Sentinel lymph node mapping in patients with stage I endometrial carcinoma: a focus on bilateral mapping identification by comparing radiotracer Tc99m with blue dye versus indocyanine green fluorescent dye.

PURPOSE: The aim of this study was to compare technetium radiocolloid (Tc99m) + blue dye (BD) versus Indocyanine green (ICG) fluorescent dye in terms of the overall detection rate and bilateral sentinel lymph node (SLN) mapping in patients with endometrial carcinoma.
METHODS: Patients from five European centers with apparently confined clinical stage I endometrial cancer were reviewed. A comparison was made between women who received SLN mapping with pelvic and/or aortic lymphadenectomy (LND), and women who underwent SLN algorithm (SA), was also performed between the two groups.
RESULTS: Three hundred and forty-two (342) women were involved (147 in the Tc99m + BD group and 195 in the ICG group). The overall detection rate of SLN biopsy was 97.3% (143/147) for women in the Tc99m + BD group and 96.9% (189/195) for women in the ICG group (p = 0.547). The bilateral mapping rate for ICG was 84.1%-significantly higher with respect to the 73.5% obtained with Tc99m + BD (p = 0.007). No differences in overall sensitivity (OS) and overall false negative rate (FNR) were seen between LND and SA (p value = 0.311), whereas the negative predictive value (NPV) was in favor of SA group (p value = 0.030).
CONCLUSIONS: In this study, fluorescent mapping using ICG resulted equivalent to the standard combined radiocolloid and BD, but real-time SLN mapping achieves a higher bilateral detection rate. The added value that this fast emerging technology promises to give certainly warrants future studies to further consolidate the advantages there are over the standard technique.