 The patients were 14 transgender girls with a mean age of 15.8 years (range 12 to 18.4 years) who were treated with 50 mg/day bicalutamide between 2013 and 2017, of whom 7 returned for follow-up.In addition to showing effectiveness as an antiandrogen in the individuals, bicalutamide monotherapy increased estradiol levels and promoted feminization as a secondary effect.This included breast development to Tanner stage 2 and 3 in 86% of the patients after an average of 5.7 months of treatment, with the seventh girl showing Tanner stage 3 breast development at her second follow-up at 12.5 months.