乳腺癌和鼻咽癌病人子器官剂量评估方法辅助放疗调强计划的优化

Optimization of intensity-modulated radiotherapy plan for breast cancer and nasopharyngeal carcinoma patients assisted by suborgan dose assessment method

目的本文通过拟合调强放射治疗中危及器官(organ at risk,OAR)剂量公式,探究危及器官剂量的评估方法,从而相对精准地保障调强放疗计划的质量。方法选取2017年1月至2018年12月于西南医科大学附属医院肿瘤科接受调强放疗的乳腺癌保乳术后病人(n=19)与鼻咽癌病人(n=55)的放疗计划,将OAR分割为多个子器官,子器官归一化后得到平均剂量均值,然后与各子器官到靶区表面最短距离轨迹图进行数据拟合得到相应拟合公式。结果显示不同OAR各子器官的归一化平均剂量均值与其到靶区表面最短距离呈负相关性;对上述因素进行拟合得出相应拟合公式,并评价该拟合公式取得了较好的拟合结果。结论本研究提出了一种较简便的调强放疗计划OAR剂量评估的方法,从而减少人为主观因素对OAR剂量的影响,提高调强放疗计划质量。

ObjectiveTo explore the evaluation method of organ at risk(OAR)dose in intensity modulated radiotherapy(IMRT)by fitting the dose formula of IMRT,so as to ensure the quality of IMRT plan relatively accurately.MethodsThe radiotherapy plans of breast cancer patients(nude 19)and nasopharyngeal carcinoma patients(nude 55)who received intensity modulated radiotherapy in the Oncology Department of the Affiliated Hospital of Southwest Medical University from January 2017 to December 2018were analyzed.The OAR was divided into several sub-organs,and the average dose was obtained after normalization of the sub-organs,and then the corresponding fitting formula was obtained by fitting the data with the shortest distance trajectory map of each sub-organ to the surface of the target area.ResultsThere was a negative correlation between the normalized average dose of different OAR suborgans and the shortest distance to the target surface,and the corresponding fitting formula was obtained by fitting the above factors,and a good fitting result was obtained by evaluating the fitting formula.ConclusionIn this study,we proposed a simple method to evaluate the OAR dose of intensity modulated radiotherapy planning,so as to reduce the influence of subjective factors on OAR dose and improve the quality of intensity modulated radiotherapy planning.