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Mishra A, Pathak R, Mittal KK, Srivastava AK, Dayashankar MS, Mishra SP, Singh SK. Efficacy of the collapsed cone algorithm calculated radiotherapy plans in intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT): A comparative dosimetric study in tumors of thorax. J Cancer Res Ther 2024; 20:383-388. [PMID: 38554350 DOI: 10.4103/jcrt.jcrt_2171_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 12/08/2022] [Indexed: 04/01/2024]
Abstract
AIM In this study, efficacy of collapsed cone algorithm-generated intensity-modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) were evaluated for treatment of thoracic esophageal cancer. MATERIALS AND METHODS Ten previously treated patients with VMAT were considered for evaluation. The planning parameters were evaluated in terms of max dose, mean dose, Homogeneity Index, Conformity Index for planning target volume, and organ at risk doses. Total monitor unit, treatment time, and gamma passing index were also reported. RESULTS The target dose coverage of the VMAT and IMRT plans achieved the clinical dosimetric criteria for all ten patients in the evaluation. Under the condition of equivalent target dose distribution, the VMAT plan's Conformity Index, monitor unit, treatment time, and gamma passing index rate were superior than in the IMRT plan, and the result was statistically significant. CONCLUSION Collapsed cone algorithm-based VMAT can have a more effective and better approach for esophageal cancer than IMRT.
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Affiliation(s)
- Atul Mishra
- Department of Physics, Tilak Dhari P. G. College, Jaunpur, Uttar Pradesh, India
- Veer Bahadur Singh Purvanchal University, Jaunpur, Uttar Pradesh, India
- Department of Radiation Oncology, Uttar Pradesh University of Medical Sciences, Saifai, Etawah, Uttar Pradesh, India
| | - Ramji Pathak
- Department of Physics, Tilak Dhari P. G. College, Jaunpur, Uttar Pradesh, India
- Veer Bahadur Singh Purvanchal University, Jaunpur, Uttar Pradesh, India
- Department of Physics, D.A.V. Degree College, Lucknow, Uttar Pradesh, India
| | - Kailash Kumar Mittal
- Department of Radiation Oncology, Uttar Pradesh University of Medical Sciences, Saifai, Etawah, Uttar Pradesh, India
| | - Anoop Kumar Srivastava
- Department of Radiation Oncology, Dr. Ram Manohar Lohia Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
| | - Maurya Surendrakumar Dayashankar
- Department of Applied Physics, Amity University Gwalior, Madhya Pradesh, India
- Department of Radiation Oncology, Shalby Hospitals Indore, Madhya Pradesh, India
| | - Surendra Prasad Mishra
- Department of Radiation Oncology, Dr. Ram Manohar Lohia Institute of Medical Sciences, Lucknow, Uttar Pradesh, India
| | - Sudesh Kumar Singh
- Department of Physics, Tilak Dhari P. G. College, Jaunpur, Uttar Pradesh, India
- Veer Bahadur Singh Purvanchal University, Jaunpur, Uttar Pradesh, India
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Jiao S, Zhao X, Yao S. Prediction of dose deposition matrix using voxel features driven machine learning approach. Br J Radiol 2023; 96:20220373. [PMID: 36856129 PMCID: PMC10161919 DOI: 10.1259/bjr.20220373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Revised: 02/05/2023] [Accepted: 02/12/2023] [Indexed: 03/02/2023] Open
Abstract
OBJECTIVES A dose deposition matrix (DDM) prediction method using several voxel features and a machine learning (ML) approach is proposed for plan optimization in radiation therapy. METHODS Head and lung cases with the inhomogeneous medium are used as training and testing data. The prediction model is a cascade forward backprop neural network where the input is the features of the voxel, including 1) voxel to body surface distance along the beamlet axis, 2) voxel to beamlet axis distance, 3) voxel density, 4) heterogeneity corrected voxel to body surface distance, 5) heterogeneity corrected voxel to beamlet axis, and (6) the dose of voxel obtained from the pencil beam (PB) algorithm. The output is the predicted voxel dose corresponding to a beamlet. The predicted DDM was used for plan optimization (ML method) and compared with the dose of MC-based plan optimization (MC method) and the dose of pencil beam-based plan optimization (PB method). The mean absolute error (MAE) value was calculated for full volume relative to the dose of the MC method to evaluate the overall dose performance of the final plan. RESULTS For patient with head tumor, the ML method achieves MAE value 0.49 × 10-4 and PB has MAE 1.86 × 10-4. For patient with lung tumor, the ML method has MAE 1.42 × 10-4 and PB has MAE 3.72 × 10-4. The maximum percentage difference in PTV dose coverage (D98) between ML and MC methods is no more than 1.2% for patient with head tumor, while the difference is larger than 10% using the PB method. For patient with lung tumor, the maximum percentage difference in PTV dose coverage (D98) between ML and MC methods is no more than 2.1%, while the difference is larger than 16% using the PB method. CONCLUSIONS In this work, a reliable DDM prediction method is established for plan optimization by applying several voxel features and the ML approach. The results show that the ML method based on voxel features can obtain plans comparable to the MC method and is better than the PB method in achieving accurate dose to the patient, which is helpful for rapid plan optimization and accurate dose calculation. ADVANCES IN KNOWLEDGE Establishment of a new machine learning method based on the relationship between the voxel and beamlet features for dose deposition matrix prediction in radiation therapy.
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Affiliation(s)
- Shengxiu Jiao
- Department of Nuclear Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Xiaoqian Zhao
- Department of Nuclear Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
| | - Shuzhan Yao
- Department of Nuclear Medicine, Shandong Provincial Hospital Affiliated to Shandong First Medical University, Jinan, Shandong, China
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Visser S, den Otter LA, Ribeiro CO, Korevaar EW, Both S, Langendijk JA, Muijs CT, Sijtsema NM, Knopf A. Diaphragm-Based Position Verification to Improve Daily Target Dose Coverage in Proton and Photon Radiation Therapy Treatment of Distal Esophageal Cancer. Int J Radiat Oncol Biol Phys 2021; 112:463-474. [PMID: 34530091 DOI: 10.1016/j.ijrobp.2021.09.015] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2020] [Revised: 08/21/2021] [Accepted: 09/06/2021] [Indexed: 12/23/2022]
Abstract
PURPOSE In modern conformal radiation therapy of distal esophageal cancer, target coverage can be affected by variations in the diaphragm position. We investigated if daily position verification (PV) extended by a diaphragm position correction would optimize target dose coverage for esophageal cancer treatment. METHODS AND MATERIALS For 15 esophageal cancer patients, intensity modulated proton therapy (IMPT) and volumetric modulated arc therapy (VMAT) plans were computed. Displacements of the target volume were correlated with diaphragm displacements using repeated 4-dimensional computed tomography images to determine the correction needed to account for diaphragm variations. Afterwards, target coverage was evaluated for 3 PV approaches based on: (1) bony anatomy (PV_B), (2) bony anatomy corrected for the diaphragm position (PV_BD) and (3) target volume (PV_T). RESULTS The cranial-caudal mean target displacement was congruent with almost half of the diaphragm displacement (y = 0.459x), which was used for the diaphragm correction in PV_BD. Target dose coverage using PV_B was adequate for most patients with diaphragm displacements up till 10 mm (≥94% of the dose in 98% of the volume [D98%]). For larger displacements, the target coverage was better maintained by PV_T and PV_BD. Overall, PV_BD accounted best for target displacements, especially in combination with tissue density variations (D98%: IMPT 94% ± 5%, VMAT 96% ± 5%). Diaphragm displacements of more than 10 mm were observed in 22% of the cases. CONCLUSIONS PV_B was sufficient to achieve adequate target dose coverage in case of small deviations in diaphragm position. However, large deviations of the diaphragm were best mitigated by PV_BD. To detect the cases where target dose coverage could be compromised due to diaphragm position variations, we recommend monitoring of the diaphragm position before treatment through online imaging.
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Affiliation(s)
- Sabine Visser
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands.
| | - Lydia A den Otter
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Cássia O Ribeiro
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Erik W Korevaar
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Stefan Both
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Johannes A Langendijk
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Christina T Muijs
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Nanna M Sijtsema
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
| | - Antje Knopf
- Department of Radiation Oncology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands
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Lao Z, Bi F, Fan W, Xu X, Tu W, Shi H. Noncoplanar Versus Coplanar Intensity-Modulated Radiation Therapy (IMRT) for Protection of the Lip and Buccal Mucosa. Technol Cancer Res Treat 2021; 20:15330338211019511. [PMID: 34044671 PMCID: PMC8165526 DOI: 10.1177/15330338211019511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Objective: In this study, by comparing coplanar and noncoplanar intensity-modulated radiation therapy (IMRT) treatment planning in treating tongue cancer, the significance of noncoplanar fields in the protection of the lip and buccal mucosa was determined, and a reasonable solution was selected. Methods: Forty-eight tongue cancer patients treated from June 2019 to February 2021 were selected and randomly divided into a coplanar field group and a noncoplanar field group. The mucosal dose limit changed from 15 Gy to 45 Gy for comparison of the two treatment plans. The evaluation indicators (conformal index (CI); homogeneity index (HI); D5, D50, and D98 of the target volume; and the dose of normal tissues) were calculated under different mucosal dose limits. The clinical observation of the lip and buccal mucosa of 48 cases was monitored and graded carefully according to NCI-CTCAE V4.0. Statistical analyses were performed. Results: The differences in CI, HI, D98, D50 and D5 between the two groups in the target volume tended to decrease when the mucosal dose limit was less than 30 Gy, with a significant difference (P < 0.05). When the limit exceeded 30 Gy, significant differences in other indicators except CI (P < 0.05) were still noted. In normal tissue, differences in doses between the two groups existed when the mucosal limit was less than 20 Gy, with a significant difference (P < 0.05). When the limit exceeded 20 Gy, no significant difference was noted. Patients in the noncoplanar group showed significantly better results than those in the other group in terms of the radiation-related toxicity of the lip and cheek membrane(P < 0.001). Conclusions: Compared with coplanar field radiotherapy, noncoplanar field radiotherapy can effectively reduce the exposure dose to the lip and buccal mucosa. The application of noncoplanar treatment plans exhibits good clinical significance and deserves to be promoted.
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Affiliation(s)
- Zheng Lao
- Department of Oral Maxillofacial Head and Neck Oncology, 56695Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, Shanghai China.,National Clinical Research Center of Oral Diseases, Shanghai, Shanghai China.,Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, Shanghai China
| | - Fan Bi
- Department of Oral Maxillofacial Head and Neck Oncology, 56695Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, Shanghai China.,National Clinical Research Center of Oral Diseases, Shanghai, Shanghai China.,Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, Shanghai China
| | - Wenhui Fan
- Department of Oral Maxillofacial Head and Neck Oncology, 56695Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, Shanghai China.,National Clinical Research Center of Oral Diseases, Shanghai, Shanghai China.,Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, Shanghai China
| | - Xuanli Xu
- Department of Oral Maxillofacial Head and Neck Oncology, 56695Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, Shanghai China.,National Clinical Research Center of Oral Diseases, Shanghai, Shanghai China.,Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, Shanghai China
| | - Wenyong Tu
- Department of Oral Maxillofacial Head and Neck Oncology, 56695Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, Shanghai China.,National Clinical Research Center of Oral Diseases, Shanghai, Shanghai China.,Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, Shanghai China
| | - Huifeng Shi
- Department of Oral Maxillofacial Head and Neck Oncology, 56695Shanghai Ninth People's Hospital, College of Stomatology, Shanghai Jiao Tong University School of Medicine, Shanghai, Shanghai China.,National Clinical Research Center of Oral Diseases, Shanghai, Shanghai China.,Shanghai Key Laboratory of Stomatology & Shanghai Research Institute of Stomatology, Shanghai, Shanghai China
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Raturi VP, Motegi A, Zenda S, Nakamura N, Hojo H, Kageyama SI, Okumura M, Rachi T, Ohyoshi H, Tachibana H, Motegi K, Ariji T, Nakamura M, Hirano Y, Hirata H, Akimoto T. Comparison of a Hybrid IMRT/VMAT technique with non-coplanar VMAT and non-coplanar IMRT for unresectable olfactory neuroblastoma using the RayStation treatment planning system-EUD, NTCP and planning study. JOURNAL OF RADIATION RESEARCH 2021; 62:540-548. [PMID: 33839761 PMCID: PMC8127663 DOI: 10.1093/jrr/rrab010] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Revised: 01/20/2021] [Indexed: 06/12/2023]
Abstract
The purpose of this study was to compare hybrid intensity-modulated radiotherapy (IMRT) and volumetric-modulated arc therapy (Hybrid IMRT/VMAT), with non-coplanar (nc) IMRT and nc-VMAT treatment plans for unresectable olfactory neuroblastoma (ONB). Hybrid IMRT/VMAT, nc-IMRT and nc-VMAT plans were optimized for 12 patients with modified Kadish C stage ONB. Dose prescription was 65 Gy in 26 fractions. Dose-volume histogram parameters, conformation number (CN), homogeneity index (HI), integral dose and monitor units (MUs) delivered per fraction were assessed. Equivalent uniform dose (EUD) and normal tissue complication probability (NTCP) based on the EUD model (NTCPLogit) and the Lyman-Kutcher-Burman model (NTCPLKB) were also evaluated. We found that the Hybrid IMRT/VMAT plan significantly improved the CN for clinical target volume (CTV) and planning treatment volume (PTV) compared with the nc-VMAT plan. In general, sparing of organs at risk (OARs) is similar with the three techniques, although the Hybrid IMRT/VMAT plan resulted in a significantly reduced Dmax to contralateral (C/L) optic nerve compared with the nc-IMRT plan. The Hybrid IMRT/VMAT plan significantly reduce EUD to the ipsilateral (I/L) and C/L optic nerve in comparison with the nc-IMRT plan and nc-VMAT plan, but the difference in NTCP between the three technique was <1%. We concluded that the Hybrid IMRT/VMAT technique can offer improvement in terms of target conformity and EUD for optic nerves, while achieving equal or better OAR sparing compared with nc-IMRT and nc-VMAT, and can be a viable radiation technique for treating unresectable ONB. However, the clinical benefit of these small differences in dosimetric data, EUD and NTCP of optic nerves may be minimal.
