Epithelial ovarian cancer (EOC) is a highly aggressive malignancy, frequently diagnosed
at an advanced stage and requiring a combined approach of surgery and systemic therapy.
Complete cytoreductive surgery remains the most important prognostic factor, as residual
disease ≥1 cm significantly worsens survival. In November 2019, a regional decree in
Emilia-Romagna (Italy) introduced the centralization of EOC treatment to high-volume
centers to improve care quality and clinical outcomes.

Shortly thereafter, the onset of the COVID-19 pandemic led to a severe reduction in
healthcare resources, including surgical capacity, ICU beds, and staff availability. This
situation resulted in a higher proportion of patients being referred for neoadjuvant
chemotherapy, with surgery performed mainly in selected patients with better performance
status and higher chances of complete resection. During this period, an increase in
centralized treatments, multidisciplinary evaluations, BRCA testing, and use of interval
debulking surgery (IDS) was observed.

This observational, retrospective study is designed to evaluate whether centralization
and pandemic-related treatment modifications influenced oncological outcomes. The primary
objective is to compare progression-free survival (PFS) and overall survival (OS) among
patients treated during three different timeframes: pre-centralization/pre-pandemic
(2018-2019), peak pandemic phase (2020-2021), and pandemic control phase (2022-2023).
Secondary objectives include describing treatment strategies after initial diagnosis
(type of surgery, chemotherapy, maintenance therapies), tumor characteristics (histology,
BRCA/HRD status), recurrence patterns (site, symptoms, treatment), and the proportion of
patients receiving secondary surgery, radiotherapy, Bevacizumab, and/or PARP inhibitors.
No experimental interventions are included, and all patients received treatment according
to routine clinical practice.