Bone mineral density in children with acute lymphoblastic leukaemia

Bone health in glucocorticoid-treated childhood acute lymphoblastic leukemia

Glucocorticoids (GCs) are widely used in the treatment of childhood acute lymphoblastic leukemia (ALL), but their long-term use is also associated with bone-related morbidities. Among others, growth deficit, decreased bone mineral density (BMD) and increased fracture rate are well-documented and severely impact quality of life. Unfortunately, no efficient treatment for the management of bone health impairment in patients and survivors is currently available. The overall goal of this review is to discuss the existing data on how GCs impair bone health in pediatric ALL and attempts made to minimize these side effects.

Home-Based Telehealth Exercise Intervention in Early-On Survivors of Childhood Acute Lymphoblastic Leukemia: Feasibility Study

Background

Acute lymphoblastic leukemia is the most common type of pediatric cancer. Acute lymphoblastic leukemia causes an altered bone mineral homeostasis state, which can contribute to osteopenia, and bone fractures, most commonly vertebral fractures. With the increasing number of childhood cancer survivors, late adverse effects such as musculoskeletal comorbidities are often reported and are further influenced by inactive lifestyle habits. Physical activity has been shown to increase the mechanical workload of the bone, mitigating bone impairment in other cancer-specific populations.

Objective

This interventional pilot study aims to investigate the use of telehealth to deliver a home-based exercise intervention for early-on survivors of bone marrow–related hematological malignancies and to assess its impact on survivors’ musculoskeletal and functional health.

Methods

We aimed to recruit a group of 12 early-on survivors of acute lymphoblastic leukemia, within 6 months to 5 years of treatment, to participate in and complete the proposed telehealth intervention with a parent. The 16-week intervention included 40 potential home-based physical activity interventions supervised by a kinesiologist through a telehealth internet platform, with monthly progression. Patients were recruited to the cohort if they were able to participate in the intervention during the first month (minimum 12 weeks of intervention). Evaluation before and after the intervention protocol highlighted differences in functional capacities and musculoskeletal health of patients using mechanography, peripheral quantitative computed tomography, 6-minute walk test, and grip force test.

Results

The recruitment rate for the intervention was low (12/57, 21% of contacted patients). Of 12 patients, 3 were excluded (1=relapse, 1=failure to meet technical requirements, and 1=abandoned). The 9 patients who completed the intervention (6 girls; mean age 10.93, SD 2.83 years; mean BMI 21.58, SD 6.55 kg/m²; mean time since treatment completion 36.67, SD 16.37 months) had a mean adherence of 89% and a completion rate of 75%. In addition, these patients showed functional improvements in lower limb muscle force and power as well as in the 6-minute walk test distance. Participants also showed improved bone health after the intervention on the following parameters: bone mineral content, stress-strain index, total and cortical cross-sectional area at the 14% site (P=.03, P=.01, P=.01, and P=.001, respectively) and 38% site of the tibia (P=.003, P=.04, P=.001, and P=.003, respectively).

Conclusions

High adherence and participation rates suggest that telehealth is a feasible method to deliver exercise interventions to young early-on survivors of acute lymphoblastic leukemia. The proposed intervention seems promising in providing benefits to patients’ functional performance and bone health, but a large-scale study is needed to confirm this assumption.

Vitamin D supplementation for children with cancer: A systematic review and consensus recommendations

Background

Prevalent vitamin D deficiency (VDD) and low bone mineral density (BMD) have led to vitamin D supplementation for children with cancer, regardless vitamin D status. However, it remains unsettled whether this enhances bone strength. We sought to address this issue by carrying out a systematic review of the literature.

Methods

We conducted a literature search using PubMed, Embase, and Cochrane databases. Studies including children up to 5 years after cancer therapy were assessed for the association between 25‐hydroxyvitamin D (25OHD) levels and BMD Z‐scores or fractures, and the effect of vitamin D supplementation on BMD or fractures. Evidence quality was assessed using the GRADE methodology.

Results

Nineteen studies (16 observational and 3 interventional, mainly involving children with hematologic malignancies) were included. One study which analyzed 25OHD as a threshold variable (≤10 ng/ml) found a significant association between 25OHD levels and BMD Z‐scores, while 25OHD as a continuous variable was not significantly associated with BMD Z‐scores in 14 observational studies. We found neither a significant association between lower 25OHD levels and fractures (2 studies), nor between vitamin D (and calcium) supplementation and BMD or fracture frequency (3 studies) (very low quality evidence).

Conclusion

There is a lack of evidence for an effect of vitamin D (and calcium) supplementation on BMD or fractures in children with cancer. Further research is needed; until then, we recommend dietary vitamin D/calcium intake in keeping with standard national guidelines, and periodic 25OHD monitoring to detect levels <20 ng/ml. Vitamin D/calcium supplementation is recommended in children with low levels, to maintain levels ≥20 ng/ml year‐long.

Prevalence of Osteopathologies in Children and Adolescents After Diagnosis of Acute Lymphoblastic Leukemia

Background: Impaired bone health is a late effect of childhood malignancies which can be difficult to detect in juvenile survivors. It may, however, lead to compromised quality of life, or even permanent disability later in life due to osteoporosis, pain or fractures if left untreated. Acute lymphoblastic leukemia (ALL) is the most frequent childhood malignancy with an over 85% five-year survival. ALL and its treatment cause bone alterations in adults, but little information on the bone health status in juvenile survivors is available. Objective: To report data on skeletal late effects in juvenile survivors of childhood ALL based on a comprehensive assessment of bone health and to assess the influence of a vitamin D deficiency on bone health in this cohort. Methods: In a single center cross sectional study 128 pediatric patients (11.9 ± 4.76 years) with a mean follow up of 5.88 ± 3.75 years after diagnosis of ALL were recruited. The bone health status of the survivors was assessed based on clinical examination, review of medical records, biochemical and radiographic analyses, by clinical experts. A score which utilized 8 different parameters was formed and used to assess the effect of a vitamin D deficiency on bone health. Results: In this cohort, 18% of survivors displayed overt osteopathologies as defined by clinical expert assessment. Impaired bone health, defined by at least one pathological screening parameter, was detected in 77%. Despite recommendations for adequate vitamin D supplementation, 15% displayed a vitamin D deficiency associated with hyperparathyroidism. The applied score identified survivors with osteopathologies with high sensitivity and specificity. The median score did not differ between patients without and with severe vitamin D deficiency. Conclusion: Our findings suggest that impaired bone health and osteopathologies are common skeletal late effects following treatment of childhood ALL. Major contributing factors are BMT, irradiation and older age at diagnosis. Vitamin D deficiency likely accounts for hyperparathyroidism in some patients but does not seem to further affect bone health in this cohort. Survivors of ALL need thorough surveillance to investigate bone health, since bone morbidity is common and still poorly understood. Early detection and appropriate intervention may improve bone health.

Low bone mineral density is associated with hypogonadism and cranial irradiation in male childhood cancer survivors

We investigated if bone mineral density was related to testosterone deficiency and/or previous cancer treatment in men who were childhood cancer survivors. Men with untreated testosterone deficiency or previous treatment with cranial irradiation were at increased risk of impaired bone health. Prevention of osteoporosis should be considered in their follow-up.

INTRODUCTION

Childhood cancer survivors (CCS) are at increased risk of hypogonadism. Reduced bone mineral density (BMD) has been reported in CCS but it is unclear whether this is due to hypogonadism or a direct effect of cancer therapy. This study investigated BMD in CCS, and association with hypogonadism, previous treatment and cancer type.

