Green versus blue: Randomized controlled trial comparing indocyanine green with methylene blue for sentinel lymph...

To ascertain the increase in detection rate of sentinel lymph node (SLN) associated with the use of indocyanine green (ICG) in comparison with methylene blue dye in women with endometrial cancer.

For this randomized controlled trial, all patients underwent SLN mapping after injection of blue dye on one side of the cervix and ICG on the other side. Randomization was for the side (right vs. left) on which ICG was used so that each patient's contralateral hemipelvis (HP) served as a control to her ipsilateral HP. We performed a two-tailed, normal-approximate McNemar test for paired-matched data. The primary endpoint was the difference in SLN detection rate for each HP according to the dye used.

This trial included 132 patients, and 46 patients underwent robotic-assisted surgery while 86 had standard laparoscopic surgery. Successful detection of SLN was 90.9% using ICG and 64.4% using blue dye (p < 0.0001). There were no differences in the duration of the SLN procedure (median 10 min per HP) and number of SLN per HP (mean 1.2) according to the dye used. The SLN detection rates for either dye were very similar whether the surgical approach was robotic (mean BMI 45) or laparoscopic (mean BMI 29). Crossover of dye to the contralateral HP was present in 3% of cases.

The use of ICG instead of blue dye results in a 26.5% (95% CI 17.4%-35.6%) increase of SLN detection rates per HP in women with endometrial cancer.