Utilization and Surgical Outcomes of Sentinel Lymph Node Biopsy for Endometrial Intraepithelial Neoplasia.

Objective: To describe the rate and surgical outcomes of sentinel lymph node (SLN) biopsy in patients with endometrial intraepithelial neoplasia (EIN).

Methods: We conducted a cohort study that used the prospective American College of Surgeons National Surgical Quality Improvement Program database. Women with EIN on postoperative pathology who underwent minimally invasive hysterectomy from 2012 to 2020 were included. The cohort was dichotomized based on the performance of SLN biopsy. Patients' characteristics, perioperative morbidity, and mortality were compared between patients who underwent SLN biopsy and those who did not. Postoperative complications were defined using the Clavien-Dindo classification system.

Results: Overall, 4,447 patients were included; of those, 586 (13.2%) underwent SLN biopsy. The proportion of SLN biopsy has increased steadily from 0.6% in 2012 to 26.1% in 2020 ( P <.001), with a rate of 16% increase per year. In a multivariable regression that included age, body mass index (BMI), and year of surgery, a more recent year of surgery was independently associated with an increased adjusted odds ratio of undergoing SLN biopsy (1.51, 95% CI, 1.43-1.59). The mean total operative time was longer in the SLN biopsy group (139.50±50.34 minutes vs 131.64±55.95 minutes, P =.001). The rate of any complication was 5.9% compared with 6.7%, the rate of major complications was 2.3% compared with 2.4%, and the rate of minor complications was 4.1% compared with 4.9% for no SLN biopsy and SLN biopsy, respectively. In a single complications analysis, the rate of venous thromboembolism was higher in the SLN biopsy group (four [0.7%] vs four [0.1%], P =.013). In a multivariable regression analysis adjusted for age, BMI, American Society of Anesthesiologists classification, uterus weight, and preoperative hematocrit, the performance of SLN biopsy was not associated with any complications, major complications, or minor complications.

Conclusion: The performance of SLN biopsy in EIN is increasing. Sentinel lymph node biopsy for EIN is associated with an increased risk of venous thromboembolism and a negligible increased surgical time.