Reduced bone density at completion of chemotherapy for a malignancy

Load transfer across a mandible during a mastication cycle: The effects of odontogenic tumour

The extent to which load transfer in a diseased mandible with odontogenic tumour might influence the potential risk of pathological fracture has scarcely been investigated. The study sought to investigate the quantitative deviations in load transfer across healthy and cancer-affected (diseased) mandibles having odontogenic tumours. The effect of size of the tumours (small: 9 mm diameter, large: 19 mm diameter), and variation in bone mechanical (elastic) properties of the mandible on load transfer in cancer-affected mandibles during a mastication cycle have been investigated. Based on patient-specific computed tomography-scan datasets, detailed three-dimensional finite element models of healthy and diseased mandibles were developed. High stresses of 25-30 MPa and strains ∼700 µε were observed in the healthy mandible during the right molar bite. However, marginal deviations were observed in principal stress distributions in the diseased mandibles with small- and large-sized tumours, as compared to the healthy mandible. Maximum principal strains of ∼1474 µε were found in the body region adjacent to the symphysis region for small-sized tumour. Whereas for large-sized tumour, maximum strains of ∼2700 µε were observed in the right buccal regions. Reduction in Young's modulus due to different stages of odontogenic tumours had a localised effect on the principal stress distributions, but triggered an abrupt increase in the principal tensile strains. It appears that there is a potential risk of pathological fracture for large-sized odontogenic tumour, owing to high tensile stresses and strains.

Bone mineral density is compromised in very long-term survivors of irradiated childhood brain tumor

INTRODUCTION

The increase in the number of childhood brain tumor survivors warrants detailed research to increase our knowledge regarding the possible physical and psychosocial adverse outcomes of tumor and tumor therapy. The aim of this study was to evaluate the current bone health by measuring the bone mineral density (BMD) in irradiated, adult long-term survivors of childhood brain tumors.

MATERIAL AND METHODS

We studied a national cohort of 74 adult survivors of childhood brain tumors treated with irradiation in Finland between 1970 and 2008. Dual X-ray absorptiometry (DXA) was performed for the femoral necks, total hips, and lumbar spine. Laboratory tests were conducted for evaluating the pituitary, thyroid, and gonadal functions. The participants were interviewed, examined clinically, and the disease and treatment related data were retrieved from the patient files.

RESULTS

One fourth of the patients (23.6%) had sex- and age-normalized z-scores below the expected range for age (z-score ≤ -2.0). Mean BMD scores were decreased in all the DXA measurement sites. Male sex was associated with low BMD (p < .05), while body mass index (BMI) had a significant positive association with BMD (p < .01). Mode of irradiation (with or without spinal irradiation) or inclusion of chemotherapy in the treatment did not affect BMD significantly. However, patients with a ventriculoperitoneal shunt had lower BMD than those without a shunt (p < .05). Follicle stimulating hormone (FSH) and luteinizing hormone (LH) were negatively associated with BMD in women (p < .05). However, a higher cumulative dose of glucocorticoids during treatment was not associated with lower BMD, while low BMD was significantly associated with previous fractures in long bones.

DISCUSSION

Low BMD should be taken in consideration in treatment of irradiated childhood brain tumor survivors especially in those with previous fractures in long bones.

Vitamin D and Bone Minerals Status in the Long-term Survivors of Childhood Acute Lymphoblastic Leukemia

Background:

Low vitamin D and diminished bone minerals with the potential for fractures are one of the nonapparent late effects of acute lymphoblastic leukemia (ALL). Chemotherapy and radiation were known as two important risk factors. We evaluated these late effects in ALL survivors who were treated with chemotherapy or chemo plus cranial radiation therapy.

Methods:

In a case–control study, 33 of ALL survivors who were treated with chemotherapy (Group A), and 33 subjects who were treated with chemoplus cranial radiation (Group B) were compared against 33 matched age, sex, and pubertal stage of their healthy siblings (Group C). Standard anthropometric data were collected as well as Tanner staging for puberty, number of fractures since treatment, serum calcium (Ca), phosphorus (P), magnesium (Mg), alkaline phosphatase, parathyroid hormone, and 25-hydroxyvitamin D (25(OH) D). The independent t-test, one-way ANOVA, Chi-square test, and Tukey's test were used to analyze the data.

Results:

The findings indicated that the mean serum levels of 25(OH) D in ALL survivors (i.e. Groups A and B) with age mean score of 11.2 years and 12.3 years, average treatment length: 3.25 years and average time after treatment completion: 4 years, was lower compared to the controls group (12.94 ± 6.69, 14.6 ± 8.1, 20.16 ± 10.83, respectively, P < 0.001) but no significant difference was observed between Group A and B in this regard (P > 0.05). Other clinical and laboratory parameters had no significant differences between the survivors and control. Vitamin D deficiency (<20 ng/ml) was observed in 27% of group A and 24% of group B and vitamin D insufficiency (20–30 ng/ml) in 72.7% and 69.6% survivors of Group A and B and 48.5% of controls group (P = 0.003).

Conclusions:

ALL treatment is associated with the increase in prevalence of vitamin D insufficiency in the childhood ALL survivors and since the low vitamin D level potentially increases the risk of low bone density, subsequent malignancies, and cardiovascular disease in the survivors, close follow-up of such patients are highly recommended to prevent the stated complications.

