Objective: To analyze the efficacy and prognostic factors in children with parameningeal rhabdomyosarcoma (PMRMS) treated by 125I brachytherapy combined with chemotherapy. Methods: A retrospective analysis of the clinical data of 33 pediatric patients treated with 125I brachytherapy combined with chemotherapy in Peking University Stomatological Hospital from July 2013 to October 2018 was carried out to analyze the efficacy and prognostic factors. Results: Among the 33 patients, 19 were males and 14 were females; the median age was 4 years old (1-12 years old). There were 17 cases with embryonic type, 9 cases with alveolar type, and 7 with undifferentiated type; 26 cases with original PMRMS, and 7 cases with recurrent PMRMS. The tumors occurred in subtemporal-mastoid area in 15 patients, while nasopalatine-paranasal area in 6 cases, and parapharyngeal-submandibular area in 12 cases. There were 28 patients in IRS Ⅲ, and 5 patients in IRS Ⅳ. As for the risk level, 28 cases were in the middle-risk group and 5 cases in the high-risk group. The median follow-up time was 52 months. The 1, 3, and 5-year local control rates were 87.9%, 58.6%, and 49.9%, and the 1, 3, and 5-year survival rates were 93.8%, 60.5%, and 47.5%, respectively. The 5-year local control rate and 5-year survival rate of 12 patients with the tumor in the parapharyngeal-submandibular area were 91.7% and 100%, respectively. The 5-year local control rate and 5-year survival rate of the 6 patients with tumor in the nasopalatine-paranasal area were both 83.3%. The 3-year local control rate and 3-year survival rate of the 15 patients with tumor in the subtemporal-mastoid area were 17.5% and 21.4%. The multivariate survival analysis using Cox proportional risk regression model showed that the tumor located in the subtemporal-mastoid area was an independent risk factor affecting the 5-year overall survival rate (HR=38.40, 95%CI: 4.87-302.52, P=0.001). Within 3 months after 125I seed implantation, the incidence of acute radiotherapy adverse reactions in all patients was 84.8% (28/33). Twenty-one patients (63.6%) had a grade 1 acute radiotherapy reaction, and 7 cases (21.2%) had a grade 2 acute radiotherapy reaction. No acute radiotherapy adverse reactions of grade 3 or 4 occurred. Three months after 125I seed implantation, the adverse reactions were significantly alleviated, and no adverse reactions of grade 3 or above such as skin ulcer or salivary gland fibrosis occurred, and no serious cranio-maxillofacial deformities occurred. Conclusions: 125I seed brachytherapy combined with chemotherapy has a definite clinical effect in the treatment of children with parameningeal rhabdomyosarcoma. The prognosis of rhabdomyosarcoma in the parapharyngeal-submandibular area and nasopalatine-paranasal area is better than that in the subtemporal-mastoid area.
目的： 分析125I粒子近距离放疗联合化疗对儿童脑膜旁横纹肌肉瘤（PMRMS）的疗效及其预后。 方法： 回顾性分析2013年7月至2018年10月在北京大学口腔医院采用125I粒子近距离放疗联合化疗治疗的33例PMRMS患儿的临床资料，分析其疗效和预后影响因素。 结果： 33例患儿中，男19例，女14例；年龄1~12岁，中位年龄4岁。胚胎型17例，腺泡型9例，多形型7例。原发PMRMS 26例，复发PMRMS 7例。颞下-乳突区15例，鼻腭-鼻旁区6例，咽旁-颌下区12例。美国儿童横纹肌肉瘤（RMS）协作组分期为Ⅲ期28例，Ⅳ期5例；中危组28例，高危组5例。中位随访时间52个月。33例儿童PMRMS的1、3和5年局部控制率分别为87.9%、58.6%和49.9%，1、3和5年生存率分别为93.8%、60.5%和47.5%。咽旁-颌下区患儿的5年局部控制率和5年生存率分别为91.7%和100%，鼻腭-鼻旁区患儿的5年局部控制率和5年生存率均为83.3%，颞下-乳突区患儿的3年局部控制率和3年生存率分别为17.5%和21.4%。Cox比例风险回归模型多因素分析显示，肿瘤位于颞下-乳突区是影响PMRMS患儿5年总生存率的危险因素（HR=38.40，95%CI：4.87~302.52，P=0.001）。粒子植入后3个月内，全组患儿的急性放疗不良反应发生率为84.8%（28/33）。21例（63.6%）患儿出现1级急性放疗反应，7例（21.2%）患儿出现2级急性放疗反应。无3级及以上急性放疗不良反应发生。粒子植入3个月后，急性放疗不良反应均有明显缓解，无皮肤溃疡、唾液腺纤维化等3级及以上远期放疗不良反应发生，无严重颅颌面畸形发生。 结论： 125I粒子近距离放疗联合化疗治疗儿童脑膜旁横纹肌肉瘤临床疗效肯定，肿瘤位于咽旁及鼻腭区的预后优于颞下-乳突区。.