Treatment with programmed cell death 1/programmed cell death ligand 1 inhibitors for Kaposi sarcoma: A systematic review and meta-analysis.

Abstract

e14584 Background: Kaposi Sarcoma (KS) is a cutaneous tumor of angioproliferative origin induced by the human gammaherpesvirus 8 (HHV-8). For many years, cytotoxic chemotherapy was the primary treatment for advanced disease with visceral involvement, despite its high toxicity rates and limited therapeutic efficacy. Immunotherapy, particularly inhibitors of Programmed Cell Death 1 (PD-1) and Programmed Cell Death Ligand 1 (PD-L1), has emerged as a promising treatment option with antitumor efficacy and a favorable safety profile. We conducted a meta-analysis to evaluate the efficacy and safety of this treatment for KS. Methods: A systematic search was conducted in Medline, Embase, Cochrane Library, and Web of Science to identify single-arm trials on PD-1/PD-L1 inhibitors in KS. Outcomes were expressed as proportions with 95% CIs. Heterogeneity was assessed using I², and significance was set at p < 0.05. Analyses were performed in RStudio 4.4.1. Results: In our meta-analysis, 4 studies were included, comprising a total of 76 patients, of whom 74 (97.3%) were men. Among the included patients, 27 (35.0%) had received chemotherapy as prior therapy, 17 (22.3%) had undergone radiotherapy, and 7 (9.2%) had been treated with interferon. In a pooled analysis, the Objective Response Rate (ORR) was 65% (95% CI: 0.54 to 0.75; P = 0.65; I² = 0%), with 17% (95% CI: 8 to 31; P = 0.56; I² = 0%) achieving Complete Response (CR), and the Disease Control Rate (DCR) was 91% (95% CI: 81 to 96; P = 0.75; I² = 0%). Regarding Adverse Events (AEs), pruritus was the most frequent, affecting 42% (95% CI: 16 to 73; P = 0.02; I² = 74%), followed by fatigue at 27% (95% CI: 0.08 to 0.60; P = 0.05; I² = 67%) and arthralgia at 14% (95% CI: 5 to 37; P = 0.06; I² = 60%). Conclusions: This systematic review and meta-analysis reinforce the antitumor activity of PD-1/PD-L1 inhibitors in patients with Kaposi's Sarcoma (KS). Despite the high rates of treatment-related adverse events associated with immunotherapy, most were clinically manageable.