Single center, prospective phase II trial.
Carcinosarcoma is a malignant neoplasm that is composed of both epithelial and mesenchymal elements and aggressive tumor that are staged as high-grade cancer in NCCN guideline. They are regarded as rare aggressive malignancies with a high potential to develop distant metastases and are associated with an overall poor survival. The aggressive nature of this malignancy coupled with a high relapse rate defines a poor clinical course for most patients. First line treatment of patients with advanced uterine carcinosarcoma with paclitaxel plus carboplatin achieved an objective response rate of 54% of patients. For this orphan tumor, carcinosarcoma, as these drugs would hypothetically act only on tissues with overexpression of PD-L1, they theoretically provide a more precise therapeutic effect on tumor cells with considerably less side effects. Therefore, the investigators suggest phase II trial of nivolumab for metastatic/recurred carcinosarcoma who have progressed after prior chemotherapy.