Bortezomib is cytotoxic to the human growth plate and permanently impairs bone growth in young mice

Bortezomib, a novel proteasome inhibitor approved for the treatment of cancer in adults, has recently been introduced in pediatric clinical trials. Any tissue-specific side effects on bone development have to our knowledge not yet been explored. To address this, we experimentally studied the effects of bortezomib in vivo in young mice and in vitro in organ cultures of rat metatarsal bones and human growth plate cartilage, as well as in a rat chondrocytic cell line. We found that bortezomib while efficiently blocking the ubiquitin/proteasome system (UPS) caused significant growth impairment in mice, by increasing resting/stem-like chondrocyte apoptosis. Our data support a local action of bortezomib, directly targeting growth plate chondrocytes leading to decreased bone growth since no suppression of serum levels of insulin-like growth factor-I (IGF-I) was observed. A local effect of bortezomib was confirmed in cultured rat metatarsal bones where bortezomib efficiently caused growth retardation in a dose dependent and irreversible manner, an effect linked to increased chondrocyte apoptosis, mainly of resting/stem-like chondrocytes. The cytotoxicity of bortezomib was also evaluated in a unique model of cultured human growth plate cartilage, which was found to be highly sensitive to bortezomib. Mechanistic studies of apoptotic pathways indicated that bortezomib induced activation of p53 and Bax, as well as cleavage of caspases and poly-ADP-ribose polymerase (PARP) in exposed chondrocytes. Our observations, confirmed in vivo and in vitro, suggest that bone growth could potentially be suppressed in children treated with bortezomib. We therefore propose that longitudinal bone growth should be closely monitored in ongoing clinical pediatric trials of this promising anti-cancer drug.

Predictors of bone loss in childhood hematologic malignancies: a prospective study

SUMMARY

Twenty-nine children with malignancies and age, gender-matched controls were prospectively studied over 14 months. Patients had higher parathyroid hormone (PTH) levels and fat mass, lower bone mass, and bone mass increments at follow-up than controls. Lean mass, age at diagnosis, systemic and intrathecal therapy were predictors of bone mass changes on adjusted analyses.

INTRODUCTION

Children with hematologic malignances have low bone mass. We prospectively investigated anthropometric, clinical, and hormonal predictors of changes in bone mass in children receiving cancer therapy.

METHODS

Twenty-nine children, mean age of 9 ± 2.9 years and 32 age and gender-matched controls, were studied. Seven had completed their course 40 ± 22 weeks prior, while 22 were still receiving therapy for 80 ± 28 weeks. Age at diagnosis, calcium intake, exercise activity, systemic corticosteroids in dexamethasone (Dex) dose, and methotrexate (MTX), and intrathecal MTX therapy received within follow-up period were assessed. Routine chemistries, PTH, 25-hydroxy vitamin D (25-OHD), bone remodeling markers, bone mass, and body composition were measured at baseline and 14 months.

RESULTS

Patients had lower exercise activity, sun exposure, and bone markers levels than controls. They had higher PTH levels and fat mass, lower bone mass at the spine, hip, and total body, and lower increments at these sites on follow-up. Predictors of bone mass changes on univariate analyses were: age at diagnosis (R = -0.50 to -0.44, p < 0.05), Dex-MTX doses (R = -0.58 to -0.41, p < 0.05), intrathecal therapy (p < 0.03),% changes in lean mass (R = 0.37 to 0.54, p < 0.04), 25-OHD levels (R = 0.39, p < 0.03), and PTH levels (R = -0.47 to -0.41, p < 0.05). Lean mass, age at diagnosis, systemic and intrathecal therapy were predictors of bone mass changes on adjusted analyses.

CONCLUSION

This study provides insight into the pathophysiology of bone loss in children receiving cancer therapy and possible interventions to optimize their skeletal health.

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.

Avoiding the under-diagnosis of low bone mineral density in Egyptian children with chronic medical conditions affecting bone health

INTRODUCTION

The International Society for Clinical Densitometry recommended that the lumbar spine and total body less head (TBLH) are the most accurate and reproducible skeletal sites for performing areal bone mineral density (BMD) measurements. Our objective is to evaluate the role of measurement of femoral neck BMD in avoiding the under-diagnosis of low BMD being a risk for fractures in subjects with chronic medical conditions that might affect bone health.

MATERIAL AND METHODS

Subjects with chronic medical conditions that might affect bone health were studied (n = 468) and 36 healthy children were recruited as control subjects. Physical examinations, height, weight measurements and BMI were calculated. Dual-energy radiographic absorptiometry of the lumbar spine and femoral neck were measured.

RESULTS

Bone mineral density z scores in both sites were significantly reduced in chronic patients, compared with control subjects. Prevalence of very low BMD z scores (-2 or more) using lumbar DXA, femoral DXA, and either of the sites were 1.38%, 3.37%, and 3.96%, respectively, while low BMD Z scores (-1 to less than -2) were 9.52%, 18.05% and 21.14% respectively.

CONCLUSIONS

We identified a significant decrease in both lumbar and femoral BMDs in studied children. Sometimes femoral BMD is decreased while lumbar BMD is still within the normal range. For this reason we recommend that, when technically feasible and there is no facility to measure TBLH, all those patients should have lumbar spine and femoral neck bone mineral density measurements to avoid under-diagnosis of low BMD being a risk for fractures.

Early decrements in bone density after completion of neoadjuvant chemotherapy in pediatric bone sarcoma patients

Background

Bone mineral density (BMD) accrual during childhood and adolescence is important for attaining peak bone mass. BMD decrements have been reported in survivors of childhood bone sarcomas. However, little is known about the onset and development of bone loss during cancer treatment. The objective of this cross-sectional study was to evaluate BMD in newly diagnosed Ewing's and osteosarcoma patients by means of dual-energy x-ray absorptiometry (DXA) after completion of neoadjuvant chemotherapy.

Methods

DXA measurements of the lumbar spine (L2-4), both femora and calcanei were performed perioperatively in 46 children and adolescents (mean age: 14.3 years, range: 8.6-21.5 years). Mean Z-scores, areal BMD (g/cm²), calculated volumetric BMD (g/cm³) and bone mineral content (BMC, g) were determined.

