Introduction/Background Nearly half of women diagnosed with endometrial cancer (EC) are 70 years old or older. Furthermore, elderly patients (>65 years) have been at risk for adverse perioperative outcomes throughout various surgical procedures and have a poorer prognosis which is related to both aggressive disease and under-treatment. We aimed to compare surgical and oncological outcomes between elderly (>65 year-old), intermediate to high risk, endometrial cancer patients undergoing staging with sentinel lymph node (SLN) staging and pelvic lymphadenectomy (LND).

Methodology A prospective cohort study of elderly patients diagnosed with endometrial carcinoma between 2007 and 2017, treated in a single center in Montreal, comparing surgical and oncological outcomes of 3 endometrial cancer patients cohorts in non-overlapping eras, undergoing surgical staging including: LND, LND+SLN or SLN. 2-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.

Results Out of 278 patients with a median age of 73 (65–91) years, that were staged and met the study inclusion criteria, 84 patients underwent LND only, 120 underwent SLN followed by LND and 74 patients had only SLN. Patients in the SLN group had significantly less dissected nodes (mean of 5.4 nodes vs 10.4 and 10.0 in the SLN+LND and the LND cohorts, respectively, p<0.001), shorter surgeries with a median time of 199 minutes (range, 75–393) compared to 231 (range, 125–403) and 229 (range, 151–440) minutes in the SLN+LND and LND cohorts, respectively (p<0.001) and minimal estimated blood loss with a median estimated blood loss of 20 ml (5–150) vs. 25 ml (5–800]) and 40(5–400) in the SLN+LND and LND cohorts, respectively (p=0.002). 42.4%, 19.8% and 36.2% of the all cohort received vaginal brachytherapy, external beam radiation and chemotherapy, respectively, with significantly more patients in the SLN group receiving brachytherapy (54.1% vs 41.7% and 33.3% in the SLN+LND and LND cohorts, respectively, p=0.03). 2-year overall survival and progression free survival were not significantly different between the 3 groups (p=0.45, p=0.51, respectively). On multivariable analysis, adjusted factors that were statistically significant on univariable analysis (age, ASA score, stage, grade, LVSI), adding SLN was associated with better OS, (HR 0.2, CI [0.1–0.6], P=0.006) and PFS (HR 0.5, CI [0.1–1.0], P=0.05).

Conclusion SLN based surgical staging is feasible, precise, affects adjuvant treatment and associated with better surgical and oncological outcomes in intermediate and high risk elderly patients.

Disclosures We have no disclosures.