Osteoporosis in survivors of acute lymphoblastic leukemia

Aging and Bone Metabolism

Changes in bone architecture and metabolism with aging increase the likelihood of osteoporosis and fracture. Age-onset osteoporosis is multifactorial, with contributory extrinsic and intrinsic factors including certain medical problems, specific prescription drugs, estrogen loss, secondary hyperparathyroidism, microenvironmental and cellular alterations in bone tissue, and mechanical unloading or immobilization. At the histological level, there are changes in trabecular and cortical bone as well as marrow cellularity, lineage switching of mesenchymal stem cells to an adipogenic fate, inadequate transduction of signals during skeletal loading, and predisposition toward senescent cell accumulation with production of a senescence-associated secretory phenotype. Cumulatively, these changes result in bone remodeling abnormalities that over time cause net bone loss typically seen in older adults. Age-related osteoporosis is a geriatric syndrome due to the multiple etiologies that converge upon the skeleton to produce the ultimate phenotypic changes that manifest as bone fragility. Bone tissue is dynamic but with tendencies toward poor osteoblastic bone formation and relative osteoclastic bone resorption with aging. Interactions with other aging physiologic systems, such as muscle, may also confer detrimental effects on the aging skeleton. Conversely, individuals who maintain their BMD experience a lower risk of fractures, disability, and mortality, suggesting that this phenotype may be a marker of successful aging. © 2023 American Physiological Society. Compr Physiol 13:4355-4386, 2023.

Methotrexate treatment suppresses osteoblastic differentiation by inducing Notch2 signaling and blockade of Notch2 rescues osteogenesis by preserving Wnt/β-catenin signaling

Methotrexate (MTX) is a commonly used antimetabolite in cancer treatment. Its intensive use is linked with skeletal adverse effects such as reduced bone formation and bone loss, and yet little information is available on molecular mechanisms underlying MTX-induced impaired bone formation. This study investigated the effects of MTX treatment at a clinical chemotherapy relevant dose on osteogenic differentiation in MC3T3E1 osteoblastic cells. To investigate the potential mechanisms, the expression of 87 genes regulating osteoblast differentiation and bone homeostasis was screened in MTX-treated versus untreated cells by polymerase chain reaction (PCR) arrays and results illustrated significant upregulation of Notch2 and Notch target genes at both early and late stages of MC3T3E1 differentiation following MTX treatment. To confirm the roles of Notch2 pathway and its potential action mechanisms, MC3T3E1 cells were treated with MTX with an anti-Notch2 neutralizing antibody or control IgG and effects were examined on osteogenesis and activation of the Wnt/β-catenin pathway. Our results demonstrated that induction of Notch2 activity is associated with MTX adverse effects on osteogenic differentiation and blocking Notch2 rescues osteoblast differentiation by preserving activation of the Wnt/β-catenin pathway.

Broad application prospects of bone turnover markers in pediatrics

BACKGROUND

Bone turnover markers (BTMs) have been studied for application in clinical medicine. However, BTMs in children are challenging, and few studies explore these BTMs in children. The application of BTMs is complicated mainly due to pre-analytical factors, variable reference intervals of age- and sex-related BTMs for adolescents and children in different regions and laboratories. Therefore, laboratory testing of BTMs is critical for understanding pediatric bone development and metabolism, which provides additional information about bone development and diseases.

METHODS

Literature search was conducted using the MeSH term "child" combined with the terms that bone turnover markers such as "osteocalcin," "Procollagen type I N-terminal propeptide," "procollagen type I C-terminal propeptide," "osteocalcin," "N-terminal cross-linked telopeptide," and "C-terminal cross-linked telopeptide," Several databases including Web of Science, Google Scholar, and PubMed were searched to obtain the relevant studies.

RESULTS

BTMs represent the combined effects of skeletal development, growth, and remodeling in children, which can be used in clinical pediatrics to assist in the diagnosis and prognosis of bone metabolic disorders.

CONCLUSION

BTMs are clearly helpful for diagnosis and monitoring of bone growth and development as well as bone metabolic disorders.