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Affiliation(s)
- Vijay P Raturi
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
- Course of Advanced Clinical Research of Cancer, Graduate School of Medicine, Juntendo University, Tokyo, Japan
| | - Atsushi Motegi
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Sadamoto Zenda
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Naoki Nakamura
- Department of Radiology, St. Marianna University School of Medicine, Kawasaki, Japan
| | - Hidehiro Hojo
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Shin-Ichiro Kageyama
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Masayuki Okumura
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Toshiya Rachi
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Hajime Ohyoshi
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Hidenobu Tachibana
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Kana Motegi
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Takaki Ariji
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Masaki Nakamura
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Yasuhiro Hirano
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Hidenari Hirata
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
| | - Tetsuo Akimoto
- Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, Kashiwa, Chiba, Japan
- Course of Advanced Clinical Research of Cancer, Graduate School of Medicine, Juntendo University, Tokyo, Japan
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Effect of lung volume on helical radiotherapy in esophageal cancer: are there predictive factors to achieve acceptable lung doses? Strahlenther Onkol 2020; 196:805-812. [PMID: 31980833 DOI: 10.1007/s00066-020-01581-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 01/07/2020] [Indexed: 12/25/2022]
Abstract
PURPOSE The dose received by the lungs in radiotherapy (RT) is affected by the patient's current lung volume. The presence of predictive factors and cut-off points were investigated to achieve acceptable lung doses in esophageal cancer (EC) treatment. METHODS Virtual RT volumes of supracarinal EC were delineated. RT plans were designed with standard criteria in the TomoTherapy planning system (TomoTherapy Inc., Madison, WI, USA). The total dose was 50.4 Gy (1.8 Gy/fraction). ROC (Receiver operating characteristic) analysis and Mann-Whitney U tests were performed. RESULTS There was a total of 65 patient plans included. ROC analysis showed that lung/PTV (Planning target volume) volume ratio (AUC [Area under curve]: 0.91, 95% CI: 0.83-0.99, p = 0.000) and bilateral lung volume (AUC: 0.81, 95% CI: 0.70-0.92, p = 0.000) have diagnostic power to predict the suitability of RT plans according to QUANTEC (Quantitative Analyses of Normal Tissue Effects in the Clinic) for lung dose constraints. The cut-off points of 7 and 3500 cc were selected for lung/PTV ratio and bilateral lung volume, respectively. The effect of the cut-off points on the dose data was assessed with the Mann-Whitney U test. The mean lung and heart doses, lung V5, V15, and V20, as well as heart V5, V20, V30, and V45 values were found to be lower in both groups separated by cut-off points (p < 0.05). CONCLUSION The lung/PTV ratio ≥7 and bilateral lung volume ≥3500 cc cut-off points are predictive of whether TomoTherapy plans may meet QUANTEC lung dose limits in patients with supracarinal esophageal cancer. The patients with lung/PTV ratio and lung volume above these cut-off points may be candidates for treatment with TomoTherapy.
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Wang L, Li C, Meng X, Li C, Sun X, Shang D, Pang L, Li Y, Lu J, Yu J. Dosimetric and Radiobiological Comparison of External Beam Radiotherapy Using Simultaneous Integrated Boost Technique for Esophageal Cancer in Different Location. Front Oncol 2019; 9:674. [PMID: 31404144 PMCID: PMC6669560 DOI: 10.3389/fonc.2019.00674] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Accepted: 07/10/2019] [Indexed: 12/25/2022] Open
Abstract
Objectives: To compare treatment plans of intensity modulated radiotherapy (IMRT), volumetric modulated arc radiotherapy (VMAT), and helical tomotherapy (HT) with simultaneous integrated boost (SIB) technique for esophageal cancer (EC) of different locations using dosimetry and radiobiology. Methods: Forty EC patients were planned for IMRT, VMAT, and HT plans, including 10 cases located in the cervix, upper, middle, and lower thorax, respectively. Dose-volume metrics, conformity index (CI), homogeneity index (HI), tumor control probability (TCP), and normal tissue complication probability (NTCP) were analyzed to evaluate treatment plans. Results: HT showed significant improvement over IMRT and VMAT in terms of CI (p = 0.007), HI (p < 0.001), and TCP (p < 0.001) in cervical EC. IMRT yielded more superior CI, HI and TCP compared with VMAT and HT in upper and middle thoracic EC (all p < 0.05). Additionally, V30 (27.72 ± 8.67%), mean dose (1801.47 ± 989.58cGy), and NTCP (Niemierko model: 0.44 ± 0.55%; Lyman-Kutcher-Burman model: 0.61 ± 0.59%) of heart in IMRT were sharply reduced than VMAT and HT in middle thoracic EC. For lower thoracic EC, the three techniques offered similar CI and HI (all p > 0.05). But VMAT dramatically lowered liver V30 (9.97 ± 2.84%), and reduced NTCP of lungs (Niemierko model: 0.47 ± 0.48%; Lyman-Kutcher-Burman model: 1.41 ± 1.07%) and liver (Niemierko model: 0.10 ± 0.08%; Lyman-Kutcher-Burman model: 0.17 ± 0.17%). Conclusions: HT was a good option for cervical EC with complex target coverage but little lungs and heart involvement as it achieved superior dose conformity and uniformity. Due to potentially improving tumor control and reducing heart dose with acceptable lungs sparing, IMRT was a preferred choice for upper and middle thoracic EC with large lungs involvement. VMAT could ameliorate therapeutic ratio and lower lungs and liver toxicity, which was beneficial for lower thoracic EC with little thoracic involvement but being closer to heart and liver. Individually choosing optimal technique for EC in different location will be warranted.
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Affiliation(s)
- Lu Wang
- Department of Radiation Oncology, School of Medicine, Shandong University, Jinan, China.,Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Chengqiang Li
- Department of Radiation Physics, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Xue Meng
- Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Chengming Li
- Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Xindong Sun
- Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Dongping Shang
- Department of Radiation Physics, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Linlin Pang
- Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Yixiao Li
- Department of Clinical Medicine, Jining Medical University, Jining, China
| | - Jie Lu
- Department of Radiation Physics, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
| | - Jinming Yu
- Department of Radiation Oncology, School of Medicine, Shandong University, Jinan, China.,Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Shandong First Medical University and Shandong Academy of Medical Sciences, Jinan, China
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8
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Giannetta E, Guarnotta V, Rota F, de Cicco F, Grillo F, Colao A, Faggiano A. A rare rarity: Neuroendocrine tumor of the esophagus. Crit Rev Oncol Hematol 2019; 137:92-107. [PMID: 31014519 DOI: 10.1016/j.critrevonc.2019.02.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 08/08/2018] [Accepted: 02/26/2019] [Indexed: 01/09/2023] Open
Abstract
Esophageal Neuroendocrine tumors (NETs) are rare, aggressive and lacking specific symptoms. This causes a diagnostic delay, worsening the prognosis. Numerous cases are reported in literature, without a consensus on the management. Our aim was to clarify epidemiology, clinical presentation, diagnostic, therapeutic management of esophageal NETs. Extensive literature search identified a total of 226 articles. One hundred twenty-five articles (n = 1676) met the inclusion criteria, showing that: the incidence of esophageal NET varies geographically; men (60-70 years) are more affected; smoking and alcohol abuse are the major risk factors; dysphagia, weight loss, appetite loss are the most common clinical features. The histotypes include high-grade small and large cell esophageal carcinomas and low-grade carcinoid tumors. Mixed neuroendocrine/non-neuroendocrine neoplasms are the most common. Often the diagnosis occurs randomly on endoscopic examination. Circulating markers, functional combined with conventional imaging contributes to the diagnosis and management. Treatment depends on type, grade and stage of the tumor.
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Affiliation(s)
- Elisa Giannetta
- Dept. of Experimental Medicine, "Sapienza" University of Rome, Italy.
| | - Valentina Guarnotta
- Biomedical Department of Internal and Specialist Medicine (DIBIMIS), Section of Endocrine-Metabolic Diseases, University of Palermo, Italy
| | - Francesca Rota
- Unit of Endocrinology, San Camillo-Forlanini Hospital, Rome, Italy
| | - Federica de Cicco
- Department of Clinical Medicine and Surgery, University "Federico II", Naples, Italy
| | - Federica Grillo
- Pathology Unit, Department of Surgical Sciences and Integrated Diagnostics (DISC), University of Genova and Ospedale Policlinico San Martino, Genova, Italy
| | - Annamaria Colao
- Department of Clinical Medicine and Surgery, University "Federico II", Naples, Italy
| | - Antongiulio Faggiano
- Thyroid and Parathyroid Surgery Unit, Istituto Nazionale per lo Studio e la Cura dei Tumori "Fondazione G. Pascale", IRCCS, Naples, Italy
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9
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Zhang Y, Wang H, Huang X, Zhang Q, Ren R, Sun R, Zheng Z, Dong S, Zheng A. Dosimetric comparison of TomoDirect, helical tomotherapy, VMAT, and ff-IMRT for upper thoracic esophageal carcinoma. Med Dosim 2018; 44:167-172. [PMID: 29950277 DOI: 10.1016/j.meddos.2018.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 03/08/2018] [Accepted: 05/14/2018] [Indexed: 12/25/2022]
Abstract
BACKGROUND The new TomoDirect (TD) modality offers a nonrotational option with discrete beam angles. We aim to compare dosimetric parameters of TD, helical tomotherapy (HT), volumetric-modulated arc therapy (VMAT), and fixed-field intensity-modulated radiotherapy (ff-IMRT) for upper thoracic esophageal carcinoma (EC). METHODS Twenty patients with cT2-4N0-1M0 upper thoracic esophageal squamous cell carcinoma (ESCC) were enrolled. Four plans were generated using the same dose objectives for each patient: TD, HT, VMAT with a single arc, and ff-IMRT with 5 fields (5F). The prescribed doses were used to deliver 50.4 Gy/28F to the planning target volume (PTV50.4) and then provided a 9 Gy/5F boost to PTV59.4. Dose-volume histogram (DVH) statistics, dose uniformity, and dose homogeneity were analyzed to compare treatment plans. RESULTS For PTV59.4, the D2, D98, Dmean, and V100% values in HT were significantly lower than other plans (all p < 0.05), and those in TD were significantly lower than VMAT and ff-IMRT (all p < 0.05). However, there was no significant difference in the D2 and Dmean values between VMAT and ff-IMRT techniques (p > 0.05). The homogeneity index (HI) differed significantly for the 4 techniques of TD, HT, VMAT, and ff-IMRT (0.03 ± 0.01, 0.02 ± 0.01, 0.06 ± 0.02, and 0.05 ± 0.01, respectively; p < 0.001). The HI for TD was similar to HT (p = 0.166), and had statistically significant improvement compared to VMAT (p < 0.001) and ff-IMRT (p = 0.003). In comparison with the 4 conformity indices (CIs), there was no significant difference (p > 0.05). For PTV50.4, the D2 and Dmean values in HT were significantly lower than other plans (all p < 0.05), and those in TD were significantly lower than VMAT and ff-IMRT (all p < 0.05). However, there was no significant difference in the D2 and Dmean values between VMAT and ff-IMRT techniques (p > 0.05). No D98 and V100% parameters differed significantly among the 4 treatment types (p > 0.05). HT plans were provided for statistically significant improvement in HI (0.03 ± 0.01) compared to TD plans (0.05 ± 0.01, p = 0.003), VMAT (0.08 ± 0.03, p < 0.001), ff-IMRT (0.08 ± 0.01, p < 0.001). The HI revealed that TD was superior to VMAT and ff-IMRT (p < 0.05). The CI differed significantly for the 4 techniques of TD, HT, VMAT, and ff-IMRT (0.59 ± 0.10, 0.69 ± 0.11, 0.64 ± 0.09, and 0.64 ± 0.11, respectively; p = 0.035). The best CI was yielded by HT. We found no significant difference for the V5, V10, V15, V30, and the mean lung dose (MLD) among the 4 techniques (all p > 0.05). However, the V20 differed significantly among TD, HT, VMAT, and ff-IMRT (21.50 ± 7.20%, 19.50 ± 5.55%, 17.65 ± 5.45%, and 16.35 ± 5.70%, respectively; p = 0.047). Average V20 for the lungs was significantly improved by the TD plans compared to VMAT (p = 0.047), and ff-IMRT (p = 0.008). The V5 value of the lung in TD was 49.30 ± 13.01%, lower than other plans, but there was no significant difference (p > 0.05). The D1 of the spinal cord showed no significant difference among the 4 techniques (p = 0.056). CONCLUSIONS All techniques are able to provide a homogeneous and highly conformal dose distribution. The TD technique is a good option for treating upper thoracic EC involvement. It could achieve optimal low dose to the lungs and spinal cord with acceptable PTV coverage. HT is a good option as it could achieve quality dose conformality and uniformity, while TD generated superior conformality.
