Surgical and oncological outcomes of sentinel lymph node sampling in elderly patients with intermediate to high-risk endometrial carcinoma (547)

Abstract

<b>Objectives:</b> To evaluate the surgical and oncological outcomes of elderly patients with intermediate to high-risk endometrial cancer (EC) undergoing staging with sentinel lymph node (SLN) sampling and pelvic lymphadenectomy (LND). <b>Methods:</b> A retrospective study was conducted among all elderly (>65-year-old) patients diagnosed with EC between 2007 and 2017 and treated in a single center in Montreal, Canada. We compared the surgical and oncological outcomes of three cohorts undergoing surgical staging in non-overlapping eras: 1) LND, 2) LND and SLN, 3) SLN. Two-year progression-free survival (PFS), overall survival (OS), and disease-specific survival (DSS) were analyzed using life tables, Kaplan-Meier survival curves, and log-rank tests. Odds ratios (OR) and hazard ratios (HR) and their respective 95% confidence intervals (95% CI) were calculated using multivariable logistic regression and Cox proportional hazard models. <b>Results:</b> The study included 278 consecutive patients with a median age of 73 (65-91) years; 84 underwent LND, 120 underwent SLN with LND, and 74 had SLN alone. The SLN group had significantly more grade 2/3 disease (89.2% vs 72.5% and 70.2% in the SLN with LND and the LND groups, respectively, p=0.008) and a trend towards a higher rate of positive nodes (23% vs 14.2% and 14.3% in the SLN with LND and the LND groups, respectively, p=0.22). The SLN group had a shorter total operative time with a median duration of 199 minutes (range: 75-393) compared to 231 (range: 125-403) and 229 (range: 151-440) minutes in the SLN with LND and LND cohorts, respectively (p<0.001), as well as lower, estimated blood loss with a median loss of 20ml (5-150) versus 25ml (5-800) and 40ml (5-400) in the SLN with LND and LND cohorts, respectively (p=0.002). The 2-year OS and PFS were not significantly different between the three groups (p=0.45, p=0.51, respectively). On multivariable analysis after adjusting for age, ASA score, stage, grade, and LVSI, adding SLN was associated with better OS (HR: 0.2, 95% CI: 0.1-0.6, p=0.006), and PFS (HR: 0.5, 95% CI: 0.1-1.0, p=0.05). <b>Conclusions:</b> SLN based surgical staging is feasible and associated with better surgical and oncological outcomes in elderly patients with intermediate and high-risk EC.