Use of immune checkpoint inhibitors in soft tissue sarcoma: A meta-analysis.

Abstract

e23560 Background: Soft tissue sarcomas (STS) have historically been treated with surgery, radiation, or chemotherapy. Recent studies and clinical trials have investigated the use of immune checkpoint inhibitors (ICI) either alone or in combination with chemotherapy. Here we present a meta-analysis examining ICI use in STS. Methods: A systemic search with terms encompassing STS and ICI was conducted in PubMed and Embase on January 11, 2026. A total of 1494 records were identified, which were imported into Rayyan, and titles were screened independently by 2 reviewers. 134 records were relevant, and full texts were reviewed. Only studies in which ICI was utilized for STS treatments were included. RevMan was used for analysis, and the Binary Random-Effects (RE) model was used for Pooled Proportions (PP) analyses. Results: ICI cohort had a total of 4455 patients. Using the RE model, the pooled proportions of patients achieving Complete Response (CR) was 1.7% (1.3% - 2.1%, p < 0.001, I^2 0), Partial Response (PR) was 17.7% (15.5-20.0, p < 0.001, I^2 79.057), and Stable Disease (SD) was 43% (39% - 47.1%, p < 0.001, I^2 84.044) while no response was seen in 33.5% patients (28.4% - 38.6%, p < 0.001, I^2 91.06). Overall Response Rate, (not including SD) was estimated to be 23.1% (20.4%-25.8%, p < 0.001). There was substantial heterogeneity across studies (I^2 86.629) for ORR. Current literature shows that using chemotherapy, mainly anthracycline based, has CR < 10%, PR 15-30%, and ORR 20-40%. Conclusions: Pooled data using ICI in sarcoma shows good overall response rates, especially the partial response rates. Current literature shows that using chemotherapy, mainly anthracycline based, has CR < 10%, PR 15-30%, and ORR 20-40%. Our data is very comparable to chemotherapy regimens. While meta-analysis results can be confounded by heterogeneity between studies, results of ongoing clinical studies that may result in near future may help better answer this question.