Results

Lumbar spine mean Z-score was -0.14 (95% CI: -0.46 to 0.18), areal BMD was 1.016 g/cm² (95% CI: 0.950 to 1.082) and volumetric BMD was 0.330 g/cm³ (95% CI: 0.314 to 0.347) which is comparable to healthy peers. For patients with a lower extremity tumor (n = 36), the difference between the affected and non-affected femoral neck was 12.1% (95% CI: -16.3 to -7.9) in areal BMD. The reduction of BMD was more pronounced in the calcaneus with a difference between the affected and contralateral side of 21.7% (95% CI: -29.3 to -14.0) for areal BMD. Furthermore, significant correlations for femoral and calcaneal DXA measurements were found with Spearman-rho coefficients ranging from ρ = 0.55 to ρ = 0.80.

Conclusions

The tumor disease located in the lower extremity in combination with offloading recommendations induced diminished BMD values, indicating local osteopenia conditions. However, the results revealed no significant decrements of lumbar spine BMD in pediatric sarcoma patients after completion of neoadjuvant chemotherapy. Nevertheless, it has to be taken into account that bone tumor patients may experience BMD decrements or secondary osteoporosis in later life. Furthermore, the peripheral assessment of BMD in the calcaneus via DXA is a feasible approach to quantify bone loss in the lower extremity in bone sarcoma patients and may serve as an alternative procedure, when the established assessment of femoral BMD is not practicable due to endoprosthetic replacements.

Screening, prevention and management of osteoporosis and bone loss in adult and pediatric hematopoietic cell transplant recipients

Long-term survivors of hematopoietic cell transplantation (HCT) are at risk for loss of bone mineral density (BMD) and subsequent osteoporosis. There is a lack of clear guidelines for the screening, prevention and treatment of bone loss after HCT. We reviewed the prevailing literature and provide guidelines developed by our center for the screening and management of this complication. Bone loss occurs predominantly within the first 6-12 months after autologous and allogeneic HCT. Recovery first occurs in the lumbar spine and is followed by a slower recovery of BMD in the femoral neck. BMD may not return to baseline levels in patients with continuing exposure to corticosteroids and calcineurin inhibitors. All HCT recipients should be advised general interventions to reduce fracture risk including adequate intake of calcium and vitamin D. We recommend screening all adult allogeneic and autologous HCT recipients with dual-energy X-ray absorptiometry 1 year after transplantation. Patients at high risk for bone loss (for example, patients receiving ≥ 5 mg of prednisone equivalent daily for > 3 months) can be screened earlier (for example, 3-6 months after HCT). Where indicated, bisphosphonates or other anti-resorptive agents (for example, calcitonin) can be used for prevention or treatment of osteoporosis in adult HCT recipients. Pediatric HCT recipients should be referred to a pediatric endocrinologist for evaluation and treatment of bone loss. There remain several areas of uncertainty that need further research in adult and pediatric HCT recipients, such as the optimal timing and frequency of screening for loss of bone mineral density, relationship of bone loss with risk of fractures, selection of appropriate patients for pharmacologic therapy, and optimal dosing schedule and duration of therapy with anti-resorptive agents.

Assessment of bone mineral density and risk factors in children completing treatment for acute lymphoblastic leukemia

BACKGROUND

Reduced bone mineral density and increased fracture risk have been reported in children with cancer. In this study, we aimed to determine the growth and bone mineral density (BMD) of the children off chemotherapy for acute lymphoblastic leukemia, and the probable risk factors.

PROCEDURE

The age, anthropometric measurements, lumbar spine BMDs were recorded in 70 children. The risk factors on BMD; daily calcium intake, the time interval from the completion of the chemotherapy, cranial radiotherapy, cumulative steroid dose, decrease in physical activity were investigated. Serum calcium, phosphate, alkaline phosphates, magnesium, insulin-like growth factor-1 (IGF-1) and 25 (OH) vitamin D levels were determined.

RESULTS

The mean height percentile at the time of diagnosis was decreased from the value of 53 to a value of 47 at the beginning of the study (P=0.071). Of them; 44% had osteoporosis, 41% had osteopenia, and the rest had normal BMD. BMD z-scores were decreased during the first 2 years from the completion of the treatment. There was a positive correlation between BMD z-scores and daily calcium intake (CC=0.366, P=0.0015). A negative correlation was determined between the time spent on TV and computers and BMD z-scores (CC=-0.464, P=0.0019). Serum IGF-1 and 25 (OH) vitamin D levels of patients were significantly lower than controls (P=0.033).

CONCLUSIONS

Our data revealed that 85% of the survivors had bone mineralization defect. BMDs and z scores were decreased during the first 2 years from the completion of the treatment and then gradually began to increase. The most important risk factor for decreased BMD was low daily calcium intake. Therefore, patients and their families should be encouraged to take sufficient amount of calcium. Prophylactic vitamin D may also be supplemented.

Survivorship: childhood cancer survivors

Late effects of therapy for childhood cancer are frequent and serious. Fortunately, many late effects are also modifiable. Proactive and anticipatory risk-based care can reduce the frequency and severity of treatment-related morbidity. The primary care clinician should be an integral component in risk-based care of survivors. Continued communication between the "late effects" staff at the cancer center and the primary care clinician is essential for optimum care of this high-risk population.

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.

Severe osteoporosis and high level TSH in a child before the diagnosis of acute lymphoblastic leukemia

Osteoporosis in children is rare and mostly secondary to such conditions as prolonged immobilization, malabsorption syndromes, corticosteroid excess, osteogenesis imperfecta, celiac disease, Turner syndrome, and malignancy. Idiopathic juvenile osteoporosis (IJO) is a very rare condition of primary bone demineralization that presents in childhood. IJO, a disease of unknown etiology, manifests typically by pain, bone deformities, and fractures. Diagnosis of IJO was made by excluding other common causes of osteoporosis in this age. Bisphosphonates, calcitriol, fluoride, and calcitonin have been administered therapeutically, but the results were equivocal. Usually the disease remits by itself. Patient that has serious osteoporosis and high thyroid stimulating hormone level was diagnosed as IJO by eliminating secondary reasons. We report this case, whose symptoms were disappeared after parenteral pamidronat treatment, and he was reexamined owing to anemia and trombositopenia, and diagnosed as B-cell acute lymphoblastic leukemia, just to emphasis the importance of close follow-ups of IJO patients.

