Screening methods to detect prostate cancer

Prostate cancer usually does not result in symptoms in men till the late stages. It is known to be the most common type of cancer in men. As per the American Urological Association, men aged 55 to 69 should be recommended a baseline serum PSA test and prostate exam (DRE) in order to understand the risk of prostate cancer. A regular screening for prostate cancer has been recommended by urologists, using PSA and DRE in men. If any of the initial warning signs for prostate cancer are noticed, the following tests would be used for screening:

  • Elevated prostate serum antigen (PSA): While the PSA test is not used for the actual detection or diagnosis of prostate cancer, it definitely gives an indication of the risk in developing prostate cancer. A PSA test is usually a part of a regular health screening process. If the levels of prostate serum antigen are shown to be elevated, a prostate biopsy would further be performed to confirm the presence of prostate cancer. The test can be uncertain as there is no universally accepted level of PSA above which the levels are considered abnormal. Hence, having a high threshold could mean avoiding unnecessary biopsies, but it would also risk missing potential cancer cases. Setting the threshold too low might reduce the number of cancer cases that are missed at early stages but might also lead to detection of cancers that are not even clinically significant to be treated.
  • Abnormal digital rectal exam (DRE): If an abnormal prostate exam is encountered in the procedure, a case of prostate cancer might be suspected. In the examination, the doctor would insert a gloved and lubricated finger into the rectum to examine the back of the prostate for anything abnormal. Any kind of asymmetry, tenderness, nodules, swelling, or irregular developments on the prostate could be an indication of cancer. On the other hand, symmetric enlargement and firmness of the prostate would indicate benign prostatic hyperplasia. If any abnormalities are noticed during the DRE, the doctor would be prompted to perform a prostate biopsy to confirm the presence of prostate cancer. Almost 25 to 30% of the prostate tumors are located in parts of the gland that cannot be examined or felt during a digital rectal examination. About 30% of men with an abnormal digital rectal examination are detected with prostate cancer.
  • Elevated prostate cancer antigen 3 (PCA3): This test can be extremely helpful to differentiate between PSA elevations that occur because of cancer development and other non-specific PSA elevations. There isn’t enough information to determine the use of this test for prostate cancer screening. It can help in confirming the need for a biopsy.