Factors associated with successful bilateral sentinel lymph node mapping in endometrial cancer

• SLN mapping for endometrial cancer has a high rate of failed bilateral mapping.
• BMI, isosulfan blue dye use, and enlarged nodes are associated with failed mapping.
• Patients with BMI ≥ 30 should have SLN mapping performed with indocyanine green dye.

ObjectiveAs our understanding of sentinel lymph node (SLN) mapping for endometrial cancer (EC) evolves, tailoring the technique to individual patients at high risk for failed mapping may result in a higher rate of successful bilateral mapping (SBM). The study objective is to identify patient, tumor, and surgeon factors associated with successful SBM in patients with EC and complex atypical hyperplasia (CAH).MethodsFrom September 2012 to November 2014, women with EC or CAH underwent SLN mapping via cervical injection followed by robot-assisted total laparoscopic hysterectomy (RA-TLH) at a tertiary care academic center. Completion lymphadenectomy and ultrastaging were performed according to an institutional protocol. Patient demographics, tumor and surgeon/intraoperative variables were prospectively collected and analyzed. Univariate and multivariate analyses were performed evaluating factors known or hypothesized to impact the rate of successful lymphatic mapping.ResultsRA-TLH and SLN mapping was performed in 111 women; 93 had EC and 18 had CAH. Eighty women had low grade and 31 had high grade disease. Overall, at least one SLN was identified in 85.6% of patients with SBM in 62.2% of patients. Dye choice (indocyanine green versus isosulfan blue), odds ratio (OR: 4.5), body mass index (OR: 0.95), and clinically enlarged lymph nodes (OR: 0.24) were associated with SBM rate on multivariate analyses. The use of indocyanine green dye was particularly beneficial in patients with a body mass index greater than 30.ConclusionInjection dye, BMI, and clinically enlarged lymph nodes are important considerations when performing sentinel lymph node mapping for EC.