Use of fractional dose-volume histograms to model risk of acute rectal toxicity among patients treated on RTOG 94-06

作者：Tucker Susan L^*; Michalski Jeff M; Bosch Walter R; Mohan Radhe; Dong Lei; Winter Kathryn; Purdy James A; Cox James D

来源：Radiotherapy and Oncology, 2012, 104(1): 109-113.

DOI：10.1016/j.radonc.2012.04.023

• Prostate cancer
• Acute rectal toxicity
• Dose-volume histogram
• Normal-tissue complication probability
• Lyman model

Background and purpose: For toxicities occurring during the course of radiotherapy, it is conceptually inaccurate to perform normal-tissue complication probability analyses using the complete dose-volume histogram. The goal of this study was to analyze acute rectal toxicity using a novel approach in which the fit of the Lyman-Kutcher-Burman (LKB) model is based on the fractional rectal dose-volume histogram (DVH). %26lt;br%26gt;Materials and methods: Grade %26gt;= 2 acute rectal toxicity was analyzed in 509 patients treated on Radiation Therapy Oncology Group (RTOG) protocol 94-06. These patients had no field reductions or treatment-plan revisions during therapy, allowing the fractional rectal DVH to be estimated from the complete rectal DVH based on the total number of dose fractions delivered. %26lt;br%26gt;Results: The majority of patients experiencing Grade %26gt;= 2 acute rectal toxicity did so before completion of radiotherapy (70/80 = 88%). Acute rectal toxicity depends on fractional mean rectal dose, with no significant improvement in the LKB model fit when the volume parameter differs from n = 1. The incidence of toxicity was significantly lower for patients who received hormone therapy (P = 0.024). %26lt;br%26gt;Conclusions: Variations in fractional mean dose explain the differences in incidence of acute rectal toxicity, with no detectable effect seen here for differences in numbers of dose fractions delivered.

• 出版日期2012-7