摘要目的 比较宫颈癌腔内联合组织间插植三维后装计划中模拟退火逆向优化(IPSA)和混合逆向优化(HIPO)剂量分布的差异,为宫颈癌腔内联合组织间插植后装治疗逆向计划优化方法的选择提供依据.方法 选取2016年12月至2017年5月于河北省沧州中西医结合医院43例宫颈癌患者资料,所有患者原后装治疗计划采用IPSA优化,基于原图像信息,给定同样的初始约束条件,不进行手动优化,直接计算IPSA和HIPO计划,对高危靶区(HR-CTV)剂量体积参数D90、D100、V100％,以及均匀性指数(HI)、适形指数(CI)、危及器官(OAR)(膀胱、直肠和乙状结肠)D2cm3的数据进行评价.结果 两组间HR-CTV的D90、D100以及CI剂量差异无统计学意义(P＞0.05),但HIPO组HR-CTV的V100％为(87.72±0.49)％;HI为(0.51±0.08),明显高于IPSA组的(85.01±0.55)％,HI(0.42±0.06),差异具有统计学意义(t=2.54、3.02,P＜0.05).对于OAR,与IPSA计划相比,HIPO计划中膀胱的D2cm3(3.42 ±0.17)Gy,直肠的D2cm3(3.04±0.37)Gy,明显低于IPSA计划膀胱的D2cm3(3.57±0.28)Gy,直肠的D2cm3(3.21±0.48) Gy,差异具有统计学意义(t=0.27、0.19,P＜0.05).乙状结肠D2cm3剂量两者差异无统计学意义.结论 在宫颈癌腔内联合组织间插植后装治疗中,采用HIPO优化比IPSA优化可以获得更好的靶区HI以及减少膀胱和直肠的受照剂量.

abstractsObjective To compare the difference of dose distribution between inverse planning simulated annealing (IPSA) and hybrid inverse treatment planning and optimization (HIPO) in 3D brachytherapy plan of cervical cancer,and to provide evidence for selection of reverse planning optimization method for cervical cancer brachytherapy.Methods From Dec 2016 to May 2017,totally 43 cases of patients with cervical cancer radical surgery were selected.Original IPSA brachytherapy treatment plan optimization was applied to all cases.Based on the information of original image,IPSA and HIPO plans were established according to the same initial conditions.Parameters of Dg0,D100,V100％,Homogeneity Index (HI),and conformal index (CI) of the bladder,rectum and sigmoid D2 cm3 data for High-Risk Clinical Target Volume (HR-CTV) were assessed.Results There was no statistically significant difference in D90,D100 and CI for HR-CTV between the two groups.But the V100％ of HR-CTV in HIPO group was significantly higher than that in IPSA group [(87.72 ±0.49)％ vs.(85.01 ± 0.55)％,t =2.54,P ＜0.05].Furthermore,HI in HIPO group was (0.51 ±0.08),which was higher than that in IPSA group (0.42 ± 0.06),and the difference was statistically significant (t =3.02,P ＜ 0.05).Compared with IPSA,bladder D2 cm3 and rectum D2 cm3 [(3.04 ± 0.37) Gy] for HIPO plan were lower [(3.42 ± 0.17) Gy vs.(3.57 ± 0.28) Gy,(3.04 ± 0.37) Gy vs.(3.57 ± 0.28) Gy],which had reached statistical significance (t =0.27,0.19,P ＜ 0.05).There was no statistical significance in the D2 cm3 dose of sigmoid.Conclusions In the treatment of cervical cancer,better target area HI and less irradiated dose of bladder and rectum can be obtained by HIPO optimization than IPSA optimization.