Low bone mineral density and high incidences of fractures and vitamin D deficiency in 52 pediatric cancer survivors

Objective: To evaluate bone mineral density (BMD), fractures, and vitamin D deficiency in pediatric patients in complete remission of solid tumor; and to identify risk factors for these three abnormalities. Study Design: Data were collected prospectively after completion of cancer treatment. Hormonal and vitamin D deficiencies were treated. The patients were evaluated again 1 year later. Patients: 52 consecutive patients, 30 boys and 22 girls. Among them, 21 completed the second evaluation. Measurements: A clinical examination, nutritional assessment, and laboratory workup were performed. BMD was measured by absorptiometry. Results: Calcium intake was inadequate in 75% of patients and vitamin D reserves were low in 61.5%. BMD was low at the spine in 32.7%, and at the femur in 24% of patients. Spinal and femoral BMD Z-scores correlated significantly with each other. Femoral BMD Z-score showed significant positive correlations with changes in body mass index, urinary calcium/creatinine ratio, and time since treatment completion, and a significant negative correlation with treatment duration. Fractures were noted in 10 patients but were not correlated with BMD. In the 21 re-evaluated patients, no significant improvements were found in calcium intake, vitamin D status, or BMD Z-score. Conclusions: Survivors of childhood solid cancer have high rates of insufficient calcium intake, vitamin D deficiency, low bone mass and fractures.