METHODS

Investigation of 125 CCS (median age 33.7 at inclusion; 9.6 at diagnosis) and 125 age-matched population controls. Serum testosterone and luteinizing hormone were assayed and BMD at total hip and lumbar spine L1-L4 measured. The mean difference in BMD (g/cm²; 95% CI) between CCS and controls was analysed. Odds ratios (OR; 95% CI) for low BMD were also calculated.

RESULTS

Overall, BMD in the CCS cohort did not significantly differ from controls. However, compared with eugonadal CCS, the CCS with untreated hypogonadism had lower BMD at the hip (mean difference - 0.139 (- 0.210; - 0.067); p < 0.001) and spine (- 0.102 (- 0.174; - 0.030); p = 0.006). They also had a higher risk of low hip BMD (OR 4.1 (1.3; 14); p = 0.018). CCS treated with cranial irradiation also had lower BMD (hip - 0.076 (- 0.133; - 0.019); p = 0.009; spine - 0.071 (- 0.124; - 0.018); p = 0.009) compared with controls. The latter associations remained statistically significant after adjustment for hypogonadism.

CONCLUSIONS

CCS with hypogonadism or previously treated with cranial irradiation are at increased risk of impaired bone health. Prevention of osteoporosis should be considered as an important part in future follow-up of these men.

Health-related fitness in very long-term survivors of childhood cancer: A cross-sectional study

BACKGROUND

Impairment of health-related physical fitness (HRPF) in survivors of acute lymphoblastic leukemia has been shown. However, evidence of impairment in survivors of other pediatric malignancies and possible risk factors is limited.

PARTICIPANTS AND METHODS

HRPF of 17 survivors of pediatric acute myeloid leukemia (AML), 26 survivors of neuroblastoma (NBL), 28 survivors of Wilms tumor (WT) (median age 28.8 [18.8-62.6] years) after a median follow-up time of 24.5 (6.5-43.6) years, and 74 healthy controls (median age 26.9 [17.9-61.7] years). Risk factors were investigated. Testing included submaximal cardiovascular endurance (6-Minute Walk Test (6 MWT), flexibility, and muscle strength.

RESULTS

Results are expressed as mean (standard error). Survivors scored significantly lower than controls on the 6 MWT (588 ± 6.1 m vs. controls 611 ± 6.0 m; P = 0.008), on side flexion of the trunk (20.1 ± 0.4 cm vs. controls 22.4 ±0.4 cm; P < 0.001), and on vertical jump (39.7 ± 0.8 cm vs. controls 43.8 ± 0.8 cm; P < 0.001). Survivors of AML had lower scores on the 6 MWT (563 ± 12.4 m) than survivors of NBL (585 ± 9.9 m) and survivors of WT (606 ± 9.6 m), P = 0.046. Being a survivor, higher body mass index (BMI) and no participation in sports were independently associated with lower scores on the 6 MWT.

CONCLUSION

Survivors of NBL, WT, and especially AML have impaired HRPF. Higher BMI and physical inactivity at adult age appeared prominent risk factors for impaired HRPF in these survivors.

Bone Health in Patients With Hematopoietic Disorders of Bone Marrow Origin: Systematic Review and Meta- Analysis

Blood cell production and bone homeostasis are physically interlinked systems that exhibit active cross-talk. We examined how bone health is affected in patients with hematopoietic disorders due to abnormal proliferation of bone marrow cells. The electronic databases Medline, Embase, PubMed, BIOSIS Previews, Web of Science, and Cochrane were searched for studies presenting numerical values for trabecular bone volume or bone mineral density in control and patients with hematopoietic disorders. We identified 5 studies for beta-thalassemia, 6 for sickle cell anemia, 2 for polycythemia vera and essential thrombocythemia, 3 for chronic myelogenous leukemia, 6 for myelofibrosis, 5 for multiple myeloma, and 4 studies each for systemic mastocytosis, lymphocytic leukemia, and hemochromatosis. The effect of the disease state on bone density was significant and negative for beta-thalassemia (r = -2.00; 95% confidence interval [CI] -3.41, -0.58; p < 0.005), sickle cell anemia (-0.91; -1.36, -0.47; p < 0.00005), chronic myelogenous leukemia (-0.55; -0.88, -0.22; p < 0005), mastocytosis (-0.99; -1.16, -0.82; p < 0.00001), lymphoblastic leukemia (-0.69; -0.98, -0.40; p < 0.00001), multiple myeloma (-0.67; -0.99, -0.35; p < 0.00005), and hemochromatosis (-1.15; -1.64, -0.66; p < 0.00001). The changes were negative but not significant for polycythemia vera (-0.16; -0.38, 0.05; p = 0.069) and essential thrombocythemia (-0.33; -0.92, 0.26; p = 0.14). In myelofibrosis, disease state was associated with increased bone density (0.74; 0.12, 1.36; p < 0.05). Bone density change significantly and negatively correlated with the level of ferritin and bone marrow cellularity but not with hemoglobin or erythropoietin. Thus, independent of hematopoietic lineage, abnormal proliferation of bone marrow cells appears to be associated with bone loss. Iron metabolism may independently contribute to bone homeostasis. © 2016 American Society for Bone and Mineral Research.

Bone Mineral Density in Survivors of Childhood Acute Lymphoblastic Leukemia

Background:

The objective of this study was to evaluate bone mineral density (BMD) after completion of treatment for childhood acute lymphoblastic leukemia (ALL).

Methods:

In this cross-sectional study, 103 survivors of ALL aged 13.5 ± 0.45 who completed their treatment at least one year earlier were enrolled. Among these, 49.5% and 51.5% received chemotherapy alone and chemotherapy plus cranial radiotherapy, respectively. Bone mineral content, BMD, and bone mineral apparent density in the lumbar spine (LS), femoral neck (FN) and forearm were assessed using dual-energy X-ray absorptiometry (DEXA). BMD Z-scores were classified according to International Society for Clinical Densitometry (ISCD) criteria.

Results:

The mean BMD Z-scores ± SD forLS, FN and forearm were -1.60 ± 0.12, -1.21 ± 0.9 and -2.43 ± 0.14 respectively with significant differences (P<0.001). Considering the lowest BMD Z-score in LS and FN areas (at any site) and according to the ISCD classification, 62.1%, 33% and 4.9% of the patients had normal BMD, low BMD and osteoporosis, respectively. Also, 8.7% of patients had developed fractures after completion of the treatment period, 4.9% having BMD Z-Scores <-2 SD at any site. A direct relationship was apparent between BMD Z-scores at LS and FN at any sites and risk of fracture (P<0.001).

Conclusions:

ALL patients are at risk for low BMD and fracture. Therefore, applying DEXA scanning is recommended after completion of therapy for prevention of BMD reduction and osteoporosis.

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.

Comparison of mandibular cortical thickness and QCT-derived bone mineral density (BMD) in survivors of childhood acute lymphoblastic leukemia: a retrospective study

OBJECTIVE

To examine whether panoramic radiograph-determined mandibular cortical thickness correlated with quantitative computed tomography-derived bone mineral density (BMD) in survivors of childhood acute lymphoblastic leukemia (ALL).

METHODS

We identified patients treated for ALL at St. Jude Children's Research Hospital, seen in the After Completion of Therapy (ACT) Clinic between January of 2006 and January of 2014 who had QCT-derived BMD and panoramic radiographs obtained within 1 month of each other. Panoramic radiographs were independently scored by a pediatric radiologist, two pediatric dentists, and a general dentist using the Klemetti technique. We used the Spearman's rank correlation test and the multivariate regression model to investigate the effect of evaluator experience on results.

