERIALS AND METHODS For 26 patients DSMs of the ARW were generated. From the DSMs various shape-based dose measures were calculated at different dose levels: lateral extent, longitudinal extent, and eccentricity. The contiguity of the ARW dose distribution was assessed by the contiguous-DSH (cDSH). Predicted complication rates between IMRT+IRS and IMRT-IRS plans were assessed using a spatial NTCP model and compared against a non-spatial NTCP model. RESULTS Dose surface maps are generated for prostate radiotherapy using an IRS. Lateral extent, longitudinal extent and cDSH were significantly lower in IMRT+IRS than for IMRT-IRS at high-dose levels. Largest significant differences were observed for cDSH at dose levels >50 Gy, followed by lateral extent at doses >57 Gy, and longitudinal extent in anterior and superior-inferior directions. Significant decreases (p = 0.01) in median rectal and anal NTCPs (respectively, Gr 2 late rectal bleeding and subjective sphincter control) were predicted when using an IRS. CONCLUSIONS Local-dose effects are predicted to be significantly reduced by an IRS. The spatial NTCP model predicts a significant decrease in Gr 2 late rectal bleeding and subjective sphincter control. Dose constraints can be improved for current clinical treatment planning.
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Affiliation(s)
| | | | - Michael Pinkawa
- Department of Radiation Oncology, MediClin Robert Janker Klinik, Bonn, Germany
| | - Philippe Lambin
- The D-Lab, GROW – School for Oncology and Developmental Biology, Maastricht University Medical Centre+, Maastricht, The Netherlands
| | - Aswin L. Hoffmann
- MAASTRO Clinic, Maastricht, The Netherlands
- Institute of Radiooncology, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
- Department of Radiotherapy, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Dresden, Germany
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13
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Schellhammer SM, Hoffmann AL, Gantz S, Smeets J, van der Kraaij E, Quets S, Pieck S, Karsch L, Pawelke J. Integrating a low-field open MR scanner with a static proton research beam line: proof of concept. Phys Med Biol 2018; 63:23LT01. [PMID: 30465549 DOI: 10.1088/1361-6560/aaece8] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
On-line image guidance using magnetic resonance (MR) imaging is expected to improve the targeting accuracy of proton therapy. However, to date no combined system exists. In this study, for the first time a low-field open MR scanner was integrated with a static proton research beam line to test the feasibility of simultaneous irradiation and imaging. The field-of-view of the MR scanner was aligned with the beam by taking into account the Lorentz force induced beam deflection. Various imaging sequences for extremities were performed on a healthy volunteer and on a patient with a soft-tissue sarcoma of the upper arm, both with the proton beam line switched off. T 1-weighted spin echo images of a tissue-mimicking phantom were acquired without beam, with energised beam line magnets and during proton irradiation. Beam profiles were acquired for the MR scanner's static magnetic field alone and in combination with the dynamic gradient fields during the acquisition of different imaging sequences. It was shown that MR imaging is feasible in the electromagnetically contaminated environment of a proton therapy facility. The observed quality of the anatomical MR images was rated to be sufficient for target volume definition and positioning. The tissue-mimicking phantom showed no visible beam-induced image degradation. The beam profiles depicted no influence due to the dynamic gradient fields of the imaging sequences. This study proves that simultaneous irradiation and in-beam MR imaging is technically feasible with a low-field MR scanner integrated with a static proton research beam line.
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Affiliation(s)
- Sonja M Schellhammer
- OncoRay-National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany. Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiooncology-OncoRay, Dresden, Germany. Both authors contributed equally to this work
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14
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Schellhammer SM, Gantz S, Lühr A, Oborn BM, Bussmann M, Hoffmann AL. Technical Note: Experimental verification of magnetic field-induced beam deflection and Bragg peak displacement for MR-integrated proton therapy. Med Phys 2018; 45:3429-3434. [PMID: 29763970 DOI: 10.1002/mp.12961] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Revised: 03/26/2018] [Accepted: 04/16/2018] [Indexed: 11/10/2022] Open
Abstract
PURPOSE Given its sensitivity to anatomical variations, proton therapy is expected to benefit greatly from integration with magnetic resonance imaging for online anatomy monitoring during irradiation. Such an integration raises several challenges, as both systems mutually interact. The proton beam will experience quasi-continuous energy loss and energy-dependent electromagnetic deflection at the same time, giving rise to a deflected beam trajectory and an altered dose distribution with a displaced Bragg peak. So far, these effects have only been predicted using Monte Carlo and analytical models, but no clear consensus has been reached and experimental benchmark data are lacking. We measured proton beam trajectories and Bragg peak displacement in a homogeneous phantom placed inside a magnetic field and compared them to simulations. METHODS Planar dose distributions of proton pencil beams (80-180 MeV) traversing the field of a 0.95 T NdFeB permanent magnet while depositing energy in a PMMA slab phantom were measured using EBT3 radiochromic films and simulated using the Geant4 toolkit. Deflected beam trajectories and the Bragg peak displacement were extracted from the measured planar dose distributions and compared against the simulations. RESULTS The lateral beam deflection was clearly visible on the EBT3 films and ranged from 1 to 10 mm for 80 to 180 MeV, respectively. Simulated and measured beam trajectories and Bragg peak displacement agreed within 0.8 mm for all studied proton energies. CONCLUSIONS These results prove that the magnetic field-induced Bragg peak displacement is both measurable and accurately predictable in a homogeneous phantom at 0.95 T, and allows Monte Carlo simulations to be used as gold standard for proton beam trajectory prediction in similar frameworks for MR-integrated proton therapy.
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Affiliation(s)
- Sonja M Schellhammer
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, 01307, Germany.,Institute of Radiooncology - OncoRay, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, 01328, Germany
| | - Sebastian Gantz
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, 01307, Germany.,Institute of Radiooncology - OncoRay, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, 01328, Germany
| | - Armin Lühr
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, 01307, Germany.,Institute of Radiooncology - OncoRay, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, 01328, Germany.,German Cancer Consortium (DKTK), Partner Site Dresden, and German Cancer Research Center (DKFZ), Heidelberg, 69120, Germany
| | - Bradley M Oborn
- Centre for Medical Radiation Physics, University of Wollongong, Wollongong, 2522, Australia.,Illawarra Cancer Care Centre, Wollongong Hospital, Wollongong, 2522, Australia
| | - Michael Bussmann
- Institute of Radiation Physics, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, 01328, Germany
| | - Aswin L Hoffmann
- OncoRay - National Center for Radiation Research in Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, 01307, Germany.,Institute of Radiooncology - OncoRay, Helmholtz-Zentrum Dresden - Rossendorf, Dresden, 01328, Germany.,Department of Radiotherapy and Radiation Oncology, Faculty of Medicine and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, 01307, Germany
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Eekers DB, Pijnappel EN, Schijns OE, Colon A, Hoeben A, Zindler JD, Postma AA, Hoffmann AL, Lambin P, Troost EG. Evidence on the efficacy of primary radiosurgery or stereotactic radiotherapy for drug-resistant non-neoplastic focal epilepsy in adults: A systematic review. Seizure 2018; 55:83-92. [DOI: 10.1016/j.seizure.2018.01.009] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Revised: 01/09/2018] [Accepted: 01/11/2018] [Indexed: 12/28/2022] Open
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Vanneste BGL, van Wijk Y, Lutgens LC, Van Limbergen EJ, van Lin EN, van de Beek K, Lambin P, Hoffmann AL. Dynamics of rectal balloon implant shrinkage in prostate VMAT : Influence on anorectal dose and late rectal complication risk. Strahlenther Onkol 2017; 194:31-40. [PMID: 29038832 PMCID: PMC5752748 DOI: 10.1007/s00066-017-1222-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 09/19/2017] [Indexed: 01/20/2023]
Abstract
PURPOSE To assess the effect of a shrinking rectal balloon implant (RBI) on the anorectal dose and complication risk during the course of moderately hypofractionated prostate radiotherapy. METHODS In 15 patients with localized prostate cancer, an RBI was implanted. A weekly kilovolt cone-beam computed tomography (CBCT) scan was acquired to measure the dynamics of RBI volume and prostate-rectum separation. The absolute anorectal volume encompassed by the 2 Gy equieffective 75 Gy isodose (V75Gy) was recalculated as well as the mean anorectal dose. The increase in estimated risk of grade 2-3 late rectal bleeding (LRB) between the start and end of treatment was predicted using nomograms. The observed acute and late toxicities were evaluated. RESULTS A significant shrinkage of RBI volumes was observed, with an average volume of 70.4% of baseline at the end of the treatment. Although the prostate-rectum separation significantly decreased over time, it remained at least 1 cm. No significant increase in V75Gy of the anorectum was observed, except in one patient whose RBI had completely deflated in the third week of treatment. No correlation between mean anorectal dose and balloon deflation was found. The increase in predicted LRB risk was not significant, except in the one patient whose RBI completely deflated. The observed toxicities confirmed these findings. CONCLUSIONS Despite significant decrease in RBI volume the high-dose rectal volume and the predicted LRB risk were unaffected due to a persistent spacing between the prostate and the anterior rectal wall.
