PSA
It is a substance produced almost exclusively in the prostate and plays a role in fertility. The vast majority is actually released into the ejaculate but tiny amounts are released into the blood stream and can be detected by a simple blood test. Abnormally high levels of PSA can be an indication of disease of the prostate. Common reasons for a high PSA level in the blood stream may include prostate cancer, large prostates, and age related inflammation of the prostate or infection of the prostate. Obviously the first concern is to exclude prostate cancer.
The bladder is the organ that stores urine and the urethra is the tube that drains urine out through the penis. The prostate lies immediately beneath the bladder and completely surrounds the urethra and lies immediately in front of the rectum (back passage). Your doctor would have performed on you a Digital Rectal Examination (DRE) (examination via the back passage) of the prostate, an otherwise inaccessible internal organ. Age related enlargement is not a particular concern but if the gland feels abnormally firm or hard, it may sometimes be an indication of an abnormal growth in the prostate gland.