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Affiliation(s)
- Yaowen Zhang
- Department of Radiation Oncology, Anyang Cancer Hospital, Anyang, Henan, China
| | - Huitao Wang
- Department of Radiation Oncology, Anyang Cancer Hospital, Anyang, Henan, China
| | - Xiao Huang
- Department of Radiation Oncology, Anyang Cancer Hospital, Anyang, Henan, China
| | - Qiang Zhang
- Department of Radiation Oncology, Anyang Cancer Hospital, Anyang, Henan, China
| | - Runchuan Ren
- Department of Radiation Oncology, Anyang Cancer Hospital, Anyang, Henan, China
| | - Ronggang Sun
- Department of Radiation Oncology, Anyang Cancer Hospital, Anyang, Henan, China
| | - Zhiyong Zheng
- Department of Radiation Oncology, Anyang Cancer Hospital, Anyang, Henan, China
| | - Shangwen Dong
- Department of Cardiothoracic Surgery, Tianjin Medical University General Hospital, Tianjin, China.
| | - Anping Zheng
- Department of Radiation Oncology, Anyang Cancer Hospital, Anyang, Henan, China.
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10
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Efficacy of virtual block objects in reducing the lung dose in helical tomotherapy planning for cervical oesophageal cancer: a planning study. Radiat Oncol 2018; 13:62. [PMID: 29618353 PMCID: PMC5885420 DOI: 10.1186/s13014-018-1012-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 03/26/2018] [Indexed: 12/03/2022] Open
Abstract
Background Intensity-modulated radiotherapy is useful for cervical oesophageal carcinoma (CEC); however, increasing low-dose exposure to the lung may lead to radiation pneumonitis. Nevertheless, an irradiation technique that avoids the lungs has never been examined due to the high difficulty of dose optimization. In this study, we examined the efficacy of helical tomotherapy that can restrict beamlets passing virtual blocks during dose optimization computing (block plan) in reducing the lung dose. Methods Fifteen patients with CEC were analysed. The primary/nodal lesion and prophylactic nodal region with adequate margins were defined as the planning target volume (PTV)-60 Gy and PTV-48 Gy, respectively. Nineteen plans per patient were made and compared (total: 285 plans), including non-block and block plans with several shapes and sizes. Results The most appropriate block model was semi-circular, 8 cm outside of the tracheal bifurcation, with a significantly lower lung dose compared to that of non-block plans; the mean lung volumes receiving 5 Gy, 10 Gy, 20 Gy, and the mean lung dose were 31.3% vs. 48.0% (p < 0.001), 22.4% vs. 39.4% (p < 0.001), 13.2% vs. 16.0% (p = 0.028), and 7.1 Gy vs. 9.6 Gy (p < 0.001), respectively. Both the block and non-block plans were comparable in terms of the homogeneity and conformity indexes of PTV-60 Gy: 0.05 vs. 0.04 (p = 0.100) and 0.82 vs. 0.85 (p = 0.616), respectively. The maximum dose of the spinal cord planning risk volume increased slightly (49.4 Gy vs. 47.9 Gy, p = 0.002). There was no significant difference in the mean doses to the heart and the thyroid gland. Prolongation of the delivery time was less than 1 min (5.6 min vs. 4.9 min, p = 0.010). Conclusions The block plan for CEC could significantly reduce the lung dose, with acceptable increment in the spinal dose and a slightly prolonged delivery time.
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11
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Li J, To D, Gunn V, Shi W, Yu Y, Liu H. Evaluation of Hybrid Arc and Volumetric-Modulated Arc Therapy Treatment Plans for Fractionated Stereotactic Intracranial Radiotherapy. Technol Cancer Res Treat 2018; 17:1533033818802804. [PMID: 30343652 PMCID: PMC6198396 DOI: 10.1177/1533033818802804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Purpose: The study was aimed to compare hybrid arc and volumetric-modulated arc therapy treatment plans for fractionated stereotactic radiotherapy of brain tumors. Methods: Treatment plans of 22 patients were studied. Hybrid arc and volumetric-modulated arc therapy plans were generated using Brainlab iPlanDose and Varian Eclipse treatment planning systems, respectively, with 6 MV photon beams on a Varian TrueBeam STx linear accelerator (Palo Alto, CA). Prescription dose was 54 Gy. The fractionation was 1.8 Gy per fraction and 30 fractions in total, or 2 Gy per fraction and 27 fractions in total. Planning target volume ranged from 2.4 to 28.6 cm3. Dose conformity index, gradient index, homogeneity index, and maximum doses in organs at risk were compared. Wilcoxon signed rank test was used to determine statistical significance in paired comparison. Results: Conformity indexes of hybrid arc and volumetric-modulated arc therapy plans are 1.10 ± 0.10 and 1.14 ± 0.07, respectively (P = .4); gradient indexes are 5.02 ± 1.20 and 5.64 ± 1.28, respectively (P = .0001); homogeneity indexes are 1.02 ± 0.01 and 1.05 ± 0.01, respectively (P = .0001); brainstem maximum doses are 53.87 ± 1.63 Gy and 54.06 ± 3.17 Gy, respectively (P = .1); and optic chiasm maximum doses are 53.86 ± 1.28 Gy and 53.95 ± 1.81, respectively (P = .4). The monitor unit efficiencies of hybrid arc and volumetric-modulated arc therapy plans are 2.57 ± 0.25 MU/cGy and 2.68 ± 0.24 MU/cGy, respectively (P = .2). The differences of conformity index, gradient index, and homogeneity index between hybrid arc and volumetric-modulated arc therapy plans are small: 0.08 ± 0.05, 0.65 ± 0.46, and 0.02 ± 0.01, respectively. The maximum doses in organs at risks are similar between hybrid arc and volumetric-modulated arc therapy plans. Hybrid arc and volumetric-modulated arc therapy plans, which have similar monitor unit efficiencies, present similar dosimetric results in the fractionated intracranial radiotherapy.
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Affiliation(s)
- Jun Li
- 1 Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA, USA
| | - David To
- 1 Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Vickie Gunn
- 1 Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Wenyin Shi
- 1 Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Yan Yu
- 1 Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA, USA
| | - Haisong Liu
- 1 Department of Radiation Oncology, Thomas Jefferson University, Philadelphia, PA, USA
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12
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Chen H, Wang H, Gu H, Shao Y, Cai X, Fu X, Xu Z. Study for reducing lung dose of upper thoracic esophageal cancer radiotherapy by auto-planning: volumetric-modulated arc therapy vs intensity-modulated radiation therapy. Med Dosim 2017; 43:243-250. [PMID: 29110926 DOI: 10.1016/j.meddos.2017.09.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2017] [Revised: 09/11/2017] [Accepted: 09/14/2017] [Indexed: 12/25/2022]
Abstract
This study aimed to investigate the dosimetric differences and lung sparing between volumetric-modulated arc therapy (VMAT) and intensity-modulated radiation therapy (IMRT) in the treatment of upper thoracic esophageal cancer with T3N0M0 for preoperative radiotherapy by auto-planning (AP). Sixteen patient cases diagnosed with upper thoracic esophageal cancer T3N0M0 for preoperative radiotherapy were retrospectively studied, and 3 plans were generated for each patient: full arc VMAT AP plan with double arcs, partial arc VMAT AP plan with 6 partial arcs, and conventional IMRT AP plan. A simultaneous integrated boost with 2 levels was planned in all patients. Target coverage, organ at risk sparing, treatment parameters including monitor units and treatment time (TT) were evaluated. Wilcoxon signed-rank test was used to check for significant differences (p < 0.05) between datasets. VMAT plans (pVMAT and fVMAT) significantly reduced total lung volume treated above 20 Gy (V20), 25 Gy (V25), 30 Gy (V30), 35 Gy (V35), 40 Gy (V40), and without increasing the value of V10, V13, and V15. For V5 of total lung value, pVMAT was similar to aIMRT, and it was better than fVMAT. Both pVMAT and fVMAT improved the target dose coverage and significantly decreased maximum dose for the spinal cord, monitor unit, and TT. No significant difference was observed with respect to V10 and V15 of body. VMAT AP plan was a good option for treating upper thoracic esophageal cancer with T3N0M0, especially partial arc VMAT AP plan. It had the potential to effectively reduce lung dose in a shorter TT and with superior target coverage and dose homogeneity.
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Affiliation(s)
- Hua Chen
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Hao Wang
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Hengle Gu
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Yan Shao
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Xuwei Cai
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Xiaolong Fu
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China
| | - Zhiyong Xu
- Department of Radiation Oncology, Shanghai Chest Hospital, Shanghai Jiao Tong University, Shanghai, China.
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13
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Hansen CR, Nielsen M, Bertelsen AS, Hazell I, Holtved E, Zukauskaite R, Bjerregaard JK, Brink C, Bernchou U. Automatic treatment planning facilitates fast generation of high-quality treatment plans for esophageal cancer. Acta Oncol 2017; 56:1495-1500. [PMID: 28840767 DOI: 10.1080/0284186x.2017.1349928] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
BACKGROUND The quality of radiotherapy planning has improved substantially in the last decade with the introduction of intensity modulated radiotherapy. The purpose of this study was to analyze the plan quality and efficacy of automatically (AU) generated VMAT plans for inoperable esophageal cancer patients. MATERIAL AND METHODS Thirty-two consecutive inoperable patients with esophageal cancer originally treated with manually (MA) generated volumetric modulated arc therapy (VMAT) plans were retrospectively replanned using an auto-planning engine. All plans were optimized with one full 6MV VMAT arc giving 60 Gy to the primary target and 50 Gy to the elective target. The planning techniques were blinded before clinical evaluation by three specialized oncologists. To supplement the clinical evaluation, the optimization time for the AU plan was recorded along with DVH parameters for all plans. RESULTS Upon clinical evaluation, the AU plan was preferred for 31/32 patients, and for one patient, there was no difference in the plans. In terms of DVH parameters, similar target coverage was obtained between the two planning methods. The mean dose for the spinal cord increased by 1.8 Gy using AU (p = .002), whereas the mean lung dose decreased by 1.9 Gy (p < .001). The AU plans were more modulated as seen by the increase of 12% in mean MUs (p = .001). The median optimization time for AU plans was 117 min. CONCLUSIONS The AU plans were in general preferred and showed a lower mean dose to the lungs. The automation of the planning process generated esophageal cancer treatment plans quickly and with high quality.