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Affiliation(s)
- Ben G L Vanneste
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, P.O. Box 3035, 6202 NA, Maastricht, The Netherlands.
| | - Y van Wijk
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, P.O. Box 3035, 6202 NA, Maastricht, The Netherlands
| | - L C Lutgens
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, P.O. Box 3035, 6202 NA, Maastricht, The Netherlands
| | - E J Van Limbergen
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, P.O. Box 3035, 6202 NA, Maastricht, The Netherlands
| | - E N van Lin
- Radiotherapy Bonn-Rhein-Sieg, Troisdorf, Germany
| | - K van de Beek
- Department of Urology, Maastricht University Medical Center+, Maastricht, The Netherlands
| | - P Lambin
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, P.O. Box 3035, 6202 NA, Maastricht, The Netherlands
| | - A L Hoffmann
- Department of Radiation Oncology (MAASTRO), GROW - School for Oncology and Developmental Biology, Maastricht University Medical Center+, P.O. Box 3035, 6202 NA, Maastricht, The Netherlands
- Institute of Radiooncology - OncoRay, Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany
- Department of Radiotherapy, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Dresden, Germany
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Dankers F, Wijsman R, Troost EGC, Monshouwer R, Bussink J, Hoffmann AL. Esophageal wall dose-surface maps do not improve the predictive performance of a multivariable NTCP model for acute esophageal toxicity in advanced stage NSCLC patients treated with intensity-modulated (chemo-)radiotherapy. Phys Med Biol 2017; 62:3668-3681. [DOI: 10.1088/1361-6560/aa5e9e] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Wijsman R, Dankers F, Troost EG, Hoffmann AL, van der Heijden EH, de Geus-Oei LF, Bussink J. Comparison of toxicity and outcome in advanced stage non-small cell lung cancer patients treated with intensity-modulated (chemo-)radiotherapy using IMRT or VMAT. Radiother Oncol 2017; 122:295-299. [DOI: 10.1016/j.radonc.2016.11.015] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2016] [Revised: 08/23/2016] [Accepted: 11/13/2016] [Indexed: 12/25/2022]
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Schellhammer SM, Hoffmann AL. Prediction and compensation of magnetic beam deflection in MR-integrated proton therapy: a method optimized regarding accuracy, versatility and speed. Phys Med Biol 2017; 62:1548-1564. [DOI: 10.1088/1361-6560/62/4/1548] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Peerlings J, Troost EGC, Nelemans PJ, Cobben DCP, de Boer JCJ, Hoffmann AL, Beets-Tan RGH. The Diagnostic Value of MR Imaging in Determining the Lymph Node Status of Patients with Non-Small Cell Lung Cancer: A Meta-Analysis. Radiology 2016; 281:86-98. [PMID: 27110732 DOI: 10.1148/radiol.2016151631] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Purpose To summarize existing evidence of thoracic magnetic resonance (MR) imaging in determining the nodal status of non-small cell lung cancer (NSCLC) with the aim of elucidating its diagnostic value on a per-patient basis (eg, in treatment decision making) and a per-node basis (eg, in target volume delineation for radiation therapy), with results of cytologic and/or histologic examination as the reference standard. Materials and Methods A systematic literature search for original diagnostic studies was performed in PubMed, Web of Science, Embase, and MEDLINE. The methodologic quality of each study was evaluated by using the Quality Assessment of Diagnostic Accuracy Studies 2, or QUADAS-2, tool. Hierarchic summary receiver operating characteristic curves were generated to estimate the diagnostic performance of MR imaging. Subgroup analyses, expressed as relative diagnostic odds ratios (DORs) (rDORs), were performed to evaluate whether publication year, methodologic quality, and/or method of evaluation (qualitative [ie, lesion size and/or morphology] vs quantitative [eg, apparent diffusion coefficients in diffusion-weighted images]) affected diagnostic performance. Results Twelve of 2551 initially identified studies were included in this meta-analysis (1122 patients; 4302 lymph nodes). On a per-patient basis, the pooled estimates of MR imaging for sensitivity, specificity, and DOR were 0.87 (95% confidence interval [CI]: 0.78, 0.92), 0.88 (95% CI: 0.77, 0.94), and 48.1 (95% CI: 23.4, 98.9), respectively. On a per-node basis, the respective measures were 0.88 (95% CI: 0.78, 0.94), 0.95 (95% CI: 0.87, 0.98), and 129.5 (95% CI: 49.3, 340.0). Subgroup analyses suggested greater diagnostic performance of quantitative evaluation on both a per-patient and per-node basis (rDOR = 2.76 [95% CI: 0.83, 9.10], P = .09 and rDOR = 7.25 [95% CI: 1.75, 30.09], P = .01, respectively). Conclusion This meta-analysis demonstrated high diagnostic performance of MR imaging in staging hilar and mediastinal lymph nodes in NSCLC on both a per-patient and per-node basis. (©) RSNA, 2016 Online supplemental material is available for this article.
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Affiliation(s)
- Jurgen Peerlings
- From the Department of Radiation Oncology (MAASTRO Clinic), GROW School for Oncology and Developmental Biology (J.P., E.G.C.T., A.L.H.), Department of Radiology (J.P., R.G.H.B.), and Department of Epidemiology (P.J.N.), Maastricht University Medical Centre, Dr. Tanslaan 12, 6229 ET Maastricht, the Netherlands; Department of Radiation Oncology, University Medical Centre, Utrecht, the Netherlands (D.C.P.C., J.C.J.d.B.); and Department of Radiation Oncology, Dr Bernard Verbeeten Institute, Tilburg, the Netherlands (D.C.P.C.)
| | - Esther G C Troost
- From the Department of Radiation Oncology (MAASTRO Clinic), GROW School for Oncology and Developmental Biology (J.P., E.G.C.T., A.L.H.), Department of Radiology (J.P., R.G.H.B.), and Department of Epidemiology (P.J.N.), Maastricht University Medical Centre, Dr. Tanslaan 12, 6229 ET Maastricht, the Netherlands; Department of Radiation Oncology, University Medical Centre, Utrecht, the Netherlands (D.C.P.C., J.C.J.d.B.); and Department of Radiation Oncology, Dr Bernard Verbeeten Institute, Tilburg, the Netherlands (D.C.P.C.)
| | - Patricia J Nelemans
- From the Department of Radiation Oncology (MAASTRO Clinic), GROW School for Oncology and Developmental Biology (J.P., E.G.C.T., A.L.H.), Department of Radiology (J.P., R.G.H.B.), and Department of Epidemiology (P.J.N.), Maastricht University Medical Centre, Dr. Tanslaan 12, 6229 ET Maastricht, the Netherlands; Department of Radiation Oncology, University Medical Centre, Utrecht, the Netherlands (D.C.P.C., J.C.J.d.B.); and Department of Radiation Oncology, Dr Bernard Verbeeten Institute, Tilburg, the Netherlands (D.C.P.C.)
