Prostate cancer is one of the most common malignant tumors in men. In most cases, it grows slowly under the stimulation of androgens, and if the androgens in the body drop significantly, the tumor will shrink. Through surgical removal of the testicles or drug injections, the patient’s androgen levels can be suppressed to stop the tumor’s progression, in a way known as endocrine therapy. Endocrine therapy is done after radical prostate cancer surgery and can prevent the disease from coming back. However, it is not done as soon as possible after surgery, but the PSA should be tested regularly and the treatment should be started after the PSA rises to a certain level – after radical prostate cancer surgery, the PSA should be checked once a month, in most cases, the first month is below 0.2, if it does not fall below 0.2, you can still wait for another month, and the next two months if If the PSA continues to fall and drops below 0.2, then the patient can rest assured, and after that, a check every three months can be done; however, if the follow-up examination reveals that the PSA rises and is greater than 0.2, it is called biochemical recurrence, and endocrine therapy should be considered. If radical surgery is not done, prostate cancer can also be treated with radiation therapy, also called radical radiotherapy, which can also serve the purpose of inhibiting tumor development. The PSA test for radiotherapy patients is less demanding compared to surgery patients, and endocrine therapy can be done when it is greater than 1. When endocrine therapy is done, radiotherapy should not be stopped either, and the combined treatment of the two modalities can have a better inhibiting effect. If prostate cancer is more malignant or has bone metastasis, surgery and radiotherapy cannot solve the problem, endocrine therapy should be used to stop tumor development. Of course, endocrine therapy does not have to wait until prostate cancer surgery or radiotherapy fails to be used, but can also be started in the early and middle stages of the disease. For example, if one has cardiovascular disease or other serious diseases of a more dangerous degree than prostate cancer, resulting in a short life expectancy, or if the patient has difficulty or cannot undergo surgery for some reason, endocrine therapy is also indicated for a better quality of life. It has been suggested that endocrine therapy, or neoadjuvant therapy, can be done three months before prostate cancer surgery to make the tumor smaller and the margins clearer, allowing for a smoother surgery. However, from a practical point of view, endocrine therapy can aggravate tissue adhesions, which in turn increases the difficulty of surgery. According to foreign literature, neoadjuvant therapy does not reduce the difficulty of surgery and is not effective in delaying the time of tumor recurrence. Therefore, I do not recommend endocrine therapy before prostate cancer surgery. In addition, not all prostate cancers can be treated with endocrine therapy. For example, prostate sarcoma with higher malignancy does not have a high PSA after the disease, because this sarcoma does not depend on androgens for growth, so controlling androgens cannot inhibit its development, and it cannot be treated with endocrine therapy. Note: PSA units in this article are all ng/ml