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Affiliation(s)
- Christian Rønn Hansen
- Laboratory of Radiation Physics, Odense University Hospital, Odense, Denmark
- Institute of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Morten Nielsen
- Laboratory of Radiation Physics, Odense University Hospital, Odense, Denmark
| | | | - Irene Hazell
- Laboratory of Radiation Physics, Odense University Hospital, Odense, Denmark
| | - Eva Holtved
- Department of Oncology, Odense University Hospital, Odense, Denmark
| | - Ruta Zukauskaite
- Institute of Clinical Research, University of Southern Denmark, Odense, Denmark
- Department of Oncology, Odense University Hospital, Odense, Denmark
| | - Jon Kroll Bjerregaard
- Institute of Clinical Research, University of Southern Denmark, Odense, Denmark
- Department of Oncology, Odense University Hospital, Odense, Denmark
| | - Carsten Brink
- Laboratory of Radiation Physics, Odense University Hospital, Odense, Denmark
- Institute of Clinical Research, University of Southern Denmark, Odense, Denmark
| | - Uffe Bernchou
- Laboratory of Radiation Physics, Odense University Hospital, Odense, Denmark
- Institute of Clinical Research, University of Southern Denmark, Odense, Denmark
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14
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Gu Q, Lai XJ, Yang SY, Feng W, Lin X, Yu XF, Zheng X. Dosimetric comparison between helical tomotherapy and intensity-modulated radiotherapy for esophageal carcinoma. PRECISION RADIATION ONCOLOGY 2017. [DOI: 10.1002/pro6.21] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Affiliation(s)
- Qing Gu
- Department of Radiation Oncology; Zhejiang Cancer Hospital (Zhejiang Cancer Research Institute); Gongshu District Hang zhou Zhejiang China
| | - Xiao-jing Lai
- Department of Radiation Oncology; Zhejiang Cancer Hospital (Zhejiang Cancer Research Institute); Gongshu District Hang zhou Zhejiang China
| | - Shuang-yan Yang
- Department of Radiation Oncology; Zhejiang Cancer Hospital (Zhejiang Cancer Research Institute); Gongshu District Hang zhou Zhejiang China
| | - Wei Feng
- Department of Radiation Oncology; Zhejiang Cancer Hospital (Zhejiang Cancer Research Institute); Gongshu District Hang zhou Zhejiang China
| | - Xiao Lin
- Department of Radiation Oncology; Zhejiang Cancer Hospital (Zhejiang Cancer Research Institute); Gongshu District Hang zhou Zhejiang China
| | - Xiao-fu Yu
- Department of Radiation Oncology; Zhejiang Cancer Hospital (Zhejiang Cancer Research Institute); Gongshu District Hang zhou Zhejiang China
| | - Xiao Zheng
- Department of Radiation Oncology; Zhejiang Cancer Hospital (Zhejiang Cancer Research Institute); Gongshu District Hang zhou Zhejiang China
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15
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Differding S, Sterpin E, Hermand N, Vanstraelen B, Nuyts S, de Patoul N, Denis JM, Lee JA, Grégoire V. Radiation dose escalation based on FDG-PET driven dose painting by numbers in oropharyngeal squamous cell carcinoma: a dosimetric comparison between TomoTherapy-HA and RapidArc. Radiat Oncol 2017; 12:59. [PMID: 28335778 PMCID: PMC5364636 DOI: 10.1186/s13014-017-0793-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2016] [Accepted: 03/01/2017] [Indexed: 12/31/2022] Open
Abstract
Purpose Validation of dose escalation through FDG-PET dose painting (DP) for oropharyngeal squamous cell carcinoma (SCC) requires randomized clinical trials with large sample size, potentially involving different treatment planning and delivery systems. As a first step of a joint clinical study of DP, a planning comparison was performed between Tomotherapy HiArt® (HT) and Varian RapidArc® (RA). Methods The planning study was conducted on five patients with oropharyngeal SCC. Elective and therapeutic CTVs were delineated based on anatomic information, and the respective PTVs (CTVs + 4 mm) were prescribed a dose of 56 (PTV56) and 70 Gy (PTV70). A gradient-based method was used to delineate automatically the external contours of the FDG-PET volume (GTVPET). Variation of the FDG uptake within the GTVPET was linearly converted into a prescription between 70 and 86 Gy. A dilation of the voxel-by-voxel prescription of 2.5 mm was applied to account for geometric errors in dose delivery (PTVPET). The study was divided in two planning phases aiming at maximizing target coverage (phase I) and lowering doses to OAR (phase II). A Quality-Volume Histogram (QVH) assessed conformity with the DP prescription inside the PTVPET. Results In phase I, for both HT and RA, all plans achieved comparable target coverage for PTV56 and PTV70, respecting the planning objectives. A median value of 99.9 and 97.2% of all voxels in the PTVPET received at least 95% of the prescribed dose for RA and HT, respectively. A median value of 0.0% and 3.7% of the voxels in the PTVPET received 105% or more of prescribed dose for RA and HT, respectively. In phase II, no significant differences were found in OAR sparing. Median treatment times were 13.7 min for HT and 5 min for RA. Conclusions Both HT and RA can generate similar dose distributions for FDG-PET based dose escalation and dose painting in oropharyngeal SCC patients. Electronic supplementary material The online version of this article (doi:10.1186/s13014-017-0793-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Sarah Differding
- Department of Radiation Oncology, and Center for Molecular Imaging, Oncology and Radiotherapy (MIRO), Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique (IREC), Brussels, Belgium
| | - Edmond Sterpin
- Department of Radiation Oncology, and Center for Molecular Imaging, Oncology and Radiotherapy (MIRO), Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique (IREC), Brussels, Belgium
| | - Nicolas Hermand
- Department of Oncology, Experimental Radiation Oncology, KU Leuven - University of Leuven, Leuven, Belgium
| | - Bianca Vanstraelen
- Department of Oncology, Experimental Radiation Oncology, KU Leuven - University of Leuven, Leuven, Belgium
| | - Sandra Nuyts
- Department of Oncology, Experimental Radiation Oncology, KU Leuven - University of Leuven, Leuven, Belgium.,Department of Radiation Oncology, University Hospitals Leuven, Leuven Cancer Institute, Leuven, Belgium
| | - Nathalie de Patoul
- Department of Radiation Oncology, St-Luc University Hospital, Avenue Hippocrate 10, B-1200, Bruxelles, Belgium
| | - Jean-Marc Denis
- Department of Radiation Oncology, St-Luc University Hospital, Avenue Hippocrate 10, B-1200, Bruxelles, Belgium
| | - John Aldo Lee
- Department of Radiation Oncology, and Center for Molecular Imaging, Oncology and Radiotherapy (MIRO), Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique (IREC), Brussels, Belgium
| | - Vincent Grégoire
- Department of Radiation Oncology, and Center for Molecular Imaging, Oncology and Radiotherapy (MIRO), Université catholique de Louvain, Institut de Recherche Expérimentale et Clinique (IREC), Brussels, Belgium. .,Department of Radiation Oncology, St-Luc University Hospital, Avenue Hippocrate 10, B-1200, Bruxelles, Belgium.
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16
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Chun SG, Skinner HD, Minsky BD. Radiation Therapy for Locally Advanced Esophageal Cancer. Surg Oncol Clin N Am 2017; 26:257-276. [PMID: 28279468 DOI: 10.1016/j.soc.2016.10.006] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The treatment of locally advanced esophageal cancer is controversial. For patients who are candidates for surgical resection, multiple prospective clinical trials have demonstrated the advantages of neoadjuvant chemoradiation. For patients who are medically inoperable, definitive chemoradiation is an alternative approach with survival rates comparable to trimodality therapy. Although trials of dose escalation are ongoing, the standard radiation dose remains 50.4 Gy. Modern radiotherapy techniques such as image-guided radiation therapy with motion management and intensity-modulated radiation therapy are strongly encouraged with a planning objective to maximize conformity to the intended target volume while reducing dose delivered to uninvolved normal tissues.
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Affiliation(s)
- Stephen G Chun
- Division of Radiation Oncology, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA.
| | - Heath D Skinner
- Division of Radiation Oncology, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
| | - Bruce D Minsky
- Division of Radiation Oncology, The University of Texas, M.D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, TX 77030, USA
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17
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Bedford JL, Smyth G, Hanson IM, Tree AC, Dearnaley DP, Hansen VN. Quality of treatment plans and accuracy of in vivo portal dosimetry in hybrid intensity-modulated radiation therapy and volumetric modulated arc therapy for prostate cancer. Radiother Oncol 2016; 120:320-6. [PMID: 27470308 DOI: 10.1016/j.radonc.2016.07.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2015] [Revised: 06/27/2016] [Accepted: 07/04/2016] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Delivering selected parts of volumetric modulated arc therapy (VMAT) plans using step-and-shoot intensity modulated radiotherapy (IMRT) beams has the potential to increase plan quality by allowing specific aperture positioning. This study investigates the quality of treatment plans and the accuracy of in vivo portal dosimetry in such a hybrid approach for the case of prostate radiotherapy. MATERIAL AND METHODS Conformal and limited-modulation VMAT plans were produced, together with five hybrid IMRT/VMAT plans, in which 0%, 25%, 50%, 75% or 100% of the segments were sequenced for IMRT, while the remainder were sequenced for VMAT. Integrated portal images were predicted for the plans. The plans were then delivered as a single hybrid beam using an Elekta Synergy accelerator with Agility head to a water-equivalent phantom and treatment time, isocentric dose and portal images were measured. RESULTS Increasing the IMRT percentage improves dose uniformity to the planning target volume (p<0.01 for 50% IMRT or more), substantially reduces the volume of rectum irradiated to 65Gy (p=0.02 for 25% IMRT) and increases the monitor units (p<0.001). Delivery time also increases substantially. All plans show accurate delivery of dose and reliable prediction of portal images. CONCLUSIONS Hybrid IMRT/VMAT can be efficiently planned and delivered as a single beam sequence. Beyond 25% IMRT, the delivery time becomes unacceptably long, with increased risk of intrafraction motion, but 25% IMRT is an attractive compromise. Integrated portal images can be used to perform in vivo dosimetry for this technique.
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Affiliation(s)
- James L Bedford
- The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK.
| | - Gregory Smyth
- The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Ian M Hanson
- The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Alison C Tree
- The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - David P Dearnaley
- The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
| | - Vibeke N Hansen
- The Institute of Cancer Research and The Royal Marsden NHS Foundation Trust, London, UK
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18
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Fogliata A, Nicolini G, Clivio A, Vanetti E, Laksar S, Tozzi A, Scorsetti M, Cozzi L. A broad scope knowledge based model for optimization of VMAT in esophageal cancer: validation and assessment of plan quality among different treatment centers. Radiat Oncol 2015; 10:220. [PMID: 26521015 PMCID: PMC4628288 DOI: 10.1186/s13014-015-0530-5] [Citation(s) in RCA: 77] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2015] [Accepted: 10/26/2015] [Indexed: 01/26/2023] Open
Abstract
BACKGROUND To evaluate the performance of a broad scope model-based optimisation process for volumetric modulated arc therapy applied to esophageal cancer. METHODS AND MATERIALS A set of 70 previously treated patients in two different institutions, were selected to train a model for the prediction of dose-volume constraints. The model was built with a broad-scope purpose, aiming to be effective for different dose prescriptions and tumour localisations. It was validated on three groups of patients from the same institution and from another clinic not providing patients for the training phase. Comparison of the automated plans was done against reference cases given by the clinically accepted plans. RESULTS Quantitative improvements (statistically significant for the majority of the analysed dose-volume parameters) were observed between the benchmark and the test plans. Of 624 dose-volume objectives assessed for plan evaluation, in 21 cases (3.3 %) the reference plans failed to respect the constraints while the model-based plans succeeded. Only in 3 cases (<0.5 %) the reference plans passed the criteria while the model-based failed. In 5.3 % of the cases both groups of plans failed and in the remaining cases both passed the tests. CONCLUSIONS Plans were optimised using a broad scope knowledge-based model to determine the dose-volume constraints. The results showed dosimetric improvements when compared to the benchmark data. Particularly the plans optimised for patients from the third centre, not participating to the training, resulted in superior quality. The data suggests that the new engine is reliable and could encourage its application to clinical practice.
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Affiliation(s)
- Antonella Fogliata
- Radiotherapy and Radiosurgery Department, Humanitas Clinical and Research Center, Milan-Rozzano, Italy
| | - Giorgia Nicolini
- Oncology Institute of Southern Switzerland, Bellinzona, Switzerland
| | | | - Eugenio Vanetti
- Oncology Institute of Southern Switzerland, Bellinzona, Switzerland
| | - Sarbani Laksar
- Radiotherapy Department, Tata Memorial Hospital, Mumbai, India
| | - Angelo Tozzi
- Radiotherapy and Radiosurgery Department, Humanitas Clinical and Research Center, Milan-Rozzano, Italy
| | - Marta Scorsetti
- Radiotherapy and Radiosurgery Department, Humanitas Clinical and Research Center, Milan-Rozzano, Italy
| | - Luca Cozzi
- Radiotherapy and Radiosurgery Department, Humanitas Clinical and Research Center, Milan-Rozzano, Italy.
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An IMRT/VMAT Technique for Nonsmall Cell Lung Cancer. BIOMED RESEARCH INTERNATIONAL 2015; 2015:613060. [PMID: 26539515 PMCID: PMC4619809 DOI: 10.1155/2015/613060] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/09/2015] [Revised: 07/13/2015] [Accepted: 07/21/2015] [Indexed: 01/22/2023]
Abstract
The study is to investigate a Hybrid IMRT/VMAT technique which combines intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT) for the treatment of nonsmall cell lung cancer (NSCLC). Two partial arcs VMAT, 5-field IMRT, and hybrid plans were created for 15 patients with NSCLC. The hybrid plans were combination of 2 partial arcs VMAT and 5-field IMRT. The dose distribution of planning target volume (PTV) and organs at risk (OARs) for hybrid technique was compared with IMRT and VMAT. The monitor units (MUs) and treatment delivery time were also evaluated. Hybrid technique significantly improved the target conformity and homogeneity compared with IMRT and VMAT. The mean delivery time of IMRT, VMAT, and hybrid plans was 280 s, 114 s, and 327 s, respectively. The mean MUs needed for IMRT, VMAT, and hybrid plans were 933, 512, and 737, respectively. Hybrid technique reduced V5, V10, V30, and MLD of normal lung compared with VMAT and spared the OARs better with fewer MUs with the cost of a little higher V5, V10, and mean lung dose (MLD) of normal lung compared with IMRT. Hybrid IMRT/VMAT can be a viable radiotherapy technique with better plan quality.