| | - David C P Cobben
- From the Department of Radiation Oncology (MAASTRO Clinic), GROW School for Oncology and Developmental Biology (J.P., E.G.C.T., A.L.H.), Department of Radiology (J.P., R.G.H.B.), and Department of Epidemiology (P.J.N.), Maastricht University Medical Centre, Dr. Tanslaan 12, 6229 ET Maastricht, the Netherlands; Department of Radiation Oncology, University Medical Centre, Utrecht, the Netherlands (D.C.P.C., J.C.J.d.B.); and Department of Radiation Oncology, Dr Bernard Verbeeten Institute, Tilburg, the Netherlands (D.C.P.C.)
| | - Johannes C J de Boer
- From the Department of Radiation Oncology (MAASTRO Clinic), GROW School for Oncology and Developmental Biology (J.P., E.G.C.T., A.L.H.), Department of Radiology (J.P., R.G.H.B.), and Department of Epidemiology (P.J.N.), Maastricht University Medical Centre, Dr. Tanslaan 12, 6229 ET Maastricht, the Netherlands; Department of Radiation Oncology, University Medical Centre, Utrecht, the Netherlands (D.C.P.C., J.C.J.d.B.); and Department of Radiation Oncology, Dr Bernard Verbeeten Institute, Tilburg, the Netherlands (D.C.P.C.)
| | - Aswin L Hoffmann
- From the Department of Radiation Oncology (MAASTRO Clinic), GROW School for Oncology and Developmental Biology (J.P., E.G.C.T., A.L.H.), Department of Radiology (J.P., R.G.H.B.), and Department of Epidemiology (P.J.N.), Maastricht University Medical Centre, Dr. Tanslaan 12, 6229 ET Maastricht, the Netherlands; Department of Radiation Oncology, University Medical Centre, Utrecht, the Netherlands (D.C.P.C., J.C.J.d.B.); and Department of Radiation Oncology, Dr Bernard Verbeeten Institute, Tilburg, the Netherlands (D.C.P.C.)
| | - Regina G H Beets-Tan
- From the Department of Radiation Oncology (MAASTRO Clinic), GROW School for Oncology and Developmental Biology (J.P., E.G.C.T., A.L.H.), Department of Radiology (J.P., R.G.H.B.), and Department of Epidemiology (P.J.N.), Maastricht University Medical Centre, Dr. Tanslaan 12, 6229 ET Maastricht, the Netherlands; Department of Radiation Oncology, University Medical Centre, Utrecht, the Netherlands (D.C.P.C., J.C.J.d.B.); and Department of Radiation Oncology, Dr Bernard Verbeeten Institute, Tilburg, the Netherlands (D.C.P.C.)
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Compter I, Peerlings J, Eekers DBP, Postma AA, Ivanov D, Wiggins CJ, Kubben P, Küsters B, Wesseling P, Ackermans L, Schijns OEMG, Lambin P, Hoffmann AL. Technical feasibility of integrating 7 T anatomical MRI in image-guided radiotherapy of glioblastoma: a preparatory study. Magn Reson Mater Phy 2016; 29:591-603. [DOI: 10.1007/s10334-016-0534-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2015] [Revised: 02/03/2016] [Accepted: 02/10/2016] [Indexed: 10/22/2022]
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Pilz K, Hoffmann AL, Baumann M, Troost EG. Vertebral fractures – An underestimated side-effect in patients treated with radio(chemo)therapy. Radiother Oncol 2016; 118:421-3. [DOI: 10.1016/j.radonc.2016.02.021] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2016] [Accepted: 02/18/2016] [Indexed: 11/25/2022]
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Cobben DCP, de Boer HCJ, Tijssen RH, Rutten EGGM, van Vulpen M, Peerlings J, Troost EGC, Hoffmann AL, van Lier ALHMW. Emerging Role of MRI for Radiation Treatment Planning in Lung Cancer. Technol Cancer Res Treat 2015; 15:NP47-NP60. [PMID: 26589726 DOI: 10.1177/1533034615615249] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2015] [Accepted: 10/01/2015] [Indexed: 12/25/2022] Open
Abstract
Magnetic resonance imaging (MRI) provides excellent soft-tissue contrast and allows for specific scanning sequences to optimize differentiation between various tissue types and properties. Moreover, it offers the potential for real-time motion imaging. This makes magnetic resonance imaging an ideal candidate imaging modality for radiation treatment planning in lung cancer. Although the number of clinical research protocols for the application of magnetic resonance imaging for lung cancer treatment is increasing (www.clinicaltrials.gov) and the magnetic resonance imaging sequences are becoming faster, there are still some technical challenges. This review describes the opportunities and challenges of magnetic resonance imaging for radiation treatment planning in lung cancer.
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Affiliation(s)
- David C P Cobben
- Department of Radiation Oncology, University Medical Center, Utrecht, the Netherlands
| | - Hans C J de Boer
- Department of Radiation Oncology, University Medical Center, Utrecht, the Netherlands
| | - Rob H Tijssen
- Department of Radiation Oncology, University Medical Center, Utrecht, the Netherlands
| | - Emma G G M Rutten
- Department of Radiation Oncology, University Medical Center, Utrecht, the Netherlands
| | - Marco van Vulpen
- Department of Radiation Oncology, University Medical Center, Utrecht, the Netherlands
| | - Jurgen Peerlings
- Department of Radiation Oncology, MAASTRO Clinic, GROW-School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands
| | - Esther G C Troost
- Department of Radiation Oncology, MAASTRO Clinic, GROW-School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands.,Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,OncoRay, National Center for Radiation Research in Oncology, Dresden, Germany.,Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Aswin L Hoffmann
- Department of Radiation Oncology, MAASTRO Clinic, GROW-School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands.,Helmholtz-Zentrum Dresden-Rossendorf, Dresden, Germany.,OncoRay, National Center for Radiation Research in Oncology, Dresden, Germany.,Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
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Zindler JD, Thomas CR, Hahn SM, Hoffmann AL, Troost EGC, Lambin P. Increasing the Therapeutic Ratio of Stereotactic Ablative Radiotherapy by Individualized Isotoxic Dose Prescription. J Natl Cancer Inst 2015; 108:djv305. [PMID: 26476075 DOI: 10.1093/jnci/djv305] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2014] [Accepted: 09/25/2015] [Indexed: 12/25/2022] Open
Abstract
To obtain a favorable tradeoff between treatment benefits and morbidity ("therapeutic ratio"), radiotherapy (RT) dose is prescribed according to the tumor volume, with the goal of controlling the disease while respecting normal tissue tolerance levels. We propose a new paradigm for tumor dose prescription in stereotactic ablative radiotherapy (SABR) based on organ-at-risk (OAR) tolerance levels called isotoxic dose prescription (IDP), which is derived from experiences and limitations of conventionally fractionated radiotherapy. With IDP, the radiation dose is prescribed based on the predefined level of normal tissue complication probability of a nearby dose-limiting OAR at a prespecified dose-volume constraint. Simultaneously, the prescribed total tumor dose (TTD) is maximized to the technically highest achievable level in order to increase the local tumor control probability (TCP). IDP is especially relevant for tumors located at eloquent locations or for large tumors in which severe toxicity has been described. IDP will result in a lower RT dose or a treatment scheduled with more fractions if the OAR tolerance level is exceeded, and potential dose escalation occurs when the OAR tolerance level allows it and when it is expected to be beneficial (if TCP < 90%). For patients with small tumors at noneloquent sites, the current SABR dose prescription already results in high rates of local control at low toxicity rates. In this review, the concept of IDP is described in the context of SABR.
