[Evaluation of a monoclonal antibody-based enzyme immunoassay (IQ(Bio) PAP-AELIA kit) for prostatic acid phosphatase].

The clinical application of enzyme immunoassay (EIA) for prostatic acid phosphatase (PAP) is reported. PAP concentration was measured by an IQ(Bio)PAP-AELIA kit. Serum samples were collected from 20 healthy individuals, 31 patients with benign prostatic hypertrophy, 14 patients with prostatis, 23 patients (47 samples) with prostatic cancer and 29 patients with various other malignancies. The coefficients of variation (%CV) in intraassay and interassay ranged from 2.3 to 4.4%, and from 3.0 to 3.6%, respectively. The recovery rate in the dilution test and recovery test were 106.2 +/- 8.9% and 101.3 +/- 6.9% respectively. A significant correlation (r = 0.994, p less than 0.01) was observed between EIA and RIA methods in the prostatic cancer patients. PAP concentration was elevated above 2.0 ng/ml in 0/2 (0%) of the treated patients with stage B prostatic cancer, 1/5 (20%) of those with stage C, 6/16 (38%) of those with stage D, and in 4/5 (80%) of the untreated patients with stage D prostatic cancer. False positive results were seen in 2/31 (6%) of the patients with benign prostatic hypertrophy, 3/14 (21%) with prostatis and 3/29 (10%) of the patients with various other malignancies. In the majority of the false positive cases, elevated levels were only just above the normal value. In conclusion, the PAP level measured by this EIA kit was correlated with the clinical response to hormone therapy for prostatic cancer.