Neoadjuvant Chemotherapy Followed by Interval Debulking for Advanced-Stage Endometrial Cancer: Survival Outcome Based on Surgical and Molecular Characteristics.

OBJECTIVE: To examine survival outcomes and identify clinicopathological factors associated with survival in patients with advanced-stage endometrial cancer who received neoadjuvant chemotherapy before interval debulking surgery (NACT-IDS). METHODS: A single-center retrospective cohort study was conducted of patients who were diagnosed with advanced-stage (2009 FIGO IIIB, IIIC, IV) endometrial cancer (2012-2024) and underwent NACT-IDS. Tumor response to NACT was determined with computed tomography and the RECIST criteria, and demographic, clinicopathologic, perioperative, and tumor molecular features (mismatch repair protein [MMR] status and p53 pattern) were collected from medical chart review. Association between tumor molecular features and response to NACT was determined. Primary endpoints were progression-free and overall survival, analyzed with univariate Cox and stratified Kaplan-Meier analysis. RESULTS: Of 42 consecutive patients (median age of 68 years), the majority (n = 26; 61.9%) had a partial tumor response to NACT, with only five (11.9%) having a complete response, four (9.5%) having stable disease, and seven (16.7%) having progressive disease. Most cases had no residual tumor after IDS (n = 35; 83.3%). MMR protein status was associated with the tumor response to NACT (p = 0.013), but p53 status was not. During follow-up, 24 patients died (57.1%), and 31 (73.8%) died or had disease progression. Tumor response to NACT and resection margin status were associated with progression-free survival in unadjusted analyses, but no covariate adjustment was possible with limited sample size. CONCLUSIONS: This study highlights MMR-deficiency, response to NACT, and surgical resection status as clinicopathologic features of interest for future studies of prognostic factors and alternative therapies in advanced-stage endometrial cancer.