Common blood tests for prostateThe prostate is a walnut-sized gland located between the bla... Full Definition cancerCancer is a group of diseases where cells grow abnormally an... Full Definition measure Prostate-Specific Antigen (PSA), an enzymeEnzymes are molecules that accelerate chemical processes in ... Full Definition produced in the prostate that ends up in sperm and also in the bloodstream. Different measures of PSA help doctors determine if cancer is present and if it is growing. Multiple tests may be performed from a single blood draw.