The efficacy and safety of lenvatinib plus pembrolizumab therapy in patients with uterine carcinosarcoma

Lenvatinib plus pembrolizumab (LP) therapy is currently used in patients with advanced or recurrent endometrial cancer. However, patients with uterine carcinosarcoma (UCS) were not included in the KEYNOTE-775, and the efficacy of LP therapy for patients with UCS in clinical practice remains unclear. We administered LP therapy to five patients with UCS. We aimed to report our clinical experience with LP therapy in these patients and investigate the genomic characteristics of those who responded to LP therapy. We retrospectively reviewed patients with UCS (n = 5) who underwent LP therapy at our hospital from January 2019 to December 2023. Efficacy was assessed using the response rate according to the Response Evaluation Criteria in Solid Tumors version 1.1. Safety was evaluated in terms of adverse events. The median age was 65 (55–78) years, and the mismatch repair status was proficient in all of the patients. One patient had stage II disease, and four had stage III. The median number of LP therapy courses was 8 (1–35). The overall response rate was 40%. None of the patients experienced adverse events that were grade 3 or higher. The median follow-up duration was 9 (1–26) months, median progression-free survival was 9.1 (0.16 to NA) months, and median overall survival was 10.2 (1.41 to NA) months. LP therapy may be effective for patients with UCS. As this report was based on a limited number of patients, more cases are required to investigate the efficacy of LP therapy in patients with UCS.