Acid phosphatase and prostatic carcinoma

Assays for acid phosphatase activity in serum derived from either peripheral blood or bone-marrow blood are subject to a number of interferences. The analytical problems can be minimized by using as specific a substrate as possible, the best current one probably being thymolphthalein monophosphate. Application of immunological methods appears very promising but will require more extensive study. Assay of bone-marrow serum acid phosphatase is more sensitive than is assay of serum acid phosphatase for detecting metastases to the bone. However, even with specific substrates, falsely positive results can be expected on occasion. Acid phosphatase determinations in the blood bathing the bone marrow, in concert with histological examination of a bone biopsy, appear to be valuable adjuncts in evaluating patients with suspected or established carcinoma of the prostate.