宫颈癌后装治疗常规计划与逆向计划剂量学对比

目的对比分析宫颈癌常规计划和逆向计划（即模拟退火逆向优化计划）的剂量学差异。方法选取宫颈癌内外照射联合根治性放疗的患者20例,每例患者制定两个治疗计划：一个为基于A点给定处方剂量的常规计划;另一个为逆向计划,先满足靶区,优化时,当临床靶区(CTV)的90％处方剂量体积大于90％ CTV时即达到优化目标,否则调节目标函数的权重配比,重新优化,直到达到优化目标。结果逆向计划的90％处方剂量体积和100％处方剂量体积及100％目标体积受量[(94±15)％、(90±18)％、(54±10)％]均优于常规计划[(60±17)％、(56±14)％、(29±9)％](P＜0.05),同时危及器官亦得到较好的保护。结论逆向优化的治疗计划具有节省时间,提高靶区剂量,减少危及器官受量的优势。

Comparison of conventional plan and inverse optinized plan in cervical cancer brachytherapy dosemetric

Objective To compare and analyze conventional plan and inverse optimized plan in dosemetric of cervical cancer. Method Twenty cases of cervical cancer treated with combination radical radiotherapy of EBT were selected,every case had two plans: one was conventional plan based A point prescription dose, the other was inverse optimized plan (IPSA, inverse planning with simulated annealing)based volume object dose. Results IPSA plans provided better values compared with the conventional plans in 90％ prescription dose volume V90[ (94 ± 15 )％ vs. (60 ± 17 )％], 100％ prescription dose volume V100[(90 ± 18)％ vs. (56 ± 14)％]and 100％ treatment volume dose D100[(54 ± 10)％ vs. (29 ±9)％](P ＜0.05),respectively. Meanwhile the organ at risk received lower dose volume. Conclusions Plans generated using IPSA provide higher dose to the target volume but with lower dose to normal structure and less time. This study can help to guide the clinical application.