Acid Phosphatase (Prostatic Acid Phosphatase [PAP])

Acid Phosphatase (Prostatic Acid Phosphatase [PAP])
Test Description
Acid phosphatase, also known as prostatic acid phosphatase (PAP), is an enzyme found primarily in the prostate gland, with high concentrations found in the seminal fluid. It is found in smaller concentrations in the kidneys, liver, spleen, bone marrow, erythrocytes, and platelets. Acid phosphatase is used to diagnose advanced metastatic cancer of the prostate and to monitor the patient’s response to therapy for prostate cancer.
In the past, this test has been considered a tumor marker for prostatic cancer. However, with the advent of the prostate-specific antigen (PSA) test, monitoring of the acid phosphatase is decreasing in popularity. An additional use of acid phosphatase testing is testing for its presence in vaginal secretions during the investigation of cases of alleged rape.