Therapeutic Targeting Notch2 Protects Bone Micro-Vasculatures from Methotrexate Chemotherapy-Induced Adverse Effects in Rats

Intensive cancer chemotherapy is well known to cause bone vasculature disfunction and damage, but the mechanism is poorly understood and there is a lack of treatment. Using a rat model of methotrexate (MTX) chemotherapy (five once-daily dosses at 0.75 mg/kg), this study investigated the roles of the Notch2 signalling pathway in MTX chemotherapy-induced bone micro-vasculature impairment. Gene expression, histological and micro-computed tomography (micro-CT) analyses revealed that MTX-induced micro-vasculature dilation and regression is associated with the induction of Notch2 activity in endothelial cells and increased production of inflammatory cytokine tumour necrosis factor alpha (TNFα) from osteoblasts (bone forming cells) and bone marrow cells. Blockade of Notch2 by a neutralising antibody ameliorated MTX adverse effects on bone micro-vasculature, both directly by supressing Notch2 signalling in endothelial cells and indirectly via reducing TNFα production. Furthermore, in vitro studies using rat bone marrow-derived endothelial cell revealed that MTX treatment induces Notch2/Hey1 pathway and negatively affects their ability in migration and tube formation, and Notch2 blockade can partially protect endothelial cell functions from MTX damage.

Notch2 Blockade Mitigates Methotrexate Chemotherapy-Induced Bone Loss and Marrow Adiposity

Childhood cancer methotrexate (MTX) chemotherapy often causes bone growth impairments, bone loss, and increased risks of fractures during or after treatment, for which the pathobiology is unclear and there is a lack of specific treatment. Our time course analyses of long bones from rats receiving intensive MTX treatment (mimicking a clinical protocol) found decreased trabecular bone volume, increased osteoclast formation and activity, increased adipogenesis in the expense of osteogenesis from the bone marrow stromal cells at days 6 and 9 following the first of five daily MTX doses. For exploring potential mechanisms, PCR array expression of 91 key factors regulating bone homeostasis was screened with the bone samples, which revealed MTX treatment-induced upregulation of Notch receptor NOTCH2, activation of which is known to be critical in skeletal development and bone homeostasis. Consistently, increased Notch2 activation in bones of MTX-treated rats was confirmed, accompanied by increased expression of Notch2 intracellular domain protein and Notch target genes HEY1, HES1 and HEYL. To confirm the roles of Notch2 signalling, a neutralising anti-Notch2 antibody or a control IgG was administered to rats during MTX treatment. Microcomputed tomography analyses demonstrated that trabecular bone volume was preserved by MTX+anti-Notch2 antibody treatment. Anti-Notch2 antibody treatment ameliorated MTX treatment-induced increases in osteoclast density and NFATc1 and RANKL expression, and attenuated MTX-induced bone marrow adiposity via regulating Wnt/β-catenin signalling and PPARγ expression. Thus, Notch2 signalling plays an important role in mediating MTX treatment-induced bone loss and bone marrow adiposity, and targeting Notch2 could be a potential therapeutic option.

Alterations in Bone Turnover during Chemotherapy in Children with Acute Lymphoblastic Leukemia

Background Disturbances of bone metabolism frequently occur in children with acute lymphoblastic leukemia (ALL), leading to increased risk of osteopenia and osteoporosis at diagnosis, during and after completion of chemotherapy. The present study was performed to evaluate alteration in bone mineral metabolism in children with ALL during chemotherapy.

Method Fifty newly diagnosed patients with ALL in the age group of 2 to 14 years were included. Relapsed and refractory cases were excluded. Enrolled children were stratified into standard and high risk according to National Cancer Institute criteria. Quantitative analysis of bone resorptive marker carboxyl-terminal telopeptide of human type 1 collagen (ICTP) was assessed at baseline and 3 months after chemotherapy by the sandwich enzyme-linked immunosorbent assay technique.

Results Of 50 patients enrolled, 21 were standard and 29 were high risk. The mean age was 7.75 ± 4.0 years and the male-to-female ratio was 3.5:1. ICTP levels were analyzed in 44 patients, of which 37 (84%) showed significantly increased levels. The mean ICTP level in patients at diagnosis and controls was 1.78 ± 1.39 and 0.96 ± 0.32 µg/L, respectively ( p = 0.001). The mean ICTP level at 3 months after chemotherapy increased to 3.55 ± 1.40 µg/L ( p = 0.000). It was significantly increased in males ( p = 0.000) and in B cell ALL group ( p = 0.000) in comparison to females and T cell group. Both standard and high risk groups were equally affected ( p = 0.000). On multivariate analysis, no single risk factor could be identified.

