食管癌放疗的剂量学和临床疗效研究

Dosimetry and Clinical Efficacy of Radiotherapy for Esophageal Cancer

目的比较食管癌放疗中容积旋转调强放疗(RapidArc)和静态调强放疗(sIMRT)的剂量学、毒副反应发生率和治疗反应率差异。方法收集2018年11月~2019年8月安徽医科大学第一附属医院68例经病理诊断为食管鳞癌的患者资料,按照不同放疗方法分为RapidArc组(20例),sIMRT组(48例)。比较两组靶区的适形性指数(CI)、均匀性指数(HI)和机器跳数(MU)、危及器官受量、毒副反应发生率和治疗反应率。结果RapidArc组CI高于sIMRT组(0.79±0.06 vs 0.72±0.10),且MU小于sIMRT组[(445.52±65.63)MU vs(554.62±106.08)MU](P<0.05),两组HI比较,差异无统计学意义(P>0.05)。RapidArc组胸上段食管癌的双肺V30、心脏V30、V40、Dmean、脊髓D2均小于sIMRT组(P<0.05);胸中段的心脏V30、V40、Dmean,脊髓V20小于sIMRT组(P<0.05);胸下段的脊髓V5、V20上小于sIMRT组(P<0.05)。两组毒副反应发生率和治疗反应率比较,差异无统计学意义(P>0.05)。结论RapidArc能显著提高靶区适形度,并降低肺高剂量区、心脏和脊髓受量,但其剂量学优势能否转化为临床获益仍待进一步考证。

Objective To compare the dosimetry,incidence of toxic and side effects,and treatment response rates of volumetric modulated arc radiotherapy(RapidArc)and static intensity modulated radiotherapy(sIMRT)in esophageal cancer radiotherapy.Methods From November 2018 to August 2019,68 patients with pathologically diagnosed esophageal squamous cell carcinoma were collected from the First Affiliated Hospital of Anhui Medical University.According to different radiotherapy methods,they were divided into RapidArc group(20 cases)and sIMRT group(48 cases).The conformation index(CI),homogeneity index(HI),monitor units(MU),the dose to organs at risk,the incidence of toxic and side effects,and the response rate of treatment were compared between the two groups.Results The CI of the RapidArc group was higher than that of the sIMRT group(0.79±0.06 vs 0.72±0.10),and the MU was smaller than that of the sIMRT group[(445.52±65.63)MU vs(554.62±106.08)MU](P<0.05).There was no significant difference in HI between the two groups(P>0.05).The lungs V30,heart V30,V40,Dmean,and spinal cord D2 of the upper thoracic esophageal cancer in the RapidArc group were all smaller than those in the sIMRT group(P<0.05).The heart V30,V40,Dmean,and spinal cord V20 in the middle of the chest were less than sIMRT group(P<0.05);the lower spinal cord V5 and V20 were smaller than the sIMRT group(P<0.05).There was no significant difference in the incidence of side effects and treatment response between the two groups(P>0.05).Conclusion RapidArc can significantly increase the conformity of the target area and reduce the volume of high-dose lung,heart and spinal cord.However,whether its dosimetric advantages can be translated into clinical benefits remains to be further investigated.