肺泡软组织肉瘤（ASPS）是罕见的软组织肉瘤，预后差且没有确立的疗法。最近，有报道显示免疫检查点抑制剂有良好的疗效。我们进行了一项由研究者发起的多中心、单组、2期研究，研究对象为晚期ASPS的成人和儿童患者。受试者接受抗程序性死亡配体1（PD-L1）药物阿特伊珠单抗静脉注射，剂量为1200毫克（年龄≥18岁患者）或以体重每千克15毫克，最高剂量为1200毫克（年龄<18岁患者），每21天一次。研究终点包括根据实体瘤反应评估标准（RECIST） 1.1版本的客观反应、反应持续时间和无进展生存期，以及多级药物作用的药代动力学生物标志物。共评估了52名患者。52名患者中有19名（37%）出现了客观反应，其中完全缓解1例，部分缓解18例。反应的中位时间为3.6个月（范围2.1至19.1个月），反应持续时间的中位值为24.7个月（范围4.1至55.8个月），无进展生存期的中位值为20.8个月。7名患者在进行了2年治疗后进行了治疗间歇期，但仍保持反应，直至截止数据日期。没有记录到与治疗相关的4级或5级不良事件。尽管在程序性死亡1和PD-L1的基线表达变量上，仍然观察到反应。阿特伊珠单抗在约三分之一的晚期ASPS患者中有效产生持久反应。（本研究由国家癌症研究所等资助；ClinicalTrials.gov编号，NCT03141684）.版权©2023 Massachusetts Medical Society.

Alveolar soft part sarcoma (ASPS) is a rare soft-tissue sarcoma with a poor prognosis and no established therapy. Recently, encouraging responses to immune checkpoint inhibitors have been reported.We conducted an investigator-initiated, multicenter, single-group, phase 2 study of the anti-programmed death ligand 1 (PD-L1) agent atezolizumab in adult and pediatric patients with advanced ASPS. Atezolizumab was administered intravenously at a dose of 1200 mg (in patients ≥18 years of age) or 15 mg per kilogram of body weight with a 1200-mg cap (in patients <18 years of age) once every 21 days. Study end points included objective response, duration of response, and progression-free survival according to Response Evaluation Criteria in Solid Tumors (RECIST), version 1.1, as well as pharmacodynamic biomarkers of multistep drug action.A total of 52 patients were evaluated. An objective response was observed in 19 of 52 patients (37%), with 1 complete response and 18 partial responses. The median time to response was 3.6 months (range, 2.1 to 19.1), the median duration of response was 24.7 months (range, 4.1 to 55.8), and the median progression-free survival was 20.8 months. Seven patients took a treatment break after 2 years of treatment, and their responses were maintained through the data-cutoff date. No treatment-related grade 4 or 5 adverse events were recorded. Responses were noted despite variable baseline expression of programmed death 1 and PD-L1.Atezolizumab was effective at inducing sustained responses in approximately one third of patients with advanced ASPS. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT03141684.).Copyright © 2023 Massachusetts Medical Society.