|Concomitant Imaging Dose and Cancer Risk in Image Guided Thoracic Radiation Therapy|
|Zhang, Yibao1; Wu, Hao1; Chen, Zhe2; Knisely, Jonathan P. S.3; Nath, Ravinder2; Feng, Zhongsu1; Bao, Shanglian4; Deng, Jun2|
|刊名||INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS|
|WOS标题词||Science & Technology|
|类目[WOS]||Oncology ; Radiology, Nuclear Medicine & Medical Imaging|
|研究领域[WOS]||Oncology ; Radiology, Nuclear Medicine & Medical Imaging|
|关键词[WOS]||BEAM COMPUTED-TOMOGRAPHY ; BREAST-CANCER ; CALCULATION TOOL ; HEART-DISEASE ; ABDOMINAL CT ; RADIOTHERAPY ; DOSIMETRY ; SYSTEM ; OPTIMIZATION ; VALIDATION|
Purpose: Kilovoltage cone beam computed tomography (CT) (kVCBCT) imaging guidance improves the accuracy of radiation therapy but imposes an extra radiation dose to cancer patients. This study aimed to investigate concomitant imaging dose and associated cancer risk in image guided thoracic radiation therapy.
Methods and Materials: The planning CT images and structure sets of 72 patients were converted to CT phantoms whose chest circumferences (C-chest) were calculated retrospectively. A low-dose thorax protocol on a Varian kVCBCT scanner was simulated by a validated Monte Carlo code. Computed doses to organs and cardiac substructures (for 5 selected patients of various dimensions) were regressed as empirical functions of Cchest, and associated cancer risk was calculated using the published models. The exposures to nonthoracic organs in children were also investigated.
Results: The structural mean doses decreased monotonically with increasing Cchest. For all 72 patients, the median doses to the heart, spinal cord, breasts, lungs, and involved chest were 1.68, 1.33, 1.64, 1.62, and 1.58 cGy/scan, respectively. Nonthoracic organs in children received 0.6 to 2.8 cGy/scan if they were directly irradiated. The mean doses to the descending aorta (1.43 +/- 0.68 cGy), left atrium (1.55 +/- 0.75 cGy), left ventricle (1.68 +/- 0.81 cGy), and right ventricle (1.85 +/- 0.84 cGy) were significantly different (P<.05) from the heart mean dose (1.73 +/- 0.82 cGy). The blade shielding alleviated the exposure to nonthoracic organs in children by an order of magnitude.
Conclusions: As functions of patient size, a series of models for personalized estimation of kVCBCT doses to thoracic organs and cardiac substructures have been proposed. Pediatric patients received much higher doses than did the adults, and some nonthoracic organs could be irradiated unexpectedly by the default scanning protocol. Increased cancer risks and disease adverse events in the thorax were strongly related to higher imaging doses and smaller chest dimensions. (C) 2015 Elsevier Inc. All rights reserved.
|资助机构||National Natural Science Foundation of China ; Beijing Municipal Administration of Hospitals|
|作者单位||1.Yale Univ, Dept Therapeut Radiol, New Haven, CT 06510 USA|
2.Peking Univ, Canc Hosp & Inst, Dept Radiotherapy, Key Lab Carcinogenesis & Translat Res,Minist Educ, Beijing 100871, Peoples R China
3.Hofstra North Shore LIJ Sch Med, Dept Radiat Med, Hempstead, NY USA
4.Peking Univ, Beijing Key Lab Med Phys & Engn, Beijing 100871, Peoples R China
|Zhang, Yibao,Wu, Hao,Chen, Zhe,et al. Concomitant Imaging Dose and Cancer Risk in Image Guided Thoracic Radiation Therapy[J]. INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS,2015,93(3):523-531.|
|APA||Zhang, Yibao.,Wu, Hao.,Chen, Zhe.,Knisely, Jonathan P. S..,Nath, Ravinder.,...&Deng, Jun.(2015).Concomitant Imaging Dose and Cancer Risk in Image Guided Thoracic Radiation Therapy.INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS,93(3),523-531.|
|MLA||Zhang, Yibao,et al."Concomitant Imaging Dose and Cancer Risk in Image Guided Thoracic Radiation Therapy".INTERNATIONAL JOURNAL OF RADIATION ONCOLOGY BIOLOGY PHYSICS 93.3(2015):523-531.|