Measurement of bone mineral density in children with cancer.

To the Editor:

The article by Aldhafiri et al1 raises several clinically relevant issues. As addressed in the principle objective given in the study, measurement of bone mineral density in children by dual-energy x-ray absorptiometry (DXA) requires adjustment for height and weight, therefore providing validation of our observations reported in 2009.2 Secondly, it is important to establish local norms with DXA and not rely on the ranges provided by the manufacturers of densitometers.3 Thirdly, body mass index is an imperfect measure of nutritional status in children with cancer,4 in whom arm anthropometry appears to provide a better estimate.5 Finally, DXA offers accurate determinations of body composition: lean body mass (fat-free mass), fat mass, and whole-body bone mineral content, summing up to body weight.3 It would be of interest to know whether, in children examined by Aldhafiri and colleagues, there was a relationship between lean body mass and bone mineral density corrected for height and weight.