Prostate cancer is the most common cancer for men in Europe and it is in the first place for incidence in Italy. In almost all cases occur in men over 70 years old with a 5 years overall survival of approximately 88%. Prostate cancer is a multifactorial disease and it is the result of a complex interaction of genetic and environmental factors. Today newer forms of androgen-deprivation therapies remain the first line treatment for this disease. Currently androgen deprivation can be achieved through several mechanisms: surgically (bilateral orchiectomy) or medically (GnRH agonists and antagonists, anti-androgens or estrogens). Advanced age and the presence of biologically active androgens, in the circulating blood and prostate tissue, represent the most important causal factors related to the tumour. The medical treatment represents the standard of care and GnRH agonists and antagonists are the first choice of treatment in both phases of the natural history of tumor (locally advanced and metastatic setting) with continuously or intermittent modality. Osteoporosis, loss of erectile function, gynecomastia, and metabolic syndrome are some of typical side effects of androgen deprivation therapy. Unfortunately, due to prostate cancer heterogeneity, in most cases, despite an excellent initial response, the tumour will progress through treatment to a hormone refractory (HRPC), androgen independent (AIPC), or castration resistant prostate cancer (CRPC) stage. The use of GnRH analogues may contribute to the control of tumour growth and maintenance of the castrate state is an essential component in the treatment of patients who progress while on hormonal therapy. Current national and international guidelines recommend continuing with androgen deprivation, LHRH analogues, in association with subsequent treatments (chemotherapy and next generation hormonal-therapies).