Strengths
These figures are on par, if not better than those reported in the literature. Two meta-analysis performed by Smith et al. and Kang et al. on endometrial cancer SLN mapping reported a unilateral pooled average detection rate of 78-81% with a bilateral detection rate of 61% [2, 5]. Although single institution data is difficult to compare to a meta-analysis, this finding supports that our results are comparable to those at other institutions.
Guidelines extrapolated from studies of breast cancer, melanoma and vulvar cancer suggest that surgeons need to complete 30 cases in order to achieve competency for the reliable detection of SLN in endometrial cancer staging procedures [6]. Following recommendations from the American Society of Clinical Oncology (ASCO) on acceptable proficiency for breast cancer SLN mapping, the metastatic detection rate should be greater than 80-90% and the false negative rate should be less than 5%. [7]. In our cohort, the rates of successful SLN mapping improved over the course of our study period. This reflects increased provider detection rates over time with improvement of surgical skill. With regards to false negative rates, our data performed well with disease detected in only three non-SLN. All three patients had serous components to their tumors, and received adjuvant treatment with chemotherapy and radiation. To date, there have been no disease recurrences in this cohort over a median follow up of 22 months.