Long-term adjuvant androgen deprivation therapy (ADT) is the current standard systemic management associated with high-dose radiotherapy (HRT) for the treatment of localized high-risk prostate cancer (PCa). The regulatory authorities have traditionally set target testosterone levels during ADT at <50 ng/dL. However, recent data suggest that additional serum TT suppression <20 ng/dL can improve clinical outcomes in non-metastatic PCa, though the available information is scant and mostly comes from analysis performed in advanced and metastatic disease. The other crucial point in patients treated with long-term (2-3 years) ADT is to what extent does sustainment of castrate TT levels after discontinuation of ADT affect not only adverse long-term effects but biochemical control rates.