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Affiliation(s)
- Jaap D Zindler
- Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands (JDZ, ALH, EGCT, PL); Department of Radiation Medicine, Knight Cancer Institute, Oregon Health & Science University, Oregon, OR (CRTJr); Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (SMH); Helmholtz Zentrum Dresden-Rossendorf, Dresden, Germany (ALH, EGCT); Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany (ALH, EGCT).
| | - Charles R Thomas
- Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands (JDZ, ALH, EGCT, PL); Department of Radiation Medicine, Knight Cancer Institute, Oregon Health & Science University, Oregon, OR (CRTJr); Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (SMH); Helmholtz Zentrum Dresden-Rossendorf, Dresden, Germany (ALH, EGCT); Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany (ALH, EGCT)
| | - Stephen M Hahn
- Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands (JDZ, ALH, EGCT, PL); Department of Radiation Medicine, Knight Cancer Institute, Oregon Health & Science University, Oregon, OR (CRTJr); Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (SMH); Helmholtz Zentrum Dresden-Rossendorf, Dresden, Germany (ALH, EGCT); Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany (ALH, EGCT)
| | - Aswin L Hoffmann
- Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands (JDZ, ALH, EGCT, PL); Department of Radiation Medicine, Knight Cancer Institute, Oregon Health & Science University, Oregon, OR (CRTJr); Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (SMH); Helmholtz Zentrum Dresden-Rossendorf, Dresden, Germany (ALH, EGCT); Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany (ALH, EGCT)
| | - Esther G C Troost
- Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands (JDZ, ALH, EGCT, PL); Department of Radiation Medicine, Knight Cancer Institute, Oregon Health & Science University, Oregon, OR (CRTJr); Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (SMH); Helmholtz Zentrum Dresden-Rossendorf, Dresden, Germany (ALH, EGCT); Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany (ALH, EGCT)
| | - Philippe Lambin
- Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Maastricht, the Netherlands (JDZ, ALH, EGCT, PL); Department of Radiation Medicine, Knight Cancer Institute, Oregon Health & Science University, Oregon, OR (CRTJr); Division of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX (SMH); Helmholtz Zentrum Dresden-Rossendorf, Dresden, Germany (ALH, EGCT); Department of Radiation Oncology, Medical Faculty and University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany (ALH, EGCT)
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Wijsman R, Dankers F, Troost EGC, Hoffmann AL, van der Heijden EHFM, de Geus-Oei LF, Bussink J. Multivariable normal-tissue complication modeling of acute esophageal toxicity in advanced stage non-small cell lung cancer patients treated with intensity-modulated (chemo-)radiotherapy. Radiother Oncol 2015; 117:49-54. [PMID: 26341608 DOI: 10.1016/j.radonc.2015.08.010] [Citation(s) in RCA: 48] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2015] [Revised: 08/10/2015] [Accepted: 08/11/2015] [Indexed: 12/25/2022]
Abstract
BACKGROUND AND PURPOSE The majority of normal-tissue complication probability (NTCP) models for acute esophageal toxicity (AET) in advanced stage non-small cell lung cancer (AS-NSCLC) patients treated with (chemo-)radiotherapy are based on three-dimensional conformal radiotherapy (3D-CRT). Due to distinct dosimetric characteristics of intensity-modulated radiation therapy (IMRT), 3D-CRT based models need revision. We established a multivariable NTCP model for AET in 149 AS-NSCLC patients undergoing IMRT. MATERIALS AND METHODS An established model selection procedure was used to develop an NTCP model for Grade ⩾2 AET (53 patients) including clinical and esophageal dose-volume histogram parameters. RESULTS The NTCP model predicted an increased risk of Grade ⩾2 AET in case of: concurrent chemoradiotherapy (CCR) [adjusted odds ratio (OR) 14.08, 95% confidence interval (CI) 4.70-42.19; p<0.001], increasing mean esophageal dose [Dmean; OR 1.12 per Gy increase, 95% CI 1.06-1.19; p<0.001], female patients (OR 3.33, 95% CI 1.36-8.17; p=0.008), and ⩾cT3 (OR 2.7, 95% CI 1.12-6.50; p=0.026). The AUC was 0.82 and the model showed good calibration. CONCLUSIONS A multivariable NTCP model including CCR, Dmean, clinical tumor stage and gender predicts Grade ⩾2 AET after IMRT for AS-NSCLC. Prior to clinical introduction, the model needs validation in an independent patient cohort.
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Affiliation(s)
- Robin Wijsman
- Department of Radiation Oncology, Radboud University Medical Center, Nijmegen, The Netherlands.
| | - Frank Dankers
- Department of Radiation Oncology, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Esther G C Troost
- Institute of Radiooncology, Helmholtz-Zentrum Dresden-Rossendorf, Germany; Department of Radiotherapy and Radiooncology, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Germany; OncoRay, National Center for Radiation Research in Oncology, Dresden, Germany
| | - Aswin L Hoffmann
- Institute of Radiooncology, Helmholtz-Zentrum Dresden-Rossendorf, Germany; Department of Radiotherapy and Radiooncology, University Hospital Carl Gustav Carus at the Technische Universität Dresden, Germany
| | | | - Lioe-Fee de Geus-Oei
- Department of Radiology, Leiden University Medical Center, The Netherlands; Biomedical Photonic Imaging Group, MIRA Institute, University of Twente, Enschede, The Netherlands
| | - Johan Bussink
- Department of Radiation Oncology, Radboud University Medical Center, Nijmegen, The Netherlands
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Balvert M, van Hoof SJ, Granton PV, Trani D, den Hertog D, Hoffmann AL, Verhaegen F. A framework for inverse planning of beam-on times for 3D small animal radiotherapy using interactive multi-objective optimisation. Phys Med Biol 2015; 60:5681-98. [DOI: 10.1088/0031-9155/60/14/5681] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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Balvert M, Gorissen BL, den Hertog D, Hoffmann AL. Dwell time modulation restrictions do not necessarily improve treatment plan quality for prostate HDR brachytherapy. Phys Med Biol 2014; 60:537-48. [DOI: 10.1088/0031-9155/60/2/537] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Gorissen BL, Hoffmann AL. Comment on 'comparative evaluation of two dose optimization methods for image-guided, highly-conformal, tandem and ovoids cervix brachytherapy planning'. Phys Med Biol 2014; 59:245-6. [PMID: 24334524 DOI: 10.1088/0031-9155/59/1/245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Bram L Gorissen
- Department of Econometrics and Operations Research/Center for Economic Research (CentER), Tilburg University, PO Box 90153, 5000 LE Tilburg, The Netherlands
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Hoffmann AL, Nahum AE. Fractionation in normal tissues: the (α/β)effconcept can account for dose heterogeneity and volume effects. Phys Med Biol 2013; 58:6897-914. [DOI: 10.1088/0031-9155/58/19/6897] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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van Gestel KMJ, Buurman DJM, Pijls R, Kessler PAWH, van den Ende PLA, Hoffmann AL, Troost EGC. Locally advanced verrucous carcinoma of the oral cavity: treatment using customized mold HDR brachytherapy instead of hemi-maxillectomy. Strahlenther Onkol 2013; 189:894-8. [PMID: 23963206 DOI: 10.1007/s00066-013-0412-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2013] [Accepted: 06/17/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND Oral verrucous carcinomas are locally invasive but rarely metastasize. Current treatment options include surgery and external beam radiotherapy (EBRT). In medical inoperable patients or irresectable tumors, high-dose-rate (HDR) brachytherapy is a valid alternative. CASE We present an 85-year-old man with functionally irresectable cT3N0M0 verrucous carcinoma superficially spreading along the upper alveolar ridge to the retro-alveolar triangle, with infiltration of the left soft and hard palate and buccal mucosa. Using a customized intraoral mold, this patient was treated with HDR brachytherapy delivering a dose of 48 Gy in 12 fractions three times per week. Treatment was well tolerated, and after prolonged confluent mucositis the tumor is in complete remission. REVIEW OF LITERATURE AND CONCLUSION The scarce literature on customized mold HDR brachytherapy in maxillary tumors is reviewed and recommendations for other head and neck tumors are given.
