Alterations in bone turnover and impaired development of bone mineral density in newly diagnosed children with cancer: A 1-year prospective study

In the present study, longitudinal changes in bone mineral density, bone tu rnover, and bone hormonal metabolism were evaluated in newly diagnosed chil dren with cancer. Lumbar spine (L2-L4) and femoral neck bone mineral densit ies(grams per cm(2)) were measured by dual energy x-ray absorptiometry in 2 8 children (age, 2.9-16.0 yr; median, 8.0 yr; 10 acute lymphoblastic leukem ias, 18 solid tumors) at diagnosis and after a l-yr follow-up. Apparent vol umetsic density (grams per cm(3)) was calculated to minimize the effect of bone size on BMD. Serum levels of osteocalcin (OC), type I collagen carboxy l-terminal propeptide (PICP), and type I collagen carboxyl-terminal telopep tide were measured serially during the study. Serum 25-hydroxyvitamin D, 1, 25-dihydroxyvitamin D, insulin-like growth factor I(IGF-I), and IGF-binding protein-3 were analyzed at diagnosis and at l-yr follow-up. A significant decrease in femoral bone mineral density and apparent volumet ric density was observed during the year after diagnosis [(mean(SD), -10.1% (8.8%) and -11.3%(8.1%) respectively; P<0.01], whereas age- and sex-matched controls showed annual increments of +5.4% (7.7%; P<0.01) and +0.7% (5.7%; P = NS) respectively. The markers of bone formation (PICP and OC) were sig nificantly decreased at diagnosis. By the end of the follow-up, PICP and OC were normalized, whereas the marker of bone resorption (type I collagen ca rboxyl-terminal telopeptide) was significantly increased. Reduced levels of 25-hydroxyvitamin D, 1,25-dihydroxyvitamin D, and IGF-binding protein-3 we re observed during the study. To conclude, increased bone resorption and impaired development of femoral bone density were observed in children with cancer during chemotherapy. Def icient accumulation of bone mass may lead to impaired development of peak b one mass and predispose children with cancer to increased risk of osteoporo sis and diminished skeletal resistance to fractures later in Life.