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20
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Duma MN, Berndt J, Rondak IC, Devecka M, Wilkens JJ, Geinitz H, Combs SE, Oechsner M. Implications of free breathing motion assessed by 4D-computed tomography on the delivered dose in radiotherapy for esophageal cancer. Med Dosim 2015; 40:378-82. [PMID: 26419857 DOI: 10.1016/j.meddos.2015.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Revised: 07/03/2015] [Accepted: 07/29/2015] [Indexed: 12/25/2022]
Abstract
The aim of this study was to assess the effect of breathing motion on the delivered dose in esophageal cancer 3-dimensional (3D)-conformal radiotherapy (3D-CRT), intensity-modulated radiotherapy (IMRT), and volumetric modulated arc therapy (VMAT). We assessed 16 patients with esophageal cancer. All patients underwent 4D-computed tomography (4D-CT) for treatment planning. For each of the analyzed patients, 1 3D-CRT, 1 IMRT, and 1 VMAT (RapidArc-RA) plan were calculated. Each of the 3 initial plans was recalculated on the 4D-CT (for the maximum free inspiration and maximum free expiration) to assess the effect of breathing motion. We assessed the minimum dose (Dmin) and mean dose (Dmean) to the esophagus within the planning target volume, the volume changes of the lungs, the Dmean and the total lung volume receiving at least 40Gy (V40), and the V30, V20, V10, and V5. For the heart we assessed the Dmean and the V25. Over all techniques and all patients the change in Dmean as compared with the planned Dmean (planning CT [PCT]) to the esophagus was 0.48% in maximum free inspiration (CT_insp) and 0.55% in maximum free expiration (CT_exp). The Dmin CT_insp change was 0.86% and CT_exp change was 0.89%. The Dmean change of the lungs (heart) was in CT_insp 1.95% (2.89%) and 3.88% (2.38%) in CT_exp. In all, 4 patients had a clinically relevant change of the dose (≥ 5% Dmean to the heart and the lungs) between inspiration and expiration. These patients had a very cranially or caudally situated tumor. There are no relevant differences in the delivered dose to the regions of interest among the 3 techniques. Breathing motion management could be considered to achieve a better sparing of the lungs or heart in patients with cranially or caudally situated tumors.
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Affiliation(s)
- Marciana Nona Duma
- Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, München, Germany.
| | - Johannes Berndt
- Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, München, Germany
| | - Ina-Christine Rondak
- Institute of Medical Statistics and Epidemiology, Klinikum rechts der Isar, Technische Universität München, München, Germany
| | - Michal Devecka
- Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, München, Germany
| | - Jan J Wilkens
- Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, München, Germany
| | - Hans Geinitz
- Department of Radiation Oncology, Krankenhaus Barmherzige Schwestern Linz, Austria
| | - Stephanie Elisabeth Combs
- Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, München, Germany
| | - Markus Oechsner
- Department of Radiation Oncology, Klinikum rechts der Isar, Technische Universität München, München, Germany
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21
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Fan-shaped complete block on helical tomotherapy for esophageal cancer: a phantom study. BIOMED RESEARCH INTERNATIONAL 2015; 2015:959504. [PMID: 25767810 PMCID: PMC4342177 DOI: 10.1155/2015/959504] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 01/13/2015] [Accepted: 01/14/2015] [Indexed: 11/18/2022]
Abstract
Radiation pneumonitis (RP) is a common complication for radiotherapy of esophageal cancer and is associated with the low dose irradiated lung volume. This study aims to reduce the mean lung dose (MLD) and the relative lung volume at 20 Gy (V20) and at low dose region using various designs of the fan-shaped complete block (FSCB) in helical tomotherapy. Hypothetical esophageal tumor was delineated on an anthropomorphic phantom. The FSCB was defined as the fan-shaped radiation restricted area located in both lungs. Seven treatment plans were performed with nonblock design and FSCB with different fan angles, that is, from 90° to 140°, with increment of 10°. The homogeneous index, conformation number, MLD, and the relative lung volume receiving more than 5, 10, 15, and 20 Gy (V5, V10, V15, and V20) were determined for each treatment scheme. There was a substantial reduction in the MLD, V5, V10, V15, and V20 when using different types of FSCB as compared to the nonblock design. The reduction of V20, V15, V10, and V5 was 6.3%–8.6%, 16%–23%, 42%–57%, and 42%–66% for FSCB 90°–140°, respectively. The use of FSCB in helical tomotherapy is a promising method to reduce the MLD, V20, and relative lung volume in low dose region, especially in V5 and V10 for esophageal cancer.
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22
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Calais J, Dubray B, Nkhali L, Thureau S, Lemarignier C, Modzelewski R, Gardin I, Di Fiore F, Michel P, Vera P. High FDG uptake areas on pre-radiotherapy PET/CT identify preferential sites of local relapse after chemoradiotherapy for locally advanced oesophageal cancer. Eur J Nucl Med Mol Imaging 2015; 42:858-67. [PMID: 25680400 DOI: 10.1007/s00259-015-3004-y] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2014] [Accepted: 01/16/2015] [Indexed: 11/27/2022]
Abstract
PURPOSE The high failure rates in the radiotherapy (RT) target volume suggest that patients with locally advanced oesophageal cancer (LAOC) would benefit from increased total RT doses. High 2-deoxy-2-[(18)F]fluoro-D-glucose (FDG) uptake (hotspot) on pre-RT FDG positron emission tomography (PET)/CT has been reported to identify intra-tumour sites at increased risk of relapse after RT in non-small cell lung cancer and in rectal cancer. Our aim was to confirm these observations in patients with LAOC and to determine the optimal maximum standardized uptake value (SUVmax) threshold to delineate smaller RT target volumes that would facilitate RT dose escalation without impaired tolerance. METHODS The study included 98 consecutive patients with LAOC treated by chemoradiotherapy (CRT). All patients underwent FDG PET/CT at initial staging and during systematic follow-up in a single institution. FDG PET/CT acquisitions were coregistered on the initial CT scan. Various subvolumes within the initial tumour (30, 40, 50, 60, 70, 80 and 90% SUVmax thresholds) and in the subsequent local recurrence (LR, 40 and 90% SUVmax thresholds) were pasted on the initial CT scan and compared[Dice, Jaccard, overlap fraction (OF), common volume/baseline volume, common volume/recurrent volume]. RESULTS Thirty-five patients had LR. The initial metabolic tumour volume was significantly higher in LR tumours than in the locally controlled tumours (mean 25.4 vs 14.2 cc; p = 0.002). The subvolumes delineated on initial PET/CT with a 30-60% SUVmax threshold were in good agreement with the recurrent volume at 40% SUVmax (OF = 0.60-0.80). The subvolumes delineated on initial PET/CT with a 30-60% SUVmax threshold were in good to excellent agreement with the core volume (90% SUVmax) of the relapse (common volume/recurrent volume and OF indices 0.61-0.89). CONCLUSION High FDG uptake on pretreatment PET/CT identifies tumour subvolumes that are at greater risk of recurrence after CRT in patients with LAOC. We propose a 60% SUVmax threshold to delineate high FDG uptake areas on initial PET/CT as reduced target volumes for RT dose escalation.
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Affiliation(s)
- Jérémie Calais
- Nuclear Medicine Department, Henri Becquerel Cancer Center and Rouen University Hospital, Rouen, France,
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23
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Zhao Y, Chen L, Zhang S, Wu Q, Jiang X, Zhu H, Wang J, Li Z, Xu Y, Zhang YJ, Bai S, Xu F. Predictive factors for acute radiation pneumonitis in postoperative intensity modulated radiation therapy and volumetric modulated arc therapy of esophageal cancer. Thorac Cancer 2015; 6:49-57. [PMID: 26273335 PMCID: PMC4448459 DOI: 10.1111/1759-7714.12142] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2014] [Accepted: 05/16/2014] [Indexed: 02/05/2023] Open
Abstract
Background Radiation pneumonitis (RP) is a common side reaction in radiotherapy for esophageal cancer. There are few reports about RP in esophageal cancer patients receiving postoperative intensity modulated radiation therapy (IMRT) and volumetric modulated arc therapy (VMAT). This study aims to analyze clinical or dosimetric factors associated with RP, and provides data for radiotherapy planning. Methods We reviewed 68 postoperative esophageal cancer patients who were treated with radiotherapy at the West China Hospital from October 2010 to November 2012 to identify any correlation between the clinical or dosimetric parameters and acute radiation pneumonitis (ARP) or severe acute radiation pneumonitis (SARP) by t-test, chi-square test, and logistic regression analysis. Results Of the 68 patients, 33 patients (48.5%) developed ARP, 13 of which (19.1%) developed SARP. Of these 33 patients, 8 (11.8%), 12 (17.6%), 11 (16.2%), and 2 (2.9%) patients were grade 1, 2, 3, and 4 ARP, respectively. Univariate analysis showed that lung infection during radiotherapy, use of VMAT, mean lung dose (MLD), and dosimetric parameters (e.g. V20, V30) are significantly correlated with RP. Multivariate analysis found that lung infection during radiotherapy, MLD ≥ 12 Gy, and V30 ≥ 13% are significantly correlated with an increased risk of RP. Conclusion Lung infection during radiotherapy and low radiation dose volume distribution were predictive factors associated with RP and should be accounted for during radiation planning.
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Affiliation(s)
- Yaqin Zhao
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Lu Chen
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Shu Zhang
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Qiang Wu
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Xiaoqin Jiang
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Hong Zhu
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Jin Wang
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Zhiping Li
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Yong Xu
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Ying Jie Zhang
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Sen Bai
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
| | - Feng Xu
- Cancer Center, West China Hospital, Sichuan University Chengdu, China
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24
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Vieillevigne L, Vidal M, Izar F, Rives M. Is dose escalation achievable for esophageal carcinoma? Rep Pract Oncol Radiother 2015; 20:135-40. [PMID: 25859404 DOI: 10.1016/j.rpor.2014.12.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 11/14/2014] [Accepted: 12/11/2014] [Indexed: 02/07/2023] Open
Abstract
AIM To investigate the feasibility of dose escalation using rapid arc (RA) and Helical Tomotherapy (HT) for patients with upper, middle and distal esophageal carcinomas, even for large tumor volumes. BACKGROUND In esophageal cancer, for patients with exclusive radio-chemotherapy, local disease control remains poor. Planning study with dose escalation was done for two sophisticated modulated radiotherapy techniques: Rapid arc against Tomotherapy. MATERIALS AND METHODS Six patients treated with a RA simultaneous integrated boost (SIB) of 60 Gy were re-planned for RA and HT techniques with a SIB dose escalated to 70 Gy. Dose volume histogram statistics, conformity indices and homogeneity indices were analyzed. For a given set of normal tissue constraints, the capability of each treatment modality to increase the GTV dose to 70 Gy was investigated. RESULTS Either HT or VMAT may be used to escalate the dose delivered in esophageal tumors while maintaining the spinal cord, lung and heart doses within tolerance. Adequate target coverage was achieved by both techniques. Typically, HT achieved better lung sparing and PTV coverage than did RA. CONCLUSIONS Dose escalation for esophageal cancer becomes clinically feasible with the use of RA and HT. This promising result could be explored in a carefully controlled clinical study which considered normal tissue complications and tumor control as endpoints.
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Affiliation(s)
- Laure Vieillevigne
- Institut Claudius Regaud, Institut Universitaire du Cancer de Toulouse Oncopole, Radiotherapy Department, France
| | - Marie Vidal
- Institut Claudius Regaud, Institut Universitaire du Cancer de Toulouse Oncopole, Radiotherapy Department, France
| | - Françoise Izar
- Institut Claudius Regaud, Institut Universitaire du Cancer de Toulouse Oncopole, Radiotherapy Department, France
| | - Michel Rives
- Institut Claudius Regaud, Institut Universitaire du Cancer de Toulouse Oncopole, Radiotherapy Department, France
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25
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Rong Y, Chen Y, Shang L, Zuo L, Lu W, Chen Q. Helical tomotherapy with dynamic running-start-stop delivery compared to conventional tomotherapy delivery. Med Phys 2014; 41:051709. [PMID: 24784375 DOI: 10.1118/1.4870987] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE Despite superior target dose uniformity, helical tomotherapy(®) (HT) may involve a trade-off between longitudinal dose conformity and beam-on time (BOT), due to the limitation of only three available jaw sizes with the conventional HT (1.0, 2.5, and 5.0 cm). The recently introduced dynamic running-start-stop (RSS) delivery allows smaller jaw opening at the superior and inferior ends of the target when a sharp penumbra is needed. This study compared the dosimetric performance of RSS delivery with the fixed jaw HT delivery. METHODS Twenty patient cases were selected and deidentified prior to treatment planning, including 16 common clinical cases (brain, head and neck (HN), lung, and prostate) and four special cases of whole brain with hippocampus avoidance (WBHA) that require a high degree of dose modulation. HT plans were generated for common clinical cases using the fixed 2.5 cm jaw width (HT2.5) and WBHA cases using 1.0 cm (HT1.0). The jaw widths for RSS were preset with a larger size (RSS5.0 vs HT2.5 and RSS2.5 vs HT1.0). Both delivery techniques were planned based on identical contours, prescriptions, and planning objectives. Dose indices for targets and critical organs were compared using dose-volume histograms, BOT, and monitor units. RESULTS The average BOT was reduced from 4.8 min with HT2.5 to 2.5 min with RSS5.0. Target dose homogeneity with RSS5.0 was shown comparable to HT2.5 for common clinical sites. Superior normal tissue sparing was observed in RSS5.0 for optic nerves and optic chiasm in brain and HN cases. RSS5.0 demonstrated improved dose sparing for cord and esophagus in lung cases, as well as penile bulb in prostate cases. The mean body dose was comparable for both techniques. For the WBHA cases, the target homogeneity was significantly degraded in RSS2.5 without distinct dose sparing for hippocampus, compared to HT1.0. CONCLUSIONS Compared to the fixed jaw HT delivery, RSS combined with a larger jaw width provides faster treatment delivery and improved cranial-caudal target dose conformity. The target coverage achieved by RSS with a large jaw width is comparable to the fixed jaw HT delivery for common cancer sites, but may deteriorate for cases where complex geometry is present in the middle part of the target.
