Introduction The aim of this study was to evaluate the results of the sentinel lymph node (SLN) biopsy performed by doctors in training in a referral cancer center, from 2016 to 2020.

Methods 126 patients, over 18y.o., with a prior diagnosis of initial endometrial (EC) or cervical (CC) cancer underwent to SLN biopsy performed by surgical oncology residents or gynecologic oncology fellows, under direct supervision of a qualified preceptor. SLN was detected with blue dye with or without scintigraphy.

Results Patients underwent surgery by laparotomy - 22 surgeries (17.46%), by laparoscopy - 86 (81.13%) and by robotic - 18 (16.98%). SLN detection rate was 84.1% (n=106), bilateral in 53% (n=67) and mostly in younger patients (59.7% under 60y.o., p=0.022). There was a higher failure rate (non or unilateral detection) among older than 60y.o. (p=0.0075, CI:0.1656–0.7928, OR:0.3664). Among non-smokers, there was a greater bilateral detection of LNS (60.3%), and, among smokers, more cases of detection failure (59.4%). In 3 cases, the SLN was not identified, and there were positive pelvic nodes in the lymphadenectomy. There were no cases with positive nodes at lymphadenectomy with a negative SLN (false-negative). Four patients had grade 3 complications, and none died.

Conclusion We have demonstrated that residents and fellows can safely perform SLN biopsy for initial CC and EC under the direct supervision of a trained surgeon. Detection rates were aligned to the literature, and there were no false negatives. Lymph node positivity, age over 60y.o. and smoking were associated with a higher SLN non-detection rate.