The effect of manipulation of the prostate gland on serum prostate-specific acid phosphatase measured by radioimmunoassay.

We investigated the effects of digital prostatic palpation, cystoscopy, and biopsy of the prostate on the concentrations of serum prostate-specific acid phosphatase (PAP) measured by radioimmunoassay. Serum concentrations of PAP in patients with normal or hyperplastic prostates did not exceed the upper limit of our reference range (4 microgram per liter) during the 48 hr after digital prostatic palpation. The serum concentrations of PAP did not significantly increase in patients with carcinomatous prostates after digital examination of the prostate. Serum PAP did increase in patients with benign prostatic hyperplasia soon after cystoscopy of biopsy of the prostate. No diurnal variation in the serum concentrations of PAP during the follow-up of 48 hr was detected in the patient groups with normal, benign hyperplastic, or carcinomatous prostates not subjected to rectal examination.