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Affiliation(s)
- Yi Rong
- Department of Radiation Oncology, The Ohio State University Wexner Medical Center, Columbus, Ohio 43210
| | - Yu Chen
- 21st Century Oncology, Madison, Wisconsin 53719
| | - Lu Shang
- Guangxi Polytechnic of Construction and Technology, Nanning, China
| | - Li Zuo
- Radiologic Sciences and Respiratory Therapy Division, School of Health and Rehabilitation Sciences, The Ohio State University College of Medicine, Columbus, Ohio 43210
| | - Weiguo Lu
- 21st Century Oncology, Madison, Wisconsin 53719
| | - Quan Chen
- Department of Radiation Oncology, University of Virginia, Charlottesville, Virginia 22904
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26
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Ling TC, Slater JM, Nookala P, Mifflin R, Grove R, Ly AM, Patyal B, Slater JD, Yang GY. Analysis of Intensity-Modulated Radiation Therapy (IMRT), Proton and 3D Conformal Radiotherapy (3D-CRT) for Reducing Perioperative Cardiopulmonary Complications in Esophageal Cancer Patients. Cancers (Basel) 2014; 6:2356-68. [PMID: 25489937 PMCID: PMC4276971 DOI: 10.3390/cancers6042356] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2014] [Revised: 11/20/2014] [Accepted: 12/01/2014] [Indexed: 12/25/2022] Open
Abstract
Background. While neoadjuvant concurrent chemoradiotherapy has improved outcomes for esophageal cancer patients, surgical complication rates remain high. The most frequent perioperative complications after trimodality therapy were cardiopulmonary in nature. The radiation modality utilized can be a strong mitigating factor of perioperative complications given the location of the esophagus and its proximity to the heart and lungs. The purpose of this study is to make a dosimetric comparison of Intensity-Modulated Radiation Therapy (IMRT), proton and 3D conformal radiotherapy (3D-CRT) with regard to reducing perioperative cardiopulmonary complications in esophageal cancer patients. Materials. Ten patients with esophageal cancer treated between 2010 and 2013 were evaluated in this study. All patients were simulated with contrast-enhanced CT imaging. Separate treatment plans using proton radiotherapy, IMRT, and 3D-CRT modalities were created for each patient. Dose-volume histograms were calculated and analyzed to compare plans between the three modalities. The organs at risk (OAR) being evaluated in this study are the heart, lungs, and spinal cord. To determine statistical significance, ANOVA and two-tailed paired t-tests were performed for all data parameters. Results. The proton plans showed decreased dose to various volumes of the heart and lungs in comparison to both the IMRT and 3D-CRT plans. There was no difference between the IMRT and 3D-CRT plans in dose delivered to the lung or heart. This finding was seen consistently across the parameters analyzed in this study. Conclusions. In patients receiving radiation therapy for esophageal cancer, proton plans are technically feasible while achieving adequate coverage with lower doses delivered to the lungs and cardiac structures. This may result in decreased cardiopulmonary toxicity and less morbidity to esophageal cancer patients.
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Affiliation(s)
- Ted C Ling
- Department of Radiation Medicine, Loma Linda University Medical Center, 11234 Anderson Street, A875, Loma Linda, CA 92354, USA.
| | - Jerry M Slater
- Department of Radiation Medicine, Loma Linda University Medical Center, 11234 Anderson Street, A875, Loma Linda, CA 92354, USA.
| | - Prashanth Nookala
- Department of Radiation Medicine, Loma Linda University Medical Center, 11234 Anderson Street, A875, Loma Linda, CA 92354, USA.
| | - Rachel Mifflin
- Department of Radiation Medicine, Loma Linda University Medical Center, 11234 Anderson Street, A875, Loma Linda, CA 92354, USA.
| | - Roger Grove
- Department of Radiation Medicine, Loma Linda University Medical Center, 11234 Anderson Street, A875, Loma Linda, CA 92354, USA.
| | - Anh M Ly
- Department of Radiation Medicine, Loma Linda University Medical Center, 11234 Anderson Street, A875, Loma Linda, CA 92354, USA.
| | - Baldev Patyal
- Department of Radiation Medicine, Loma Linda University Medical Center, 11234 Anderson Street, A875, Loma Linda, CA 92354, USA.
| | - Jerry D Slater
- Department of Radiation Medicine, Loma Linda University Medical Center, 11234 Anderson Street, A875, Loma Linda, CA 92354, USA.
| | - Gary Y Yang
- Department of Radiation Medicine, Loma Linda University Medical Center, 11234 Anderson Street, A875, Loma Linda, CA 92354, USA.
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Warren S, Partridge M, Carrington R, Hurt C, Crosby T, Hawkins MA. Radiobiological determination of dose escalation and normal tissue toxicity in definitive chemoradiation therapy for esophageal cancer. Int J Radiat Oncol Biol Phys 2014; 90:423-9. [PMID: 25304796 PMCID: PMC4165721 DOI: 10.1016/j.ijrobp.2014.06.028] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 06/04/2014] [Accepted: 06/06/2014] [Indexed: 12/25/2022]
Abstract
PURPOSE This study investigated the trade-off in tumor coverage and organ-at-risk sparing when applying dose escalation for concurrent chemoradiation therapy (CRT) of mid-esophageal cancer, using radiobiological modeling to estimate local control and normal tissue toxicity. METHODS AND MATERIALS Twenty-one patients with mid-esophageal cancer were selected from the SCOPE1 database (International Standard Randomised Controlled Trials number 47718479), with a mean planning target volume (PTV) of 327 cm(3). A boost volume, PTV2 (GTV + 0.5 cm margin), was created. Radiobiological modeling of tumor control probability (TCP) estimated the dose required for a clinically significant (+20%) increase in local control as 62.5 Gy/25 fractions. A RapidArc (RA) plan with a simultaneously integrated boost (SIB) to PTV2 (RA62.5) was compared to a standard dose plan of 50 Gy/25 fractions (RA50). Dose-volume metrics and estimates of normal tissue complication probability (NTCP) for heart and lungs were compared. RESULTS Clinically acceptable dose escalation was feasible for 16 of 21 patients, with significant gains (>18%) in tumor control from 38.2% (RA50) to 56.3% (RA62.5), and only a small increase in predicted toxicity: median heart NTCP 4.4% (RA50) versus 5.6% (RA62.5) P<.001 and median lung NTCP 6.5% (RA50) versus 7.5% (RA62.5) P<.001. CONCLUSIONS Dose escalation to the GTV to improve local control is possible when overlap between PTV and organ-at-risk (<8% heart volume and <2.5% lung volume overlap for this study) generates only negligible increase in lung or heart toxicity. These predictions from radiobiological modeling should be tested in future clinical trials.
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Affiliation(s)
- Samantha Warren
- Department of Oncology, Gray Institute of Radiation Oncology and Biology, University of Oxford, Oxford, United Kingdom.
| | - Mike Partridge
- Department of Oncology, Gray Institute of Radiation Oncology and Biology, University of Oxford, Oxford, United Kingdom
| | - Rhys Carrington
- Velindre Cancer Centre, Velindre Hospital, Cardiff, United Kingdom
| | - Chris Hurt
- Wales Cancer Trials Unit, School of Medicine, Heath Park, Cardiff, United Kingdom
| | - Thomas Crosby
- Velindre Cancer Centre, Velindre Hospital, Cardiff, United Kingdom
| | - Maria A Hawkins
- Department of Oncology, Gray Institute of Radiation Oncology and Biology, University of Oxford, Oxford, United Kingdom
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28
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Lin CY, Huang WY, Jen YM, Chen CM, Su YF, Chao HL, Lin CS. Dosimetric and efficiency comparison of high-dose radiotherapy for esophageal cancer: volumetric modulated arc therapy versus fixed-field intensity-modulated radiotherapy. Dis Esophagus 2014; 27:585-90. [PMID: 24134466 DOI: 10.1111/dote.12144] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The aim of this study was to compare high-dose volumetric modulated arc therapy (VMAT) and fixed-field intensity-modulated radiotherapy (ff-IMRT) plans for the treatment of patients with middle-thoracic esophageal cancer. Eight patients with cT2-3N0M0 middle-thoracic esophageal cancer were enrolled. The treatment planning system was the version 9 of the Pinnacle(3) with SmartArc (Philips Healthcare, Fitchburg, WI, USA). VMAT and ff-IMRT treatment plans were generated for each case, and both techniques were used to deliver 50 Gy to the planning target volume (PTV(50)) and then provided a 16-Gy boost (PTV(66)). The VMAT plans provided superior PTV(66) coverage compared with the ff-IMRT plans (P = 0.034), whereas the ff-IMRT plans provided more appropriate dose homogeneity to the PTV(50) (P = 0.017). In the lung, the V(5) and V(10) were lower for the ff-IMRT plans than for the VMAT plans, whereas the V(20) was lower for the VMAT plans. The delivery time was significantly shorter for the VMAT plans than for the ff-IMRT plans (P = 0.012). In addition, the VMAT plans delivered fewer monitor units. The VMAT technique required a shorter planning time than the ff-IMRT technique (3.8 ± 0.8 hours vs. 5.4 ± 0.6 hours, P = 0.011). The major advantages of VMAT plans are higher efficiency and an approximately 50% reduction in delivery time compared with the ff-IMRT plans, with comparable plan quality. Further clinical investigations to evaluate the use of high-dose VMAT for the treatment of esophageal cancer are warranted.
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Affiliation(s)
- C-Y Lin
- Department of Radiation Oncology, Chang Gung Memorial Hospital-Linkou, Chang Gung University, Taoyuan, Taiwan; Department of Radiation Oncology, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan
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29
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Yoon HI, Lee IJ, Han KH, Seong J. Improved oncologic outcomes with image-guided intensity-modulated radiation therapy using helical tomotherapy in locally advanced hepatocellular carcinoma. J Cancer Res Clin Oncol 2014; 140:1595-605. [PMID: 24809934 DOI: 10.1007/s00432-014-1697-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 04/24/2014] [Indexed: 01/12/2023]
Abstract
AIM To investigate whether image-guided intensity-modulated radiation therapy (IG-IMRT) improves survival in hepatocellular carcinoma (HCC) relative to 3-dimensional conformal radiotherapy (3D-CRT). METHODS Between 2006 and 2011, 187 HCC patients treated with definitive RT were reviewed. Median age was 53(range 51-83). All patients were stage III or IV-A. Concurrent chemoradiation was received by 178 patients (95.2 %). Overall actuarial survival (OS), progression-free survival (PFS), and infield-failure-free survival (IFFS) analyses were performed by Kaplan-Meier method. A Cox proportional hazards model was used for univariate and multivariate analysis. Pearson's chi-square test or Fisher's exact test was used to compare patient characteristics and treatment-related toxicity between the groups. RESULTS Sixty-five patients were treated with IG-IMRT and 122 patients with 3D-CRT. No significant differences were seen between the groups for all patient characteristics. IG-IMRT delivered higher doses than 3D-CRT (median biological effective dose 62.5 vs 53.1 Gy, P < 0.001). IG-IMRT showed significantly higher 3-year OS (33.4 vs 13.5 %, P < 0.001), PFS (11.1 vs 6.0 %, P = 0.004), and IFFS (46.8 vs 28.2 %, P = 0.007) than 3D-CRT. On univariate and multivariate analysis, RT modality was significant prognostic factor for OS (HR 2.18; 95 % CI 1.45-3.25; P < 0.001), PFS (HR 1.64; 95 % CI 1.17-2.29; P = 0.004). There was no significant difference between the two modalities for radiation-induced liver disease (P = 0.716). CONCLUSION Our findings suggest that IG-IMRT could be an effective treatment that provides survival benefit without increasing severe toxicity in locally advanced HCC.
