利用数学模型分析食管癌放疗体积演化

Analysis of the Evolution of Esophageal Tumor Volume in Radiotherapy Process Using a Mathematical Model

肿瘤放疗过程中体积变化间接地反映了放疗近期疗效及放疗计划优劣,利用数学模型分析肿瘤临床放疗体积的变化。遴选8例单纯适形放疗的食管癌患者,采用常规分割计划放疗,观测肿瘤体积的变化。基于LQ模型、肿瘤放射生物学4R理论中的再氧合和再增殖、非活性肿瘤细胞消亡建立肿瘤放疗体积演化的数学模型,利用数理模型分析食管癌放疗体积变化的临床实验数据,模型基本符合食管癌放疗中体积变化的趋势。根据模型分析结果,得到的相关参数用用于估算患者的生物有效剂量和再增殖出现时间,为评估预后和进一步治疗提供参考。

The volume change of tumor during radiotherapy processes indirectly reflects the short-term efficacy and the quality of radiotherapy planning. We analyzed clinical data of radiotherapy using a mathematical model in our study. First, we selected eight esophageal carcinoma patients with only using 3DRT and conventional dose fractionation schemes. And then we observed and measured the change of tumor volume during the radiotherapy. Based on the LQ model, repopulation and re-oxygenation in 4Rs, and the kinetics of doomed tumor disintegration, we established the mathematical model of tumor evolution in radiotherapy. And then we used the model to analyze the clinical trial data about esophageal carcinoma with radiotherapy. It was proved that the results of the model almost coincided with the clinical trial data. According to the analysis results, we could get the related radiohiology parameters to estimate biological effective dose and repopulation of patients. The mathematical model could provide reference for as- sessment of prognosis and further scheme of treatment.