Body composition and bone mass in survivors of childhood cancer

Determinants of bone parameters in young paediatric cancer survivors: the iBoneFIT project

BACKGROUND

Bone health is remarkably affected by endocrine side effects due to paediatric cancer treatments and the disease itself. We aimed to provide novel insights into the contribution of independent predictors of bone health in young paediatric cancer survivors.

METHODS

This cross-sectional multicentre study was carried out within the iBoneFIT framework in which 116 young paediatric cancer survivors (12.1 ± 3.3 years old; 43% female) were recruited. The independent predictors were sex, years from peak height velocity (PHV), time from treatment completion, radiotherapy exposure, region-specific lean and fat mass, musculoskeletal fitness, moderate-vigorous physical activity and past bone-specific physical activity.

RESULTS

Region-specific lean mass was the strongest significant predictor of most areal bone mineral density (aBMD), all hip geometry parameters and Trabecular Bone Score (β = 0.400-0.775, p ≤ 0.05). Years from PHV was positively associated with total body less head, legs and arms aBMD, and time from treatment completion was also positively associated with total hip and femoral neck aBMD parameters and narrow neck cross-sectional area (β = 0.327-0.398, p ≤ 0.05; β = 0.135-0.221, p ≤ 0.05), respectively.

CONCLUSION

Region-specific lean mass was consistently the most important positive determinant of all bone parameters, except for total hip aBMD, all Hip Structural Analysis parameters and Trabecular Bone Score.

IMPACT

The findings of this study indicate that region-specific lean mass is consistently the most important positive determinant of bone health in young paediatric cancer survivors. Randomised clinical trials focused on improving bone parameters of this population should target at region-specific lean mass due to the site-specific adaptations of the skeleton to external loading following paediatric cancer treatment. After paediatric cancer diagnosis, years from peak height velocity (somatic maturity) is critical for bone development.

Bone mineral density surveillance for childhood, adolescent, and young adult cancer survivors: evidence-based recommendations from the International Late Effects of Childhood Cancer Guideline Harmonization Group

Childhood, adolescent, and young adult cancer survivors are at increased risk of reduced bone mineral density. Clinical practice surveillance guidelines are important for timely diagnosis and treatment of these survivors, which could improve bone mineral density parameters and prevent fragility fractures. Discordances across current late effects guidelines necessitated international harmonisation of recommendations for bone mineral density surveillance. The International Late Effects of Childhood Cancer Guideline Harmonization Group therefore established a panel of 36 experts from ten countries, representing a range of relevant medical specialties. The evidence of risk factors for very low and low bone mineral density and fractures, surveillance modality, timing of bone mineral density surveillance, and treatment of very low and low bone mineral density were evaluated and critically appraised, and harmonised recommendations for childhood, adolescent, and young adult cancer survivors were formulated. We graded the recommendations based on the quality of evidence and balance between potential benefits and harms. Bone mineral density surveillance is recommended for survivors treated with cranial or craniospinal radiotherapy and is reasonable for survivors treated with total body irradiation. Due to insufficient evidence, no recommendation can be formulated for or against bone mineral density surveillance for survivors treated with corticosteroids. This surveillance decision should be made by the survivor and health-care provider together, after careful consideration of the potential harms and benefits and additional risk factors. We recommend to carry out bone mineral density surveillance using dual-energy x-ray absorptiometry at entry into long-term follow-up, and if normal (Z-score > -1), repeat when the survivor is aged 25 years. Between these measurements and thereafter, surveillance should be done as clinically indicated. These recommendations facilitate evidence-based care for childhood, adolescent, and young adult cancer survivors internationally.

