Sentinel lymph node biopsy with carbon dye in endometrial cancer: a single center, prospective cohort study

Background Many agents have been used for the detection of sentinel lymph nodes in endometrial cancer. Carbon dye, which has a strong staining ability and high contrast due to its dark black color, identifies the lymph nodes efficiently. Our aim was to evaluate the safety and efficacy of carbon dye for the detection of sentinel lymph nodes in endometrial cancer. Methods We conducted a single-center, prospective, cohort study in 89 patients with early-stage endometrial cancer between September 2021 and August 2022. The procedure was performed under laparoscopy. Results The sensitivity and negative predictive value of the sentinel lymph node biopsy (SLNB) with carbon dye injection were 83.3% and 98.8%, respectively. Mapping identified at least one sentinel lymph node in 84 patients (94.4%) on one pelvic side and at least one sentinel lymph node in 73 patients (82.0%) on each pelvic side out of 89 patients. In addition, no carbon dye-associated allergic reaction was detected. Conclusion Carbon dye is a non-allergenic, inexpensive, and effective agent for SLNB with a satisfying sensitivity and a negative predictive value. In addition, both unilateral and bilateral detection rates were sufficient. Accordingly, carbon dye may be a promising tracer and a considerable option, particularly for low-income countries.