Introduction/Background Standard surgical management for borderline ovarian tumours (BOT) is the complete tumour resection with adequate surgical staging including peritoneal biopsies, cytology and, at least, infracolic omentectomy but there is increasing evidence that completion of staging procedures (COS) do not reduce the risk of recurrence or increases overall survival. Our aim is to explore the role of completion of staging in BOT focused on oncological outcomes and peri-operative safety.

Methodology All patients with histologically confirmed diagnosis of BOT referred to the Northern Gynaecological Oncology Centre from December 2012 to December 2022, were included in the study. Clinico-pathological and demographic data were collated alongside detailed follow-up in conjunction with primary care.

Results From 2012 to 2022 (10 years) 180 patients were discussed in NGOC MDT with diagnosis BOT. 83 (46%) had serous and 97 (54%) mucinous or sero-mucinous histology. 97% were diagnosed with FIGO stage I disease and 61% had normal tumour markers on presentation. 94 (52%) patients proceeded with COS with very low Clavien-Dindo peri-operative complication rate ( grade 2: 4%, grade 3: 1%). 2 patients diagnosed and 1 died with ovarian cancer during the follow up period. There was no statistical significant difference in recurrence rate (p= 0.375) and survival ( p= 0.181) between patients with or without COS. In the cohort of patients with serous borderline tumours, 46/83 (55%) underwent COS and 9 of them (9/46, 20%) had residual disease in the final histology ( 8 borderline, 1 ovarian malignancy). No deaths or recurrences noted for this cohort. Despite this high rate of residual disease, the survival and the recurrence rate was similar comparing to the 37 patients (45%) who had no COS.

Conclusion COS is a safe procedure with low rate for peri-operative complications but does not reduce the recurrence rate or increases survival.

Disclosures Authors have no conflict of interest to declare