容积旋转调强与固定野调强在晚期宫颈癌放疗的剂量学比较及疗效观察

目的 比较容积旋转调强（RapidArc）和固定野调强（IMRT）技术在宫颈癌根治性放疗的剂量学参数、急性不良反应发生率及疗效。方法 回顾性分析43例局部晚期（II_b~IV）宫颈癌患者，其中22例行容积旋转调强放疗，21例行固定野调强放疗，处方剂量50.4 Gy/28次，比较两组靶区剂量适形度、均匀性、靶区及危及器官的剂量、机器跳数及治疗时间；对比两组患者治疗期间的急性肠道及膀胱反应发生率；对比两组患者的完全缓解率和有效率。结果 与IMRT计划相比，RapidArc计划的靶区适形性指数CI略好，但差异无统计学意义（P > 0.05）；两组计划的靶区均匀性指数HI比较，差异无统计学意义（P > 0.05）。RapidArc计划中膀胱的V₄₀、V₅₀以及直肠的V₃₀、V₄₀、V₅₀均低于IMRT计划（t=-2.386、-2.397、-5.525、-2.883、-2.686，P < 0.05），RapidArc计划中股骨头的平均剂量低于IMRT计划（t=-2.395，P < 0.05）。RapidArc较IMRT平均MU减少了53.15%，治疗所需平均时间缩短了62.14%。两组患者肠道、膀胱急性反应发生率相近。两组患者完全缓解率和有效率相近。结论 晚期宫颈癌根治性放疗中，采用RapidArc技术可以降低危及器官受量，缩短患者的治疗时间。

Dosimetry and efficacy between RapidArc and intensity-modulated radiotherapy for locally advanced cervical carcinoma

Objective To analyze the difference of dosimetry and evaluate clinical efficacy and acute toxicity reaction between RapidArc and fixed gantry angle dynamic intensity modulated radiotherapy(IMRT) in advanced cervical carcinoma.Methods A total of 43 patients with locally advanced cervical cancer were studied,including 22 patients treated with RapidArc and 21 patients with IMRT.All plans were prescribed 50.4 Gy in 28 fractions.The conformity index and homogeneity index of the targets,the monitor units(MUs)and delivery time were compared. Incidence of acute intestinal and bladder side effects and rates of efficacy were calculated. Results The conformity index of RapidArc was better compared to IMRT. The V₄₀ and V₅₀ of bladder and V₃₀,V₄₀ and V₅₀ of rectum planned by RapidArc was significantly lower than that by IMRT(t=-2.386,-2.397, P < 0.05; t=-5.525,-2.883,-2.686, P < 0.05). The mean dose of femoral head planned by RapidArc was also significantly lower (t=-2.395,P < 0.05). For RapidArc, mean MU and treatment time were reduced by 53.15%, and 62.14%, respectively.There was no difference in the incidence of acute intestinal and bladder toxicity and rates of complete remission and efficacy between the two groups. Conclusions In dosimetric analysis,RapidArc showed advantage in protecting organs at risk and reducing treatment time in radical radiotherapy for locally advanced cervical carcinoma.