• 论著 •

### 不同CT-RED校准曲线对肿瘤靶区和危及器官剂量分布的影响研究

1. 复旦大学附属肿瘤医院放疗科，复旦大学上海医学院肿瘤学系，上海 200032
• 出版日期:2021-09-30 发布日期:2021-10-08
• 通信作者: 赵　俊 E-mail: zhaojunphy@gmail.com
• 基金资助:
国家自然科学基金（11905035）。

### Effects of CT-RED calibration curves of different simulators on dose distribution of tumor target and organs at risk

YANG Yanju, ZHONG Yang, HU Weigang, GAO Dadi, ZHAO Jun

1. Department of Radiation Oncology, Fudan University Shanghai Cancer Center; Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, China
• Published:2021-09-30 Online:2021-10-08
• Contact: ZHAO Jun E-mail: zhaojunphy@gmail.com

Abstract: Background and purpose: The precise radiotherapy of tumor site depends on the precise dose distribution of the therapeutic target. The purpose of this study was to explore the influence of different computed tomography value to the relative electron density (CT-RED) calibration curve on the dose distribution of tumor and the method of fitting one CT-RED curve. Methods: Two CT scanners in Fudan University Shanghai Cancer Center were used to scan the CIRS-062 electronic density phantom, the CT- RED calibration curves of different sites (head, chest and abdomen) were obtained, and an improved CT-RED curve was optimized based on each curve. The original and modified CT-RED curves were used to calculate the dose distribution of planning target volume (PTV) (nasopharyngeal cancer, lung cancer and cervical cancer, 16 cases of each) and organ at risk (OAR) in the treatment planning system (TPS). Finally, 5 cases of each tumor were selected to verify the feasibility of optimized CT-RED. Results: The dose calculated by different CT-RED curves showed minimal differences in cervical cancer and head and neck tumor ( ＜ 1.00% and  ＜ 1.13%), but there was a large difference (2.50%) in low-density area of lung tumor. There was no significant difference ( ＜ 1.00%) between the optimized CT-RED curve and the original six CT-RED curves in the PTV and OAR. Conclusion: The corresponding CT- RED calibration curve should be selected to calculate the dose distribution of different tumors. And the improved CT-RED calibration curve scheme can also be used to reduce the potential risk of wrong calibration curve selection in the center with multiple positioning CT.