Objective: To determine whether the urinary excretion of Crosslaps and serum alkaline phosphatase (ALP) are useful bone markers in patients with prostate cancer.
Patients and methods: The study included 112 patients, comprising 25 with benign prostatic hyperplasia and 87 with carcinoma of the prostate, 41 of whom had localized prostate cancer and 46 with bone metastases. In the last group, 16 were stable and 30 were in clinical progression. Prostate-specific antigen (PSA) and the bone markers serum bone ALP and urinary Crosslaps were determined on the same day.
Results: The rates of excretion of Crosslaps were significantly greater in patients with than in those without bone metastases. Only Crosslaps showed a significant difference between patients with stabilized metastatic disease and those with no bone involvement. Crosslaps had a higher specificity and positive predictive value than had PSA level in patients with bone metastases, and a higher sensitivity than bone ALP.
Conclusion: These preliminary findings suggest that Crosslaps may be useful as an additional bone marker in patients with prostate cancer and may provide information of the metastatic spread to bone in these patients. Prospective studies with serial measurements of bone markers are currently underway to relate these results to the progression of disease and to evaluate the response to treatment of bone metastases.