Gonadotropin-releasing hormone (GnRH) agonists decrease bone mineral density (BMD) and increase fracture risk in men with prostate carcinoma. GnRH agonists also increase fat mass and decrease lean body mass. These treatment-related changes in body composition may contribute to fatigue, emotional distress, and decreased quality of life. Whereas the consequences of initial GnRH agonist on BMD and body composition are well characterized, less is known regarding the effects of GnRH antagonists. At the best of our knowledge the changes in body composition induced by Degarelix in prostate cancer patients has never been explored. Dual-energy X-ray absorptiometry (DXA) is a reliable and accurate method to determine the changes in body composition in patients with prostate cancer (PCa) undergoing androgen deprivation therapy (ADT).