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.

Low bone mass in children with malignant lymphoma

The aim of this work was to study the effect of disease process on bone mass and calcium homeo-stasis in children with malignant lymphoma at diagnosis, 3 months after starting chemotherapy, and after 1 year. Evaluation of lumber vertebrae (L2-L4) bone mineral density using dual-energy X-ray absorptiometry and calcium homeostasis parameters and bone turnover biochemical markers (serum osteocalcin and urinary deoxypyridinoline) had been assayed in twenty lymphoma patients at presentation and after treatment. Low bone mass for chronological age was observed in 4 patients (20%) at diagnosis and persisted after 3 months and 1 year. Parathyroid hormone level demonstrated no differences between children with lymphoma at different stages of therapy and controls, while 25(OH) D(3) was significantly lower in lymphoma patients at different stages of therapy as compared to controls (p < .001). Osteocalcin was significantly lower in lymphoma patients at different stages of therapy. Deoxypyridinoline showed only significant higher values after 3 months of therapy compared to controls (p = .01). In conclusion, low bone mass was observed in children with lymphoma and is related to decreased osteoblastic activity and decreased mineralization of bone.

Osteopenia and cancer in children and adolescents: the fragility of success

The attainment of a satisfactory peak bone mass, which is accomplished largely by the end of adolescence, is the best protection against excessive bone mineral loss in late adulthood. Factors that influence this process include age, race, sex, body size, pubertal status, diet, physical activity, and other lifestyle elements. Cancer and its treatment in children and teenagers adversely impact bone mineralization. In particular, chemotherapy (especially glucocorticosteroids and methotrexate) and cranial irradiation (apparently by reducing growth hormone secretion and by causing hypogonadotropic hypogonadism) interfere with normal bone turnover. Resorption often exceeds formation, resulting in net bone mineral loss and providing a rational basis for the use of antiresorptive drugs. Such osteopenia may be symptomatic, with pain and abnormal gait, and increases the risk of fractures several fold. The disorder is compounded by reduced physical activity, so programs to reduce this deficit are of measurable benefit. All of those engaged in the care of children and adolescents with cancer have an opportunity to improve the bone health of these young people and to limit their risk of developing osteoporosis and fragility fractures in adult life.

QCT versus DXA in 320 survivors of childhood cancer: association of BMD with fracture history

PURPOSE

To assess agreement on diagnosis of diminished bone mineral density (BMD) and correlation between BMD values obtained by dual-energy X-ray absorptiometry (DXA) and quantitative computed tomography (QCT) in childhood cancer survivors.

PATIENTS AND METHODS

We retrospectively reviewed lumbar spine QCT and DXA studies for BMD in patients who underwent both imaging studies within a 24-hr period. We determined correlation between BMD values and agreement on diagnosis of diminished BMD obtained by both modalities. Diminished BMD was defined as two or more SDs below mean for age- and gender-matched reference values. We evaluated the relationship of BMD values determined by each modality to self-reported fracture history in the 160 (50%) patients with available reports.

RESULTS

Of 320 patients, 56% (178) were male; 87% (277) were white. Median age was 16.4 (range, 5.1-36.0) years. Median BMD Z-score was -1.43 (range, -5.96 to 3.20) by QCT and -1.30 (range, -5.50 to 2.80) by DXA. Correlation between QCT- and DXA-determined BMD values was significant but low, and agreement on diminished BMD was fair (kappa = 0.32). There was no association between BMD measured by either QCT or DXA and self-reported traumatic fracture history. Male gender was associated with doubling the traumatic fracture risk (P = 0.0499).

CONCLUSIONS

Quantitative computed tomography and DXA may give discrepant results when used to assess bone health in childhood cancer survivors, especially in those of non-white race. This inconsistency in indicators of BMD deficiency may complicate clinical decision-making. Consecutive use of a single modality is recommended to provide reliable longitudinal information.

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.

Bone mineral density decrements and children diagnosed with cancer

This integrative literature review is focused on (1) the prevalence of bone mineral density (BMD) decrements in children treated for acute lymphoblastic leukemia (ALL), and when these decrements are observed; (2) the risk factors associated with the development of decreased BMD and resultant complications in children treated for ALL; (3) the role, if any, that corticosteroids play in decreasing BMD in children treated for ALL; (4) interventions that can potentially manage bone loss in people treated for ALL during childhood or adolescence. The results showed that people who have been diagnosed with ALL can have decrements in BMD. The etiology of BMD decrements can be attributed to multiple factors including genetic endowment, lifestyle behaviors, the leukemia disease process, and treatment exposures especially to corticosteroids and cranial radiotherapy. Male gender, age greater than 10 years, and physical inactivity are associated with BMD decrements in ALL survivors. The role of pediatric oncology nurses in the management of bone disease in children with cancer across the illness trajectory is discussed.