RESULTS

The study cohort comprised 181 patients with 320 paired studies: 112 (62%) male, 112 (71%) were white. Median age at ALL diagnosis was 6.4 (range, 0-18.8) years. Median age at study was 11.9 (range, 3.3 to 29.4) years. The median average BMD was 154.6 (range, 0.73-256) mg/cc; median QCT Z-score (age and gender adjusted) was -0.875 (range, -5.04 to 3.2). We found very weak association between panoramic radiograph score and both QCT-BMD average (P = 0.53) and QCT Z-score (P = 0.39). Results were not influenced by level of reader experience.

CONCLUSIONS

The Klemetti technique of estimating BMD does not predict BMD deficits in children and young adult survivors of ALL, regardless of reviewer expertise. Alternative methods are needed whereby dental healthcare providers can identify and refer patients at risk for BMD deficits for detailed assessment and intervention.

The Incidence of and Factors Associated with Vitamin D Deficiency in Newly Diagnosed Children with Cancer

This retrospective chart review study aimed to assess vitamin D status and identify risk factors associated with vitamin D deficiency and bone parameters in children with cancer at admission. The data of 86 (50 males and 36 females) patients between April 2013 and June 2015 were analyzed. Calcium, phosphorus, alkaline phosphatase (ALP), 25(OH)D, age, gender, diagnostic category, body mass index, duration of complaints, and season of blood sampling were recorded. Median age was 7.17 years (range 0.31-17.40) in 29 hematological malignancy and 57 solid tumor patients. According to cut-off level of 20 ng/ml, 63% of children with cancer had vitamin D deficiency at diagnosis with a median 25(OH)D of 16.75 ng/ml. The mean vitamin D value of children >10 years was significantly low in comparison to that observed in younger children [11.83, 95% confidence interval (CI) = = 8.85-14.81 ng/ml vs. 19.81, 95% CI = = 17.02-22.60 ng/ml]. Vitamin D measurement between November and May was a risk factor for vitamin D deficiency (P < 0.05). The frequency of hypocalcemia and hypophosphatemia was not different between two groups of vitamin D. Further longitudinal studies are needed to investigate whether monitoring vitamin D status and supplementation in children with cancer might prevent future complications related to vitamin D deficiency.

Early injury to cortical and cancellous bone from induction chemotherapy for adolescents and young adults treated for acute lymphoblastic leukemia

Diminished bone density and skeletal fractures are common morbidities during and following therapy for acute lymphoblastic leukemia (ALL). While cumulative doses of osteotoxic chemotherapy for ALL have been reported to adversely impact bone density, the timing of onset of this effect as well as other changes to bone structure is not well characterized. We therefore conducted a prospective cohort study in pre-adolescent and adolescent patients (10-21years) newly diagnosed with ALL (n=38) to explore leukemia-related changes to bone at diagnosis and the subsequent impact of the first phase of chemotherapy ("Induction"). Using quantitative computerized tomography (QCT), we found that pre-chemotherapy bone properties were similar to age- and sex-matched controls. Subsequently over the one month Induction period, however, cancellous volumetric bone mineral density (vBMD) decreased markedly (-26.8%, p<0.001) with sparing of cortical vBMD (tibia -0.0%, p=0.860, femur -0.7%, p=0.290). The tibia underwent significant cortical thinning (average cortical thickness-1.2%, p<0.001; cortical area-0.4%, p=0.014), while the femur was less affected. Areal BMD (aBMD) concurrently measured by dual-energy X-ray absorptiometry (DXA) underestimated changes from baseline as compared to vBMD. Biochemical evidence revealed prevalent Vitamin D insufficiency and a net resorptive state at start and end of Induction. Our findings demonstrate for the first time that significant alterations to cancellous and cortical bone develop during the first month of treatment, far earlier during ALL therapy than previously considered. Given that osteotoxic chemotherapy is integral to curative regimens for ALL, these results provide reason to re-evaluate traditional approaches toward chemotherapy-associated bone toxicity and highlight the urgent need for investigation into interventions to mitigate this common adverse effect.

The Progression of Bone Mineral Density Abnormalities After Chemotherapy for Childhood Acute Lymphoblastic Leukemia

Although reduced bone mineral density in survivors of childhood acute lymphoblastic leukemia (ALL) is well documented, the degree of demineralization and relation to age are not well described. This is a retrospective chart analysis of 58 patients consecutively treated for ALL without relapse, cranial irradiation, or transplantation. Bone mineral densities were measured by dual-energy x-ray absorptiometry and patients were divided by sex and age (≤5, 6 to 10, and >10 y) at diagnosis. Serial scans for 6 years after therapy were analyzed as Z-scores. Over 6 years after therapy, 93.1% of patients exhibited a decreased Z-score in at least 1 anatomic site. The difference in Z-score among the age cohorts was significant at both the lumbar spine and femoral neck. Patients older than 10 years at diagnosis had the lowest Z-scores: -2.78 and -2.87 for boys and -2.39 and -2.91 for girls at the lumbar spine and femoral neck, respectively. Children after ALL therapy exhibit a significant bone mineral deficit shortly after completion of therapy that persists for at least 6 years. The degree of bone demineralization can be followed up by a dual-energy x-ray absorptiometry scan and is most severe in patients older than 10 years at the initiation of therapy.

Bone morbidity in childhood leukemia: epidemiology, mechanisms, diagnosis, and treatment

Skeletal abnormalities are commonly seen in children and adolescents with leukemia. The spectrum ranges from mild pain to debilitating osteonecrosis (ON) and fractures. In this review, we summarize the skeletal manifestations, provide an update on therapeutic strategies for prevention and treatment, and discuss the most recent advances in musculoskeletal research. Early recognition of skeletal abnormalities and strategies to optimize bone health are essential to prevent long-term skeletal sequelae and diminished quality of life observed in children and adolescents with leukemia.

Aleukaemic leukaemia presenting with pathological fracture

A 19-month-old Chinese girl presented with pathological fracture of her right distal tibia. Peripheral blood revealed no abnormal cells, electrolytes were normal and bone biopsy at the fracture site only showed small aggregates of unremarkable lymphocytes. A bone marrow study could not provide a definitive diagnosis of acute leukaemia on morphology and immunohistochemistry. A diagnosis of precursor B-cell acute lymphoblastic leukaemia was unequivocally confirmed by a cytogenetic study which showed a hyperdiploid clone with gain of chromosome 4 among other trisomies.

Motor performance and functional exercise capacity in survivors of pediatric acute lymphoblastic leukemia

BACKGROUND

Impaired motor performance and reduced maximum exercise capacity during and after treatment of acute lymphoblastic leukemia (ALL) has been shown. However, no longitudinal study monitoring motor performance after cessation of treatment has been published. Whether sub-maximal exercise capacity is reduced is unknown.

PROCEDURE

Motor performance of pediatric ALL survivors, treated with Dutch Childhood Oncology Group ALL-9 protocol was measured with the movement-ABC at stop treatment and ≥5 years later. At follow-up functional exercise capacity was also investigated using the 6-minute walk test (6MWT). Heart rate and oxygen saturation were measured with a portable pulse oximeter before and after the 6MWT.

RESULTS

Nineteen boys and 15 girls, median age 12.3 years (range: 9.0-18.7), median time since completion of chemotherapy 5.2 years (5.0-7.1), participated. Mean height/age and weight/age were within the norm, whereas mean BMI/age was significantly increased (mean SDS 0.38, SEM 0.17, P = 0.04). Motor performance had improved significantly (P = 0.001). In contrast, functional exercise capacity at follow-up was significantly impaired (mean SDS -2.05, SEM 0.13, P < 0.001).

CONCLUSIONS

At ≥5 years after completion of ALL treatment motor performance had improved significantly, but functional exercise capacity was significantly impaired. The exact underlying cause of this late effect needs further study.

