Learning Curve and Detection Accuracy of Sentinel Lymph Node Biopsy for Endometrial Cancer Staging: Experience from an ESGO & GESEA Certified Center

Background/Objectives: Pelvic lymphadenectomy has long been considered the gold standard for surgical staging in early-stage endometrial cancer. However, sentinel lymph node biopsy (SLNB) with ultrastaging has emerged as a less invasive alternative. The aim of the study is to assess the detection rate, learning curve and diagnostic accuracy of SLNB in a cohort of patients with a high prevalence of obesity and early-stage endometrial cancer. Methods: This relatively small prospective single-center study included patients with presumed early-stage endometrial carcinoma who underwent laparoscopic hysterectomy, SLNB and bilateral pelvic lymphadenectomy at the 1st Department of Obstetrics & Gynecology between 1 April 2023 and 31 May 2025. Results: Forty-one patients were recruited. The mean age was 64.3 years, and the mean BMI was 32.4 kg/m2. Bilateral and overall sentinel lymph node (SLN) detection was achieved in 27 of 41 patients (65.9%) and 85.4%, respectively. Concerning the learning curve, after the first 20 cases the bilateral detection rate was as high as 90.5% (p-value < 0.001). The median number of SLN for the left and right side were 1 (IQR: 1–2) and 2 (IQR: 1–3), respectively. The median number of lymph nodes dissected by lymphadenectomy was 7 (IQR: 5–8) for both sides. There were three patients with lymph node metastases, all of which were detected by SLNB. Conclusions: Bilateral detection of SLNs is technically feasible and requires a relatively short learning curve, under expert supervision in a high-volume, standardized training environment, even in patients with a high prevalence of obesity. The adoption of a standardized detection protocol is key to avoiding mapping failure.