Objective The aim of the study was to evaluate extrapelvic sentinel lymph nodes (SLNs) in clinical early-stage endometrial cancer patients with unmapped pelvic side(s) during fluorescent imaging-based sentinel mapping.

Materials and Methods Eligible patients underwent sentinel mapping using cervical injection of indocyanine green and near-infrared florescent imaging compatible endoscopic systems. Pelvic SLNs were identified and resected. If bilateral mapping was not achieved, upper lymph nodes areas including presacral, upper common iliac, and para-aortic caval regions were explored for any SLN. Systematic lymphadenectomy was performed after applying SLN algorithm steps.

Results In 24 of 101 patients, bilateral pelvic mapping was not achieved. Bilateral unmapping was seen in 4 of 24 and unilateral pelvic side mapping in 20 of 24 patients. There was no extrapelvic SLN among 4 cases with bilateral pelvic unmapping, whereas 8 (40%) of 20 patients with unilateral pelvic mapping had extrapelvic SLNs. Five of extrapelvic SLNs were in presacral, 2 in upper common iliac, and 1 in paracaval regions.

Conclusions Observing for extrapelvic SLNs in cases with unmapped pelvic side(s) could increase detection rate of SLN mapping in clinical early-stage endometrial cancer.