Metabolic Bone Disease in Children

Metabolic bone disease in children includes many hereditary and acquired conditions of diverse etiology that lead to disturbed metabolism of the bone tissue. Some of these processes primarily affect bone; others are secondary to nutritional deficiencies, a variety of chronic disorders, and/or treatment with some drugs. Some of these disorders are rare, but some present public health concerns (for instance, rickets) that have been well known for many years but still persist. The most important clinical consequences of bone metabolic diseases in the pediatric population include reduced linear growth, bone deformations, and non-traumatic fractures leading to bone pain, deterioration of motor development and disability. In this article, we analyze primary and secondary osteoporosis, rickets, osteomalacia (nutritional and hereditary vitamin D-dependent, hypophosphatemic and that due to renal tubular abnormalities), renal osteodystrophy, sclerosing bony disorders, and some genetic bone diseases (hypophosphatasia, fibrous dysplasia, skeletal dysplasia, juvenile Paget disease, familial expansile osteolysis, and osteoporosis pseudoglioma syndrome). Early identification and treatment of potential risk factors is essential for skeletal health in adulthood. In most conditions it is necessary to ensure an appropriate diet, with calcium and vitamin D, and an adequate amount of physical activity as a means of prevention. In secondary bone diseases, treatment of the primary disorder is crucial. Most genetic disorders await prospective gene therapies, while bone marrow transplantation has been attempted in other disorders. At present, affected patients are treated symptomatically, frequently by interdisciplinary teams. The role of exercise and pharmacologic therapy with calcium, vitamin D, phosphate, bisphosphonates, calcitonin, sex hormones, growth hormone, and thiazides is discussed. The perspectives on future therapy with insulin-like growth factor-1, new analogs of vitamin D, strontium, osteoprotegerin, and calcimimetics are presented.

Preventing organ-specific chemotherapy toxicity

Recent advances in treatment for pediatric cancers has increased overall survival rates. As more and more survive pediatric cancer, we continue to see the emergence of late effects of treatment within pediatric and the growing adult survivor population. The evaluation of late effects was initiated approximately two decades ago, and has become an extremely important facet of pediatric oncology. This review delves into several of the most serious organ-specific late effects of pediatric cancer treatment, outline what we know and what we do not currently understand about preventing or reducing them. Clinical and bench research are necessary to develop interventions that will avoid or mitigate late effects and improve the health of pediatric cancer survivors.

Evaluation of bone metabolism in children with acute lymphoblastic leukemia after induction chemotherapy treatment

Osteopenia and osteoporosis are currently receiving particular attention as late effects of therapy in survivors of childhood acute lymphoblastic leukemia (ALL). The aim of this study was to evaluate abnormalities in bone mass and mineral homeostasis in children with ALL after induction therapy (during consolidation treatment). Lumbar spine (L2-L4) bone mineral density (BMD, g/cm(2)) was measured by dual energy X-ray absorptiometry in 20 children with ALL, a median of 25.9 months postdiagnosis and results were expressed as z-scores relative to healthy Caucasian children (controls). Serum levels of intact parathyroid hormone (iPTH), alkaline phosphatase (ALP), calcium, phosphate, and magnesium were also analyzed. In addition, the body mass indexes (kg/cm(2)) of patients and controls were calculated. Results were compared with those of 40 healthy controls. Among the 20 children with ALL (12 boys and 8 girls), 12 presented z-scores < 1 SD (normal) and 8 were osteopenic (z-score between 1 and 2.5 SD). In addition, children with ALL had reduced lumbar BMDs (z-score -0.817) in comparison to healthy controls (z-score -0.353) (p = .04). Moreover, alkaline phosphatase and intact parathyroid hormone values were significantly increased compared to controls values. The data demonstrate that bone metabolism in children with ALL during consolidation therapy is disturbed, resulting in a reduced BMD and z-score with respect to healthy controls. Since a reduced BMD predisposes to osteopenia and osteoporosis, specific attention and therapeutic interventions should be considered.

Skeletal status in survivors of acute lymphoblastic leukemia assessed by quantitative ultrasound at the hand phalanges: a longitudinal study

The skeletal growth in a course of acute lymphoblastic leukemia (ALL) may be affected, and the aim of the longitudinal study was to assess the skeletal status in survivors of (ALL). The studied population consisted of 38 subjects (17 female and 21 male) measured at the age of 13.9 +/- 3.8 years (5.7 +/- 2.9 years after completion of the therapy, 11.0 +/- 14.4 years after diagnosis) and 2 years earlier; compared with 1402 controls (628 female and 774 male). Patients and controls did not differ significantly in regard to age, height or weight. Skeletal status was assessed by quantitative ultrasound (US) measurements at the hand phalanges using the DBM Sonic 1200, which measures amplitude-dependent speed-of-sound, Ad-SoS (m/s). rms CV% was 0.43%. Mean baseline Ad-SoS value in patients was 1990 +/- 76 m/s and, at second measurement, 2045 +/- 86 m/s (p < 0.000001). In 31 patients, Ad-SoS increased and, in one patient, decreased more than the value of the least significant change. In controls, mean Ad-SoS values were 1973 +/- 64 m/s (baseline) and 2016 +/- 86 m/s (follow-up) and did not differ significantly vs. baseline values in patients. At second measurement, Ad-SoS in controls was significantly lower than in patients (p < 0.05). In five patients with low baseline Ad-SoS values, bone mineral density (BMD) at the spine using DPX-L was estimated; baseline mean BMD was 0.95 +/- 0.11 g/cm2, Z-score was 1.25 +/- 0.97 and, at second measurement, 1.16 +/- 0.07 g/cm2, Z-score was 0.23 +/- 0.43. A significant increase in BMD (p < 0.01) and Z-score (p < 0.05) was noted. In patients, Ad-SoS correlated significantly with age, period after completion of the therapy, body size and Tanner stages (r ranged from 0.43 to 0.83, p ranged from 0.0001 to 0.05). It can be concluded that skeletal status assessed by quantitative US at the hand phalanges in survivors of ALL improved significantly over the period of observation.

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.

