Introduction/Background Approximately 10% of patients with intraoperative diagnosis of low risk Endometrial Cancer (EC) will suffer an upstage after the definitive histological evaluation of the piece of hysterectomy and bilateral adnexectomy, We aim to explore the results associated with the performance of pelvic and para-aortic lymphadenectomy as restaging these patients that will require a second surgery, and to compare those with and without Sentinel Node Biopsy (SNB) in the first procedure.

Methodology Retrospective cohort study involving 27 patients diagnosed with low-risk EC (ESMO-ESGO-ESTRO criteria) with surgical restaging due to upstage in the final histological result at the Hospital Universitario Donostia from April 2013 to September 2018. Surgical and oncological results were compared between patients who underwent hysterectomy and double adnexectomy without any additional procedure (SNB-) n=17 and those who also had a pelvic and aortic SNB (SNB+) n=10.The main outcome evaluated in the study was intraoperative complications. Secondary outcomes were mean operative time, length of hospital stay, number of nodes obtained, Progression-Free Survival (PFS) and Overall Survival (OS).

Results The median duration of restaging surgery was 240 minutes (Q25 - Q75: 180 – 300) in the SNB(-) group, and 300 (Q25 - Q75: 247.5 – 330) minutes in the SNB(+) group, this difference being statistically significant (one-side t-student test, p=0.0295). With regard to intraoperative complications, there were 17.65% vs 40% respectively, all of them vascular, this difference being not significant. There were no statistical differences in length of hospital stay and number of pelvic nodes obtained. PFS and OS in both groups were the same.

Conclusion Women with EC who require lymph node restaging due to upstage and have previously undergone sentinel lymph node biopsy have greater surgical difficulty with longer duration of the procedure. The risk of complications is increased.We advise against performing a second re-staging surgery in patients sentinel node biopsy.

Disclosures No disclosures.