非小细胞肺癌大体靶区勾画差异对正常组织并发症概率的影响

目的 :评价不同医生勾画的非小细胞肺癌 (non smallcelllungcancer ,NSCLC)大体靶区 ( grosstumorvolume ,GTV )差异对正常组织并发症概率 (normaltissuecomplicationprobabili ty ,NTCP)的影响。方法 :选取 5例拟行三维适形放疗的NSCLC患者 ,由 5名医生独立勾画GTV ,然后以不同医生勾画的GTV为基础 ,制定适形放射治疗计划 ,时间剂量分割模式为每次 2Gy ,每周 5次 ,肿瘤总剂量为 60Gy。按Kutcher的算法计算肺脏和心脏的NTCP。结果 :不同医生勾画的 5例患者的GTV最大差异最小为 1 2 8倍 ,最大为 2 94倍 ,虽然基于不同医生勾画的GTV计算的各脏器的NTCP差异无统计学意义 ,但某些患者其NTCP的差异非常大。结论 :部分NSCLC大体靶区勾画的差异所导致的肺脏和心脏NTCP的变化不容忽视

Effect of discrepancy of gross tumor volume delineation of non-smallcell lung carcinoma on normal tissue complication probability

OBJECTIVE: To evaluate the effects of differences of GTVs of non-small cell lung cancer (NSCLC) defined by different physicians on normal tissue complication probability (NTCP).METHODS:GTVs of 5 patients with NSCLC selected were delineated independently by 5 physicians. The three dimensional conformal radiotherapy plans based on the GTVs were optimized. The time-dose-fractionation was 60 Gy in 2 Gy per-fraction, 5 times a week. NTCPs of bilateral lungs and heart were calculated.RESULTS:The maximum differences of GTVs of every patient defined by different physicians ranged from 1.28 to 2.94 times. Though the differences of NTCPs of lung and heart were not statistically significant, the differences of NTCPs in some individual patients were pretty big. CONSLUSION:The effects of NTCPs in some patients caused by discrepancy of GTVs of NSCLC delineated by different physicians are not negligible.