Relationships of Bone Mineral Density to Whole Body Mass, Fat Mass and Fat-free Mass in Long-term Survivors of Acute Lymphoblastic Leukemia in Childhood

Body size influences bone mineral density (BMD) in health. Relationships of BMD with body mass index, fat mass (FM), fat-free mass, and appendicular lean mass were explored in acute lymphoblastic leukemia (ALL) survivors (n=75; 41 males; 45 standard risk ALL) >10 years from diagnosis. Dual energy radiograph absorptiometry performed body composition analysis. Relationships were assessed by regression analyses and Pearson correlation coefficients (r). Twenty subjects (26.3%) were osteopenic; lumbar spine (LS) BMD Z score <-1.00. Age at diagnosis, sex, ALL risk-category, type of post-induction steroid or cranial radiation did not correlate with LS or whole body (WB) BMD. Body mass index correlated significantly with LS BMD (r=0.333, P=0.004) and WB BMD (r=0.271, P=0.033). FM index (FM/height²) Z score showed no significant correlation with LS or WB BMD. Fat-free mass index Z score correlated strongly with LS BMD (r=0.386, P=0.013) and WB BMD (r=0.605, P<0.001) in males but not in females. The appendicular lean mass index, a surrogate for skeletal muscle mass, correlated significantly with LS BMD (r=0.367, P=0.018) and WB BMD (r=0.604, P<0.001) in males but not in females. Future studies to evaluate interventions to enhance BMD focused on improving body composition particularly skeletal muscle mass are warranted.

Late Effects of Therapy in Childhood Acute Lymphoblastic Leukemia Survivors

Over the last 50 years, the survival rates in children with acute lymphoblastic leukemia (ALL) have increased remarkably. The optimal use of antileukemic agents in cooperative group protocols, central nervous system-directed treatment, improvements in supportive care, and recognition of biological, clinical, and treatment response characteristics that predict patients with a higher or a lower risk of treatment failure have improved 5-year event-free survival rates, reaching more than 85%, and 5-year overall survival rates, reaching more than 90%. Consequently, it has become increasingly important to characterize the occurrence of long-term late effects. ALL treatments have been associated with increased risks for adverse outcomes such as late mortality, secondary malignancies, and neurological, cardiac, endocrine, and social/psychological disorders. In recent decades, cooperative groups in Europe and in the United States have provided essential information about the long-term effects of ALL therapy, giving recommendations for screening as well as facilitating new approaches for reducing late-term morbidity and mortality. Current frontline protocols continue to examine ways to lower the intensity and amount of therapy to reduce late effects, whereas survivorship studies attempt to predict such adverse effects precisely and develop targeted prevention and treatment strategies.

AVALIAÇÃO DOS EFEITOS ÓSSEOS TARDIOS E COMPOSIÇÃO CORPORAL DE CRIANÇAS E ADOLESCENTES TRATADOS DE LEUCEMIA LINFOIDE AGUDA SEGUNDO PROTOCOLOS BRASILEIROS

Objective:

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.

Bone mineral density in children with acute leukemia and its associated factors in Iran: a case-control study

Acute leukemia is the most common malignancy in children. We showed that low bone mass is prevalent among children with leukemia, especially in femur. Serum calcium, exercise, chemotherapy protocol, and radiotherapy are the main contributing factors. We suggest that early diagnosis and treatment of this problem could improve bone health in them.

INTRODUCTION

Acute leukemia is the most common malignancy in children and has been reported to be associated with low bone mass. Due to lack of sufficient data about the bone mineral density of children with leukemia in the Middle East, and inconsistencies between possible associated factors contributing to decreasing bone density in these children, we aimed to conduct a case-control study in Iran.

MATERIALS AND METHODS

This case-control study was conducted on 60 children with acute leukemia and 60 age- and sex-matched healthy controls. Anthropometric data, sun exposure, puberty, physical activity, and mineral biochemical parameters were assessed. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DEXA). Data analysis was done by SPSS software v. 21.

