Abstract 6118: Sex-related disparity in immune checkpoint inhibitor benefit for patients with esophageal squamous cell carcinoma: A systematic review and meta-analysis

Abstract

Abstract Sex-related dimorphism in cancer incidence and immune response is widely recognized, yet the impact of an individual's sex on the effectiveness of Immune Checkpoint Inhibitors (ICIs) for patients with advanced esophageal squamous cell carcinoma (ESCC) remains poorly understood. In this study, we conducted a comprehensive meta-analysis to evaluate the heterogeneity of ICIs in patients with advanced ESCC. We collected studies from PubMed, MEDLINE, Embase, and Scopus, spanning from the inception of the databases to September 30, 2023. These studies focused on phase III randomized trials comparing first-line ICIs (PD-1/PD-L1) plus chemotherapy with chemotherapy alone for advanced or metastatic ESCC. Additionally, we reviewed abstracts and presentations from AACR, ASCO, ESMO, and WCLC. Inclusion criteria mandated the reporting of overall survival (OS) data stratified by sex and nonselective baseline PD-L1 expression. The study adhered to Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The analysis included 6 randomized clinical trials comprising 3603 ESCC patients, of whom 3090 (85.8%) were male and 513 (14.2%) were female. A significant OS benefit was observed for ICIs plus chemotherapy in all patients (HR, 0.68; 95% CI, 0.62-0.74; P < 0.001). Similarly, ICIs plus chemotherapy correlated with a significantly prolonged OS in males (HR, 0.67; 95% CI, 0.61-0.74, P < 0.001). However, there was no significant OS benefit observed in females with ICIs plus chemotherapy (HR, 0.79; 95% CI, 0.58-1.09; P = 0.148). Females had a tendency toward less benefit than males (pooled HR, 1.18; 95% CI, 0.89-1.57; P = 0.245). Our findings suggest that there is no statistically significant association between patient sex and the efficacy of ICIs for ESCC patients. Importantly, we report, for the first time, a lack of survival benefit with the ICI plus chemotherapy regimen in the first-line setting compared to chemotherapy alone in female ESCC patients. Citation Format: Chaoqi Zhang, Peng Wu, Jingjing Liu, Dongyu Li, Nan Sun, Jie He. Sex-related disparity in immune checkpoint inhibitor benefit for patients with esophageal squamous cell carcinoma: A systematic review and meta-analysis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 6118.