Tamoxifen Treatment for Pubertal Gynecomastia: When to Start and How Long to Continue.

Introduction: Pubertal gynecomastia is a common clinical condition among male adolescents, and in most cases, it regresses spontaneously. However, tamoxifen treatment is recommended in selected cases. We aimed to evaluate the indications, safety, and efficacy of tamoxifen treatment in adolescents with pubertal gynecomastia. Methods: The data of 83 adolescents with pubertal gynecomastia who were treated with tamoxifen between 2006 and 2018 were evaluated retrospectively. The clinical and laboratory data, initial complaint, tamoxifen treatment indication, duration, and dose were recorded along with the treatment outcome. Results: The gynecomastia disc diameter's monthly reduction rate was significantly higher in adolescents with an initial disc diameter ≥3 cm. The significant reduction of the disc started after the fourth month of tamoxifen treatment and continued to significantly reduce, extending to the sixth month. Conclusion: Tamoxifen treatment in pubertal gynecomastia was found to be effective and safe. One of the current indications for tamoxifen treatment is having a disc size ≥4 cm, and the recommended treatment duration is 4-6 months. However, this study suggests that treatment should be continued for at least 6 months to achieve the optimal effect. In addition, we recommend that the disc diameter threshold for starting tamoxifen needs to be ≥3 cm.