ABSTRACT
The aim of our study was to evaluate bone metabolism with measurement of bone mineral density (BMD) after management (chemo-, radiotherapy) for childhood acute lymphoblastic leukemia (ALL). Bone mineral density (g/cm2) of lumbar spine was measured by dual energy X-ray absorptiometry (Norland bone densitometer) in 18 children with ALL and a median of 34 months' post-diagnosis with no history of relapse, secondary malignancy, or transplantation. In addition, patients' BMDs were correlated with particular attention to age, sex and time (years) from completion of chemotherapy. The results were compared with healthy age- and sex-matched controls of the same population and expressed as standard deviation scores (SDS). Mean age of children was 9.8 +/- 3.7 years. Of 18 children (10 boys and 8 girls), 13 were grouped as standard and 5 as high-risk, respectively. Based on z-score values, 9 were classified as normal (z-score <1 SD), 7 as osteopenic (z-score 1-2.5 SD) and 2 as osteoporotic (z-score >2.5 SD). Children with ALL had reduced lumbar BMDs (z score -0.99) in comparison to healthy controls (z score -0.14) (p=0.011), which is indicative of relative osteopenia. Moreover, the reduced BMD was associated with patient age (z score -0.14 and -1.52 for ages <10 and >10 years, respectively, p=0.016). Reduced BMD was not correlated with time from completion of chemotherapy (p=0.33), risk group (p=0.9) and sex (p=0.3). We conclude that children's BMDs are reduced after completion of chemotherapy for ALL. The causes are multifactorial and mainly related to antineoplastic treatments, such as corticosteroids and methotrexate, physical inactivity and cranial irradiation. We suggest that further studies are needed to evaluate the long-term effect on BMD in these children and to prevent pathological fractures later in life.
Subject(s)
Antineoplastic Agents/adverse effects , Bone Diseases, Metabolic/etiology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/complications , Absorptiometry, Photon , Bone Density , Bone Diseases, Metabolic/diagnostic imaging , Case-Control Studies , Child , Female , Humans , Lumbar Vertebrae/diagnostic imaging , Male , Osteoporosis/diagnostic imaging , Osteoporosis/etiology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/drug therapy , SurvivorsABSTRACT
Osteopenia and osteoporosis are currently receiving particular attention as late effects of therapy in survivors of childhood acute lymphoblastic leukemia (ALL). The aim of this study was to evaluate abnormalities in bone mass and mineral homeostasis in children with ALL after induction therapy (during consolidation treatment). Lumbar spine (L2-L4) bone mineral density (BMD, g/cm(2)) was measured by dual energy X-ray absorptiometry in 20 children with ALL, a median of 25.9 months postdiagnosis and results were expressed as z-scores relative to healthy Caucasian children (controls). Serum levels of intact parathyroid hormone (iPTH), alkaline phosphatase (ALP), calcium, phosphate, and magnesium were also analyzed. In addition, the body mass indexes (kg/cm(2)) of patients and controls were calculated. Results were compared with those of 40 healthy controls. Among the 20 children with ALL (12 boys and 8 girls), 12 presented z-scores < 1 SD (normal) and 8 were osteopenic (z-score between 1 and 2.5 SD). In addition, children with ALL had reduced lumbar BMDs (z-score -0.817) in comparison to healthy controls (z-score -0.353) (p = .04). Moreover, alkaline phosphatase and intact parathyroid hormone values were significantly increased compared to controls values. The data demonstrate that bone metabolism in children with ALL during consolidation therapy is disturbed, resulting in a reduced BMD and z-score with respect to healthy controls. Since a reduced BMD predisposes to osteopenia and osteoporosis, specific attention and therapeutic interventions should be considered.
