The prostate-specific antigen (PSA) blood test is a laboratory test that measures the level of PSA in a man’s blood. PSA is a protein produced by the prostate gland, and elevated levels of PSA can be an indicator of prostate cancer or other prostate-related conditions.

During the test, a small sample of blood is drawn from a vein in the arm and sent to a laboratory for analysis. The normal range for PSA levels varies by age and other factors, but generally ranges from 0 to 4 nanograms per milliliter (ng/mL).

Elevated PSA levels can indicate the presence of prostate cancer, but they can also be caused by other factors, such as inflammation of the prostate gland (prostatitis), benign enlargement of the prostate gland (benign prostatic hyperplasia), and recent ejaculation or physical activity.

The PSA blood test is commonly used as a screening tool for prostate cancer in men over the age of 50, or earlier for men with a family history of prostate cancer or other risk factors. It can also be used to monitor the progression of prostate cancer and the effectiveness of treatment.

It’s important to note that the PSA blood test is not specific to prostate cancer, and a high PSA level does not necessarily mean that a man has cancer. Further testing, such as a biopsy, may be necessary to confirm a diagnosis. A healthcare provider can interpret the results of the test in the context of the individual’s medical history and other test results, and develop an appropriate treatment plan if necessary.