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Affiliation(s)
- K M J van Gestel
- Department of Radiation Oncology (MAASTRO), GROW School for Oncology and Developmental Biology, Maastricht University Medical Centre, Dr Tanslaan 12, 6229 ET, Maastricht, The Netherlands
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Troost EGC, Hoffmann AL, Bussink J. Balancing radiation pneumonitis versus locoregional tumor control in non-small-cell lung cancer. J Thorac Oncol 2013; 8:e47. [PMID: 23710518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
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Troost EG, Hoffmann AL, Bussink J. Balancing Radiation Pneumonitis Versus Locoregional Tumor Control in Non–Small-Cell Lung Cancer. J Thorac Oncol 2013. [DOI: 10.1016/s1556-0864(15)32833-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Hoffmann AL, Huizenga H, Kaanders JHAM. Employing the therapeutic operating characteristic (TOC) graph for individualised dose prescription. Radiat Oncol 2013; 8:55. [PMID: 23497640 PMCID: PMC3606307 DOI: 10.1186/1748-717x-8-55] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 02/28/2013] [Indexed: 11/25/2022] Open
Abstract
Background In current practice, patients scheduled for radiotherapy are treated according to ‘rigid’ protocols with predefined dose prescriptions that do not consider risk-taking preferences of individuals. The therapeutic operating characteristic (TOC) graph is applied as a decision-aid to assess the trade-off between treatment benefit and morbidity to facilitate dose prescription customisation. Methods Historical dose-response data from prostate cancer patient cohorts treated with 3D-conformal radiotherapy is used to construct TOC graphs. Next, intensity-modulated (IMRT) plans are generated by optimisation based on dosimetric criteria and dose-response relationships. TOC graphs are constructed for dose-scaling of the optimised IMRT plan and individualised dose prescription. The area under the TOC curve (AUC) is estimated to measure the therapeutic power of these plans. Results On a continuous scale, the TOC graph directly visualises treatment benefit and morbidity risk of physicians’ or patients’ choices for dose (de-)escalation. The trade-off between these probabilities facilitates the selection of an individualised dose prescription. TOC graphs show broader therapeutic window and higher AUCs with increasing target dose heterogeneity. Conclusions The TOC graph gives patients and physicians access to a decision-aid and read-out of the trade-off between treatment benefit and morbidity risks for individualised dose prescription customisation over a continuous range of dose levels.
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Affiliation(s)
- Aswin L Hoffmann
- Department of Radiation Oncology, Radboud University Nijmegen Medical Center, Nijmegen, 6500 HB, The Netherlands.
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Gorissen BL, den Hertog D, Hoffmann AL. Mixed integer programming improves comprehensibility and plan quality in inverse optimization of prostate HDR brachytherapy. Phys Med Biol 2013; 58:1041-57. [DOI: 10.1088/0031-9155/58/4/1041] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Idema AJ, Hoffmann AL, Boogaarts HD, Troost EG, Wesseling P, Heerschap A, van der Graaf WT, Grotenhuis JA, Oyen WJ. 3′-Deoxy-3′-18F-Fluorothymidine PET–Derived Proliferative Volume Predicts Overall Survival in High-Grade Glioma Patients. J Nucl Med 2012; 53:1904-10. [DOI: 10.2967/jnumed.112.105544] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
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Strik HM, Buhk JH, Wrede A, Hoffmann AL, Bock HC, Christmann M, Kaina B. Rechallenge with temozolomide with different scheduling is effective in recurrent malignant gliomas. Mol Med Rep 2012; 1:863-7. [PMID: 21479498 DOI: 10.3892/mmr_00000042] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Treatment of recurrent malignant glioma, which has a poor patient prognosis, has not been standardised. Moreover, it is unclear whether repeated treatment with temozolomide is effective in patients who received previous temozolomide treatment before developing a recurrence. Here, we present the results of a high-dose individually adapted 21-day regimen demonstrating that rechallenge is effective even in patients expressing O6-methylguanine-DNA methyltransferase (MGMT) in the tumor. Twenty-one patients with recurrent malignant gliomas pre-treated with temozolomide, 18 WHO IV glioblastoma (GBM) and 3 WHO III patients, received 100 mg/m2 temozolomide on days 1-21/28. The GBM patients had a median Karnofsky performance status of 60% and a median age of 54.8 years. Blood counts decreased continuously, enabling a gradual dose adaptation. When blood counts dropped below normal values, temozolomide was applied on days 1-5/7. Dosage was reduced to 50-75 mg/m2 in 11 patients and gradually increased up to 130 mg/m2 in 3 patients. WHO grade 3/4 toxicity was hematological in 3 patients and non-hematological in 3 patients. In GBM patients (n=18), response after >3 months was complete in 3 patients, partial in 1 (22%), stable disease in 7 (39%) and progressive disease in 7 (39%). Progression-free survival at 6 months (PFS-6M) was 39%. Median survival was 9.1 months from relapse and 17.9 months overall. Of the patients with unmethylated MGMT promoter, 2/7 were progression-free for >6 (15 and 19) months. The data indicate that rechallenge with near-continuous, higher-dose temozolomide (100 mg/m2 on days 1-21/28 or days 1-5/7 with individual dose adaptation) is also feasible in patients with critical blood counts. Objective responses can be achieved even after relapse during a conventional 5/28-day regimen. The resistance of tumors characterized by unmethylated MGMT promoter may be overcome by near continuous temozolomide administration, which is probably most effective with a 5/7-day schedule. In spite of the relatively poor clinical prognosis, the data indicate that rechallenge with temozolomide with a dose-dense and long-lasting administration protocol is tolerable and comparable with other reported treatment protocols involving temozolomide.
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Affiliation(s)
- H M Strik
- Department of Neurology, University of Göttingen, D-37099 Göttingen, Germany.
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Hoffmann AL, Troost EGC, Huizenga H, Kaanders JHAM, Bussink J. Individualized dose prescription for hypofractionation in advanced non-small-cell lung cancer radiotherapy: an in silico trial. Int J Radiat Oncol Biol Phys 2012; 83:1596-602. [PMID: 22245206 DOI: 10.1016/j.ijrobp.2011.10.032] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2011] [Revised: 10/14/2011] [Accepted: 10/17/2011] [Indexed: 12/25/2022]
Abstract
PURPOSE Local tumor control and outcome remain poor in patients with advanced non-small-cell lung cancer (NSCLC) treated by external beam radiotherapy. We investigated the therapeutic gain of individualized dose prescription with dose escalation based on normal tissue dose constraints for various hypofractionation schemes delivered with intensity-modulated radiation therapy. METHODS AND MATERIALS For 38 Stage III NSCLC patients, the dose level of an existing curative treatment plan with standard fractionation (66 Gy) was rescaled based on dose constraints for the lung, spinal cord, esophagus, brachial plexus, and heart. The effect on tumor total dose (TTD) and biologic tumor effective dose in 2-Gy fractions (TED) corrected for overall treatment time (OTT) was compared for isotoxic and maximally tolerable schemes given in 15, 20, and 33 fractions. Rescaling was accomplished by altering the dose per fraction and/or the number of fractions while keeping the relative dose distribution of the original treatment plan. RESULTS For 30 of the 38 patients, dose escalation by individualized hypofractionation yielded therapeutic gain. For the maximally tolerable dose scheme in 33 fractions (MTD(33)), individualized dose escalation resulted in a 2.5-21% gain in TTD. In the isotoxic schemes, the number of fractions could be reduced with a marginal increase in TED. For the maximally tolerable dose schemes, the TED could be escalated up to 36.6%, and for all patients beyond the level of the isotoxic and the MTD(33) schemes (range, 3.3-36.6%). Reduction of the OTT contributed to the therapeutic gain of the shortened schemes. For the maximally tolerable schemes, the maximum esophageal dose was the dominant dose-limiting constraint in most patients. CONCLUSIONS This modeling study showed that individualized dose prescription for hypofractionation in NSCLC radiotherapy, based on scaling of existing treatment plans up to normal tissue dose constraints, enables dose escalation with therapeutic gain in 79% of the cases.