Chemotherapy decreases epiphyseal strength and increases bone fracture risk

To establish the effect of three frequently used chemotherapeutic agents in childhood cancer on the skeleton, growing male Wistar rats were studied. Treatment with doxorubicin, methotrexate, and cisplatin reduces the proximal tibial growth plate shear strength because of a decreased surface area and maximum shear stress. After treatment the bone fracture risk of the tibia and femur is increased because of decreased bending resistance. Doxorubicin and cisplatin reduce the maximum shear stress of the proximal tibial growth plate, none of the chemotherapeutic agents inhibit bone mineralization. These effects are caused by treatment-induced malnutrition and the accompanying weight reduction and a direct effect of the chemotherapeutic agents on the skeleton. The current study confirmed the importance of preventing malnutrition during chemotherapeutic treatment in view of possible skeletal complications. During followup of children treated with chemotherapy, attention should be given to signs and symptoms suggestive of such complications.

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.

Reduced bone mineralization in adolescent survivors of malignant bone tumors: comparison of quantitative ultrasound and dual-energy x-ray absorptiometry

PURPOSE

To assess bone mineralization in adolescents with bone tumors at remission using quantitative digital ultrasound (QUS) and dual-energy x-ray absorptiometry (DEXA), and to compare the bone mineralization values obtained by both methods.

METHODS

Patients studied were 36 adolescents (21 boys, 15 girls) who had completed treatment of a bone tumor at the University Hospital of the University of Navarra (Pamplona, Spain). QUS was performed at the distal metaphysis of the proximal phalanxes of the last four fingers of the nondominant hand. A DBM Sonic 1200 Ultrasound densitometer was used. DEXA measurements were made at the lumbar spine (vertebrae L1-L4) using the Hologic QDR 4500 W device. Calcium and vitamin D daily intake and grade of physical activity were recorded.

RESULTS

Mean age at bone mineralization determination was 19.11 years. Disease-free survival was 4.97 years. Decreased bone mineralization was observed by both methods. Bone mineralization absolute values measured by QUS and DEXA were significantly correlated. The sensitivity, specificity, diagnostic accuracy, and positive and negative predictive values of QUS for predicting osteopenia were 36.4%, 80.0%, 66.7%, 44.4%, and 74.1%, respectively. Daily vitamin D intake was below the recommended dietary allowances.

CONCLUSIONS

Adolescents in remission from bone tumors have low bone mineralization determined by DEXA or QUS.

Skeletal status in survivors of childhood acute lymphoblastic leukemia assessed by quantitative ultrasound: a pilot cross-sectional study

Intensive treatment in acute lymphoblastic leukemia (ALL) with the use of multimodality therapies, including radiotherapy, corticosteroids and cytotoxic agents, may lead to disturbances in bone metabolism. The aim of this study was to determine the degree of possible changes in bone status in survivors of ALL. The studied population consisted of 54 subjects aged 13.0 +/- 3.3 years (31 girls and 23 boys). The mean age at diagnosis was 5.5 +/- 3.5 years, age at the completion of therapy was 8.4 +/- 3.5 years, and the period of follow-up was 4.6 +/- 3.4 years. Patients were divided into three subgroups (low-, moderate- and high-risk) according to the presence of risk factors of ALL and compared with 1020 healthy subjects (508 girls and 512 boys). Patients and controls did not differ significantly in regard to age, height, or weight. Bone status was assessed by quantitative ultrasound (US) at right (dominant) hand phalanges using DBM Sonic 1200 (IGEA, Carpi, Italy) that measures amplitude-dependent speed of sound (Ad-SoS, m/s). Root mean square (RMS)_CV% was 0.43%. Mean Ad-SoS values were 2018 +/- 73 m/s in patients and 2003 +/- 80 m/s in controls and did not differ significantly. Ad-SoS tended to be lower in moderate- and high-risk patients, but differences were not significant. Ad-SoS correlated significantly with age in patients (r value ranged from 0.63 to 0.77, p < 0.01) and controls (r value ranged from 0.79 to 0.84, p < 0.0001). In multiple forward regression analysis, the following equation was obtained: Ad-SoS (m/s) = 1878 (m/s) + 11.4 x age at the study (y) + 4.0 x period after therapy completion (y) - 9.5 x duration of the therapy (y). It can be concluded that bone status assessed by quantitative US at the hand phalanges in survivors of acute lymphoblastic leukemia 4.6 years after completion of the therapy is not affected in comparison to healthy controls.

Male sex and low physical activity are associated with reduced spine bone mineral density in survivors of childhood acute lymphoblastic leukemia

Survivors of acute lymphoblastic leukemia (ALL) are at risk of osteoporosis and obesity. We studied bone mineral density (BMD), percent of fat mass (%FM), and activity levels in survivors of ALL treated without radiotherapy. Lumbar and total areal BMD (g/cm2) and %FM were measured in 28 survivors (aged 5.7-14.7 years) of childhood ALL by dual-energy X-ray absorptiometry (DXA) scan (GE Lunar, Prodigy) an average of 5 years after completion of chemotherapy (UK Medical Research Council randomized trial protocol XI [UKALL XI]). One boy fractured his arm during treatment. Apparent volumetric lumbar BMD (BMD(vol); g/cm3) was calculated and %FM was adjusted for sex and age (%FM(adj)). Physical activity was measured by accelerometer and questionnaire. The results were compared with 28 sex- and age-matched healthy controls. Total body and lumbar areal BMD (g/cm2) were not different between the ALL group and the control group. However, mean lumbar BMD(vol) in survivors of ALL was significantly lower than in controls (0.303 +/- 0.036 g/cm3 vs. 0.323 +/- 0.03 g/cm3; p < 0.01), which mostly was caused by the difference in boys (0.287 +/- 0.032 g/cm3 vs. 0.312 +/- 0.027 g/cm3; p < 0.05). Weekly activity score by questionnaire was significantly lower in the ALL group than in the control group (geometric mean 50 vs. geometric mean 74; p < 0.05). Male gender, low activity levels and an intravenous (iv) high dose of methotrexate were associated with low lumbar BMD(vol). Patients who received an iv high dose of methotrexate (n = 18) had significantly higher %FM(adj) than those with intrathecal methotrexate only (n = 10; 141 +/- 70% vs. 98 +/- 37%;p < 0.05). In conclusion, male survivors of childhood ALL have reduced lumbar BMD(vol), whereas no such difference was seen in girls. Overall, survivors of ALL were physically less active than their healthy controls and lower activity correlated with lower lumbar BMD(vol) and higher %FM(adj).