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Affiliation(s)
- Hong In Yoon
- Department of Radiation Oncology, Yonsei Cancer Center, Yonsei University Health System, Yonsei University College of Medicine, 50-1 Yonsei-ro, Seodaemun-gu, Seoul, 120-752, Republic of Korea
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Wu Z, Xie C, Hu M, Han C, Yi J, Zhou Y, Yuan H, Jin X. Dosimetric benefits of IMRT and VMAT in the treatment of middle thoracic esophageal cancer: is the conformal radiotherapy still an alternative option? J Appl Clin Med Phys 2014; 15:93–101. [PMID: 24892336 PMCID: PMC5711052 DOI: 10.1120/jacmp.v15i3.4641] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2013] [Revised: 09/25/2013] [Accepted: 12/06/2013] [Indexed: 11/23/2022] Open
Abstract
The purpose of this study is to investigate the dosimetric differences among conformal radiotherapy (CRT), intensity-modulated radiotherapy (IMRT), and volumetric-modulated radiotherapy (VMAT) in the treatment of middle thoracic esophageal cancer, and determine the most appropriate treatment modality. IMRT and one-arc VMAT plans were generated for eight middle thoracic esophageal cancer patients treated previous with CRT. The planning target volume (PTV) coverage and protections on organs at risk of three planning schemes were compared. All plans have sufficient PTV coverage and no significant differences were observed, except for the conformity and homogeneity. The lung V5, V10, and V13 in CRT were 47.9% ± 6.1%, 36.5% ± 4.6%, and 33.2% ± 4.2%, respectively, which were greatly increased to 78.2% ± 13.7% (p < 0.01), 80.8% ± 14.9% (p < 0.01), 48.4% ± 8.2% (p = 0.05) in IMRT and 58.6% ± 10.5% (p = 0.03), 67.7% ± 14.0% (p < 0.01), and 53.0% ± 10.1% (p < 0.01) in VMAT, respectively. The lung V20 (p = 0.03) in VMAT and the V30 (p = 0.04) in IMRT were lower than those in CRT. Both IMRT and VMAT achieved a better protection on heart. However, the volumes of the healthy tissue outside of PTV irradiated by a low dose were higher for IMRT and VMAT. IMRT and VMAT also had a higher MU, optimization time, and delivery time compared to CRT. In conclusion, all CRT, IMRT, and VMAT plans are able to meet the prescription and there is no clear distinction on PTV coverage. IMRT and VMAT can only decrease the volume of lung and heart receiving a high dose, but at a cost of delivering low dose to more volume of lung and normal tissues. CRT is still a feasible option for middle thoracic esophageal cancer radiotherapy, especially for the cost-effective consideration.
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Affiliation(s)
- Zhiqin Wu
- the 1st Affiliated Hospital of Wenzhou Medical College.
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Ma P, Wang X, Xu Y, Dai J, Wang L. Applying the technique of volume-modulated arc radiotherapy to upper esophageal carcinoma. J Appl Clin Med Phys 2014; 15:4732. [PMID: 24892348 PMCID: PMC5711044 DOI: 10.1120/jacmp.v15i3.4732] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2013] [Revised: 02/07/2014] [Accepted: 01/31/2014] [Indexed: 11/23/2022] Open
Abstract
This study aims to evaluate the possibility of using the technique of volume-modulated arc therapy (VMAT) to combine the advantages of simplified intensity-modulated radiation therapy (sIMRT) with that of regular intensity-modulated radiation therapy (IMRT) in upper esophageal cancer. Ten patients with upper esophageal carcinoma were randomly chosen in this retrospective study. sIMRT, IMRT, and VMAT plans were generated to deliver 60 Gy in 30 fractions to the planning target volume (PTV). For each patient, with the same clinical requirements (target dose prescription, and dose/dose-volume constraints to organs at risk (OARs)), three plans were designed for sIMRT (five equispaced coplanar beams), IMRT (seven equispaced coplanar beams), and VMAT (two complete arcs). Comparisons were performed for dosimetric parameters of PTV and of OARs (lungs, spinal cord PRV, heart and normal tissue (NT)). All the plans were delivered to a phantom to evaluate the treatment time. The Wilcoxon matched-pairs, signed-rank test was used for intragroup comparison. For all patients, compared to sIMRT plans, VMAT plans statistically provide: a) significant improvement in HI and CI for PTV; b) significant decrease in delivery time, lung V20, MLD, heart V30 and spinal cord PRV D1cc; c) significant increase in NT V5; and d) no significant reduction in lung V5, V10, and heart MD. For all patients, compared to IMRT plans, VMAT plans statistically provide: a) significant improvement in CI for PTV; b) significant decrease in delivery time, lung V20, MLD, NT and spinal cord PRV D1cc; c) significant increase in NT V5; and d) no significant reduction in HI for PTV, lung V5, V10, heart V30 and heart MD. For patients with upper esophageal carcinoma, using VMAT significantly reduces the delivery time and the dose to the lungs compared with IMRT, and consequently saves as much treatment time as sIMRT. Considering those significant advantages, compared to sIMRT and IMRT, VMAT is the first choice of radiotherapy techniques for upper esophageal carcinoma.
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Affiliation(s)
- Pan Ma
- Chinese Academy of Medical Sciences.
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Matuszak MM, Steers JM, Long T, McShan DL, Fraass BA, Romeijn HE, Ten Haken RK. FusionArc optimization: a hybrid volumetric modulated arc therapy (VMAT) and intensity modulated radiation therapy (IMRT) planning strategy. Med Phys 2014; 40:071713. [PMID: 23822417 DOI: 10.1118/1.4808153] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To introduce a hybrid volumetric modulated arc therapy/intensity modulated radiation therapy (VMAT/IMRT) optimization strategy called FusionArc that combines the delivery efficiency of single-arc VMAT with the potentially desirable intensity modulation possible with IMRT. METHODS A beamlet-based inverse planning system was enhanced to combine the advantages of VMAT and IMRT into one comprehensive technique. In the hybrid strategy, baseline single-arc VMAT plans are optimized and then the current cost function gradients with respect to the beamlets are used to define a metric for predicting which beam angles would benefit from further intensity modulation. Beams with the highest metric values (called the gradient factor) are converted from VMAT apertures to IMRT fluence, and the optimization proceeds with the mixed variable set until convergence or until additional beams are selected for conversion. One phantom and two clinical cases were used to validate the gradient factor and characterize the FusionArc strategy. Comparisons were made between standard IMRT, single-arc VMAT, and FusionArc plans with one to five IMRT∕hybrid beams. RESULTS The gradient factor was found to be highly predictive of the VMAT angles that would benefit plan quality the most from beam modulation. Over the three cases studied, a FusionArc plan with three converted beams achieved superior dosimetric quality with reductions in final cost ranging from 26.4% to 48.1% compared to single-arc VMAT. Additionally, the three beam FusionArc plans required 22.4%-43.7% fewer MU∕Gy than a seven beam IMRT plan. While the FusionArc plans with five converted beams offer larger reductions in final cost--32.9%-55.2% compared to single-arc VMAT--the decrease in MU∕Gy compared to IMRT was noticeably smaller at 12.2%-18.5%, when compared to IMRT. CONCLUSIONS A hybrid VMAT∕IMRT strategy was implemented to find a high quality compromise between gantry-angle and intensity-based degrees of freedom. This optimization method will allow patients to be simultaneously planned for dosimetric quality and delivery efficiency without switching between delivery techniques. Example phantom and clinical cases suggest that the conversion of only three VMAT segments to modulated beams may result in a good combination of quality and efficiency.
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Affiliation(s)
- Martha M Matuszak
- Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109, USA.
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Gong G, Wang R, Guo Y, Zhai D, Liu T, Lu J, Chen J, Liu C, Yin Y. Reduced lung dose during radiotherapy for thoracic esophageal carcinoma: VMAT combined with active breathing control for moderate DIBH. Radiat Oncol 2013; 8:291. [PMID: 24359800 PMCID: PMC3896728 DOI: 10.1186/1748-717x-8-291] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2013] [Accepted: 12/08/2013] [Indexed: 12/11/2022] Open
Abstract
Background Lung radiation injury is a critical complication of radiotherapy (RT) for thoracic esophageal carcinoma (EC). Therefore, the goal of this study was to investigate the feasibility and dosimetric effects of reducing the lung tissue irradiation dose during RT for thoracic EC by applying volumetric modulated arc radiotherapy (VMAT) combined with active breathing control (ABC) for moderate deep inspiration breath-hold (mDIBH). Methods Fifteen patients with thoracic EC were randomly selected to undergo two series of computed tomography (CT) simulation scans with ABC used to achieve mDIBH (representing 80% of peak DIBH value) versus free breathing (FB). Gross tumor volumes were contoured on different CT images, and planning target volumes (PTVs) were obtained using different margins. For PTV-FB, intensity-modulated radiotherapy (IMRT) was designed with seven fields, and VMAT included two whole arcs. For PTV-DIBH, VMAT with three 135° arcs was applied, and the corresponding plans were named: IMRT-FB, VMAT-FB, and VMAT-DIBH, respectively. Dosimetric differences between the different plans were compared. Results The heart volumes decreased by 19.85%, while total lung volume increased by 52.54% in mDIBH, compared to FB (p < 0.05). The mean conformality index values and homogeneity index values for VMAT-DIBH (0.86, 1.07) were slightly worse than those for IMRT-FB (0.90, 1.05) and VMAT-FB (0.90, 1.06) (p > 0.05). Furthermore, compared to IMRT-FB and VMAT-FB, VMAT-DIBH reduced the mean total lung dose by 18.64% and 17.84%, respectively (p < 0.05); moreover, the V5, V10, V20, and V30 values for IMRT-FB and VMAT-FB were reduced by 10.84% and 10.65% (p > 0.05), 12.5% and 20% (p < 0.05), 30.77% and 33.33% (p < 0.05), and 50.33% and 49.15% (p < 0.05), respectively. However, the heart dose-volume indices were similar between VMAT-DIBH and VMAT-FB which were lower than IMRT-FB without being statistically significant (p > 0.05). The monitor units and treatment time of VMAT-DIBH were also the lowest (p < 0.05). Conclusions VMAT combined with ABC to achieve mDIBH is a feasible approach for RT of thoracic EC. Furthermore, this method has the potential to effectively reduce lung dose in a shorter treatment time and with better targeting accuracy.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Yong Yin
- Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Jinan 250117, China.
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Wang YC, Chen SW, Chien CR, Hsieh TC, Yu CY, Kuo YC, Yang SN, Kao CH, Liang JA. Radiotherapy for esophageal cancer using simultaneous integrated boost techniques: dosimetric comparison of helical TomoTherapy, Volumetric-modulated Arc Therapy (RapidArc) and dynamic intensity-modulated radiotherapy. Technol Cancer Res Treat 2013; 12:485-91. [PMID: 23745789 DOI: 10.7785/tcrt.2012.500348] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
This study compared TomoTherapy (TM), with Volumetric-Modulated Arc Therapy (RapidArc, RA), and dynamic intensity-modulated radiotherapy (dIMRT) for locally advanced esophageal cancer (LAEC) with a simultaneous integrated boost (SIB) technique with regard to the target coverage and sparing of organs at risk (OARs). Twelve patients receiving four-dimensional computed tomography simulation were enrolled for dosimetric comparison. Gross tumor volume was contoured with the maximum intensity projection method. Using an SIB method, Planning target volume low (PTVL) and planning target volume high (PTVH) were prescribed as 54 Gy and 60 Gy, respectively, each administered in 30 fractions. We compared the results of statistical analysis for target coverage, homogeneity index (HI) and conformity index (CI) of PTVs, parameters of OARs and monitor unit (MU) were compared for analysis. The HI for PTVH varied significantly for the 3 techniques of TM, RA, and dIMRT (4.38 ± 0.86, 6.40 ± 0.86, and 6.11 ± 0.68, respectively; P , 0.001). The CI scores for PTVH also differed across TM, RA, and dIMRT (0.64 6 0.06, 0.53 6 0.06, and 0.59 ± 0.05, respectively; P < 0.001). The HI for PTVL showed a significant difference among TM, RA, and dIMRT (15.44 ± 0.88, 20.88 ± 1.03 and 18.65 ± 1.42, respectively; P < 0.001). The percentage of lung volume receiving 5 Gy (V5) and 20 Gy (V20) (for V5: TM 54.4 ± 8.0%; RA 67.5 ± 14.5%, P < 0.01; dIMRT 44.8 ± 8.2%; for V20: 13.6 6 3.3%, 12.2 ± 3.6%, 18.1 6 3.4%, P = 0.001, respectively). For RA, the lung V5 ≥ 65% was observed in 6 patients and the V10 ≥ 50 % in one patient. TM, RA and dIMRT provided comparable coverage of the target and sparing of OARs. TM demonstrated superior CI and HI for tumor coverage and lowered the specified dose parameters for lung. RA provided an advantage in terms of the lowest MU and V20 of the lung, but its higher lung V5 was of some concern about lung toxicity.
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Affiliation(s)
- Yao-Ching Wang
- Department of Radiation Oncology, China Medical University Hospital, Taichung, Taiwan.
