New tests are far more dependable.
Prostate Specific Antigen is made by prostate cells and released into the bloodstream. The larger your prostate, the more PSA you make, so PSA determines size of the prostate gland, rather than prostate cancer. Since prostate cancer and benign enlargement of the prostate both are associated with an enlarged prostate glands, both are also associated with an elevated blood PSA level. On the other hand, a sudden rise in PSA can mean that the gland is enlarging rapidly which can be a sign of cancer or an acute infection. Another test depends on the ratio of free PSA to bound PSA in the blood.