Pathological complete response following systemic therapy with carboplatin–paclitaxel plus pembrolizumab for initially unresectable mismatch repair-deficient advanced endometrial cancer: two case reports

Background: Mismatch repair-deficient (dMMR) endometrial cancer is highly sensitive to immune checkpoint inhibition. Although pembrolizumab combined with carboplatin and paclitaxel is now a first-line standard treatment for advanced or recurrent dMMR endometrial cancer, there is limited evidence regarding the effectiveness of this treatment for initially unresectable cancer. Case presentation: -aortic, and left supraclavicular lymph nodes. After six cycles of systemic carboplatin-paclitaxel plus pembrolizumab therapy, cytoreductive surgery showed no residual viable carcinoma, confirming a pCR. Discussion: These cases demonstrate that chemo-immunotherapy can induce a pCR in advanced dMMR endometrial cancer and may deepen the treatment response. Conclusion: Initial carboplatin-paclitaxel plus pembrolizumab therapy may enable less invasive surgery. These findings support the investigation of less invasive approaches for dMMR endometrial cancer.