Introduction/Background Borderline ovarian tumors mainly affect young women, their prognosis is favorable but recurrence can occur 20 years after treatment, therefore the challenges in the management of this pathology will be to avoid recurrence, but also preserve fertility.

Methodology This is a retrospective study of 17 cases of OBT, followed and treated at the Gynecology and Obstetrics C department of the Ibn Rochd University Hospital in Casablanca between January 2018 and February 2020 (period of 2 years).

Results the average age of our patients was 45 years, the increase in abdominal volume was the most frequent clinical sign at the time of diagnosis, 82% of patients had a clinically palpable abdominopelvic mass with a size which varied between 6cm and 24cm, this mass was clinically suspicious in 41% of patients. An exploratory laparotomy under general anesthesia was performed immediately in all patients and the treatment was radical in 59% of cases and conservative in 41%. Peritoneal staging was complete in In 94% of cases, in only one patient the staging was incomplete.

The average follow-up duration in our study was 29 months; 12% of patients presented a contralateral recurrence in the form of a new borderline tumor confirmed histologically. The patients who presented these recurrences were all initially treated by conservative surgery (unilateral adnexectomy). The evolution was favorable in the rest of the patients and no deaths were reported.

Conclusion In our work, carrying out complete peritoneal staging does not seem to change the prognosis of OBT, the occurrence of a recurrence was linked to several prognostic factors the main factor was the performance of conservative surgery and the other factors were: young age of onset, advanced FIGO stage, presence of invasive peritoneal implants and high initial rate of CA125.

Disclosures Nothing to disclose.