EFFICACY OF SKELETAL ALKALINE-PHOSPHATASE AND PROSTATE-SPECIFIC ANTIGEN IN THE DIAGNOSIS OF BONE METASTASIS IN CANCER OF THE PROSTATE

Purpose: To study the efficacy of prostate-specific antigen (PSA) and skeletal alkaline phosphatase (SAP) as staging markers in discriminati ng patients with cancer of the prostate (CaP) with (M+) and without bo ne metastases (M0), Material and Methods: 73 patients with untreated C aP entered the study. After staging the patients were divided into 3 g roups: group I, patients with CaP and bone metastases (n = 21); group II, patients with locally advanced CaP without bone metastases (n = 26 ), and group III, patients with clinically localized CaP without bone metastases (n = 26), Results: None of the M0 patients but 71% of the M + patients exhibited an increased SAP. A corresponding cutoff point of 100 ng/ml for PSA showed that 19% of MO patients and 71% of the M+ pa tients exhibited a value of > 100 ng/ml, This resulted in a sensitivit y and specificity of 71 and 100% of SAP and 71 and 81% for PSA, respec tively. Conclusion: SAP could become a useful marker in the evaluation of patients with newly diagnosed CaP as it provides additional inform ation concerning the skeletal status of these patients.