Clinical Outcomes and Molecular Predictors of Pembrolizumab (Keytruda) as a PD-1 Immune Checkpoint Inhibitor in Advanced and Metastatic Cervical Cancer: A Systematic Review and Meta-Analysis

Abstract

This systematic review evaluates the clinical outcomes and molecular predictors of response to pembrolizumab in patients with advanced and metastatic cervical cancer. We adhered to the PRISMA guidelines for systematic reviews, conducting a database search in PubMed, Scopus, and Embase. The eligibility criteria centered on clinical outcomes, including the overall survival (OS), progression-free survival (PFS), and immune-related biomarkers post-pembrolizumab therapy. We included both prospective and retrospective studies that detailed clinical outcomes and molecular characteristics predictive of therapeutic response. Our search yielded six studies involving 846 patients treated with pembrolizumab from 2017 to 2022. The meta-analysis of these studies showed that pembrolizumab, used as monotherapy or in combination with chemotherapy, extended the OS by a weighted median of 10.35 months and the PFS by 8.50 months. The treatment demonstrated a pooled objective response rate (ORR) of 22.39%, although the I2 test result of 67.49% showed a high heterogeneity among the studies. Notably, patients with high PD-L1 expression (CPS ≥ 10) experienced improved outcomes in terms of the PFS and OS. The most common complications were fatigue, diarrhea, and immune-related adverse events. Pembrolizumab significantly enhances clinical outcomes in metastatic cervical cancer, particularly among patients with high PD-L1 expression. The drug maintains a good safety profile, reinforcing its treatment potential for patients with advanced and metastatic cervical cancer. Future studies should explore long-term effects and strategies to integrate pembrolizumab optimally into current treatment regimens, aiming to maximize patient benefits and effectively manage side effects.