Germline variation in the MTHFR and MTRR genes determines the nadir of bone density in pediatric acute lymphoblastic leukemia: a prospective study

BACKGROUND

This study aims to identify folate-metabolism-related genetic risk factors for low bone mineral density (BMD) during/after pediatric acute lymphoblastic leukemia (ALL) treatment.

PATIENTS AND METHODS

We investigated the influence of methylenetetrahydrofolate reductase (MTHFR 677C > T and 1298A > C) and methionine synthase reductase (MTRR 66A > G) single nucleotide polymorphisms (SNPs) on total body BMD (BMD(TB)) and lumbar spine BMD (BMD(LS)) in 83 patients. Homocysteine, folate and vitamin B12 were determined. BMD was measured repeatedly using dual-energy X-ray absorptiometry in patients ≥ 4 years (n = 68).

RESULTS

Carriers of the MTHFR 677 T-allele showed a lower baseline BMD(TB) than non-carriers (-0.38 SDS vs. +0.55 SDS, p = 0.01) and BMD(TB) remained lower during/after treatment. MTHFR 677C>T did not influence treatment-related loss of BMD(TB) (p = 0.39). The MTRR 66 G-allele carriers showed a trend towards a lower BMD(TB) compared with non-carriers. Combining these two SNPs, patients carrying ≥ 2 risk alleles had a significantly lower BMD(TB) (-1.40 SDS) than patients with one (-0.80 SDS) or no risk alleles (-0.31 SDS). Although carriers of the MTHFR 1298A > C had higher homocysteine levels, this SNP was not related to BMD(TB). BMD(LS) of carriers was similar to non-carriers of the investigated SNPs.

CONCLUSIONS

The MTHFR 677C>T SNP and the MTRR 66A >G SNP were identified as determinants of impaired BMD(TB) in childhood ALL patients.

Prospective bone ultrasound patterns during childhood acute lymphoblastic leukemia treatment

OBJECTIVE

Bone impairment is a well-known complication in childhood acute lymphoblastic leukemia (ALL) survivors but less is known about bone dynamics during ALL therapy. We longitudinally assessed by Quantitative Ultrasound (QUS) skeletal modifications during this treatment.

MATERIALS AND METHODS

Forty-four newly diagnosed ALL children underwent bone measurement by QUS parameters BTT (Bone Transmission Time) and AD-SoS (Amplitude-Dependent Speed of Sound), mainly reliant on bone density and cortical thickness, respectively. Measurements were performed at diagnosis, and 6, 12, and 24 months thereafter. The occurrence of skeletal complications such as fractures, vertebral collapse, osteonecrosis, and osteopenia was related to measurement outcome.

RESULTS

A rapid deterioration of bone properties measured by BTT and AD-SoS was evident in the first semester of therapy (p<0.001). Subsequently, the next measurements were characterized by progressive uncoupling of the two QUS parameters (p<0.001). These were both significantly reduced at the end of therapy (p<0.001). Twelve subjects with in-treatment skeletal complications displayed an almost two-fold decrease of both parameters (p<0.001). BTT decreasing more than 1 Standard Deviation (SD) over 6 months of therapy was able to predict skeletal complication occurrence (p<0.001).

CONCLUSION

This report represents the largest longitudinal cohort systematically submitted to bone condition assessment from the beginning to the end of therapy for childhood ALL. Bone deterioration occurs early and persists throughout therapy, consistent with bone properties uncoupling. This pattern possibly reflects an initial impairment of both mineral density and cortical thickness with a subsequent recovery of this latter. QUS permits an early detection of bone deterioration and related skeletal complications in childhood ALL.

Pharmacogenetic risk factors for altered bone mineral density and body composition in pediatric acute lymphoblastic leukemia

BACKGROUND

This study investigates pharmacogenetic risk factors for bone mineral (apparent) density (BM(A)D) and body composition in pediatric acute lymphoblastic leukemia

DESIGN AND METHODS

We determined the influence of SNPs in 4 genes (vitamin-D receptor (VDR: BsmI/ApaI/TaqI and Cdx-2/GATA), collagen type I alpha 1 (SpI), estrogen receptor 1 (ESR1: PvuII/XbaI), glucocorticoid receptor (BclI)) on body composition, BM(A)D and fracture risk during dexamethasone-based pediatric acute lymphoblastic leukemia treatment. Body composition and BMD were measured repeatedly during and after treatment using dual energy X-ray absorptiometry.

RESULTS

Non-carriers of VDR 5'-end (Cdx-2/GATA) haplotype 3 revealed a significant larger fat gain than carriers (Delta%fat: non-carriers: +1.76SDS, carriers: +0.77SDS, P<0.001). At diagnosis and during therapy, lumbar spine BMD was significantly higher in non-carriers of VDR 5'-end (Cdx-2/GATA) haplotype 3 than in carriers. The other SNPs did not influence BMD or fracture risk during/after treatment. The year after treatment completion, lean body mass increased in non-carriers of ESR1 (PvuII/XbaI) haplotype 3 and decreased in carriers (Delta lean body mass: non-carriers:+0.28SDS, carriers: -0.55SDS, P<0.01).

CONCLUSIONS

Only VDR 5'-end (Cdx-2/GATA) haplotype 3 was identified as protective factor against excessive fat gain and as a risk factor for lower lumbar spine BMD during treatment. Carrying ESR1 (PvuII/XbaI) haplotype 3 negatively influenced recovery of lean body mass after pediatric acute lymphoblastic leukemia treatment.

Modeling pathways for low bone mass in children with malignancies

Children with malignancies have low bone mass. Pathways for metabolic bone disease were investigated in children with cancer by concomitantly assessing lifestyle, clinical, and biochemical predictors of bone mass. Forty-one children who were receiving cancer therapy for 61 weeks and 39 controls were studied. Data on lifestyle factors, biochemical and hormonal parameters, dual-energy X-ray absorptiometry bone mass measurements, body composition, and bone age were obtained. Compared with controls, patients had higher weight percentile and fat mass, a 6-month delay in bone age, and lower estradiol levels. They also had higher parathyroid hormone levels and lower bone remodeling markers and bone mass. Age, height, lean mass, fat mass, and bone maturation correlated positively with several bone mass variables, so did serum estradiol, testosterone, and markers of bone remodeling. Conversely, corticosteroids, methotrexate (MTX), and intrathecal therapy negatively correlated with bone mass at the spine and hip (R = -0.33 to 0.40, p < 0.04). In the adjusted analyses, bone maturation, serum osteocalcin level, MTX, and intrathecal therapy were significant predictors of lumbar spine and total body Z-scores, bone maturation accounting for the largest proportion in Z-score variance. Chemotherapy-induced delay in bone maturation and suppression of bone modeling are major pathophysiologic pathways predicting bone mass in children with malignancies.

A randomized trial investigating an exercise program to prevent reduction of bone mineral density and impairment of motor performance during treatment for childhood acute lymphoblastic leukemia

BACKGROUND

Reduced bone mineral density (BMD), altered body composition, impaired motor performance and passive ankle dorsiflexion are side effects of acute lymphoblastic leukemia (ALL) treatment. We performed a randomized study investigating whether an exercise program could prevent these side effects.

PROCEDURE

At diagnosis we randomized 51 ALL patients (median age: 5.4 years) into a group receiving a 2-year exercise program or a control group receiving standard care. BMD of total body (BMD(TB)), lumbar spine (BMD(LS)) and body composition were measured using dual energy X-ray absorptiometry, motor performance with Bayley Scales of Infant Development or Movement-ABC, and passive ankle dorsiflexion with a goniometer. The investigator was blinded to the randomization.

