Introduction/Background Ovarian cancer (OC) usually presents at advanced stage. Complete cytoreduction has a major positive effect on survival and primary debulking surgery (PDS) remains the standard treatment for advanced OC patients. When complete cytoreduction is not feasible, neoadjuvant chemotherapy and interval debulking surgery (IDS) must be considered. We aimed to compare surgical outcomes and survival rates between advanced OC (AOC) patients undergoing IDS and those undergoing PDS.

Methodology This retrospective single-center observational study includes consecutive women undergoing either PDS or IDS for AOC between January 2018 and September 2023. Chi-square, Fisher’s exact, Student-T, or Mann-Whitney tests were used to compare surgical complications and perioperative outcomes between groups. Kaplan-Meier and log-rank tests were used to assess differences in overall (OS) and progression-free survival (PFS).

Results Of the 66 patients included, 32 underwent PDS and 34 underwent IDS. The IDS group had higher levels of Ca125 (747.5 vs.341.9) and Fagotti score (8 vs.2, p=0.004) at diagnosis. In the PDS group, operative time was longer (321.3 vs.223.8minutes, p<0.001), and blood loss higher (500 vs.200ml, p=0.009). Complete cytoreduction was achieved in 85.3% of patients in PDS and 87.5% in IDS (p=1.00). There were no differences in the rate of intra-operative (9.4% vs.11.8%) or severe (Clavien-Dindo III-V) post-operative complications (28.1% vs.23.5%). Patients in the IDS group needed parenteral nutrition less often (15.6% vs.47.1%, p=0.008), had drainages removed earlier (5 vs.11 days, p=0.009) and had a shorter hospital stay (7.5 vs.11 days, p=0.034). These differences had no impact on the interval between surgery and start of chemotherapy. There were no significant differences in OS (45.7 vs.48.9 months) or PFS (17.7 vs.25.2 months) between groups.

Conclusion IDS is a valid alternative to PDS in selected patients with advanced OC, with similar rates of complete resection, intra and postoperative complications, and no significant differences in OS or PFS.

Disclosures The authors have no conflicts of interest to declare.