Conclusion The marker of bone resorption (ICTP) in children with ALL was increased at diagnosis, which further increased during chemotherapy. The disease itself and the intensive chemotherapy both contributed to the increased levels.

Aqua-Plyometric Exercises: Potential Implications for Bone Mineral Density, Functional Capacity, and Quality of Life in Survivors of Childhood Acute Lymphoblastic Leukemia

OBJECTIVE

This study endeavored to explore the effect of an aquatic-based plyometric exercise program (Aqua-PLYO) on bone mineralization, functional capacity, and quality of life in survivors of childhood acute lymphoblastic leukemia (ALL).

DATA SOURCES

In a prospective, single-blinded quasi-experimental study, 30 survivors of childhood ALL (63.3% boys; age: 13.1 ± 2.8 years) were allocated to undergo the Aqua-PLYO exercise program (Aqua-PLYO group; n = 15) or the usual physical therapy (Control group; n = 15). Bone mineralization (bone mineral density [BMD], bone mineral content [BMC], BMD Z-score, and BMD volumetric [BMD_vol]), functional capacity, and quality of life were assessed prior to, and following 36 treatment sessions, which were undertaken over nonconsecutive days in a 12-week program. With controlling for the pretreatment values, all measures of bone mineralization, functional capacity, and quality of life showed more favorable posttreatment improvement in the Aqua-PLYO group as compared to the control group (all P < .05).

CONCLUSION

The Aqua-PLYO exercises, besides the usual physical therapy, can effectively improve bone health, increase functional capacity, and promote a better quality of life in long-term survivors of childhood ALL.

IMPLICATIONS FOR NURSING PRACTICE

Although survivors of childhood ALL experience reduced BMD, functional ability, and quality of life, Aqua-PLYO exercises can have positive effects on survivors' physical and functional disturbances and can, even more, be enjoyable and increase their motivation and interest in engaging in exercise interventions.

Bone Mineral Metabolism During Chemotherapy in Childhood Acute Lymphoblastic Leukemia

OBJECTIVE

The aim of this study was to evaluate levels of vitamin D, bone mineral density (BMD), and radiograph features at diagnosis and after 6 months of chemotherapy in patients with acute lymphoblastic leukemia (ALL). Vitamin D levels were also correlated with BMD and radiograph features.

MATERIALS AND METHODS

25-Hydroxy vitamin D [25(OH)D] levels, BMD, and radiograph features were assessed in 50 newly diagnosed patients of ALL in the age group of 2 to 14 years. A total of 30 age-matched and sex-matched children were recruited as controls. Vitamin D deficiency was defined as 25(OH)D <10 ng/mL, Vitamin D insufficiency as 10 to 29 ng/mL, and Vitamin D sufficiency as ≥30 ng/mL. Enzyme immunoassay (EIA) was used for the quantitative measurement of 25(OH)D levels in plasma and a LUNAR DPX NT bone densitometer was used for the assessment of BMD.

RESULTS

The mean age of the patients was 6.3 years, with a male:female ratio of 1.38:1. The mean 25(OH)D levels were 31.90±16.90 ng/mL in patients at diagnosis against 41.63±20.50 ng/mL in controls (P=0.02). Levels were 18.50±11.10 ng/mL postchemotherapy (P=0.00). Female sex was a risk factor for deficient 25(OH)D levels. There was a significant decrease in BMD postchemotherapy in the age groups of 5 to 10 and above 10 years at the femoral neck. Osteopenic changes were observed in more number of patients after 6 months of chemotherapy. There was a significant correlation between vitamin D levels, BMD, and osteopenic changes.

CONCLUSIONS

Vitamin D deficiency was common among ALL patients, which worsened after chemotherapy. This had a significant correlation with BMD and osteopenic changes in radiograph.

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.

Roles of apoptotic chondrocyte-derived CXCL12 in the enhanced chondroclast recruitment following methotrexate and/or dexamethasone treatment

