Prostate cancer is becoming more and more prevalent in clinical practice Regarding endocrine therapy for prostate cancer, there is a new approach, but its not yet supported by bulk clinical evidence, called intermittent endocrine therapy. IHT is proposed 1) IHT means PSA 4ng/ml after a period of endocrine therapy by CaP. 2. PSA rises to 10-20ng/ml. 3. PSA rises to 20ng/ml. 4. PSA rises, to 1/2 of the pre-treatment value. 5. *For those who have 80% decrease in PSA without reaching normal value, when PSA rises by 20% of the lowest value. Implications of IHT treatment 1. May maintain the hormone dependence of prostate cancer cells 2. May delay the progression of prostate cancer cells to non-hormone dependence 3. May prolong the survival of patients. Potential risks of IHT treatment 1: Accelerates the progression of tumor hormone dependence to non-dependence 2: Lesions may develop in the interval of treatment