调强适形放疗治疗成人脑膜旁横纹肌肉瘤

摘要

目的:横纹肌肉瘤(rhabdomyosarcoma,RMS)多见于儿童,在成人很少见,特别是头颈部脑膜旁横纹肌肉瘤,预后较儿童差;探讨调强适形放疗(intensity modulated radiation therapy,IMRT)治疗成人脑膜旁横纹肌肉瘤的临床结果.方法:从2008年12月31日至2015年7月10日我科连续收治11例均经病理证实的无远处转移成人脑膜旁横纹肌肉瘤,女性7例,男性4例,中位年龄36岁(21~55岁),出现临床症状至确诊中位时间8周(4~12周),主要症状为头痛、鼻堵、溢泪、眼眶疼痛、治疗眼球突出、颅神经麻痹等非特异性症状;患者均行增强MRI和CT检查,临床分期:Ⅱ期2例,Ⅲ期9例,其中诊断时7例有淋巴结转移,均无远处转移.病理类型:腺泡型横纹肌肉瘤7例,胚胎型横纹肌肉瘤4例;治疗方式:手术+放疗+化疗治疗8例,放疗+化疗治疗2例,手术+放疗1例;化疗方案均为IE方案(异环磷酰胺,表阿霉素);11例全部行调强适形放疗,10例行辅助放疗(60~66 Gy),1例给予根治量放疗(69.96 Gy);Kaplan-Meier法计算3年累积总生存率.结果:全组中位随访16个月(8~88个月),Kaplan-Meier法计算3年累积总生存率约为47.1%,估计平均生存时间48.7个月,中位生存时间18个月,最长1例无病生存88个月,3年局部控制率为72.7%;失败类型:远处失败共5例,其中远处转移同时伴局部和淋巴结失败1例(未做手术),远处转移和淋巴结同时失败1例(未做淋巴结区照射),远处转移和局部复发1例(未做手术),2例单纯远处转移(1例未做化疗,1例仅作2周期巩固化疗),1例单纯淋巴结失败(未做淋巴结区照射).死亡5例,均有远处转移者.结论:成人脑膜旁RMS是侵袭性很强恶性肿瘤,诊断时多侵犯颅底、颅内或眼眶内,很难手术彻底切除,手术联合IMRT放疗可获得较高局部控制率;尽管采用综合治疗其预后仍然较儿童横纹肌肉瘤差,主要失败方式为远处转移.%Objective:Rhabdomyosarcoma(RMS)is a pediatric sarcoma rarely occurring in adults.For unknown reasons,adults with RMS,especially for parameningeal rhabdomyosarcoma(PM-RMS),have worse outcomes than do children.We analyzed results of adult parameningeal RMS treated with multimodality protocols.Methods:Eleven consecutive patients with histologically proven RMS treated with multimodality protocols between December 31st,2008 and July 10th,2015 were retrospectively reviewed.There were 7 females and 4 males.The median age was 36 years old(range 21~55 years old).The median time from the onset of symptoms to diagnosis was approximately 8 weeks (range 4~12 weeks).The clinical symptoms were nonspecial,included headache,nasal obstruction,epiphora,perior-bital pain,protopsis,cranial nerve palsy,and so on.All patients had enhanced magnetic resnance imaging(MRI) scans and computed tomography(CT)scans of the head and neck.Most(9/11)had gradeⅢdisease.Histology was alveolar in 7 cases and embryonal in 4 cases.All patients were treated using simultaneous-boost intensity modulated radiation therapy(SIB-IMRT)as a part of multimodality therapy,with fraction sizes of 2.12 Gy to the gross target volumes(GTV),2.0 Gy to the high-risk clinical target volumes(CTV1),1.8 Gy to the elective clinical target vol-umes(CTV2).The radiation dose to the GTV was 69.96 Gy.The radiation dose to the CTV1 ranged from 60 to 66 Gy. The dose of CTV2 was 50.4 Gy.One patient didn't receive elective cervical lymph node irradiation.One patient un-derwent definitive radiation therapy.Ten patients underwent adjuvant radiation therapy(postoperative:n=6,preopera-tive:n=4).Surgery was performed in 9/11 patients.Among them,one patient had residual macroscopic disease,one patient had positive margin after surgery.One patient after preoperative radiation refused surgery.Chemotherapy was given to 10 of 11 patients,with ifosfamide and pharmorubicin.Six patients received 2 to 4 courses of induction chemo-therapy.Four patients received 2 courses of concurrent chemoradiotherapy.Eight patients received 2 to 6 courses of consolidation chemotherapy.The Kaplan-Meier method was used to calculate the the actuarial rates of overall surviv-al(OS)and local control(LC).Estimates of overall survival time were calculated from the time of initial diagnosis. Results:The median follow-up period was 16 months(range 8~88 months).The 3-year estimates of OS rate was 47.1%.Estimates of average survival time and the median overall survival time were 48.7 months and 18 months,re-spectively.The 3-year local control rate was 72.7%.The patterns of failure:Local-regional recurrence with distant metastasis occurred in 1 patient(without surgery),regional and distant metastasis synchronously in 1 patient(without elective nodal irradiation),local and distant metastasis synchronously in 1 patient(without surgery),regional recur-rence alone in 1 patient(without elective nodal irradiation),and distant metastasis alone in 2 patients(one without chemotherapy,and another only had two courses of consolidation chemotherapy).Five patients had died,all with dis-tant metastasis.Conclusion:Adult parameningeal RMS is highly aggressive malignant tumors.Due to the high rate of intraorbital,or intracranial extension at the time of diagnosis,complete resection with negative resection margins and acceptable morbidity is difficult to achieve.Local control is excellent in patients receiving surgery and IMRT for adult pa-rameningeal RMS.Adult parameningeal RMS has worse outcomes than do children despite aggressive multimodality man-agement.The main patterns of failure is distant metastasis.