Introduction/Background The results of the prospective randomized phase-III LION-trial failed to demonstrate a therapeutic benefit from LND in tumor-free operated advanced OC patients with macroscopically normal appearing LN. Patients were randomized intraoperatively with exclusion of those thought by the surgeon not to be fully operable or with suspicious/bulky LN by inspection or palpation. We wished to address the surgical and survival outcomes of this excluded group in a single center.

Methodology This is a monocentric analysis in a tertiary ESGO-accredited center of excellence for OC. A total of 202 patients were screened for the original study; 120 were excluded, and 82 included in the final LION analysis. Excluded cases were retrospectively analyzed according to the same endpoints (PFS and OS) of the LION-trial with a subsequent comparison analysis.

Results Overall, 195 patients were included in the present analysis. Rate of CR was with 45% significantly lower in the intraoperatively excluded patients vs the tumor-free operated patients of the original LION analysis. This had a significantly negative impact on OS and PFS. Only 60% of the screening failed patients had histologically positive LN in final pathology. There was no significant difference in PFS or OS between the tumor-free operated screening failed patients versus those randomized, regardless of their histological LN-status and whether an LND was performed.

Conclusion Our findings confirm the lack of therapeutic LND in advanced OC even in patients with suspicious LN. Non-tumor-free operated patients had worse outcome. We demonstrated that intraoperative LN evaluation by the surgeon is subjective and inaccurate.