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Abbas AS, Moseley D, Kassam Z, Kim SM, Cho C. Volumetric-modulated arc therapy for the treatment of a large planning target volume in thoracic esophageal cancer. J Appl Clin Med Phys 2013; 14:4269. [PMID: 23652258 PMCID: PMC5714417 DOI: 10.1120/jacmp.v14i3.4269] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2012] [Revised: 01/28/2013] [Accepted: 01/24/2013] [Indexed: 11/23/2022] Open
Abstract
Recently, volumetric‐modulated arc therapy (VMAT) has demonstrated the ability to deliver radiation dose precisely and accurately with a shorter delivery time compared to conventional intensity‐modulated fixed‐field treatment (IMRT). We applied the hypothesis of VMAT technique for the treatment of thoracic esophageal carcinoma to determine superior or equivalent conformal dose coverage for a large thoracic esophageal planning target volume (PTV) with superior or equivalent sparing of organs‐at‐risk (OARs) doses, and reduce delivery time and monitor units (MUs), in comparison with conventional fixed‐field IMRT plans. We also analyzed and compared some other important metrics of treatment planning and treatment delivery for both IMRT and VMAT techniques. These metrics include: 1) the integral dose and the volume receiving intermediate dose levels between IMRT and VMATI plans; 2) the use of 4D CT to determine the internal motion margin; and 3) evaluating the dosimetry of every plan through patient‐specific QA. These factors may impact the overall treatment plan quality and outcomes from the individual planning technique used. In this study, we also examined the significance of using two arcs vs. a single‐arc VMAT technique for PTV coverage, OARs doses, monitor units and delivery time. Thirteen patients, stage T2‐T3 N0‐N1 (TNM AJCC 7th edn.), PTV volume median 395 cc (range 281–601 cc), median age 69 years (range 53 to 85), were treated from July 2010 to June 2011 with a four‐field (n=4) or five‐field (n=9) step‐and‐shoot IMRT technique using a 6 MV beam to a prescribed dose of 50 Gy in 20 to 25 F. These patients were retrospectively replanned using single arc (VMATI, 91 control points) and two arcs (VMATII, 182 control points). All treatment plans of the 13 study cases were evaluated using various dose‐volume metrics. These included PTV D99, PTV D95, PTV V9547.5Gy(95%), PTV mean dose, Dmax, PTV dose conformity (Van't Riet conformation number (CN)), mean lung dose, lung V20 and V5, liver V30, and Dmax to the spinal canal prv3mm. Also examined were the total plan monitor units (MUs) and the beam delivery time. Equivalent target coverage was observed with both VMAT single and two‐arc plans. The comparison of VMATI with fixed‐field IMRT demonstrated equivalent target coverage; statistically no significant difference were found in PTV D99 (p=0.47), PTV mean (p=0.12), PTV D95 and PTV V9547.5Gy (95%) (p=0.38). However, Dmax in VMATI plans was significantly lower compared to IMRT (p=0.02). The Van't Riet dose conformation number (CN) was also statistically in favor of VMATI plans (p=0.04). VMATI achieved lower lung V20 (p=0.05), whereas lung V5 (p=0.35) and mean lung dose (p=0.62) were not significantly different. The other OARs, including spinal canal, liver, heart, and kidneys showed no statistically significant differences between the two techniques. Treatment time delivery for VMATI plans was reduced by up to 55% (p=5.8E−10) and MUs reduced by up to 16% (p=0.001). Integral dose was not statistically different between the two planning techniques (p=0.99). There were no statistically significant differences found in dose distribution of the two VMAT techniques (VMATI vs. VMATII) Dose statistics for both VMAT techniques were: PTV D99 (p=0.76), PTV D95 (p=0.95), mean PTV dose (p=0.78), conformation number (CN) (p=0.26), and MUs (p=0.1). However, the treatment delivery time for VMATII increased significantly by two‐fold (p=3.0E−11) compared to VMATI. VMAT‐based treatment planning is safe and deliverable for patients with thoracic esophageal cancer with similar planning goals, when compared to standard IMRT. The key benefit for VMATI was the reduction in treatment delivery time and MUs, and improvement in dose conformality. In our study, we found no significant difference in VMATII over single‐arc VMATI for PTV coverage or OARs doses. However, we observed significant increase in delivery time for VMATII compared to VMATI. PACS number: 87.53.Kn, 87.55.‐x
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Affiliation(s)
- Ahmar S Abbas
- Stronach Regional Cancer Centre, Newmarket, ON Canada.
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Shridhar R, Almhanna K, Meredith KL, Biagioli MC, Chuong MD, Cruz A, Hoffe SE. Radiation Therapy and Esophageal Cancer. Cancer Control 2013; 20:97-110. [DOI: 10.1177/107327481302000203] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
Abstract
Background Squamous cell carcinoma and adenocarcinoma account for more than 90% of all esophageal cancer cases. Although the incidence of squamous cell carcinoma has declined, the incidence of adenocarcinoma has risen due to increases in obesity and gastroesophageal reflux disease. Methods The authors examine the role of radiation therapy alone (external beam and brachytherapy) for the management of esophageal cancer or combined with other modalities. The impact on staging and appropriate stratification of patients referred for curative vs palliative intent with modalities is reviewed. The authors also explore the role of emerging radiation technologies. Results Current data show that neoadjuvant chemoradiotherapy followed by surgical resection is the accepted standard of care, with 3-year overall survival rates ranging from 30% to 60%. The benefit of adjuvant radiation therapy is limited to patients with node-positive cancer. The survival benefit of surgical resection after chemoradiotherapy remains controversial. External beam radiation therapy alone results in few long-term survivors and is considered palliative at best. Radiation dose-escalation has failed to improve local control or survival. Brachytherapy can provide better long-term palliation of dysphagia than metal stent placement. Although three-dimensional conformal treatment planning is the accepted standard, the roles of IMRT and proton therapy are evolving and potentially reduce adverse events due to better sparing of normal tissue. Conclusions Future directions will evaluate the benefit of induction chemotherapy followed by chemoradiotherapy, the role of surgery in locally advanced disease, and the identification of responders prior to treatment based on microarray analysis.
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Affiliation(s)
- Ravi Shridhar
- H. Lee Moffitt Cancer Center & Research Institute, Tampa, Florida
| | | | | | | | | | - Alex Cruz
- H. Lee Moffitt Cancer Center & Research Institute, Tampa, Florida
| | - Sarah E. Hoffe
- H. Lee Moffitt Cancer Center & Research Institute, Tampa, Florida
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Pardo-Montero J, Fenwick JD. Tomotherapy-like versus VMAT-like treatments: a multicriteria comparison for a prostate geometry. Med Phys 2013; 39:7418-29. [PMID: 23231292 DOI: 10.1118/1.4768159] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
PURPOSE To perform a methodological comparison of volumetric modulated arc therapy (VMAT)-like and tomotherapy-like techniques for a prostate geometry, exploring the dependence on machine, delivery, and optimization parameters of cost function values optimized for each technique. METHODS A gradient-descent algorithm is used to optimize tomotherapy-like treatments, while VMAT-like optimization is carried out using a direct-aperture simulated annealing algorithm with 180 control points equispaced at 2° angles. Dose distributions are linked to fluences via a three-dimensional double-gaussian pencil beam model. Plans are optimized for a prostate geometry, outlined according to the CHHiP protocol. The cost function used for optimization contains ten simple functions, each of which describes a single planning objective. These functions are split into three structure groups according to whether they are used to control PTV, rectal or bladder dose levels. Different optimizations have been performed by varying the relative weights of each of these structure groups, exploring in this way a three-dimensional Pareto front. Plan quality is studied according to the value of the optimized cost function and the relative Euclidean distance between the components of the cost function and those of the nearest plan lying on a reference Pareto front obtained for tomotherapy-like plans generated using a 1 cm fan-beam width and 1/3 pitch. RESULTS The quality of tomotherapy-like optimization depends on the fan-beam width, s, and rotation pitch, p, used to deliver the treatment. These values together define the effective longitudinal resolution with which fluence can be modulated, and lower cost function values are obtained for treatments optimized with tighter pitches and narrower fan-beam widths (higher modulation resolution). On the other hand, the cost function values of VMAT-like optimizations depends on the optimization running time, leaf displacement constraints, and number of arcs employed, as well as on the size of the beamlets used in the optimization (a change in leaf width from 5 to 10 mm clearly worsens the value of the objective function, but only a marginal improvement is observed when the leaf movement discretization step is reduced from 5 to 5/3 mm). However, for no combination of these parameter values did VMAT-like optimizations match the cost function values of optimized tomo-like plans obtained for s = 1 cm and p = 1∕3 (or 1/2). This is the case all across the Pareto front. On the other hand, cost function values of VMAT-like plans are generally lower than those of optimized tomotherapy-like plans obtained for s = 2.5 cm. CONCLUSIONS Tomotherapy-like plans created for the prostate geometry using a 1 cm fan-beam width and pitches of 1/3 or 1/2 have lower cost function values than VMAT-like plans, although the associated dosimetric improvements are quite small, both techniques generating very good dose distributions. When a 2.5 cm wide fan-beam is used for tomotherapy-like treatments the pattern is reversed, the tomotherapy-like plans having higher cost functions than the VMAT-like ones.
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Affiliation(s)
- Juan Pardo-Montero
- Departamento de Física de Partículas, Universidade de Santiago de Compostela, Santiago de Compostela, Spain.
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Radiotherapy and chemotherapy are associated with improved outcomes over surgery and chemotherapy in the management of limited-stage small cell esophageal carcinoma. Radiother Oncol 2013; 106:317-22. [DOI: 10.1016/j.radonc.2013.01.008] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2012] [Revised: 01/20/2013] [Accepted: 01/27/2013] [Indexed: 01/30/2023]
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Abstract
This article reviews the current management of esophageal cancer, including staging and treatment options, as well as providing support for using multidisciplinary teams to better manage esophageal cancer patients.
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Buergy D, Lohr F, Baack T, Siebenlist K, Haneder S, Michaely H, Wenz F, Boda-Heggemann J. Radiotherapy for tumors of the stomach and gastroesophageal junction--a review of its role in multimodal therapy. Radiat Oncol 2012; 7:192. [PMID: 23157945 PMCID: PMC3551733 DOI: 10.1186/1748-717x-7-192] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2012] [Accepted: 10/26/2012] [Indexed: 12/14/2022] Open
Abstract
There is broad consensus on surgical resection being the backbone of curative therapy of gastric- and gastroesophageal junction carcinoma. Nevertheless, details on therapeutic approaches in addition to surgery, such as chemotherapy, radiotherapy or radiochemotherapy are discussed controversially; especially whether external beam radiotherapy should be applied in addition to chemotherapy and surgery is debated in both entities and differs widely between regions and centers. Early landmark trials such as the Intergroup-0116 and the MAGIC trial must be interpreted in the context of potentially insufficient lymph node resection. Despite shortcomings of both trials, benefits on overall survival by radiochemotherapy and adjuvant chemotherapy were confirmed in populations of D2-resected gastric cancer patients by Asian trials. Recent results on junctional carcinoma patients strongly suggest a survival benefit of neoadjuvant radiochemotherapy in curatively resectable patients. An effect of chemotherapy in the perioperative setting as given in the MAGIC study has been confirmed by the ACCORD07 trial for junctional carcinomas; however both the studies by Stahl et al. and the excellent outcome in the CROSS trial as compared to all other therapeutic approaches indicate a superiority of neoadjuvant radiochemotherapy as compared to perioperative chemotherapy in junctional carcinoma patients. Surgery alone without neoadjuvant or perioperative therapy is considered suboptimal in patients with locally advanced disease. In gastric carcinoma patients, perioperative chemotherapy has not been compared to adjuvant radiochemotherapy in a randomized setting. Nevertheless, the results of the recently published ARTIST trial and the Chinese data by Zhu and coworkers, indicate a superiority of adjuvant radiochemotherapy as compared to adjuvant chemotherapy in terms of disease free survival in Asian patients with advanced gastric carcinoma. The ongoing CRITICS trial is supposed to provide reliable conclusions about which therapy should be preferred in Western patients with gastric carcinoma. If radiotherapy is performed, modern approaches such as intensity-modulated radiotherapy and image guidance should be applied, as these methods reduce dose to organs at risk and provide a more homogenous coverage of planning target volumes.
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Affiliation(s)
- Daniel Buergy
- Department of Radiation Oncology, Universitätsmedizin Mannheim, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
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Out-of-field contributions for IMRT and volumetric modulated arc therapy measured using gafchromic films and compared to calculations using a superposition/convolution based treatment planning system. Radiother Oncol 2012; 105:127-32. [DOI: 10.1016/j.radonc.2011.12.030] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Revised: 12/04/2011] [Accepted: 12/13/2011] [Indexed: 11/22/2022]
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Nicolini G, Ghosh-Laskar S, Shrivastava SK, Banerjee S, Chaudhary S, Agarwal JP, Munshi A, Clivio A, Fogliata A, Mancosu P, Vanetti E, Cozzi L. Volumetric Modulation Arc Radiotherapy With Flattening Filter-Free Beams Compared With Static Gantry IMRT and 3D Conformal Radiotherapy for Advanced Esophageal Cancer: A Feasibility Study. Int J Radiat Oncol Biol Phys 2012; 84:553-60. [DOI: 10.1016/j.ijrobp.2011.12.041] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2011] [Revised: 12/07/2011] [Accepted: 12/08/2011] [Indexed: 11/26/2022]
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43
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Charged particles in radiotherapy: A 5-year update of a systematic review. Radiother Oncol 2012; 103:5-7. [DOI: 10.1016/j.radonc.2012.01.003] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2012] [Accepted: 01/15/2012] [Indexed: 12/25/2022]
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