The most commonly used clinical staging method for prostate cancer is TNM staging, but this staging is cumbersome. A simple method can be understood as early stage of prostate cancer if the tumor is confined to the prostate gland without invasion of surrounding organs and distant metastasis. If the prostate cancer invades the surrounding organs, such as the bladder neck, seminal vesicle gland, rectum, etc., it can be considered to reach the middle stage of prostate cancer. If distant metastasis, i.e. lymph nodes, or the most common site of metastasis, bone, is present, it can be considered as advanced stage of prostate cancer. If the symptoms continue to worsen, metastasis to internal organs may also occur.