Abstract
OBJECTIVE: This study aimed to assess the comparative effectiveness of indocyanine green and methylene blue in the marking and identification of sentinel lymph nodes during sentinel lymph node biopsy procedures in patients diagnosed with endometrial cancer undergoing staging surgery through vaginal natural-orifice transluminal endoscopic surgery. METHODS: In this retrospective cohort study conducted at a tertiary center, we analyzed 80 patients with endometrial cancer who underwent vaginal natural orifice transluminal endoscopic staging surgery. Patients were classified into two cohorts based on the tracer used for sentinel lymph node sentinel lymph node mapping: indocyanine green (n = 40) or methylene blue (n = 40). The primary endpoints, including sentinel lymph node detection rates (overall and bilateral) and number of nodes retrieved, along with surgical outcomes, were compared between the groups. FINDINGS: Eighty patients (indocyanine green group, n = 40; methylene blue group, n = 40) were included in the study. The vaginal natural orifice transluminal endoscopic surgery identification rate was significantly higher in the indocyanine green group (95%) than in the methylene blue group (82.5%) (p = 0.045). The mean number of sentinel lymph nodes identified in the indocyanine green group (3.2 ± 1.1) was significantly higher than that in the methylene blue group (2.5 ± 0.9) (p = 0.021). The rate of bilateral vaginal natural orifice transluminal endoscopic surgery identification was higher in the indocyanine green group (80%) than in the methylene blue group (65%); however, the difference was not statistically significant (p = 0.112). Surgical time, blood loss, and complication rates were similar between the two groups. Histopathological examination revealed a similar number of positive sentinel lymph nodes in both the groups. CONCLUSION: In the context of sentinel lymph node biopsy for staging surgery and natural orifice transluminal endoscopic surgery for endometrial cancer, indocyanine green has demonstrated a superior sentinel lymph node identification rate and a higher yield of sentinel lymph nodes compared to methylene blue. Given the advantage of real-time imaging, indocyanine green has emerged as a promising agent for sentinel lymph node biopsy in minimally invasive approaches, such as vaginal natural orifice transluminal endoscopic surgery.