False positive values of PAP and PSA in complicated and non-complicated benign prostatic hypertrophy

Cancer of the prostate has become the most frequent form of cancer in men. Different tests have been used in cancer of the prostate, including prostate acid phosphatase (PAP) and the prostate specific antigen (PSA). Their value as diagnostic screening is disputed, as it is known that there are false positives for both markers in benign prostate conditions. In order to explain their possible diagnostic value, we studied 112 patients with well-documented benign prostate hyperplasia. The data included in this study were: estimated weight, urinary infection, bladder catheter and histopathological study. By using as cut-off 4 ng/ml for PAP and 10 ng/ml for PSA we found a percentage of false positives of 13% and 14% respectively. These percentages were in relation to the weight of the gland in each cases and in the case of PSA to the patient's clinical situation (infection, catheter).