RESULTS

Body fat increased equally during treatment in both groups. One year after cessation of therapy more rapid decline of excessive body fat was observed in the intervention group than in the controls (P = 0.01). Lean body mass, BMD(TB) and BMD(LS) of both groups decreased equally during treatment and increased equally thereafter. Both groups showed a similar decrease in passive ankle dorsiflexion and motor performance during treatment. Adherence to the intervention program varied considerably. Adherence to intervention: 11% of children exercised daily, 37% > once a week, 16% once weekly, 36% < once a week.

CONCLUSIONS

The exercise program was not more beneficial than standard care in preventing reduction in BMD, motor performance and passive ankle dorsiflexion than standard care, most likely due to unsatisfactory compliance. Increased BMI and body fat in the intervention group normalized faster after cessation of chemotherapy.

Bone mineral density, growth, and thyroid function in long-term survivors of pediatric Hodgkin's lymphoma treated with chemotherapy only

BACKGROUND

The aim of this study was to investigate the long-term side effects of treatment for childhood Hodgkin's lymphoma with chemotherapy only on growth, bone mineral density (BMD), body composition, and thyroid function.

PROCEDURE

A total of 88 patients (56 male, 32 female; 17.6-42.6 yr), treated for childhood Hodgkin's lymphoma from 1974-1998 with combination chemotherapy adriamycin (doxorubicin), bleomycin, vinblastine, and dacarbazine or epirubicin, bleomycin, vinblastine, dacarbazine with or without mechlorethamine, oncovin (vincristine), procarbazine, and prednisone (MOPP) with the intention to avoid radiotherapy, participated in this study. Median follow-up was 15.5 yr (range 5.6-30.2). BMD of lumbar spine and total body (BMD-TB), and body composition were measured using dual-energy x-ray absorptiometry. Bone mineral apparent density of the lumbar spine was calculated to correct for bone size. Free T4 and TSH were measured.

RESULTS

Men treated with MOPP had a significantly reduced height with normal body proportions. Women treated with MOPP had decreased BMD-TB and bone mineral apparent density of the lumbar spine as compared with healthy controls. Percent body fat was significantly increased in female patients treated without MOPP. Body mass index was significantly increased in male patients treated without MOPP, whereas lean body mass was normal in all patients. All patients, except one, treated with chemotherapy only had normal thyroid function. However, five patients who received additional radiation to the thyroid either had abnormal levels of TSH or free T4, or used thyroid hormones.

CONCLUSIONS

Lean body mass was normal in all patients; thyroid function was normal in all but one patient. The use of MOPP leads to decreased height and increased body mass index in men and decreased BMD-TB in women.

Total body bone measurements: a cross-sectional study in children with acute lymphoblastic leukemia during and following completion of therapy

BACKGROUND

Abnormalities in bone mineral density (BMD) occur in children treated for acute lymphoblastic leukemia (ALL). However, BMD estimates have been performed using varied instruments, reference data, and interpretations. This exploratory cross sectional study to evaluate bone mass in children with ALL, uses an algorithm that serially adjusts for variables known to affect pediatric bone measures by dual energy X-ray absorptiometry (DXA), based on models developed in 1,218 healthy children and adolescents.

PROCEDURE

Anthropometry, DXA scans, and factors with possible influence on bone mass were evaluated in 21 ALL patients receiving chemotherapy and 20 in the follow-up phase. Main outcome was treatment group differences in Z-scores for total body bone mineral content (BMC), bone area (Area), and areal BMD (aBMD).

RESULTS

Mean Z-scores for the entire study population for BMC, Area, and aBMD were significantly less than zero. Among possible contributing factors, only calcium intake was a significant co-variate. Comparison between treatment groups showed that least-square mean Z-scores for patients on-therapy for at least 12 months were significantly lower than those off therapy for at least 12 months (P: 0.0008-0.044), except for BMC at last step of the algorithm (adjusted for sex, age, ethnicity, height, weight, and bone area).

CONCLUSIONS

Evaluation of total body DXA by this algorithm is consistent with better general bone status in those off-therapy. However, in this small exploratory study, the lack of significant difference between Z-scores for fully adjusted BMC in on- versus off-therapy groups suggests possible risk of low peak bone mass. Additional longitudinal evaluation is warranted.

Pediatric dual-energy X-ray absorptiometry: technique, interpretation, and clinical applications

This article reviews the dual-energy x-ray absorptiometry (DXA) technique, its interpretation, and clinical applications with emphasis on the considerations unique to pediatrics. Specifically, the use of DXA in children requires the radiologist to be a "clinical pathologist," monitoring the technical aspects of the DXA acquisition, a "statistician" knowledgeable in the concepts of Z-scores and least significant changes, and a "bone specialist," aware of the DXA findings in a large number of clinical diseases, providing the referring clinician with a meaningful context for the numeric result obtained with DXA.

Pediatric DXA: clinical applications

Normal bone mineral accrual requires adequate dietary intake of calcium, vitamin D and other nutrients; hepatic and renal activation of vitamin D; normal hormone levels (thyroid, parathyroid, reproductive and growth hormones); and neuromuscular functioning with sufficient stress upon the skeleton to induce bone deposition. The presence of genetic or acquired diseases and the therapies that are used to treat them can also impact bone health. Since the introduction of clinical DXA in pediatrics in the early 1990s, there has been considerable investigation into the causes of low bone mineral density (BMD) in children. Pediatricians have also become aware of the role adequate bone mass accrual in childhood has in preventing osteoporotic fractures in late adulthood. Additionally, the availability of medications to improve BMD has increased with the development of bisphosphonates. These factors have led to the increased utilization of DXA in pediatrics. This review summarizes much of the previous research regarding BMD in children and is meant to assist radiologists and clinicians with DXA utilization and interpretation.

Bone mineral density and bone metabolism in children treated for bone sarcomas

In adolescent bone sarcoma patients, bone mass acquisition is potentially compromised at a time in which it should be at a maximum. To evaluate the problem we measured bone mineral density (BMD) and serum markers of bone formation and resorption in a series of pediatric patients with bone tumors. BMD was measured by dual-energy x-ray absorptiometry, at clinical remission, for lumbar spine and the neck of the femur in 38 osteosarcoma and 25 Ewing's sarcoma patients. Mean age was 20.65 and 19.13 y respectively. Serum markers of bone metabolism were: OC, PICP, ICTP, 25-OH vit D and 1,25-(OH)(2) vit D, IGF-I, IGFBP-3 and intact PTH. Serum was sampled throughout anti-tumoral treatments and follow-up. We analyzed 85 samples from 59 osteosarcoma patients and 54 samples from 36 Ewing's sarcoma patients. Patients had decreased lumbar and femoral BMD. The decrease was more pronounced in pubertal patients compared with those who had completed pubertal development at the time of disease diagnosis. Multivariate analysis indicated that sex, age, weight and BMI were significant in lumbar BMD depletion. Weight and BMI were significant in femoral BMD depletion. Serum markers of bone formation (PICP and OC) and resorption (ICTP) were, throughout, lower than reference values. Significant alterations in other markers were also observed. Up to a third of osteosarcoma and Ewing's sarcoma patients in clinical remission had some degree of BMD deficit. The corresponding increased risk of pathologic bone fractures constitutes a reduction in future quality of life.

Changes in bone mineral density in survivors of childhood acute lymphoblastic leukemia

BACKGROUND

There is little information about factors modulating bone mineral density (BMD) in survivors of childhood acute lymphoblastic leukemia (ALL).

