单管式子宫颈癌后装施源器前瞻性随机对照Ⅱ期临床研究3年远期疗效总结

Evaluation of clinical efficacy and safety of single-channel intracavitary applicator for uterine cervical cancer:3-year long-term results of a prospective randomized phaseⅡclinical trial

目的探讨自主研发的单管式子宫颈癌后装施源器,相比于标准Fletcher三管施源器的3年远期生存结果以及晚期损伤情况。方法选取2011—2017年间西南医科大学附属医院就诊的子宫颈癌初诊患者,随机分为外照射+单管式后装组(专利单管组)和外照射+Fletcher三管式后装组。外照射采用6MV X线四野盒式或前后对穿野照射,30Gy后改野挡铅行后装治疗,1次/周,剂量为A点7Gy,共5~6次(A点2Gy等效生物剂量80~90Gy)。外照射时同步使用顺铂(40mg/m^(2))化疗,1次/周,治疗结束随访其疗效及不良反应并对比。结果符合入组条件并完成治疗,Fletcher三管组150例,专利单管组149例。截至2020年12月全部患者随访时间满3年,中位随访时间61个月。Fletcher三管组的3年总生存率、无进展生存率和局部无失败生存率分别为76.3%、78.1%和75.4%,而专利单管组分别为83.8%、80.3%和85.5%。3-4级晚期放射性直肠炎三管组3.3%,单管组6.7%(P=0.122)。3-4级晚期放射性膀胱炎三管组1.3%,单管组0.7%(P=1.000)。结论专利单管式子宫颈癌后装施源器与标准Fletcher三管施源器3年生存数据疗效相当且晚期不良反应相似。

Objective To evaluate the 3-year survival outcomes and late injury between the self-designed patent single-channel applicator,which was modified from the traditional tandem applicator and wrapped with a oval-shield alloy around the source channel and standard Fletcher-type applicator in the high-dose-rate brachytherapy for cervical cancer.Methods Patients initially diagnosed with cervical cancer in the Affiliated Hospital of Southwest Medical University from December 2011 to April 2017 were enrolled and randomly assigned into the external beam radiotherapy(EBRT)+single-channel intracavitary applicator group(the patent single-channel group)and EBRT+the Fletcher applicator group.The whole pelvis irradiation was delivered with 6-MV photons via a four-field box variant or anterior and posterior parallel fields.Five to six fractions of intracavitary brachytherapy were performed at a dose of 7Gy at point A once a week after 30Gy(Equivalent Dose in 2Gy at point A:80-90Gy).Chemotherapy was given with intravenous injection of cisplatin at a dose of 40mg/m^(2) once weekly during EBRT.Clinical efficacy and safety were evaluated after corresponding treatment.Results In total,150 eligible cases were assigned into the Fletcher applicator group and 149 cases into the patent single-channel group.Up to December 2020,all patients had been followed up for 3 years,and the median duration of follow-up was 61 months.In the Fletcher group,the 3-year overall survival,progression-free survival and locoregional failure-free survival was 76.3%,78.1%and 75.4%,and 83.8%,80.3%and 85.5%in the single-channel group,respectively.In the Fletcher group,the cumulative rate of grade 3-4 late rectal complications was 3.3%and 6.7%in the single-channel group(P=0.122).The cumulative rate of grade 3-4 bladder complications was 1.3%in the Fletcher group and 0.7%in the single-channel group(P=1.000).Conclusion The self-designed patent single-channel intracavitary applicator yields equivalent long-term clinical efficacy and safety to the standard Fletcher-type three-channel applicator in the HDR brachytherapy for uterine cervical cancer.