Objective  To compare the application value of indocyanine green (ICG), nano-carbon, methylene blue (MB) tracing methods, and ICG combined with nano-carbon tracing method in laparoscopic surgery for stage Ⅰ to Ⅱ endometrial cancer according to International Federation of Gynecology and Obstetrics (FIGO) staging system.

Methods  A retrospective selection of 92 patients who underwent laparoscopic surgery for stage Ⅰ to Ⅱ endometrial cancer was conducted. Based on intraoperative sentinel lymph node (SLN)tracing method, the patients were divided into ICG group (n=24, using ICG tracing method), nano-carbon group (n=22, using nano-carbon tracing method), MB group (n=23, using MB tracing method), and combined group (n=23, using ICG combined with nano-carbon tracing method). Surgical-related indicators, pathological results, and the incidence of complications were compared among the four groups. The detection efficacy of different tracing methods was also compared, using pathological results of surgical specimens as the gold standard.

Results  There were no statistically significant differences in the SLN resection time, total operative time, and intraoperative blood loss among the four groups (P>0.05). The number of lymph nodes resected intraoperatively in the combined group was significantly higher than that in the other three groups (P < 0.05). There were no statistically significant differences in the pathological results of surgical specimens (tumor invasion depth>50%, tumor diameter>2 cm, tumor invasion of the cervix or lymphovascular space) among four groups (P>0.05). The complication rates in the ICG group, nano-carbon group, MB group, and combined group were 4.17%, 9.09%, 8.70%, and 13.04%, respectively, with no statistically significant difference (P>0.05). Using the pathological results of surgical specimens as the gold standard, the detection accuracy, sensitivity, and specificity of ICG combined with nano-carbon tracing method for SLNs in patients with stage Ⅰ to Ⅱ endometrial cancer were 86.96%, 90.00%, and 66.67%, respectively. The positive predictive value and negative predictive value were 94.74% and 50.00%, respectively. The detection efficacy of this combined method was higher than that of the other three methods.

Conclusion  Compared with the ICG, nano-carbon, and MB tracing method, ICG combined with nano-carbon tracing method has a higher application value in laparoscopic surgery for stage Ⅰ toⅡ endometrial cancer. It can accurately identify the status of lymph node metastasis, with a moderate price and simple operation.