PROCEDURE

We analyzed data from 57 survivors (26 male, 52 Caucasian) who underwent two serial quantitative computed tomography (QCT) studies of BMD. Using multiple linear regression, we evaluated the association of BMD change with demographic variables, treatment history, hormone therapy, exercise, and tobacco and alcohol use.

RESULTS

The median age was 3.4 years (range, 0.9-17.4 years) at diagnosis of ALL; the median age at the first QCT (Study I) was 15.0 years (range, 10.6-31.0 years) and at the second QCT (Study II) was 18.2 years (range, 14.2-35.3 years). Mean height increased 4.7 cm and mean weight increased 8.8 kg between Studies I and II. While the mean BMD increased 9.33 mg/cc (P = 0.003), the BMD Z-score increased only slightly (0.21 SD, P = 0.035). Cortical bone density increased significantly (approximately 25.3 mg/cc; P = 0.001), but the ratio of trabecular to cortical BMD decreased significantly (P = 0.045). Factors independently associated with unfavorable BMD changes included older age at diagnosis (P = 0.001), female sex (P = 0.018), and nutritional supplementation (0.032). Alcohol (P = 0.009) was an unfavorable factor in a univariable analysis.

CONCLUSIONS

Bone mineral accretion during adolescence is attenuated in childhood ALL survivors by a comparative deficit in trabecular versus cortical bone deposition. BMD is influenced favorably by exercise in early adolescence and unfavorably by the use of nutritional supplements and alcohol. These results provide new information about behavioral factors that affect bone accrual in survivors of childhood ALL and warrant definitive evaluation in a larger cohort.

No difference between prednisolone and dexamethasone treatment in bone mineral density and growth in long term survivors of childhood acute lymphoblastic leukemia

BACKGROUND

Dexamethasone is known to have both more potent leukemic activity and is associated with a higher incidence of side effects than prednisolone. In this study, we compared the long-term effects of dexamethasone and prednisolone on bone mineral density (BMD), body composition and growth in long-term survivors of ALL in first complete remission.

PROCEDURE

Ninety patients (51 male, 49 female; 8.6-38.5 year), treated with either a prednisolone containing protocol (n = 47; n = 19 also with CNS-irradiation) or a dexamethasone containing protocol (n = 43; no cranial irradiation) participated in this cross-sectional single center study. Mean follow-up was 12.7 years (2.0-29.7 years). BMD of lumbar spine and total body, and body composition were expressed as standard deviation scores (SDS) using dual energy X-ray absorptiometry. Bone mineral apparent density of the lumbar spine (BMAD) was calculated to correct for bone size.

RESULTS

There was no difference in height, height corrected for target height, BMD, or lean body mass between prednisolone and dexamethasone treated patients. Prednisolone treated patients had an increased percentage body fat (SDS +0.46; P < 0.05) and increased body mass index (SDS 0.88; P < 0.01) compared to normal. Dexamethasone treated patients had only an increased body mass index (SDS 0.52; P < 0.05). Height, total body BMD, and lean body mass were lower in patients treated with cranial irradiation as compared to non-irradiated patients, but differences in the latter two disappeared when corrected for height. BMAD was normal after CNS-irradiation.

CONCLUSIONS

Long term survivors of ALL treated with prednisolone or dexamethasone containing regimens do not differ in height, BMD, or body composition.

Evaluation of bone mineral density at different phases of therapy of childhood all

In the present study the authors evaluated the status of spinal bone mineral density (BMD) using dual-energy X-ray absorptiometry in a group of 31 children with acute lymphoblastic leukemia, treated by ALL-BFM protocols without irradiation, at different phases of their treatment. These patients were studied (1) within 2 months of diagnosis (group 1, n = 17, median time postdiagnosis 17 days), (2) during chemotherapy (group 2, n = 16, median time on treatment 22 months), and (3) shortly after completion of therapy (group 3, n = 10, median time postchemotherapy 13 months). Twelve patients underwent serial measurements in either of the groups they entered (6 patients of group 1 and 6 patients of group 2). The mean cumulative prednisone dose was 0.8, 4.3, and 5 g/m2 in groups 1, 2, and 3, respectively. A gradual decline of BMD from group 1 through group 3 was observed. The mean value of age- and sex-specific BMD z-score was -0.74 (+/-0.32) in group 1, -1.59 (+/-0.24) in group 2, and -2.03 (+/-0.27) in group 3; there was a statistically significant difference between groups 1 and 3 (p = .022). A BMD z-score < -2 was found in 3 (17%), 4 (25%), and 5 (50%) patients of groups 1, 2, and 3, respectively. In conclusion, a high incidence of reduced bone mass was observed during and shortly after treatment. These findings could have significant consequences in long-term survivors.

Bone mineral density and serum bone turnover markers in survivors of childhood acute lymphoblastic leukemia: comparison of megadose methylprednisolone and conventional-dose prednisolone treatments

During recent decades, the survival rate after childhood acute lymphoblastic leukemia (ALL) has improved substantially; consequently, the long-term side effects of ALL and its treatment have gained attention, of which osteoporosis is one of the most important. The purpose of the present study was to compare the influence of different treatment protocols that include high-dose methylprednisolone (HDMP) versus conventional-dose prednisolone (CDP) for remission-induction therapy on bone mineral density (BMD) and serum bone turnover markers in survivors of childhood ALL after cessation of chemotherapy. Thirty-six boy and 23 girl survivors, treated for ALL, were cross-sectionally studied, at a mean age of 11.7 years (range 6-19). Group 1 (n = 30) received CDP therapy (prednisolone, 2 mg/kg/day, orally) and group 2 (n = 29) received HDMP therapy (prednol-L, 900-600 mg/m2, orally). All other therapies were similar in both groups. Cranial irradiation was added for high-risk patients as soon as possible after consolidation therapy. We found that mean lumbar spine BMD z score value was -1.75 (0.83) SDS in group 1 and -1.66 (1.21) SDS in group 2. There is no difference between both groups (P = 0.736). The mean BMD z scores of prepubertal and pubertal patients were not significantly different in both groups. Comparison of serum bone turnover parameters of the patients revealed no difference between the two groups. Stepwise regression analysis revealed that lumbar spine BMD z scores was predicted by height SDS and the time past since cessation of therapy, but not age at diagnosis, BMI SDS, cranial radiotherapy, and puberty. Our study results showed that HDMP treatment did not deteriorate the bone mass any more than CDP treatment. These results proved that high-dose steroid therapy over a short period of time in remission-induction treatment would not affect the bone mass any more adversely than would conventional doses approximately 3 years after cessation of chemotherapy.

Improvement in bone mineral density and body composition in survivors of childhood acute lymphoblastic leukemia: a 1-year prospective study

OBJECTIVES

Abnormalities in bone mineral density (BMD), body composition, and bone metabolism have been reported in children who were treated for acute lymphoblastic leukemia (ALL) during and after completion of therapy. However, these studies are cross-sectional, and no longitudinal data are available in a large group of patients after completion of therapy. In the present study, 1-year longitudinal changes in BMD, body composition, and bone metabolism were evaluated in children with ALL during the first 3 years after completion of therapy without cranial irradiation.

METHODS

BMD of total body (TB; g/cm(2)), areal and apparent volumetric lumbar spine (L2-L4), lean body mass, and percentage of body fat were measured by dual-energy x-ray absorptiometry in 37 children (median age: 7.9 years; range: 4.7-20.6 years) who were treated for ALL at a median age of 3.3 years (range: 1.1-16.6 years), after a median time of 2.2 years after the completion of treatment, and after a 1-year follow-up period. Two control subjects (n = 74) who were matched for gender, age, and pubertal stage were also longitudinally investigated for body composition for 1 year. Usual serum biochemical markers of calcium metabolism and bone turnover were measured in patients during the study period.