Loss of bone mass and vitamin D deficiency after hematopoietic stem cell transplantation: standard prophylactic measures fail to prevent osteoporosis

Bone mineral density (BMD) and biochemical markers of bone metabolism were analyzed in 67 adults with ALL (n = 27), AML (n = 14), MDS (n = 6) and CML (n = 20) before and after allogeneic stem cell transplantation (SCT). Median age was 36 years (17-56). Twenty-six out of 53 patients (49%) had osteopenia and osteoporosis before SCT, 21/26 had acute leukemias and 5/26 had chronic myeloid leukemia (CML). T-score before SCTwas -1.23 in patients with acute leukemias and 0.62 in CML patients (P = 0.001). After SCT, a significant loss of BMD was observed in all patients. After 6 months, 24 of 36 evaluable patients (67%) had pathologic BMD, 11 of them (30%) had developed osteoporosis. After 12 months, 20 of 32 evaluable patients (62%) had BMD values below normal and nine of them (28%) had osteoporosis. Increased pyridinium excretion was observed in 12/20 patients (60%) with acute leukemias, but only in 3/13 (23%) with CML (P = 0.014). A prolonged vitamin D deficiency for more than 6 months developed early after SCT in all patients. Patients with acute leukemias frequently have osteopenia and osteoporosis before SCT. After SCT, a further loss of BMD occurs independent from the underlying disease. Standard prophylactic measures are not sufficient to prevent loss of bone mass. Studies on prophylactic interventions are needed to prevent severe osteoporosis in long-term survivors of SCT.

Osteoporosis in survivors of acute lymphoblastic leukemia

Osteoporosis is currently receiving increasing attention as an important late effect in survivors of childhood cancer and its treatment because of their quality of life and its negative effect on the survivors' ability to perform developmentally appropriate activities. Survivors of childhood cancer are especially vulnerable because they are affected during childhood and adolescence, a time when peak bone mass should be achieved. This paper reviews decreased bone density in acute lymphoblastic leukemia (ALL), which is the most common childhood cancer and has a cure rate approaching 80%. Osteopenia/osteoporosis has been observed in all phases of the disease: at diagnosis, during treatment, and throughout the post-treatment period for as long as 20 years. Among the findings that have been described are musculoskeletal pain, disturbed gait, fractures, kyphosis, lordosis, and growth failure. Risk factors not specifically related to ALL include smoking, ingestion of carbonated beverages, and family history of "brittle bone" or fractures. Patients should be counseled in regard to diet, exercise, smoking cessation, and avoidance of carbonated beverages. There are a number of options for specific drug therapy; however, the administration of bisphosponates to children and adolescents must be approached with caution. Research is needed to determine how extensive the problem is and how to best prevent and treat the osteopenia/osteoporosis associated with ALL.

Bony morbidity in children treated for acute lymphoblastic leukemia

PURPOSE

Corticosteroids are widely used in the treatment of acute lymphoblastic leukemia (ALL). To determine the frequency of corticosteroid-associated bony morbidity in children with ALL, we retrospectively evaluated the incidence of fractures and osteonecrosis (ON) on two consecutive pediatric ALL protocols.

PATIENTS AND METHODS

One hundred seventy-six consecutive children were treated for ALL between 1987 and 1995 at the Dana-Farber Cancer Institute and Children's Hospital. Prednisone was used as the corticosteroid during postremission therapy from 1987 to 1991, and dexamethasone was used from 1991 to 1995. Medical records for all patients were reviewed to assess the occurrence of fractures and ON.

RESULTS

With a median follow-up of 7.6 years, the 5-year cumulative incidence (CI) +/- SE of any bony morbidity for the 176 patients was 30% +/- 4%, with a 5-year CI of fractures of 28% +/- 3% and of ON of 7% +/- 2%. With multivariate analysis, independent predictors of bony morbidity included age 9 to 18 years at diagnosis (P <.01), male sex (P <.01), and treatment with dexamethasone (P =.01). Dexamethasone was associated with a higher risk of fractures (5-year CI, 36% +/- 5% v 20% +/- 4% with prednisone; P =.04), but not ON (P =.40). The 5-year event-free survival for the 176 patients was 79% +/- 3%.

CONCLUSION

Children treated for ALL had a high incidence of fractures and ON. Older children, boys, and patients receiving dexamethasone were at increased risk for the development of bony morbidity. Future studies should attempt to minimize corticosteroid-associated bony morbidity without compromising clinical efficacy.

Normal bone mineral density after treatment for childhood acute lymphoblastic leukemia diagnosed between 1991 and 1998

OBJECTIVE

We investigated whether previous reports of reduced bone mineral density after management for childhood acute lymphoblastic leukemia (chALL) were confirmed in a more recently treated cohort.

STUDY DESIGN

In a cross-sectional study 75 subjects who were given the diagnosis of chALL between January 1, 1991, and December 31, 1997 (69% standard, 31% high risk), at Denver Children's Hospital and who were 11 to 82 months post-diagnosis with no history of relapse, secondary malignancy, or transplant underwent whole body areal bone mineral densitometry (BMD(A) expressed as age- and sex-standardized z scores), a food frequency questionnaire, and a weight-bearing activity survey.

