Comparison of rectal dose-wall histogram versus dose-volume histogram for modeling the incidence of late rectal bleeding after radiotherapy
Comparison of rectal dose-wall histogram versus dose-volume histogram for modeling the incidence of late rectal bleeding after radiotherapy
复制标题
DOI：
10.1016/j.ijrobp.2004.07.712
复制
发表时间：
2004-12-01
影响因子：
7
通讯作者：
Kuban, D
中科院分区：
文献类型：
--
作者：
Tucker, SL;Dong, L;Kuban, D
目的：为了比较正常组织并发症概率（NTCP）模型的拟合直肠剂量-壁直方图（DWH）与剂量-体积直方图（DVH）的基础上，当两者被用来分析一组常见的晚期直肠毒性data.Methods和材料：数据进行了分析，从128例前列腺癌患者与三维适形放疗（3D-CRT）在得克萨斯大学医学博士。安德森癌症中心（UTMDACC）。从治疗计划系统中获得每例患者的直肠总体积（包括内容物）的DVH。还使用直肠外轮廓加上对应于假定3 mm直肠壁厚度的自动生成的内轮廓计算DWH。分析的终点是治疗2年内2级或更高的晚期直肠出血;所有患者至少随访2年。四个不同的NTCP模型拟合的响应数据，通过使用DVH或DWH来描述剂量分布到直肠或直肠壁，分别。考虑的4个模型是莱曼模型，平均剂量模型，并行架构模型，和一个模型的基础上接受超过指定剂量的器官的体积（“截止剂量”模型）。结果：对于每个模型，适合晚期直肠出血数据略有改善时，分析是基于直肠DWH，而不是DVH。此外，截止剂量和平行结构模型的结果是一致的，彼此的DWH数据，但不为DVH数据。对于DWH数据，如果80%或更多的直肠壁暴露于大于32戈伊的剂量，两种模型均预测2年内2级或更严重的晚期直肠出血的发生率为50%或更高。如果直肠壁的平均剂量超过53.2戈伊，直肠出血的发生率也预测为50%或更高。结论：一个一致的，虽然适度的，改善发生在适合的NTCP模型UTMDACC 2年晚期直肠出血数据时，适合是基于直肠剂量壁直方图，而不是整个直肠的剂量体积直方图，包括内容。(C)2004年爱思唯尔公司
Purpose: To compare the fits of normal-tissue complication probability (NTCP) models based on rectal dose-wall histograms (DWHs) vs. dose-volume histograms (DVHs) when the two are used to analyze a common set of late rectal toxicity data.Methods and Materials: Data were analyzed from 128 prostate cancer patients treated with 3-dimensional conformal radiotherapy (3D-CRT) at The University of Texas M.D. Anderson Cancer Center (UTMDACC). The DVH for total rectal volume, including contents, was obtained for each patient from the treatment-planning system. A DWH was also computed, using the outer rectal contour plus an autogenerated inner contour that corresponds to an assumed 3-mm rectal wall thickness. The endpoint for analysis was Grade 2 or higher late rectal bleeding within 2 years of treatment; all patients had at least 2 years of follow-up. Four different NTCP models were fitted to the response data by using either the DVH or the DWH to describe the dose distribution to rectum or rectal wall, respectively. The 4 models considered were the Lyman model, the mean dose model, the parallel-architecture model, and a model based on the volume of a organ receiving more than a specified dose (the "cutoff-dose" model).Results: For each of the models, the fit to the late rectal bleeding data was slightly improved when the analysis was based on the rectal DWH instead of on the DVH. In addition, the results of the cutoff dose and parallel architecture models were consistent with one another for the DWH data but not for the DVH data. For the DWH data, both models predict a 50% or higher incidence of Grade 2 or worse late rectal bleeding within 2 years if 80% or more of the rectal wall is exposed to doses greater than 32 Gy. A 50% or higher incidence of rectal bleeding is also predicted if the mean dose to rectal wall exceeds 53.2 Gy.Conclusions: A consistent, although modest, improvement occurs in the fits of NTCP models to the UTMDACC 2-year late rectal bleeding data when the fit is based on the rectal dose-wall histogram instead of on the dose-volume histogram for entire rectum, including contents. (C) 2004 Elsevier Inc.