|  | Cancer | Prostate Cancer

PSA Testing After Cancer Treatment

PSA testing, or prostate-specific antigen testing, is a procedure designed to detect a protein in the bloodstream linked to the possible presence of prostate cancer. It is most typically used as a diagnostic screening tool in presumably healthy individuals. However, PSA testing is also performed on individuals who have undergone cancer treatment. In this context, it is used to detect a possible recurrence of the original cancer.

  1. Basic Testing Guidelines

    • If you have undergone treatment for prostate cancer, your oncologist (cancer specialist) will monitor your PSA levels as part of regular follow-up examinations. According to the American Cancer Society, if your treatment involved surgery (prostatectomy), the amount of PSA in your blood will typically become undetectable within two or three months. If you were treated with radiation therapy, your PSA levels will lower gradually over an extended period that may last two years or longer. In some individuals, PSA levels rise noticeably after radiation treatment before overall reduction begins.

    Interpreting PSA Results

    • Your oncologist will usually order a PSA test every few months after your treatment. There is always a chance that your PSA levels will appear elevated during one of these procedures. While such an occurrence might prompt your oncologist to perform closer monitoring, an isolated elevation in PSA is not necessarily cause for concern. This is true for several reasons. First, modern testing methods allow doctors to track PSA even when it is present in amounts that are small enough to be potentially medically insignificant. Second, some minor fluctuation in PSA levels is to be expected when such extensive detection techniques are used. Additionally, PSA testing sometimes produces "false positive" results that indicate elevated levels of the protein when such an elevation is not actually present.

      However, if your PSA levels show a general rising trend over time, your oncologist may decide that further cancer treatment is needed. In the aftermath of surgery, he may also make this determination if your PSA levels never become undetectable. According to the National Cancer Institute, additional factors in your oncologist's decision-making process will include abnormal findings in a prostate biopsy, digital rectal exam or computed tomography (CT) scan.

    Follow-up Treatments

    • If your PSA levels are rising slowly --- defined as a doubling of PSA over a period greater than a year --- your oncologist may choose to treat you with a course of radiation therapy. Alternatively, if you are elderly or experiencing other significant illness, he may simply choose to watch your symptoms more closely. If your PSA levels are rising quickly --- defined as a doubling of PSA in three months or less --- hormone therapy, which involves chemical disruption of your body's ability to produce testosterone and dihydrotestosterone, is a main treatment option. You may also receive a clinical trial of chemotherapy. If your PSA levels are increasing at a moderate rate, you will likely be treated with radiation therapy, which in some cases may be combined with hormone therapy. Consult your oncologist for more details on potential treatment approaches.

Prostate Cancer - Related Articles