An antigen whose concentration increases significantly five to ten years prior to the diagnosis of prostate cancer. This means that PSA level measurements could lead to a diagnosis of prostate cancer before symptoms appear. However, a series of tests is required in order to accurately gauge the probability of cancer because PSA levels can also be elevated when a man develops a noncancerous enlarged prostate.
An enzyme that is measured in a blood test to detect cancer of the prostate.
Protein produced only in the prostate gland; the level dramatically increases in patients with prostate cancer; used in diagnosis and in monitoring the response of the patient to treatment.
A substance in blood elevated in patients who have prostate cancer.
An enzyme produced by glandular tissue in the prostate gland. When the gland enlarges, greater amounts of PSA are secreted, raising the concentration of the enzyme in the blood. This is especially so in cancer of the prostate, and testing the level of PSA is an indicator that the disease may be present. There is much controversy about the use of PSA as a screening test. Its proponents claim that its use reduces deaths from prostate cancer; its opponents suggest that it does this only by bringing to light many cases that would never have needed treatment as the cancers would have remained small and confined to the prostate. Further, if the level of PSA is very high when the person is screened, the disease is already advanced; where the result is equivocal it is uncertain whether the benefits of treatment outweigh the risks.
A marker for cancer of the prostate. It is found in the blood; it is secreted by both benign and malignant prostate tumors, but cancerous prostate cells secrete it at much higher levels. Prostate-specific antigen is used as a screening test for cancer of the prostate and as a means of following the results of treatment in patients with known prostate cancer.
Blood test that detects a protein associated with prostate cancer.
A substance frequently generated by prostate cancers, which can be identified through a blood test.
This enzyme is naturally generated by the prostate gland. Elevated levels of this enzyme could signal the presence of prostate cancer, making PSA blood tests a common screening method for this cancer. However, elevated PSA levels can also be due to other conditions like benign prostatic hypertrophy or prostatitis, which is an inflammation of the prostate.