Optimal debulking surgery in patients with advanced uterine carcinosarcoma: A multi-institutional retrospective study from the Japanese Gynecologic Oncology Group.

5591 Background: The benefit of cytoreductive surgery for uterine carcinosarcoma (CS) is unknown. The objective of this study was to assess the impact of optimal debulking surgery on survival of advanced uterine CS patients. Methods: We performed a multi-institutional, retrospective study of women diagnosed with stage III–IV uterine CS between 2007 and 2012. Data were retrospectively obtained from medical records and included demographic, clinicopathologic, treatment, and outcome information. Optimal debulking surgery was defined as surgery resulting in a maximum residual tumor of less than 1 cm. The Kaplan-Meier method was used to calculate disease-free survival (DFS) and overall survival (OS), and the Cox regression model was used to examine the impact of selected factors on survival. Results: A total of 225 uterine CS patients (median age, 62 years) were identified including 136 (60%) patients with stage III disease and 89 (40%) patients with stage IV disease. Among them, 185 (82%) patients received th...