Two initial tests are commonly used to look for prostate cancer in the absence of any symptoms. One is the digital rectal exam, in which a doctor feels the prostate through the rectum to find hard or lumpy areas known as nodules. The other is a blood test used to detect a substance made by the prostate called "prostate-specific antigen" (PSA). When used together, these tests can detect abnormalities that might suggest prostate cancer.
Neither of these initial tests for prostate cancer is perfect. Many men with a mildly elevated PSA do not have prostate cancer, and men with prostate cancer may have normal levels of PSA. Also, the digital rectal exam does not detect all prostate cancers, as it can only assess the back portion of the prostate gland.
The diagnosis can only be confirmed by examining prostate cells under a microscope. This is done by performing a biopsy in a urologist's office. A small sample of tissue is taken from the prostate for testing and evaluation under a microscope.
Your doctor is likely to discuss your medical history with you. Answering questions about any history of genital or urinary disease in your family can help your doctor make an accurate diagnosis. Your doctor may also ask about any changes in your pattern of urinating.