RESULTS

A slight decrease in TB BMD was found after a median time of 2.2 years after the completion of therapy for ALL in childhood. Patients showed a significantly lower median TB BMD when evaluated <1.5 years as compared with those at >or=1.5 years since completion of therapy. At the time of first evaluation, the percentage of body fat mass was significantly higher and patients were physically less active than their matched control subjects. Although, as expected, during the 1 year of follow-up both groups showed an annual increment in their BMD measurements, a significantly higher increase in TB BMD was observed in patients in comparison with control subjects. During this same period, the increase in the percentage of body fat mass was slightly lower in ALL patients as compared with control subjects. At the end of the follow-up year, BMD, body-composition parameters, and physical activity of ALL patients were similar to those observed in matched control subjects. Serum biochemical markers of bone turnover were normal at both evaluations.

CONCLUSIONS

A significant increase in TB BMD and a tendency to a lesser increase in percentage of body fat mass were observed during the study period in ALL patients as compared with chronological age-, gender-, and pubertal stage-matched control subjects. These findings suggest a positive effect of long-term completion therapy and increase in physical activity on BMD, body composition, and bone metabolism in patients who have been treated for ALL.

A module map showing conditional activity of expression modules in cancer

DNA microarrays are widely used to study changes in gene expression in tumors, but such studies are typically system-specific and do not address the commonalities and variations between different types of tumor. Here we present an integrated analysis of 1,975 published microarrays spanning 22 tumor types. We describe expression profiles in different tumors in terms of the behavior of modules, sets of genes that act in concert to carry out a specific function. Using a simple unified analysis, we extract modules and characterize gene-expression profiles in tumors as a combination of activated and deactivated modules. Activation of some modules is specific to particular types of tumor; for example, a growth-inhibitory module is specifically repressed in acute lymphoblastic leukemias and may underlie the deregulated proliferation in these cancers. Other modules are shared across a diverse set of clinical conditions, suggestive of common tumor progression mechanisms. For example, the bone osteoblastic module spans a variety of tumor types and includes both secreted growth factors and their receptors. Our findings suggest that there is a single mechanism for both primary tumor proliferation and metastasis to bone. Our analysis presents multiple research directions for diagnostic, prognostic and therapeutic studies.

Skeletal morbidity in childhood acute lymphoblastic leukemia

PURPOSE

Treatment for acute lymphoblastic leukemia (ALL) in childhood results in a reduction in bone mineral density (BMD). Whether there is a recovery of this lost bone mass in survivors of ALL is not known. We sought to determine if changes in BMD are common long-term sequelae in children with ALL.

METHODS

Bone mineral densitometry of the lumbar spine and femoral neck was performed on 106 patients. The results were compared with those of age-matched normal controls. The effect of treatment was examined in those with low BMD compared with the remainder of the study group.

RESULTS

When data were tested with respect to age, sex, and age and sex, no difference was observed in BMD between survivors of childhood ALL and controls. In the subgroup of patients with low BMD, the difference was not related to age, age at diagnosis, or years since diagnosis. Low BMD of the spine was not explained by radiotherapy (RT), methotrexate (MTX) dose, or corticosteroid dose. Low BMD of the femur was not explained by RT. However, those with low femoral BMD were more likely to have received high-dose MTX or higher-dose corticosteroids compared with the remainder of the group.

CONCLUSION

It appears that survivors of childhood ALL as a whole recover normal BMD. However, those patients who received a total MTX dose of greater than 40000 mg/m(2) or a total corticosteroid dose of greater than 9000 mg/m(2) may not recover normal BMD and therefore should be screened for decreased BMD of the femoral neck.

Osteopenia, excess adiposity and hyperleptinaemia during 2 years of treatment for childhood acute lymphoblastic leukaemia without cranial irradiation

OBJECTIVE

Osteopenia and excess adiposity occur following treatment of childhood acute lymphoblastic leukaemia (ALL) and the use of cranial irradiation is thought to be a significant contributory factor. Hyperleptinaemia has also been demonstrated following cessation of treatment for childhood ALL. Therefore a prospective study was undertaken to evaluate serial changes in percentage bone mineral content (BMC), adiposity and serum leptin concentrations during 2 years of treatment of children with ALL with chemotherapy but without cranial irradiation.

DESIGN AND PATIENT

Only patients treated using the MRC ALL 97/ALL 97 (modified 99) protocols for childhood ALL were eligible for entry into the study. A total of 14 patients (seven male, with a median age of 7.5 years (range 3.4-16.7 years) were recruited. Serial dual energy X-ray absorptiometry (DEXA) scanning was undertaken at diagnosis and during two years of treatment. Serum leptin concentrations were determined at the same time as the scans.

RESULTS

Reductions in %BMC were observed at the hip and lumbar spine by 12 months (P < 0.01) and remained low after 24 months of treatment. Subanalysis of %BMC measurements at the hip demonstrated a greater reduction in %BMC at the trochanteric region compared to the femoral neck. The percentage corrected fat mass increased from 6 months whereas the body mass index (BMI) standard deviation score (SDS) was increased after 24 months of treatment (P < 0.05). Serum leptin concentrations increased following 24 months of therapy (P < 0.05).

CONCLUSIONS

Children treated for ALL with contemporary regimens have a predisposition to osteopenia, excess adiposity and hyperleptinaemia during treatment without cranial irradiation administration. We speculate that in addition to glucocorticoid administration, leptin resistance may account in part for these observations.

Bone density in survivors of childhood cancer

Advances in combination chemotherapy, radiation therapy, surgery, and bone marrow transplantation have resulted in markedly improved survival rates for many children with cancer. Advancements in therapy, however, have led to new concerns, namely long-term consequences of effective treatments. Young adult and adult survivors of childhood cancer are at risk for a number of disorders related to therapy. Specifically, the young adult who has survived cancer, attendant treatments, and their complications is at risk for factors that can lead to suboptimal acquisition of peak bone mass. These factors include chronic illness, nutritional deficiencies, limited physical activity, and treatment with glucocorticoids, multiagent chemotherapy, and radiation. The long-term adverse effects of these therapies on endocrine systems, especially sex steroid and growth hormone deficiencies, are additional risk factors for some patients. After a brief review of the processes associated with acquisition of peak bone mass in the young adult, this article examines the impact of cancer and cancer therapy on bone mineral density in survivors of childhood cancer.

Effects of chemotherapeutic agents on the function of primary human osteoblast-like cells derived from children

Studies in children treated with chemotherapy suggest that chemotherapeutic agents have deleterious effects on bone metabolism. We therefore evaluated the in vitro effects of clinically relevant concentrations of chemotherapeutic agents on the synthesis of type I collagen, alkaline phosphatase (AP) activity, and mineralization by primary human osteoblast-like (HOB) cells derived from children. Because serum 1,25-dihydroxyvitamin D(3) concentrations may be reduced during treatment with chemotherapy, the effect of chemotherapeutic agents on HOB cells cultured in the presence or absence of 1,25-dihydroxyvitamin D(3) was also evaluated. Type I collagen synthesis was reduced by all agents (P < 0.01) other than methotrexate, whereas the relative AP activity was increased (P < 0.01) by all agents. The relative number of cells staining intensely for AP after culture with agents increased (P < 0.05), and AP mRNA expression was increased (P < 0.01) with vincristine. 1,25-Dihydroxyvitamin D(3) ameliorated (P < 0.01) the depletion of HOB cell numbers by chemotherapeutic agents. Furthermore, vincristine and daunorubicin inhibited 1,25-dihydroxyvitamin D(3)-mediated AP activity (P < 0.01). We conclude that chemotherapeutic agents can adversely affect HOB cell function, and we speculate that this observation may account, in part, for the osteopenia observed during and after treatment of children with chemotherapy.