Intensive use of methotrexate (MTX) and/or dexamethasone (DEX) for treating childhood malignancies is known to cause chondrocyte apoptosis and growth plate dysfunction leading to bone growth impairments. However, mechanisms remain vague and it is unclear whether MTX and DEX combination treatment could have additive effects in the growth plate defects. In this study, significant cell apoptosis was induced in mature ATDC5 chondrocytes after treatment for 48 h with 10^-5  M MTX and/or 10^-6  M DEX treatment. PCR array assays with treated cells plus messenger RNA and protein expression confirmation analyses identified chemokine CXCL12 having the most prominent induction in each treatment group. Conditioned medium from treated chondrocytes stimulated migration of RAW264.7 osteoclast precursor cells and formation of osteoclasts, and these stimulating effects were inhibited by the neutralizing antibody for CXCL12. Additionally, while MTX and DEX combination treatment showed some additive effects on apoptosis induction, it did not have additive or counteractive effects on CXCL12 expression and its functions in enhancing osteoclastic recruitment and formation. In young rats treated acutely with MTX, there was increased expression of CXCL12 in the tibial growth plate, and more resorbing chondroclasts were found present at the border between the hypertrophic growth plate and metaphysis bone. Thus, the present study showed an association between induced chondrocyte apoptosis and stimulated osteoclastic migration and formation following MTX and/or DEX treatment, which could be potentially or at least partially linked molecularly by CXCL12 induction. This finding may contribute to an enhanced mechanistic understanding of bone growth impairments following MTX and/or DEX therapy.

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

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

Nutritional Status of Pediatric Cancer Patients at Diagnosis and Correlations with Treatment, Clinical Outcome and the Long-Term Growth and Health of Survivors

Malnutrition is caused either by cancer itself or by its treatment, and affects the clinical outcome, the quality of life (QOL), and the overall survival (OS) of the patient. However, malnutrition in children with cancer should not be accepted or tolerated as an inevitable procedure at any stage of the disease. A review of the international literature from 2014 to 2019 was performed. Despite the difficulty of accurately assessing the prevalence of malnutrition, poor nutritional status has adverse effects from diagnosis to subsequent survival. Nutritional status (NS) at diagnosis relates to undernutrition, while correlations with clinical outcome are still unclear. Malnutrition adversely affects health-related quality of life (HRQOL) in children with cancer and collective evidence constantly shows poor nutritional quality in childhood cancer survivors (CCSs). Nutritional assessment and early intervention in pediatric cancer patients could minimize the side effects of treatment, improve their survival, and reduce the risk of nutritional morbidity with a positive impact on QOL, in view of the potentially manageable nature of this risk factor.

β-Catenin signaling is important for osteogenesis and hematopoiesis recovery following methotrexate chemotherapy in rats

Cancer chemotherapy can significantly impair the bone formation and cause myelosuppression; however, their recovery potentials and mechanisms remain unclear. This study investigated the roles of the β-catenin signaling pathway in bone and bone marrow recovery potentials in rats treated with antimetabolite methotrexate (MTX) (five once-daily injections, 0.75 mg/kg) with/without β-catenin inhibitor indocyanine green (ICG)-001 (oral, 200 mg/kg/day). ICG alone reduced trabecular bone volume and bone marrow cellularity. In MTX-treated rats, ICG suppressed bone volume recovery on Day 11 after the first MTX injection. ICG exacerbated MTX-induced decreases on Day 9 osteoblast numbers on bone surfaces, their formation in vitro from bone marrow stromal cells (osteogenic differentiation/mineralization), as well as expression of osteogenesis-related markers Runx2, Osx, and OCN in bone, and it suppressed their subsequent recoveries on Day 11. On the other hand, ICG did not affect MTX-induced increased osteoclast density and the level of the osteoclastogenic signal (RANKL/OPG expression ratio) in bone, suggesting that ICG inhibition of β-catenin does nothing to abate the increased bone resorption induced by MTX. ICG also attenuated bone marrow cellularity recovery on Day 11, which was associated with the suppressed recovery of CD34⁺ or c-Kit⁺  hematopoietic progenitor cell contents. Thus, β-catenin signaling is important for osteogenesis and hematopoiesis recoveries following MTX chemotherapy.

Thromboembolism prophylaxis during L-asparaginase therapy in acute lymphoblastic leukemia - time to reconsider current approaches?

Acute Lymphoblastic Leukemia (ALL) is the commonest malignancy in childhood with a second incidence peak in adulthood. Improvements in pediatric therapy including the addition of L-asparaginase (L-ASP) have enabled cure rates in excess of 90% to be achieved in children. More recently L-ASP-containing pediatric protocols are being used to treat younger adults with ALL and have improved survival by approximately 2-fold. However, a toxicity associated with L-ASP-containing therapy in ALL is venous thromboembolism (VTE) which is associated with significant morbidity in this patient population and results in interruptions in L-ASP therapy that can impact on survival outcomes. The incidence of VTE among adult patients with ALL receiving L-ASP containing therapy has been reported to be as high as 43%. Despite this, there is a lack of evidence-based recommendations for VTE prophylaxis in this clinical context; low-molecular weight heparin (LMWH) and/or AT replacement have mostly been used. The low-quality data and inconveniences associated with these VTE prophylaxis regimens highlight the need to evaluate alternatives such as direct oral anticoagulants for the prevention of L-ASP-associated VTE in ALL. This narrative will review the body of evidence on primary thromboprophylaxis in adult patients with ALL receiving L-ASP containing therapy.

