Int J Gynecol Cancer. 2026 Jul 11:104869. doi: 10.1016/j.ijgc.2026.104869. Online ahead of print.
ABSTRACT
OBJECTIVE: To evaluate the association between exposure to pembrolizumab-based therapy in the post-platinum setting and survival outcomes in patients with metastatic or recurrent uterine carcinosarcoma.
METHODS: In this retrospective study, patients with metastatic or recurrent uterine carcinosarcoma treated at three tertiary centers between January 2008 and April 2025 were included. Patients received various treatment modalities after recurrence or progression in the post-platinum setting. Survival outcomes were analyzed according to whether patients were exposed to pembrolizumab-based therapy after recurrence or progression. Survival after recurrence and overall survival were evaluated using Kaplan-Meier analyses and Cox proportional hazards models. Additional analyses using inverse probability of treatment weighting, doubly robust methods, and time-dependent Cox models were performed.
RESULTS: A total of 147 patients were included, of whom 42 (28.6%) received pembrolizumab-based therapy in the post-platinum setting. In multi-variable analyses, pembrolizumab-based therapy exposure was independently associated with improved survival after recurrence (hazard ratio 0.44, 95% confidence interval 0.24 to 0.83, p = .01) and overall survival (hazard ratio 0.48; 95% confidence interval 0.26 to 0.89, p =.02). Positive peritoneal washing cytology was independently associated with poorer survival outcomes. In time-dependent Cox analyses using inverse probability of treatment weighting, pembrolizumab-based therapy exposure remained significantly associated with improved survival after recurrence (hazard ratio 0.56, 95% confidence interval 0.33 to 0.96, p =.035), whereas the association with overall survival was no longer statistically significant.
CONCLUSIONS: Exposure to pembrolizumab-based therapy in the post-platinum setting was associated with improved survival after recurrence in patients with metastatic or recurrent uterine carcinosarcoma. These findings support the potential clinical relevance of pembrolizumab-based therapy in the post-platinum setting and warrant further prospective validation.
PMID:42613237 | DOI:10.1016/j.ijgc.2026.104869