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Affiliation(s)
- Aswin L Hoffmann
- Radboud University Nijmegen Medical Centre, Department of Radiation Oncology, Nijmegen, The Netherlands
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Chrispijn M, Nevens F, Gevers TJG, Vanslembrouck R, van Oijen MGH, Coudyzer W, Hoffmann AL, Dekker HM, de Man RA, van Keimpema L, Drenth JPH. The long-term outcome of patients with polycystic liver disease treated with lanreotide. Aliment Pharmacol Ther 2012; 35:266-74. [PMID: 22111942 DOI: 10.1111/j.1365-2036.2011.04923.x] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND Polycystic liver disease (PLD) is a phenotypical expression of autosomal dominant polycystic kidney disease and isolated polycystic liver disease. Somatostatin analogues, such as lanreotide, reduce polycystic liver volume. AIM To establish long-term outcome and safety of lanreotide. METHODS This was an open-label, observational extension study of a 6-month, randomised, placebo-controlled trial with lanreotide (120 mg/month) in PLD. The length of total treatment was 12 months. Primary endpoint was relative change in liver volume, as determined by CT-volumetry after 12 months of treatment. We offered patients a CT scan 6 months after stopping lanreotide. RESULTS A total of 41/54 (76%) patients participated in the extension study. Liver volume decreased by 4% (IQR -8% to -1%) after 12 months of treatment. The greatest effect was observed during the first 6 months of treatment (decrease of 4% (IQR -6% to -1%)). Liver volume remained unchanged during the following 6 months. We found that liver volume increased by 4% (IQR 0-6%) 6 months after end of treatment (n = 22). CONCLUSIONS Lanreotide reduces liver volume within the first 6 months of treatment and the beneficial effect is maintained in the following 6 months. Stopping results in recurrence of polycystic liver growth. This suggests that continuous use of lanreotide is needed to maintain its effect.
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Affiliation(s)
- M Chrispijn
- Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Centre, The Netherlands
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Smeenk RJ, Hoffmann AL, Hopman WPM, van Lin ENJT, Kaanders JHAM. Dose-effect relationships for individual pelvic floor muscles and anorectal complaints after prostate radiotherapy. Int J Radiat Oncol Biol Phys 2011; 83:636-44. [PMID: 22137024 DOI: 10.1016/j.ijrobp.2011.08.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 06/28/2011] [Accepted: 08/08/2011] [Indexed: 10/14/2022]
Abstract
PURPOSE To delineate the individual pelvic floor muscles considered to be involved in anorectal toxicity and to investigate dose-effect relationships for fecal incontinence-related complaints after prostate radiotherapy (RT). METHODS AND MATERIALS In 48 patients treated for localized prostate cancer, the internal anal sphincter (IAS) muscle, the external anal sphincter (EAS) muscle, the puborectalis muscle (PRM), and the levator ani muscles (LAM) in addition to the anal wall (Awall) and rectal wall (Rwall) were retrospectively delineated on planning computed tomography scans. Dose parameters were obtained and compared between patients with and without fecal urgency, incontinence, and frequency. Dose-effect curves were constructed. Finally, the effect of an endorectal balloon, which was applied in 28 patients, was investigated. RESULTS The total volume of the pelvic floor muscles together was about three times that of the Awall. The PRM was exposed to the highest RT dose, whereas the EAS received the lowest dose. Several anal and rectal dose parameters, as well as doses to all separate pelvic floor muscles, were associated with urgency, while incontinence was associated mainly with doses to the EAS and PRM. Based on the dose-effect curves, the following constraints regarding mean doses could be deduced to reduce the risk of urgency: ≤ 30 Gy to the IAS; ≤ 10 Gy to the EAS; ≤ 50 Gy to the PRM; and ≤ 40 Gy to the LAM. No dose-effect relationships for frequency were observed. Patients treated with an endorectal balloon reported significantly less urgency and incontinence, while their treatment plans showed significantly lower doses to the Awall, Rwall, and all pelvic floor muscles. CONCLUSIONS Incontinence-related complaints show specific dose-effect relationships to individual pelvic floor muscles. Dose constraints for each muscle can be identified for RT planning. When only the Awall is delineated, substantial components of the continence apparatus are excluded.
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Affiliation(s)
- Robert Jan Smeenk
- Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Monshouwer R, Hoffmann AL, Kunze-Busch M, Bussink J, Kaanders JHAM, Huizenga H. A practical approach to assess clinical planning tradeoffs in the design of individualized IMRT treatment plans. Radiother Oncol 2010; 97:561-6. [PMID: 21074884 DOI: 10.1016/j.radonc.2010.10.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2010] [Revised: 08/18/2010] [Accepted: 10/02/2010] [Indexed: 10/18/2022]
Abstract
BACKGROUND AND PURPOSE To investigate the tradeoffs between organ at risk sparing and tumour coverage for IMRT treatment of lung tumours, and to develop a tool for clinical use to graphically represent these tradeoffs. MATERIAL AND METHODS For 5 patients with inoperable non-small cell lung cancer (NSCLC) different IMRT plans were generated using a standard TPS. The plans were automatically generated for a range of IMRT settings (weights and dose levels of the objective functions) and were systematically evaluated, focusing on the tradeoffs between organ at risk (OAR) dose and target coverage. A method to analyze and visualize planning tradeoffs was developed and evaluated. RESULTS Lung and oesophagus were identified as the critical organs at risk for NSCLC, the sparing of which strongly influences PTV coverage. Systematically analyzing the tradeoffs between these organs revealed that the sparing of these organs was approximately linearly related to PTV coverage parameters. Using this property, a tool was developed to graphically present the tradeoffs between the sparing of these organs at risk and the PTV coverage. The tool is an effective method to visualize the tradeoffs. CONCLUSIONS A tool was developed to assist IMRT plan design and selection. The clear presentation of the tradeoffs between OAR dose and coverage facilitates the optimization process and offers additional information to the clinician for a patient specific choice of the optimal IMRT plan.
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Affiliation(s)
- René Monshouwer
- Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, The Netherlands.
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Smeenk RJ, Hopman WPM, Hoffmann AL, van Lin ENJT, Kaanders JHAM. Differences in radiation dosimetry and anorectal function testing imply that anorectal symptoms may arise from different anatomic substrates. Int J Radiat Oncol Biol Phys 2010; 82:145-52. [PMID: 20950951 DOI: 10.1016/j.ijrobp.2010.08.023] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2009] [Revised: 08/19/2010] [Accepted: 08/19/2010] [Indexed: 11/28/2022]
Abstract
PURPOSE To explore the influence of functional changes and dosimetric parameters on specific incontinence-related anorectal complaints after prostate external beam radiotherapy and to estimate dose-effect relations for the anal wall and rectal wall. METHODS AND MATERIALS Sixty patients, irradiated for localized prostate cancer, underwent anorectal manometry and barostat measurements to evaluate anal pressures, rectal capacity, and rectal sensory functions. In addition, 30 untreated men were analyzed as a control group. In 36 irradiated patients, the anal wall and rectal wall were retrospectively delineated on planning computed tomography scans, and dosimetric parameters were retrieved from the treatment plans. Functional and dosimetric parameters were compared between patients with and without complaints, focusing on urgency, incontinence, and frequency. RESULTS After external beam radiotherapy, reduced anal pressures and tolerated rectal volumes were observed, irrespective of complaints. Patients with urgency and/or incontinence showed significantly lower anal resting pressures (mean 38 and 39 vs. 49 and 50 mm Hg) and lower tolerated rectal pressures (mean 28 and 28 vs. 33 and 34 mm Hg), compared to patients without these complaints. In patients with frequency, almost all rectal parameters were reduced. Several dosimetric parameters to the anal wall and rectal wall were predictive for urgency (e.g., anal D(mean)>38 Gy), whereas some anal wall parameters correlated to incontinence and no dose-effect relation for frequency was found. CONCLUSIONS Anorectal function deteriorates after external beam radiotherapy. Different incontinence-related complaints show specific anorectal dysfunctions, suggesting different anatomic and pathophysiologic substrates: urgency and incontinence seem to originate from both anal wall and rectal wall, whereas frequency seems associated with rectal wall dysfunction. Also, dose-effect relations differed between these complaints. This implies that anal wall and rectal wall should be considered separate organs in radiotherapy planning.
