Prospective study of sentinel lymph node mapping for endometrial cancer

Objective To evaluate sentinel lymph node ( SLN ) mapping for endometrial cancer, using radioisotope and indocyanine green ( ICG ) injections. Methods A prospective study was conducted between April 1, 2014, and December 27, 2017, among women with endometrial cancer, excluding those with suspected peritoneal dissemination and lymph node metastasis, at a University hospital in Kagoshima, Japan. Patients with low‐risk endometrial cancer underwent pelvic SLN mapping using uterine cervix radioisotope injections; intermediate/high‐risk patients underwent pelvic SLN with/without intraoperative para‐aortic SLN mapping with ICG subserosal injections. Primary endpoints were estimated detection rates, sensitivity, and negative predict values ( NPV ) of SLN mapping. Results Of 113 patients evaluated, comprehensive pelvic lymphadenectomy was performed after SLN detection in all patients; additional para‐aortic lymphadenectomy was performed in 38 (34%) patients. The detection rates for pelvic SLN (≥1), bilateral pelvic SLN , and para‐aortic SLN (≥1) were 96%, 80%, and 55%, respectively. Pelvic and para‐aortic lymph node metastasis were found in (10%) (12/113) and 18% (6/33) patients, respectively. Isolated para‐aortic lymph node metastasis was not observed. In pelvic SLN analysis, sensitivity was 91% and NPV was 99%. In para‐aortic SLN analysis, sensitivity and NPV were 100%. Conclusion SLN biopsy may be useful to avoid comprehensive pelvic lymphadenectomy in low‐risk patients. In high‐risk patients, SLN mapping revealed high detection rates, sensitivity, and NPV , including those for para‐aortic SLN .