Assessment of bone health in children and adolescents with cancer: promises and pitfalls of current techniques

During childhood and adolescence, skeletal development is characterized by gender-, face-, and maturation-specific increases in cortical dimensions and trabecular density. Children with cancer have multiple risk factors for impuired bone mineralization, including delayed growth and maturation, sex hormone deficiencies, decreasal physical activity and biomechanical loading of the skeleton, glucocorticoid and other immunosuppressive therapies, growth hormone deficiency, and malnutrition. This review outlines the expected gains in bone dimensions, mineral content and strength during childhood and adolescence. Varied threats to bone health in the child with cancer are summarized, with special attention to potential effects on bone formation and resorption in the growing skeleton. The strengths and limitations of dual energy x-ray absorptiometry (DXA) and quantitative computed tomography (QCT) techniques in the assessment of the different disease-related effects on bone strength are discussed, and alternative analytic approaches explored.

Renal function following hematological stem cell transplantation in childhood

Renal function greatly influences mortality rates in the early phase following hematological stem cell transplantation (HSCT) in childhood, as well as the quality of life in long-term survivors. Nevertheless, the number of studies in pediatric populations is limited and some important aspects of kidney function after HSCT have only been elucidated in adults. The incidence of acute renal failure (ARF) immediately after HSCT in pediatric patients is between 25% and 50%, with 5%-10% of children requiring renal replacement therapy. Doubling of serum creatinine is associated with a twofold increase in mortality. However, the need for dialysis leads to a further increase in mortality rates to 80%-90%. Specific renal syndromes appear at different times following HSCT, revealing a similar pattern in children and adult patients. In both children and adults, impaired renal function associated with liver impairment (hepatorenal syndrome) is the most important cause for ARF. Therapeutic approaches have not been able to reduce the frequency or to improve outcome so far. In adults surviving long term, bone marrow transplant (BMT) nephropathy is the most frequent renal complication, although a considerable variation in incidence (up to 70%) has been published, partly due to various definitions and manifestations. Little is known about the long-term outcome of renal function in patients treated with HSCT in childhood. However, chronic renal failure has been reported in 0%-28%, but no end-stage renal failure has been published so far. Tubular function following HSCT is rarely investigated, although its impact on long-term survivors of BMT in childhood might be of some importance, especially for growth and bone metabolism.

Altered bone mineral density and body composition, and increased fracture risk in childhood acute lymphoblastic leukemia

OBJECTIVE

To evaluate fracture rate and bone mineral density (BMD) and body composition in children with acute lymphoblastic leukemia (ALL) treated with dexamethasone-based chemotherapy.

STUDY DESIGN

Children with ALL (n = 61) participated. At diagnosis, during therapy, and one year after cessation of therapy, BMD and body composition were measured using dual energy X-ray absorptiometry of lumbar spine (LS) and total body (TB). Serum markers of bone turnover were assessed.

RESULTS

BMD(LS) was significantly reduced at diagnosis, and remained low during therapy. BMD(TB) was normal at diagnosis, with a fast decrease in the first 32 weeks, in which chemotherapy was relatively intensive. Apparent ("volumetric") BMD(LS) was also reduced, but this did not reach significance at diagnosis and follow-up. Bone formation markers were reduced at diagnosis; formation as well as resorption markers increased during treatment. Fracture rate was 6 times higher in ALL patients compared with healthy controls. Lean body mass was decreased at baseline. Percentage of body fat increased significantly during therapy. After ALL treatment was completed, BMD and body composition tended to improve.

CONCLUSIONS

Children with ALL are at risk for osteopenia because of the disease itself and the intensive chemotherapy. Fracture rate increases substantially, not only during but also shortly after treatment.

Late endocrine, metabolic and skeletal sequelae following treatment of childhood cancer

With an ever increasing adult population of childhood cancer survivors there is a need to focus on the late effects of cancer therapy. It is essential that, after discharge from the paediatric oncologists, the patients are not lost from the health system but are under continued surveillance with access to the appropriate physicians. Endocrine and metabolic consequences may affect a patient's life both soon after cancer treatment and also for many years in the future. In this review we consider the following potential problems: growth hormone deficiency and replacement in adulthood, cardiovascular risk factors, osteopaenia, thyroid and parathyroid dysfunction.

Osteoporosis in childhood: bone density of children in health and disease

Bone mineral density in later life largely depends on the peak bone mass achieved in adolescence or young adulthood. A reduced bone density is associated with increased fracture risk in adults as well as in children. Pediatricians should therefore play an important role in the early recognition and treatment of childhood osteoporosis. Juvenile idiopathic osteoporosis and osteogenesis imperfecta are examples of primary osteoporosis in childhood. However, osteoporosis is more frequently a complication of a chronic disease or its treatment. This paper provides an overview of bone and bone metabolism in healthy children and the use of diagnostic tools, such as biochemical markers of bone turnover and several bone densitometry techniques. Furthermore, a number of diseases associated with osteoporosis in childhood and possible treatment strategies are discussed.

Bone mineral density, body composition, and height in long-term survivors of acute lymphoblastic leukemia in childhood

BACKGROUND

Childhood leukemia has increasing numbers of survivors, so more emphasis is being placed on long-term effects. The ALL-6 protocol of the Dutch Childhood Leukemia Study Group involved high-dose dexamethasone and methotrexate and no cranial irradiation. Therefore, we studied the long-term effects on bone mineral density (BMD), body composition, and growth in survivors of non-high-risk ALL treated with the ALL-6 protocol.

PROCEDURE

Twenty-three subjects (12.2-25.4 years) participated in this cross-sectional study. Mean follow-up was 9.6 years (range 7.9-11.4 years). BMD of lumbar spine (LS) and total body (TB) and body composition were measured by dual energy X-ray absorptiometry; results are expressed as standard deviation scores (SDS). Bone mineral apparent density (BMAD(LS)) was calculated to correct for bone size. A questionnaire was administered to determine physical activity, calcium intake, and medical history.

RESULTS

Mean SDS for BMD(LS), BMD(TB), and BMAD(LS) were normal. None of the subjects had BMD below -2 SDS; one subject had BMAD(LS) below -2 SDS. Mean SDS for lean body mass, percentage fat, and height were not significantly different from zero. Calcium intake correlated positively with BMD. Nine subjects reported traumatic fractures (eight during or shortly after therapy).

CONCLUSIONS

Ten years after ALL-6 treatment, no long-term side effects on height, BMD, or body composition were found in this small group of patients, despite high-dose dexamethasone and methotrexate. This study suggests that ALL treatment without cranial irradiation might not be associated with long-term side effects on growth and BMD.

The effect of chemotherapy on the growing skeleton

With the increasing use of high dose (poly)chemotherapy schedules in the treatment of childhood cancer it is particularly important to know the adverse effects of these treatments. Growth is a complex mechanism affected not only by chemotherapy but also by the malignancy itself as well as nutritional status, the use of corticosteroids and (cranial) radiation. In vitro and animal studies are often the most useful in determining the effect of a single chemotherapeutic agent on the growing skeleton. In vitro studies have shown doxorubicin, actinomycin D and cisplatin to have a direct effect on growth plate chondrocytes that in animals results in decreased growth and final height. Clinical studies with multiagent chemotherapy have demonstrated that antimetabolites decrease bone growth and final height. Childhood cancer survivors are at risk of a reduced bone mineral density, mainly due to methotrexate, ifosfamide and corticosteroids. This reduced bone mineral density persists into adult life and may increase bone fracture risk at an older age.