Relevance of sentinel lymph node procedure for patients with high-risk endometrial cancer

Objective. While the accuracy of the Sentinel Lymph Node (SLN) procedure has been validated in patients with early-stage endometrial cancer (EC) at low and intermediate risk of recurrence, its relevance for high-risk EC remains unknown. The aim of this study was to evaluate the contribution of SLN biopsy in staging patients with presumed high-risk EC. Methods. This retrospective multicenter study, conducted from January 2001 to December 2012, included 180 patients with early-stage EC undergoing SLN biopsy. Detection rate and false negative rate were assessed according to risk groups of recurrence. Results. SLNs were detected in 159/180 patients (88%) and were bilateral in 63% of cases. Of the 180 patients, 41(22%) had a positive lymph node. Ultrastaging detected metastases undiagnosed by conventional histology in 17/41 patients (41%). The false negative rate was 6% (9/159); 2.3% in the low/intermediate risk group and 20% in the high-risk group (p = 0.0008). Lymphovascular space invasion (LVSI) was present in 48 patients (27%). Preoperative findings classified 146 patients as ESMO low/intermediate risk (81%) and 34 as high risk (19%). Ten of the 34 patients (29%) in the presumed high-risk group were downstaged on final histology and 5/18 patients (28%) initially diagnosed with type 2 were finally classified as having type 1 EC. Classification was more likely discordant for patients with preoperative type 2 EC (p = 0.03) and in the initial high-risk group (p = 0.02). Conclusions. SLN biopsy associated with LVSI status can select which high-risk patients with EC would benefit from comprehensive staging. (C) 2014 Published by Elsevier Inc.