Decreased bone mineral density and alteration in biochemical bone metabolism markers in children affected by bone tumors after completion of therapy.

Abstract

The aim of this study was to assess bone mineral density (BMD) and biochemical bone metabolism markers in patients with bone tumors after anti-cancer treatment. The study included 27 patients (median age 15 years) with malignant bone tumors and 27 healthy children. In all subjects, BMD and body composition were measured by dual-energy x-ray absorptiometry. Serum bone markers were determined by immunoenzymatic assays. After completion of treatment, patients with bone tumors had significantly decreased total and lumbar spine BMD. We observed lower calcium and vitamin Dlevels in patients and comparable values of bone turnover markers (carboxyterminal telopeptide of collagen type I- CTX, bone alkaline phosphatase - BALP and osteocalcin - OC) in both groups of children. However, the level of carboxylated osteocalcin (cOC) was significantly lower (p<0.01) and undercarboxylated OC (ucOC) was higher (p<0.05) in patients than in controls. Additionally, we observed similar values of anthropometric parameters in the subgroups of patients treated with methotrexate (MTX) or without MTX. In patients treated without MTX we found lower (p<0.05) ratio of cOC/ucOC, lower vitamin Dlevel and higher CTX concentrations. Patients with bone tumors after anticancer treatment had decreased bone mineral density and alterations in bone metabolism markers with potential decrease in bone formation. bone cancer survivors, bone mineral density, bone formation markers, bone resorption markers, methotrexate.