The diagnostic value of urinary Crosslaps and serum alkaline phosphatase in patients with prostate cancer.

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.

Urinary excretion of deoxypyridinoline in patients with breast cancer.

Deoxypyridinoline (Dpyr), a crosslink of collagen molecules found in bone and excreted in urine during bone degradation, was measured in patients with breast cancer. Four groups of patients included, 42 premenopausal (32 without and 10 with bone metastases) and 65 postmenopausal (39 without and 26 with bone metastases) women. For comparison, 21 healthy women were studied. Dpyr was measured in urine samples using an enzyme immunoassay. Breast cancer patients showed elevated levels of Dpyr, irrespective of whether or not they had bone metastases. Dpyr excretion was more increased in postmenopausal patients with bone metastases. The results reflect an important bone turnover in breast cancer. The data suggest that Dpyr assay seems promising to evaluate the rate of bone loss and the response to treatment in bone metastases.

[The perfused liver. A model for studying hepatic metabolism of drugs: the example of 5-fluorouracil]. / Le foie perfusé. Moyen d'etude du métabolisme hépatique des médicaments: exemple du 5-fluorouracile.

Isolated perfused rat liver has been used as a model to study hepatic metabolism of 5-fluorouracil (FUra) at different doses. Results show that FUra concentrations dropped rapidly. At higher doses, however, hepatic enzymes were saturated and FUra no longer disappeared. Nevertheless, substantial doses can be administered without significant hepatic parenchyma destruction.