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Affiliation(s)
- Robert Jan Smeenk
- Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Troost EGC, Bussink J, Hoffmann AL, Boerman OC, Oyen WJG, Kaanders JHAM. 18F-FLT PET/CT for early response monitoring and dose escalation in oropharyngeal tumors. J Nucl Med 2010; 51:866-74. [PMID: 20484426 DOI: 10.2967/jnumed.109.069310] [Citation(s) in RCA: 129] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
UNLABELLED Accelerated tumor cell proliferation is an important mechanism adversely affecting therapeutic outcome in head and neck cancer. 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) is a PET tracer to noninvasively image tumor cell proliferation. The aims of this study were to monitor early tumor response based on repetitive (18)F-FLT PET/CT scans and to identify subvolumes with high proliferative activity eligible for dose escalation. METHODS Ten patients with oropharyngeal tumors underwent an (18)F-FLT PET/CT scan before and twice during radiotherapy. The primary tumor and metastatic lymph nodes (gross tumor volume, or GTV) were delineated on CT (GTV(CT)) and after segmentation of the PET signal using the 50% isocontour of the maximum signal intensity or an adaptive threshold based on the signal-to-background ratio (GTV(SBR)). GTVs were calculated, and similarity between GTV(CT) and GTV(SBR) was assessed. Within GTV(SBR), the maximum and mean standardized uptake value (SUV(max) and SUV(mean), respectively) was calculated. Within GTV(CT), tumor subvolumes with high proliferative activity based on the 80% isocontour (GTV(80%)) were identified for radiotherapy planning with dose escalation. RESULTS The GTV(CT) decreased significantly in the fourth week but not in the initial phase of treatment. SUV(max) and SUV(mean) decreased significantly as early as 1 wk after therapy initiation and even further before the fourth week of treatment. For the primary tumor, the average (+/-SD) SUV(mean) of the GTV(SBR) was 4.7 +/- 1.6, 2.0 +/- 0.9, and 1.3 +/- 0.2 for the consecutive scans (P < 0.0001). The similarity between GTV(CT) and GTV(SBR) decreased during treatment, indicating an enlargement of GTV(SBR) outside GTV(CT) caused by the increasing difficulty of segmenting tracer uptake in the tumor from the background and by proliferative activity in the nearby tonsillar tissue. GTV(80%) was successfully identified in all primary tumors and metastatic lymph nodes, and dose escalation based on the GTV(80%) was demonstrated to be technically feasible. CONCLUSION (18)F-FLT is a promising PET tracer for imaging tumor cell proliferation in head and neck carcinomas. Signal changes in (18)F-FLT PET precede volumetric tumor response and are therefore suitable for early response assessment. Definition of tumor subvolumes with high proliferative activity and dose escalation to these regions are technically feasible.
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Affiliation(s)
- Esther G C Troost
- Department of Radiation Oncology, Institute of Oncology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Van Keimpema L, Nevens F, Vanslembrouck R, Van Oijen GH, Hoffmann AL, Dekker HM, De Man RA, Drenth JPH. More on Clinical Renal Genetics. Clin J Am Soc Nephrol 2010. [DOI: 10.2215/01.cjn.0000927100.71587.13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/28/2023]
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Grünfeld JP, Hwu WL, Van Keimpema L, Alamovitch S, Zivna M, Brown EJ, Chien YH, Lee NC, Chiang SC, Dobrovolny R, Huang AC, Yeh HY, Chao MC, Lin SJ, Kitagawa T, Desnick RJ, Hsu LW, Nevens F, Vanslembrouck R, Van Oijen GH, Hoffmann AL, Dekker HM, De Man RA, Drenth JPH, Plaisier E, Favrole P, Prost C, Chen Z, Van Agrmael T, Marro B, Ronco P, Hulkova H, Matignon M, Hodanova K, Vylet'al P, Kalbacova M, Baresova V, Sikora J, Blazkova H, Zivny J, Ivanek R, Stranecky V, Sovova J, Claes K, Lerut E, Fryns JP, Hart PS, Hart TC, Adams JN, Pawtowski A, Clemessy M, Gasc JM, Gubler MC, Antignac C, Elleder M, Kapp K, Grimbert P, Bleyer AJ, Kmoch S, Schlöndorff JS, Becker DJ, Tsukaguchi H, Uschinski AL, Higgs HN, Henderson JM, Pollak MR. More on Clinical Renal GeneticsNewborn screening for Fabry disease in Taiwan reveals a high incidence of the later-onset mutation c.936+919G>A (IVS4+919G>A). Hum Mutat 30: 1397–1405, 2009Lanreotide reduces the volume of polycystic liver: A randomized, double-blind, placebo-controlled trial. Gastroenterology 137: 1661–1668, 2009Cerebrovascular disease related to COL4A1 mutations in HANAC syndrome. Neurology 73: 1873–1882, 2009Dominant renin gene mutations associated with early-onset hyperuricemia, anemia, and chronic renal failure. Am J Hum Genet 85: 204–213, 2009Mutations in the formin gene INF2 cause focal segmental glomerulosclerosis. Nat Genet 42: 72–76, 2009. Clin J Am Soc Nephrol 2010; 5:563-7. [DOI: 10.2215/cjn.01720210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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van Keimpema L, Nevens F, Vanslembrouck R, van Oijen MGH, Hoffmann AL, Dekker HM, de Man RA, Drenth JPH. Lanreotide reduces the volume of polycystic liver: a randomized, double-blind, placebo-controlled trial. Gastroenterology 2009; 137:1661-8.e1-2. [PMID: 19646443 DOI: 10.1053/j.gastro.2009.07.052] [Citation(s) in RCA: 174] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/19/2009] [Revised: 06/22/2009] [Accepted: 07/10/2009] [Indexed: 02/07/2023]
Abstract
BACKGROUND & AIMS Therapy for polycystic liver is invasive, expensive, and has disappointing long-term results. Treatment with somatostatin analogues slowed kidney growth in patients with polycystic kidney disease (PKD) and reduced liver and kidney volume in a PKD rodent model. We evaluated the effects of lanreotide, a somatostatin analogue, in patients with polycystic liver because of autosomal-dominant (AD) PKD or autosomal-dominant polycystic liver disease (PCLD). METHODS We performed a randomized, double-blind, placebo-controlled trial in 2 tertiary referral centers. Patients with polycystic liver (n = 54) were randomly assigned to groups given lanreotide (120 mg) or placebo, administered every 28 days for 24 weeks. The primary end point was the difference in total liver volume, measured by computerized tomography at weeks 0 and 24. Analyses were performed on an intention-to-treat basis. RESULTS Baseline characteristics were comparable for both groups, except that more patients with ADPKD were assigned to the placebo group (P = .03). The mean liver volume decreased 2.9%, from 4606 mL (95% confidence interval (CI): 547-8665) to 4471 mL (95% CI: 542-8401 mL), in patients given lanreotide. In the placebo group, the mean liver volume increased 1.6%, from 4689 mL (95% CI: 613-8765 mL) to 4895 mL (95% CI: 739-9053 mL) (P < .01). Post hoc stratification for patients with ADPKD or PCLD revealed similar changes in liver volume, with statistically significant differences in patients given lanreotide (P < .01 for both diseases). CONCLUSIONS In patients with polycystic liver, 6 months of treatment with lanreotide reduces liver volume.
