Survival outcomes, treatment response, and prognostic factors of different treatment modalities in patients with epithelial ovarian cancer: a retrospective cohort study.

Epithelial ovarian cancer (EOC) is commonly diagnosed at an advanced stage; however, the optimal upfront treatment - primary debulking surgery (PDS) versus neoadjuvant chemotherapy followed by interval debulking surgery (NACT+IDS) - remains controversial. This single-center retrospective cohort study used propensity score matching (PSM) to compare overall survival (OS), progression-free survival (PFS), surgical outcomes, tumor response, and safety between PDS and NACT+IDS in 197 EOC patients treated between March 2022 and April 2024, with follow-up censored in April 2026. After 1:1 PSM, 80 matched pairs were analyzed. Compared with the PDS group, the NACT+IDS group demonstrated significantly shorter operative time, less blood loss, a higher R0 resection rate, fewer ICU admissions, and a lower incidence of severe complications within 30 days after surgery (all P<0.05). The NACT+IDS group also had higher overall response and disease control rates (both P<0.05), whereas the incidence of grade ≥3 chemotherapy-related adverse events was comparable between groups (P=0.500). PFS and OS did not differ significantly between the two cohorts (P=0.795 and P=0.062, respectively), and treatment modality was not independently associated with either endpoint in multivariable Cox regression analyses. Poor tumor differentiation and residual lesion >1 cm were independently associated with shorter PFS, whereas FIGO stage IV disease, poor tumor differentiation, and residual lesion >1 cm were independently associated with shorter OS. Subgroup analyses suggested potential differences according to histological subtype; however, these findings were exploratory due to limited sample size. In conclusion, PDS and NACT+IDS offer comparable survival outcomes in patients with advanced EOC, whereas NACT+IDS is associated with improved perioperative safety and higher tumor response rates without increasing severe chemotherapy-related toxicity. Treatment decisions should be individualized according to tumor biology, resectability, and patient characteristics rather than based on a uniform treatment strategy. These findings warrant confirmation in larger prospective studies.