The significance of bone marrow acid phosphatase in patients with prostatic carcinoma

Prostatic acid phosphatase in serum and bone marrow in patients with prostatic carcinoma

Sixty-two per cent of 61 patients with prostatic carcinoma showed elevated levels of serum acid phosphatase, analysed by radioimmunoassay (RIA). Enzymatically determined serum acid phosphatase was raised in only 38% of the same patients. Bone marrow acid phosphatase determined by RIA was raised in 41%. In untreated metastatic patients with prostatic carcinoma, radioimmunologically determined serum acid phosphatase was elevated in 12 of 13 patients, whereas bone marrow acid phosphatase (RIA) and enzymatically determined serum prostatic acid phosphatase were increased only in about half of the patients. In a control group the upper reference limit of bone marrow acid phosphatase determined by RIA was significantly raised above that obtained by serum analyses. This indicates that nonprostatic acid phosphatases (possibly from bone marrow cells) cross-react with prostatic acid phosphatase in an unpredictable way, even when using a specific radioimmunoassay. In patients with metastatic carcinoma of the prostate, the results of bone marrow acid phosphatase determinations, analysed by RIA, seem to lack diagnostic and/or prognostic information additional to that obtainable by serum acid phosphatase (RIA) analysis.

Radioimmunoassayable prostate-specific acid phosphatase in peripheral and bone marrow sera compared in diagnosis of prostatic cancer patients

Measurements of human prostate-specific acid phosphatase by radioimmunoassay in peripheral and bone marrow sera were compared. We studied 20 patients with benign prostatic hyperplasia, 27 with untreated prostatic cancer without bone metastases and 11 with metastases, in addition to 7 with cancer treated by hormonal therapy. The prostate-specific acid phosphatase concentrations in peripheral and bone marrow serum samples were equal and did not exceed the upper limit of our health-associated reference interval, 2.8 microgram. per 1. (mean plus 2 standard deviations) in patients with prostatic hyperplasia. Of 27 prostatic cancer patients without bone metastases the concentration of prostate-specific acid phosphatase was elevated in the peripheral sera of 20 and in the bone marrow sera of 21, and 21 had an extracapsular tumor (stage T3 to T4). Prostate-specific acid phosphatase concentrations were elevated in peripheral and bone marrow serum specimens of all 11 patients with metastases and bone marrow cytology studies were positive in 2. There was no difference in prostate-specific acid phosphatase concentrations in peripheral and bone marrow serum specimens from prostatic cancer patients undergoing hormonal treatment. We conclude that the use of bone marrow serum for the measurement of radioimmunoassayable prostate-specific acid phosphatase in prostatic cancer patients does not provide any further information in regard to the detection of prostatic cancer compared to the use of peripheral serum specimens. Falsely positive findings in bone marrow specimens were not observed with the method used.