Primary or Interval Debulking Surgery for Advanced Endometrial Cancer with Carcinosis: A Systematic Review and Individual Patient Data Meta-Analysis of Survival Outcomes

Objective: To compare the survival outcomes of primary debulking surgery and platinum-based adjuvant chemotherapy versus interval debulking surgery after platinum-based neoadjuvant chemotherapy in patients with stage IVb endometrial cancer and peritoneal carcinosis. Methods: The online search included the following data sources: PubMed, Scopus, WOS, and the Cochrane Library from 1990 to 2024 (PROSPERO registration code: CRD42023438602). A total of 3230 studies were identified, with the inclusion of 16. Individual patient data on survival outcomes, disease distribution, and residual tumors, as well as details of neoadjuvant chemotherapy and adjuvant treatment, were extracted. Results: A total of 285 patients were included: 197 (69%) underwent primary debulking surgery and 88 (31%) underwent interval debulking surgery. The pooled analysis revealed a median progression-free survival in the primary debulking surgery group of 18.0 months compared to 12.0 months in the interval debulking surgery group (p = 0.028; log-rank test), and a median overall survival of 30.92 months versus 28.73 months (p = 0.400; log-rank test). Among the 134 patients with available information on the residual tumor after primary debulking surgery or interval debulking surgery, 110 (82%) had no macroscopic residual tumor (residual tumor = 0). The median progression-free survival was 18.9 months in the residual tumor = 0 group compared to 6.19 months in the residual tumor > 0 group (p < 0.001; log-rank test); the median overall survival was 40.6 months versus 21 months (p = 0.028; log-rank test). Conclusions: These results indicate that primary debulking surgery should be considered the preferred treatment approach for advanced endometrial cancer with carcinosis, especially in carefully selected patients where complete cytoreduction is achievable. Further prospective studies are warranted to confirm these results and to establish standardized criteria for patient selection, incorporating molecular-integrated risk profiles for endometrial cancer.