ASSESSMENT OF THE LATE EFFECTS ON BONES AND ON BODY COMPOSITION OF CHILDREN AND ADOLESCENTS TREATED FOR ACUTE LYMPHOCYTIC LEUKEMIA ACCORDING TO BRAZILIAN PROTOCOLS.

Poliana Cristina Carmona Molinari,Maria Lucia De Martino Lee,Henrique Manoel Lederman,Eliana Maria Monteiro Caran

doi:10.1590/1984-0462/;2017;35;1;00005

Abstract

ABSTRACTObjective: To evaluate the impact of therapy on bone mineral density (BMD) and body composition in survivors of acute lymphoblastic leukemia (ALL) treated in accordance with Brazilian protocols by the Brazilian Cooperative Group of Treatment of Lymphoblastic Leukemia in Childhood (GBTLI) LLA-93 and LLA-99. Methods: A cross-sectional study with 101 patients was performed. BMD and body composition were evaluated using bone densitometry and were interpreted according to the age group and the reference population. Values between -1.1 and -1.9 in the group of children under 20 years were considered as risk group for low BMD z-scores. BMD values were compared to clinical characteristics, treatment received and body composition. A chi-square test, Fisher’s exact test, likelihood ratio and Student’s t-test were applied, with a 5% significance level. Results: The patients presented a frequency of fractures of 2%, of osteonecrosis, 2%, and of low BMD, 2.9%. In the group of 79 patients under 20 years of age, three had low BMD. The 16 that presented risk for low BMD, demonstrated lower valutes in lumbar vertebrae L1-L4 (p=0.01) and whole body (p=0.005), and smaller values of lean body mass (p=0.03). In the group of 22 patients over 20 years of age, ten had osteopenia. Conclusions: The low impact of treatment on BMD of this study confirms the concept that the bone mass gain occurs with increasing age and that the treatment does not influence the process. The population at risk for low BMD values presented lower bone mass values and could benefit from a long-term monitoring for possible bone toxicity.

Highlights

The therapeutic progress obtained in the treatment of children with acute lymphocytic leukemia (ALL) over the past 50 years has resulted in cure rates of around 80%, culminating in an impactful increase in the number of survivors
This population represents a group with increased risk for comorbidity related to treatment and the disease itself.1.2 Changes in bone metabolism and body composition are considered important adverse late effects and represent a significant cause of morbidity in this population, through pain, fractures, decrease of bone mineral density (BMD) and chronic impairment of bone function.3.4 Exposure to corticosteroids, methotrexate, mercaptopurine and radiation, associated with low calcium intake, decreased physical activity, and obesity are some of the factors that lead to low BMD.[5,6,7]
With regard to characteristics at the time of diagnosis, the mean age was 5.2 ± 3.6 years, and 94% of patients had an immunophenotypical classification of precursor B-cell ALL. 78.2% of the patients presented an initial leukocyte count lower than 50,000 cells/mm[3], and central nervous system (CNS) infiltration was diagnosed in nine patients

Summary

Introduction

The therapeutic progress obtained in the treatment of children with acute lymphocytic leukemia (ALL) over the past 50 years has resulted in cure rates of around 80%, culminating in an impactful increase in the number of survivors This population represents a group with increased risk for comorbidity related to treatment and the disease itself.1.2 Changes in bone metabolism and body composition are considered important adverse late effects and represent a significant cause of morbidity in this population, through pain, fractures, decrease of bone mineral density (BMD) and chronic impairment of bone function.3.4 Exposure to corticosteroids, methotrexate, mercaptopurine and radiation, associated with low calcium intake, decreased physical activity, and obesity are some of the factors that lead to low BMD.[5,6,7] patients treated for ALL can recover lost bone mass during the post-treatment period, a percentage of them will not reach their maximum BMD acquisition potential, presenting significant bone deficit.[1]. It must be performed and interpreted in accordance with the pediatric references for each population, whose norms have been previously published.[8,9,10]

Methods

Results

Conclusion