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Affiliation(s)
- Loes van Keimpema
- Department of Gastroenterology and Hepatology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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Schinagl DAX, Hoffmann AL, Vogel WV, van Dalen JA, Verstappen SMM, Oyen WJG, Kaanders JHAM. Can FDG-PET assist in radiotherapy target volume definition of metastatic lymph nodes in head-and-neck cancer? Radiother Oncol 2009; 91:95-100. [PMID: 19285354 DOI: 10.1016/j.radonc.2009.02.007] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2008] [Revised: 01/21/2009] [Accepted: 02/09/2009] [Indexed: 01/27/2023]
Abstract
BACKGROUND AND PURPOSE The role of FDG-PET in radiotherapy target volume definition of the neck was evaluated by comparing eight methods of FDG-PET segmentation to the current CT-based practice of lymph node assessment in head-and-neck cancer patients. MATERIALS AND METHODS Seventy-eight head-and-neck cancer patients underwent coregistered CT- and FDG-PET scans. Lymph nodes were classified as "enlarged" if the shortest axial diameter on CT was 10mm, and as "marginally enlarged" if it was 7-10mm. Subsequently, lymph nodes were assessed on FDG-PET applying eight segmentation methods: visual interpretation (PET(VIS)), applying fixed thresholds at a standardized uptake value (SUV) of 2.5 and at 40% and 50% of the maximum signal intensity of the primary tumor (PET(SUV), PET(40%), PET(50%)) and applying a variable threshold based on the signal-to-background ratio (PET(SBR)). Finally, PET(40%N), PET(50%N) and PET(SBRN) were acquired using the signal of the lymph node as the threshold reference. RESULTS Of 108 nodes classified as "enlarged" on CT, 75% were also identified by PET(VIS), 59% by PET(40%), 43% by PET(50%) and 43% by PET(SBR). Of 100 nodes classified as "marginally enlarged", only a minority were visualized by FDG-PET. The respective numbers were 26%, 10%, 7% and 8% for PET(VIS), PET(40%), PET(50%) and PET(SBR). PET(40%N), PET(50%N) and PET(SBRN), respectively, identified 66%, 82% and 96% of the PET(VIS)-positive nodes. CONCLUSIONS Many lymph nodes that are enlarged and considered metastatic by standard CT-based criteria appear to be negative on FDG-PET scan. Alternately, a small proportion of marginally enlarged nodes are positive on FDG-PET scan. However, the results are largely dependent on the PET segmentation tool used, and until proper validation FDG-PET is not recommended for target volume definition of metastatic lymph nodes in routine practice.
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Affiliation(s)
- Dominic A X Schinagl
- Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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Hoffmann AL, den Hertog D, Siem AYD, Kaanders JHAM, Huizenga H. Convex reformulation of biologically-based multi-criteria intensity-modulated radiation therapy optimization including fractionation effects. Phys Med Biol 2008; 53:6345-62. [DOI: 10.1088/0031-9155/53/22/006] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Rykova EI, Skvortsova TE, Hoffmann AL, Tamkovich SN, Starikov AV, Bryzgunova OE, Permiakova VI, Warnecke JM, Sczakiel G, Vlasov VV, Laktionov PP. [Breast cancer diagnostics based on extracellular DNA and RNA circulating in blood]. Biomed Khim 2008; 54:94-103. [PMID: 18421914] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Extracellular DNA and RNA were extracted from blood plasma and cell surface-bound fractions of patients with breast tumors and healthy controls. Frequency of RASSF1A, Cyclin D2 and RARbeta2 methylation was detected using methylation-specific PCR in the extracellular DNA, extracted from plasma and cell-surface bound fractions of patient blood. Methylation of at least one of these genes was found in plasma of 13% patients with benign breast fibroadenoma and in 60% of breast cancer patients. Using cell-surface bound DNA as a substrate for PCR have lead to increase of gene methylation detection frequency up to 87% in fibroadenoma and 95% in breast cancer patients without false positive controls. GAPDH, RASSF8, Ki-67 RNA and 18S RNA were quantified using RT-qPCR of the extracellular RNA circulating in blood of patients with breast tumors and healthy controls. The main part of the extracellular RNA was shown to be cell-surface bound. Results show a higher amount of RASSF8, Ki-67 RNA and 18S RNA in plasma and cell-bound fraction of patients with breast cancer compared with patients with benign tumors and healthy controls. The data indicate that the specific RNA quantification in blood plasma is valuable for discrimination between cancer and benign tumors, which can be detected with high sensitivity using analysis of methylated RASSF1A, Cyclin D2 and RARbeta2 genes in extracellular circulating DNA.
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Schinagl DAX, Vogel WV, Hoffmann AL, van Dalen JA, Oyen WJ, Kaanders JHAM. Comparison of five segmentation tools for 18F-fluoro-deoxy-glucose-positron emission tomography-based target volume definition in head and neck cancer. Int J Radiat Oncol Biol Phys 2007; 69:1282-9. [PMID: 17967318 DOI: 10.1016/j.ijrobp.2007.07.2333] [Citation(s) in RCA: 158] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2007] [Revised: 07/11/2007] [Accepted: 07/12/2007] [Indexed: 01/01/2023]
Abstract
PURPOSE Target-volume delineation for radiation treatment to the head and neck area traditionally is based on physical examination, computed tomography (CT), and magnetic resonance imaging. Additional molecular imaging with (18)F-fluoro-deoxy-glucose (FDG)-positron emission tomography (PET) may improve definition of the gross tumor volume (GTV). In this study, five methods for tumor delineation on FDG-PET are compared with CT-based delineation. METHODS AND MATERIALS Seventy-eight patients with Stages II-IV squamous cell carcinoma of the head and neck area underwent coregistered CT and FDG-PET. The primary tumor was delineated on CT, and five PET-based GTVs were obtained: visual interpretation, applying an isocontour of a standardized uptake value of 2.5, using a fixed threshold of 40% and 50% of the maximum signal intensity, and applying an adaptive threshold based on the signal-to-background ratio. Absolute GTV volumes were compared, and overlap analyses were performed. RESULTS The GTV method of applying an isocontour of a standardized uptake value of 2.5 failed to provide successful delineation in 45% of cases. For the other PET delineation methods, volume and shape of the GTV were influenced heavily by the choice of segmentation tool. On average, all threshold-based PET-GTVs were smaller than on CT. Nevertheless, PET frequently detected significant tumor extension outside the GTV delineated on CT (15-34% of PET volume). CONCLUSIONS The choice of segmentation tool for target-volume definition of head and neck cancer based on FDG-PET images is not trivial because it influences both volume and shape of the resulting GTV. With adequate delineation, PET may add significantly to CT- and physical examination-based GTV definition.
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Affiliation(s)
- Dominic A X Schinagl
- Department of Radiation Oncology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
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van Dalen JA, Hoffmann AL, Dicken V, Vogel WV, Wiering B, Ruers TJ, Karssemeijer N, Oyen WJG. A novel iterative method for lesion delineation and volumetric quantification with FDG PET. Nucl Med Commun 2007; 28:485-93. [PMID: 17460540 DOI: 10.1097/mnm.0b013e328155d154] [Citation(s) in RCA: 95] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVES The determination of lesion boundaries on FDG PET is difficult due to the point-spread blurring and unknown uptake of activity within a lesion. Standard threshold-based methods for volumetric quantification on PET usually neglect any size dependence and are biased by dependence on the signal-to-background ratio (SBR). A novel, model-based method is hypothesized to provide threshold levels independent f the SBR and to allow accurate measurement of volumes down to the resolution of the PET scanner. METHODS A background-subtracted relative-threshold level (RTL) method was derived, based on a convolution of the point-spread function and a sphere with diameter D. Validation of the RTL method was performed using PET imaging of a Jaszczak phantom with seven hollow spheres (D=10-60 mm). Activity concentrations for the background and spheres (signal) were varied to obtain SBRs of 1.5-10. An iterative procedure was introduced for volumetric quantification, as the optimal RTL depends on a priori knowledge of the volume. The feasibility of the RTL method was tested in two patients with liver metastases and compared to a standard method using a fixed percentage of the signal. RESULTS Phantom data validated that the theoretically optimal RTL depends on the sphere size, but not on the SBR. Typically, RTL=40% (D=15-60 mm), and RTL>50% for small spheres (D<12 mm). The RTL method is better applicable to patient data than the standard method. CONCLUSIONS Based on an iterative procedure, the RTL method has been shown to provide optimal threshold levels independent of the SBR and to be applicable in phantom and in patient studies. It is a promising tool for lesion delineation and volumetric quantification of PET lesions.
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Affiliation(s)
- Jorn A van Dalen
- Department of Nuclear Medicine, Radboud University Nijmegen Medical Centre, the Netherlands.
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