宫颈癌术后容积旋转调强放射与适形调强放疗的剂量学比较

Comparison of dosimetry of volumetric modulated arc therapy and intensity-modulated radiotherapy after cervical cancer surgery

目的 观察宫颈癌术后容积旋转调强放疗(VMAT)与适形调强放疗(IMRT)的剂量学差异。方法 回顾性分析2018年12月至2021年12月广东省湛江中心人民医院收治的103例宫颈癌术后进行VMAT或IMRT的患者的临床资料,根据不同放疗方法分为VMAT组(VMAT,n=53)和IMRT组(IMRT,n=50)。比较两组靶区剂量[最大剂量、最小剂量、平均剂量、靶区适形指数(CI)、靶区剂量均匀性指数(HI)]、危及器官受累剂量、机器跳数(MU)和治疗时间,统计两组治疗期间急性肠道及膀胱反应发生率。结果 两组靶区最大剂量、最小剂量、平均剂量比较差异均无统计学意义(P>0.05),VMAT组CI、HI水平明显高于IMRT组(P <0.05);VMAT组股骨头V20、V30、V40水平均明显低于IMRT组(P <0.05),两组直肠、小肠、膀胱、骨髓的最大剂量、平均剂量、V5、V10、V20、V30、V40水平及股骨头的最大剂量、平均剂量、V5、V10水平比较差异均无统计学意义(P>0.05);VMAT组MU、治疗时间均明显低于IMRT组(P <0.05);两组急性肠道及膀胱反应发生情况比较差异均无统计学意义(P>0.05)。结论 VMAT和IMRT对宫颈癌术后放疗患者均可达到靶区剂量要求和保护危及器官的目的,剂量学参数相当,但VMAT的加速器跳数和治疗时间明显减少,可提高治疗效率。

Objective To observe the dosimetry differences between volumetric modulated arc therapy(VMAT) and intensity-modulated radiotherapy(IMRT) after cervical cancer surgery.Methods The clinical data of103 patients who underwent VMAT or IMRT after cervical cancer surgery in our hospital were retrospectively analyzed between December 2018 and December 2021.According to different radiotherapy methods,the patients were divided into VMAT group(VMAT,n=53) and IMRT group(IMRT,n=50).The target volume dose [maximum dose,minimum dose,average dose,target volume conformity index(CI),target volume homogeneity index(HI)],involved dose of organs at risk,monitor unit(MU) and treatment time were compared between the two groups,and the incidence rates of acute intestinal reaction and bladder reaction in the two groups during treatment were statistically analyzed.Results There were no statistical differences in the target volume maximum dose,minimum dose and average dose between the two groups(all P>0.05).The Cl and HI in VMAT group were significantly higher than those in IMRT group(all P0.05).MU and treatment time in VMAT group were significantly lower or shorter than those in IMRT group(all P0.05).Conclusion Both VMAT and IMRT can achieve the target volume dose requirements and protect organs at risk in patients with after radiotherapy for cervical cancer,and both have equivalent dosimetry parameters,but VMAT significantly reduces the monitor unit and treatment time and can improve the treatment efficiency.