RESULTS

Serum calcium was higher in the control group (P = 0.012) while serum phosphorous, alkaline phosphatase, and serum 25(OH)D₃ were higher in children with leukemia with P values of 0.04, 0.002, and 0.036, respectively. Sun exposure and physical activity were more in healthy controls (P values <0.001 and 0.003, respectively). Prevalence of vitamin D deficiency in case and control groups was 57.8 and 79.4 %, respectively. This prevalence was higher in healthy controls (P value = 0.007). Both lumbar and femoral neck bone mineral apparent density (BMAD) were higher in the control group (P value <0.001). Serum calcium, physical activity, and radiotherapy were the most relevant factors associated with lumbar BMAD. Femoral neck BMAD was associated with chemotherapy protocol.

CONCLUSION

Low bone mass for chronological age is prevalent among children with leukemia, especially in the femoral neck. Serum calcium, physical activity, chemotherapy protocol, and radiotherapy are the main contributing factors.

Young age at diagnosis, male sex, and decreased lean mass are risk factors of osteoporosis in long-term survivors of osteosarcoma

BACKGROUND

Long-term survival of children with osteosarcoma has increased, but most suffer from osteoporosis in adulthood. The aim of this study was to investigate the prevalence and identify the risk factors of osteoporosis.

METHODS

Forty long-term survivors of osteosarcoma and 55 controls were enrolled. The mean age of the survivors was 21.8 ± 5.2 years. They were diagnosed at younger than 23 years of age (mean, 14.9 + 5.0 y). Bone mineral densities (BMD) and body compositions were measured by dual-energy x-ray absorptiometry.

RESULTS

Nineteen (47.5%) subjects had osteoporosis and 12 (30.0%) had osteopenia. The regions affected by osteoporosis were: femur neck of osteosarcoma site (47.5%), unaffected femur neck (12.5%), lumbar spine (12.5%), and total body (15.0%). Twelve subjects (30.0%) had 14 episodes of fractures. The identified risk factors of osteoporosis were young age at diagnosis, male sex, and low lean mass. Subjects diagnosed before attainment of puberty (male ≤ 16 y, female ≤ 14 y) were found to have a higher prevalence of osteoporosis (37.5% vs. 10.0%, P < 0.01). Males had a higher prevalence of osteopenia or osteoporosis than females (86.4% vs. 66.7%, P < 0.01). Total lean mass was positively correlated with unaffected femur neck BMD. Regional lean mass in affected limb was significantly reduced along with affected femur neck BMD.

CONCLUSIONS

In long-term survivors of osteosarcoma, prevalence of osteoporosis and fracture was higher than expected. Initial evaluation and regular follow-up of BMD should be performed in all osteosarcoma patients, especially in those who did not attain puberty, males, and those with a low lean mass.

Risk factors for osteoporosis in long-term survivors of intracranial germ cell tumors

SUMMARY

We measured bone mineral densities in 28 intracranial germ cell tumor long-term survivors. There was the high prevalence of osteoporosis and osteopenia, 25.0% and 42.9%, respectively, and three additional risk factors, male sex, a low lean mass, and adult growth hormone replacement, were identified.

INTRODUCTION

Intracranial germ cell tumor long-term survivors (iGCTLS) have many risk factors for osteoporosis, including irradiation from cancer therapy and multiple hormone deficiencies. However, no study of bone mineral density (BMD) has been conducted in iGCTLS because these tumors are rare. The aims of this study were to evaluate the prevalence of osteoporosis and to identify risk factors associated with reduced bone mass in iGCTLS.

METHODS

We evaluated BMD and body composition of 28 iGCTLS (10.9 ± 5.2 years after cancer treatment; 13 males) using dual-energy X-ray absorptiometry. To determine risk factors, we analyzed the medical history, including the nature of the tumor, treatment modality, endocrine status, hormone replacement therapy, lifestyle, and biochemical parameters.

RESULTS

Twenty-five percent of iGCTLS were diagnosed with osteoporosis and 42.9% with osteopenia. Most males (92.3%) had low BMD. Lean mass (LM) was positively correlated with BMD in all regions of interest, and the starting age of adult growth hormone (GH) replacement was negatively correlated with the BMD Z-score at the femur neck. In logistic regression analysis, male sex and low LM were related to low BMD.

