Prostate cancer often occurs in silent mode, without symptoms. To overcome this problem, most doctors recommend PSA (prostate-specific antigen) test and digital rectal examination for the elderly, for patients in whom the disease may have exhibited symptoms or where it may be silent. PSA is indicated for detection of prostate cancer. The PSA test detects the levels of a specific protein produced by the prostate gland. It is most often recommended for prostate cancer screening in elderly males.
 

The PSA test is expressed as levels of prostate-specific antigens in nanograms per milliliter of blood (ng/ml). Normally, in prostate cancers, the levels of PSA test are found to be elevated. There are few examples where the PSA test shows elevated levels but the individual does not have cancer or symptoms of prostate enlargement. These are called false positive PSA tests. A few conditions such as the inflammation of prostate (prostatitis) and BPH (benign prostatic hyperplasia) are also associated with raised PSA levels. These conditions even cause symptoms that appear similar to those found in prostate cancer. The raised levels of PSA test and confirmation by digital rectal examination of the elderly individual help doctors diagnose prostate cancer. The FDA has approved the PSA test for screening prostate cancer in elderly men.
 

As prostate cancer usually does not present any early symptoms or indicators, screening using the PSA test and a digital rectal examination is necessary. In case symptoms like urinary urgency, inability to maintain flow of urine, or pain are present, some suspicion of prostate cancer may arise. These symptoms appear because the enlarged prostate gland exerts pressure over the urethra. People who have family history of prostate cancer should always look for early prostate cancer symptoms and go for early screening of PSA levels.
 

By itself, the PSA test cannot confirm the presence of prostate cancer. Other symptoms associated with it and a digital rectal examination is necessary for confirming the diagnosis. Doctors often advise prostate biopsy if the PSA test indicates that levels of PSA are elevated. For instance, the levels may be elevated for a person with a urinary tract infection.

Sometimes false negative results are also observed where prostate cancer is confirmed by biopsy even though the PSA test levels are normal. Doctors consider these variations before diagnosing prostate cancer. Though the PSA test has some limitations, its relevance in identifying or screening for prostate cancer cannot be ignored, especially as many people who show no symptoms are only diagnosed at later stages when the cancer has spread to nearby organs and parts.