RESULTS

Overall, the mean whole body BMD(A) z score was normal (+0.22 +/- 0.96). A significant positive association was found with whole body BMD(A) z score and years elapsed since the beginning of maintenance (linear regression coefficient = +0.2 Deltaz score/year; 95% CI = 0.09 to 0.3) after adjustment was done for risk status/age category, history of cranial radiation, and total days hospitalized. No association was found with high risk/older age at diagnosis, nutrient intake, chemotherapy dosage, or weight-bearing activity.

CONCLUSION

Contrary to previous reports in which cranial radiation and longer hospitalizations were prominent components of therapy, our study suggests that more recently treated patients with chALL do not have persistent abnormalities of bone mineral density after completion of therapy.

Renal function in long-term survivors of stem cell transplantation in childhood. A prospective trial

The aim of this prospective study was to assess glomerular and tubular renal function before, and 1 and 2 years after hematological stem cell therapy (HSCT) in children and adolescents. 137 consecutive patients undergoing HSCT, for malignant diseases, were included in a prospective trial. Forty-four patients were followed for up to 1 year after HSCT and 36 for up to 2 years, without relapse. Ninety healthy school children were used as a control group. The following parameters were investigated: inulin clearance (GFR), urinary excretion of albumin, alpha1-microglobulin (alpha1-MG), calcium, beta-N-acetylglucosaminidase (beta-NAG) and Tamm-Horsfall protein (THP), tubular phosphate reabsorption (TP/Cl(cr)) and percent reabsorption of amino acids (TAA). Significantly lower GFR was found 1 and 2 years after HSCT but within the normal range in the period before HSCT. There was no correlation between GFR within the first month after HSCT and long-term outcome of GFR. Tubular dysfunction was found in 14-45% of patients 1 and 2 years after HSCT depending on the parameter investigated. Pathological values 1 and 2 years after HSCT were found for alpha1-MG excretion in 40% and 39%, respectively, for TP/Cl(cr) in 44% and 45%, for beta-NAG in 26% and 19%. Median TP/Cl(cr) was significantly lower 2 years after HSCT than before. TAA was mildly impaired in 7/14 patients before, in 5/29 one and in 9/29 2 years after HSCT, but median TAA was within normal range at all times. The median excretion of albumin, THP and calcium was within the normal range at all investigations. No influence of ifosfamide pre-treatment on the severity of tubulopathy was found. The investigation of tubular renal function should be part of a long-term follow-up in children after HSCT.

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.

Impaired development of bone mineral density during chemotherapy: a prospective analysis of 46 children newly diagnosed with cancer

Osteopenia and osteoporosis are becoming increasingly recognized in children with cancer, though reasons for these changes are poorly understood. The purpose of the present study was to evaluate longitudinal changes in bone mineral density (BMD) and bone turnover in newly diagnosed children with a malignancy. Lumbar spine (L2-L4) and femoral neck bone mineral density (BMDareal, g/cm2) was measured by dual-energy X-ray absorptiometry in 46 children (age 2.9-16.0, median 8.0 years; 15 leukemias, 12 lymphomas, 19 solid tumors) at diagnosis, and after 6 months from the baseline. The apparent volumetric bone mineral density (BMDvol) was calculated to minimize the effect of bone size on BMD. Serum levels of osteocalcin (OC), type I collagen carboxy-terminal propeptide (PICP), and type I collagen carboxy-terminal telopeptide (ICTP) were analyzed at diagnosis, and during a 6-month follow-up. A significant decrease in lumbar BMDvol (-2.1%, p < 0.05), and in femoral BMDareal (-9.9%, p = 0.0001) and BMDvol (-8.5%, p = 0.0001) was observed after 6 months when compared with baseline measurements. The markers of bone formation (PICP, OC) were significantly decreased, and the marker of bone resorption (ICTP) was significantly increased at diagnosis as compared with normal values. By the end the follow-up, the levels of PICP and OC were normalized, whereas the level of ICTP continued to increase indicating that there was a negative balance in bone turnover. A deficient accumulation of bone mass might predispose children with a malignancy to impaired development of peak bone mass. A controlled study determining the benefits of an early intervention on bone turnover should be considered in these patients.

Disturbance in bone turnover in children with a malignancy at completion of chemotherapy

BACKGROUND

Osteoporosis and pathological fractures have been observed in children with a malignancy. The mechanisms of osteopenia in childhood malignancies have not been well established. The purpose of the present study was to evaluate changes in bone turnover and in bone hormonal metabolism in children with a malignancy at completion of their chemotherapy.

PROCEDURE

Serum levels of human intact osteocalcin, type I collagen carboxyterminal propeptide (PICP), type I collagen carboxyterminal telopeptide (ICTP), 25-hydroxyvitamin D [25-(OH)-D], 1,25-dihydroxyvitamin D [1, 25-(OH)(2)-D], intact parathyroid hormone, insulin-like growth factor I (IGF-I), IGF binding protein 3 (IGFBP-3), alkaline phosphatase, calcium, and phosphate were analyzed in 22 children with acute lymphoblastic leukemia and in 26 children with other malignancies. Results were expressed as Z-scores [mean (95% confidence intervals)] relative to healthy Caucasian-children.

RESULTS

The marker of collagen degradation (ICTP) was significantly increased [1.43 (1.10-1.76), P < 0.0001] compared to reference values, whereas the markers of bone formation (PICP, osteocalcin) were not changed [0.07 (-0.55 to 0.49), 0.35 (-0.05 to 0.74), respectively, NS]. Serum 25-(OH)-D, 1,25-(OH)(2)-D, and calcium were significantly reduced [-0.65 (-0.87 to -0.42), -0.68 (-0.92 to -0. 42), -1.42 (-1.80 to -1.04), P < 0.0001, respectively].

CONCLUSIONS

Disturbance in bone turnover with low serum 25-(OH)-D, 1, 25-(OH)(2)-D, and calcium was observed in children with a malignancy at completion of their chemotherapy. A controlled study determining the possible benefits of vitamin D and calcium supplementation on bone turnover could be considered in these patients.