Retrospective review of sentinel lymph node mapping in endometrial cancer using indocyanine green and near infra-red fluorescence imaging during minimally invasive surgery

Objectives: To determine the feasibility of sentinel lymph node (SLN) mapping in early-stage endometrial cancer and to evaluate the impact of the SLN result on adjuvant therapy prescription. Materials and methods: 140 women with histologically confirmed endometrial cancer, treated with a minimally invasive hysterectomy, bilateral salpingo-oophorectomy and SLN mapping were included. All mapped SLNs were confirmed by histopathology. Where the SLN was negative on H&E staining, ultra-staging with IHC was performed. Results: From January 2017 to May 2019, 122 patients were analysed. The overall and bilateral SLN detection rates were 86% (105/122) and 73% (89/122), respectively. The detection rates were not significantly different between low and high-risk disease. SLN metastasis was found in 15% (3/20) of patients the in high-risk group and 5.7% (5/87) in the low-risk group. Six of the 8 cases were identified by ultra-staging. Fourteen of 103 patients had their adjuvant treatment reduced based on SLN status after ultra-staging. Conclusion: SLN mapping can reliably detect the SLN in low and high-risk disease. The advantage for SLN mapping is in low-risk patients that allowed them to receive appropriate adjuvant therapy. Ultra-staging with IHC increased the detection of positive SLNs and decreased the prescribed adjuvant therapy in 14% of our patients.