CONCLUSIONS

The iGCTLS had a high prevalence of low BMD. We found that male sex, low LM, and delayed start of adult GH replacement were risk factors for osteoporosis. Therefore, the BMD of all iGCTLS should be evaluated, and if it is low, proper management should be started early.

Little evidence of low bone mass in acute lymphoblastic leukemia survivors

Childhood acute lymphoblastic leukemia (ALL) survivors represent a specific group at risk for many health problems, including skeletal complications and osteoporosis. The objective of this study was to assess the risk of osteoporosis associated with the prevalence of low bone mass (according to the guidelines of the Pediatric Official Positions of the International Society for Clinical Densitometry 2007) in survivors of childhood ALL. The cross-sectional study was conducted in a cohort of 69 Caucasian children and adolescents (46 boys and 23 girls) aged 12.15 ± 0.5yr diagnosed with ALL and screened up to 5 yr after cessation of the treatment. Total body bone mineral content (TB BMC, g), total body bone mineral density (TB BMD, g/cm(2)), and lumbar spine BMD (LS BMD, g/cm(2)) were determined using dual-energy X-ray absorptiometry. Time interval from the completion of the treatment to the beginning of this study (subgroup I<2 yr or subgroup II>2 yr after treatment), methotrexate (MTX) doses (subgroup I-MTX ranging from 0.5 to 1.0g/m(2); subgroup II-MTX>2.0 g/m(2)), cranial irradiation (subgroup I-without radiotherapy (RTX) and subgroup II receiving RTX of 12-18 Gy), cumulative steroid dose, and impaired endocrine function were considered as potential factors affecting bone metabolism and included in the analysis. No differences were found in bone traits (BMC, TB BMD, LS BMD) in relation to examined risk factors. In multiple regression model that included therapeutical factors, a risk group and central nervous system irradiation were of an important influence on bone mass, and risk group predicted TB BMD in small degree. Risk group and irradiation status lost their significance after the inclusion of anthropometric, age-connected, and time-connected factors. This study suggests that ALL survivors are not at increased risk for low bone mass. However, from the clinical perspective all patients after childhood ALL should be screened for clinical signs, fracture history, and lifestyle risk factors for low bone mass and osteoporosis. They should be referred to bone density evaluation only as often as may be necessary from the clinical evaluation.

Is the treatment for childhood solid tumors associated with lower bone mass than that for leukemia and Hodgkin disease?

BACKGROUND

Cancer disease and its therapy (e.g., chemotherapeutic agents such as glucocorticoids, methotrexate, antymetabolities, cranial and local irradiation) may severely disturb normal growth, bone mineral acquisition, and skeletal development because most individuals go through the stages of rapid growth when childhood cancer is diagnosed.

PROCEDURES

To identify factors associated with reduced bone mineral density (BMD) in survivors of childhood cancer the authors examined 114 patients (70 males) who had been treated for acute lymphoblastic leukemia (ALL; n = 43), Hodgkin disease (HD; n = 35), and solid tumors (ST; n = 36) twice. Median age at diagnosis was 8.4 years; at the consecutive examinations it was 12.8 and 16.3 years, respectively. To assess bone density we used dual-energy x-ray absorptiometry (DXA).

RESULTS

In the first examination, patients with a history of steroid therapy had higher total and spine BMD and higher BMI (body mass index) than those who were not given steroids. At the end of the follow-up, no differences were found in BMD between subgroups, although BMI was still higher in both ALL and HD patients than in those with ST.

CONCLUSIONS

Patients treated for solid tumors have reduced bone mass. Low BMI and local irradiation seem to be the factors responsible for reduced BMD in children treated for ST. The use of steroids does not disturb bone mass accumulation in patients treated for childhood malignancies. However, a long-term effect of cancer treatment on osteoporosis risk remains to be determined.