Prostate Specific Antigen (Free) PSA Test

Prostate-specific antigen (PSA) is a glycoprotein produced only by certain cells within the male prostate gland. Normally, very little PSA is secreted in the blood. Elevated levels of PSA have been associated with benign and malignant prostatic disorders and are considered as one of the markers for early detection of prostate cancer in men over 50 years. PSA exists in multiple forms, one where it is bound by a protein complex and another in free form. The presence of Total PSA alone is not sufficient for a proper analysis; therefore both the total and free forms are calculated. A ratio of total to free form PSA is used for the diagnosis.

PSA levels are affected by other medical conditions other than prostate cancer, therefore it is important that the patient inform the practitioner about the following prior to the testing: Your medical history, including any benign prostate conditions such as prostatitis Any other tests that have been conducted for the prostate condition List of medications that are being taken Dietary restrictions that are being followed Based on this history, the practitioner may advice you about any diet restrictions, and usage of medications that need to be followed. It is recommended that you wear comfortable clothing that will allow easy access to your forearm on the day of testing.

The free PSA test is considered as one of the markers for early detection of prostate cancer. This test along with digital rectal exam (DRE) will help in avoiding biopsies in men with benign prostate conditions and having a low risk of cancer. Biopsies are often painful and expensive procedures, sometimes leaving permanent side effects. The test also indicates if further biopsy and other prostate tests are required. It also helps in monitoring and management in patients with prostate cancer.

A blood sample is drawn from the vein from the forearm after the skin surface is cleaned with antiseptic. The blood sample is then subjected to immunoassay testing to assess the levels of total PSA and free PSA in the serum. The diagnosis is then made based on the patient’s history including age, existing disorders and medical conditions and other parameters. The test report provides normal range and diagnosed values of Total PSA, and the percentage of free PSA in the Total PSA according to age. A range of 4.0-10.0 ng/mL, a free: total PSA ratio < or =0.10 indicates a risk of cancer.