Supplementary Material for: Poor Treatment Outcomes with Second-Line Chemotherapy in Advanced Synovial Sarcoma

Introduction: Synovial sarcoma predominantly affects adolescents and young adults. Doxorubicin with or without ifosfamide therapy is the standard first-line treatment for unresectable or metastatic synovial sarcoma. However, there is no standard second-line chemotherapy regimen. The purpose of the current study was to evaluate the outcomes of second-line chemotherapy for patients with synovial sarcoma. Methods: We retrospectively evaluated the outcomes of 61 patients with unresectable or metastatic synovial sarcoma who had received first-line chemotherapy at our institution between 1997 and 2017. Patients who received second-line chemotherapy were included in the analysis. Outcomes of the chemotherapy were evaluated. Results: Among the 61 patients treated with first-line chemotherapy, we identified 32 patients who received second-line chemotherapy. Most patients (62.5%) were under 40 years of age. Regarding second-line chemotherapy regimens, 6 (18.8%) patients were treated with doxorubicin with/without ifosfamide, 6 (18.8%) with ifosfamide and etoposide, 4 (12.5%) with docetaxel and gemcitabine, 5 (15.6%) with pazopanib, 2 (6.2%) with trabectedin, and 1 (3.1%) with eribulin. The overall response rate according to the Response Evaluation Criteria in Solid Tumors for all patients was 9.4%. Eleven patients (34.3%) achieved disease-control for > 6 months. The median follow-up duration was 15.2 months. The 1-year progression-free and overall survival rates were 33.1% and 67.1%, respectively. Conclusion: Our exploratory study revealed that the response rate of second-line chemotherapy regimens for patients with synovial sarcoma was 9.4%. Therefore, there is an urgent need to develop more active therapeutic regimens for synovial sarcomas.

引言：滑膜肉瘤（Synovial Sarcoma）主要发病人群为青少年及年轻成人。含或不含异环磷酰胺（Ifosfamide）的多柔比星（Doxorubicin）方案，是不可切除或转移性滑膜肉瘤的标准一线治疗方案，但目前尚无标准二线化疗方案。本研究旨在评估滑膜肉瘤患者二线化疗的临床结局。
方法：本研究回顾性分析了1997年至2017年间，本机构收治的61例接受过一线化疗的不可切除或转移性滑膜肉瘤患者，纳入其中接受二线化疗的患者进行分析，并评估其化疗疗效。
结果：在接受一线化疗的61例患者中，共32例接受了二线化疗。其中大多数患者（62.5%）年龄小于40岁。二线化疗方案方面，6例（18.8%）采用含/不含异环磷酰胺（Ifosfamide）的多柔比星（Doxorubicin）方案，6例（18.8%）采用异环磷酰胺（Ifosfamide）联合依托泊苷（Etoposide）方案，4例（12.5%）采用多西他赛（Docetaxel）联合吉西他滨（Gemcitabine）方案，5例（15.6%）采用帕唑帕尼（Pazopanib）方案，2例（6.2%）采用曲贝替定（Trabectedin）方案，1例（3.1%）采用艾瑞布林（Eribulin）方案。根据实体瘤疗效评价标准（Response Evaluation Criteria in Solid Tumors）评估，所有患者的客观缓解率为9.4%。11例患者（34.3%）实现了超过6个月的疾病控制。中位随访时间为15.2个月。1年无进展生存率和总生存率分别为33.1%和67.1%。
结论：本探索性研究显示，滑膜肉瘤患者二线化疗方案的客观缓解率为9.4%。因此，亟需开发更为有效的滑膜肉瘤治疗方案。