Prognostic factors of lenvatinib plus pembrolizumab therapy for advanced or recurrent endometrial cancer: analysis of a multicenter cohort study in Japan

Abstract Background Lenvatinib plus pembrolizumab (LP) therapy has emerged as an effective treatment for patients with advanced or recurrent endometrial cancer. However, limited data are available regarding its outcomes in real-world settings. This study aimed to identify prognostic factors associated with the efficacy of LP therapy. Methods This multicenter observational study was conducted across 15 institutions in Japan and examined patients with endometrial cancer, including uterine carcinosarcoma, who experienced disease progression after receiving at least one platinum-based chemotherapy, including adjuvant treatment, and subsequently received LP therapy. The prognostic factors for progression-free survival were assessed using a multivariate Cox proportional hazards model. Results A total of 105 patients met the inclusion criteria. Improved progression-free survival was independently associated with performance status of 0 (adjusted hazard ratio aHR 0.42, 95% confidence interval CI 0.23–0.75), platinum-free interval (PFI) of ≥ 6 months (aHR 0.46, 95% CI 0.28–0.78), histology of grade 1–2 endometrioid carcinoma (aHR 0.52, 95% CI 0.30–0.91), and relative dose intensity during the initial 8 weeks (8w-RDI) of lenvatinib of ≥ 50% (aHR 0.53, 95% CI 0.31–0.91). Patients with PFI of ≥ 6 months also demonstrated improved overall survival (HR 0.44, 95% CI 0.25–0.76) and objective response rate (44.0% versus 20.0%, P = 0.011) compared with those with PFI of < 6 months. Additionally, 8w-RDI of lenvatinib ≥ 50% was associated with improved overall survival (HR 0.53, 95% CI 0.30–0.92) compared to those with < 50%. Conclusions This study identified several novel prognostic factors for LP therapy. Among them, PFI may inform treatment selection for recurrent endometrial cancer following chemotherapy. Clinical trial registration University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR) 000049997.