Introduction Elderly women with ovarian cancer are often undertreated. We aimed to evaluate the treatment modalities of elderly patients and its impact on overall survival.

Methods A total of 5,055 high grade serous ovarian cancer patients and 3584 advanced stage (IIIC+IV) patients aged 65 years or older were hereby identified, all from the Surveillance, Epidemiology, and EndResults (SEER) database from January 1, 2010 to December 31, 2017. Overall survival (OS) and ovarian cancer-specific survival (OCSS)was compared across age and Cox proportional-hazards model was created to adjust for case-mix.

Results The very elderly patients (≥75 years old) had significantly: less surgical complexity like undone lymphadenectomy (59.7% vs 48.6%; p < 0.001), less chemotherapy (78.2% vs 89.4%; P<0.001), less standard treatment (70.6% vs. 85%; p < 0.001) and less optimal debulking surgery (44.0% vs 52.7%; p < 0.001). The very elderly and elderly patients all had a high use of NACT, but no significant difference was found (38.7% vs 36.2%; P=0.212). Patients ≥75 had significantly worse OS and OCSS.

Conclusion/Implications The survival of women with EOC strongly decreases with increasing age, EOC patients over 75 years old received less standard treatment and more elderly patients were treated with NACT.