Enzyme immunoassay of prostatic acid phosphatase after prostatic examination. Correlation with prostate size and...

Variation in serum prostatic acid phosphatase (PAP) after prostatic digital examination was studied in 22 patients, 18 with benign prostatic hyperplasia (BPH), and 4 with prostatic carcinoma. Serum PAP was determined by enzyme immunoassay (EIA) and compared with standard enzymatic assay (EA). Prostatic tissue from transurethral resection (TUR) was subjected to routine pathologic examination and stained for PAP. PAP level increased above reference range and up to several-fold in 12 of 22 patients (54.5%) by EIA and in 22.7 percent by EA. The increase in PAP correlated positively with the prostate size estimated by digital palpation (R = 0.82, P less than 0.001). There was no definite correlation between the histologic parameters studied and the increase in PAP. No day-to-day variation in PAP level was detected in 8 other patients when samples were taken at 7 AM for three successive days. For proper comparison of PAP value, we suggest that sampling time should be fixed and specimens should be taken before prostatic manipulation.