Carcinoma of the prostate. II. Serum activity of acid phosphatase, prostatic acid phosphatase, LDH and its isoenzymes.

In 25 patients with carcinoma of the prostate (CaP) T3 and in a comparative group of 18 patients with BPH the serum enzymes of AP, tartrate labile AP, LDH, and iso-LDH were investigated simultaneously in basal conditions and after standardized transrectal prostatic biopsy. AP, PAP as well as LDH were shown to be of small diagnostic aid. The reaction of serum enzyme levels following the standardized prostatic biopsy was the same in both CaP and BPH patients. In studying LDH-isoenzymes, we found that the third fraction was elevated in almost all patients. This change is apparently not of prostatic origin, and we could not attribute it to the concomitant diseases found in some patients.