Response to tamoxifen treatment and affecting factors in adolescents with pubertal gynecomastia

pubertal gynecomastia is the growth of benign glandular tissue in the breast in male adolescents. Although it spontaneously regresses, tamoxifen treatment is prescribed in selected cases. In this study, we aimed to evaluate the initial symptoms, clinical and laboratory findings, side effects of and responses to tamoxifen treatment, and affecting factors in adolescents with pubertal gynecomastia. Between 2006 and 2018, 83 adolescents with pubertal gynecomastia who treated with tamoxifen were evaluated retrospectively from the archive and the electronic medical records. Response to tamoxifen treatment was good in 93.7% of adolescents and no significant changes were found in the liver transaminases, leukocyte and platelet counts. At the initiation of the treatment, 70.9% of adolescents were in Tanner stage 3 or 4 and the rate of complete resolution the gynecomastia disc was higher in adolescents with Tanner stage 5. In the adolescents with the initial disc diameters equal to or greater than 3 cm.s, the reduction in disc diameter compared to the initial diameter for each month was significantly higher than in the ones with the initial dimeters lower than 3 cm.s. The diameters of gynecomastia discs in adolescents showed significant reduction with the fourth, fifth and sixth months of tamoxifen treatment. In conclusion, as previously reported from our clinic, tamoxifen treatment in pubertal gynecomastia has been shown to be effective and safe. However, the fact that the number of cases was higher and more adequate in this study, allowed for more detailed analyzes that was not possible in our previous studies. In the literature, the duration of tamoxifen treatment was recommended as 4-6 months, but with this study, it was determined that the treatment should be continued for 6 months in order to achieve optimal effect. In addition, it is recommended that the disc diameter size accepted as an indication for tamoxifen treatment should be 3 cm instead of 4 cm.