Prostatic Acid Phosphatase (PAP)

An adjunct in the evaluation of possible prostatic malignancy and useful in monitoring therapeutic progress.

Prostatic acid phosphatase has been used as a tumor marker ever since the observation by Gutman in 1938¹ that elevated levels of this enzyme are found in patients with metastatic prostate cancer. PAP determination in conjunction with PSA measurements is useful in assessing the prognosis of prostate cancer.² Measurement of two markers allows identification of prostate cancer patients who have an elevation of PAP but not of PSA, and thus help monitoring the course of disease and response to treatment. PAP is more specific than PSA and less false-positives are seen due to benign prostatic hyperplasia.

1. Gutman AB, Gutman EB. An “acid” phosphatase occurring in the serum of patients with metastasizing carcinoma of the prostate gland. J Clin Invest. 1938 Jul; 17(4):473-478. PubMed 16694594

2. Powell P, Neal D, Gibb I, Wilson L, Hall R. Immunologically measured serum markers and their role in the management of prostate cancer. Eur Urol. 1988; 15(1-2):48-53. PubMed 2463921

Killian CS, Emrich LJ, Vargas FP, et al. Relative reliability of five serially measured markers for prognosis of progression in prostate cancer. J Natl Cancer Inst. 1986 Feb, 76(2):179-185. PubMed 2418245