Effects of chemotherapy agents used to treat pediatric acute lymphoblastic leukemia patients on bone parameters and longitudinal growth of juvenile mice

Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. Therapies for pediatric ALL have improved such that more than 80% of patients survive to 5 years post-therapy, and most survive to adulthood. These ALL patients experience long-term side effects that permanently affect their quality of life, with bone loss and reduced longitudinal growth being the most common skeletal complications. To determine the effects of the chemotherapeutic agents used in ALL induction therapy on bone density and longitudinal growth in mice, we treated juvenile mice with doxorubicin, dexamethasone, vincristine, l-asparaginase, or combination therapy. At adulthood, mice were culled and bones collected and scanned by micro-computed tomography (micro-CT). Mice that received doxorubicin and combination therapy exhibited reduced longitudinal growth and significant reductions in trabecular bone volume, trabecular thickness, and trabecular number, with increased trabecular separation. Mean cortical thickness, cortical area, marrow area, endocortical perimeter, and polar moment of inertia were significantly reduced by doxorubicin and combination therapy. Vincristine treatment significantly decreased trabecular bone volume, trabecular number, and increased trabecular separation but had no effects on cortical bone. Dexamethasone treatment increased trabecular bone separation, cortical marrow area, and cortical bone periosteal perimeter. Mice treated with l-asparaginase did not have any bone phenotypes. In conclusion, these data indicate that the majority of the chemotherapy agents used in induction therapy for pediatric ALL have long-term effects on bone in mice. A single dose of doxorubicin in juvenile mice was sufficient to cause the majority of the bone phenotypes, with combination therapy intensifying these effects.

Mapping and targeting of the leukemic microenvironment

Numerous studies support a role of the microenvironment in maintenance of the leukemic clone, as well as in treatment resistance. It is clear that disruption of the normal bone marrow microenvironment is sufficient to promote leukemic transformation and survival in both a cell autonomous and non-cell autonomous manner. In this review, we provide a snapshot of the various cell types shown to contribute to the leukemic microenvironment as well as treatment resistance. Several of these studies suggest that leukemic blasts occupy specific cellular and biochemical "niches." Effective dissection of critical leukemic niche components using single-cell approaches has allowed a more precise and extensive characterization of complexity that underpins both the healthy and malignant bone marrow microenvironment. Knowledge gained from these observations can have an important impact in the development of microenvironment-directed targeted approaches aimed at mitigating disease relapse.

Acute lymphoblastic leukaemia with osteolytic bone lesions: diagnostic dilemma

A previously healthy 37-year-old man presented with a 10-month history of intractable back pain. On examination, there was tenderness to palpation along lower thoracic and lumbar spine. Complete blood count showed mild anaemia but was otherwise unremarkable. Imaging studies revealed compression deformities with multiple osteolytic lesions involving multiple levels of the thoracic and lumbar spine. Bone marrow aspiration and biopsy were performed and demonstrated blast cells involving 80% of the bone marrow cellularity. Findings on flow cytometry were consistent with B-lymphoblastic leukaemia. He was subsequently started on hyper-CVAD (fractionated cyclophosphamide, vincristine, Adriamycin and dexamethasone) induction chemotherapy.

Late Effects of Therapy in Childhood Acute Lymphoblastic Leukemia Survivors

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

The Bone Marrow Microenvironment in Health and Myeloid Malignancy

Hematopoietic stem cells (HSCs) interact dynamically with an intricate network of cells in the bone marrow (BM) microenvironment or niche. These interactions provide instructive cues that influence the production and lineage determination of different types of blood cells and maintenance of HSC quiescence. They also contribute to hematopoietic deregulation and hematological myeloid malignancies. Alterations in the BM niche are commonly observed in myeloid malignancies and contribute to the aberrant function of myelodysplastic and leukemia-initiating stem cells. In this work, we review how different components of the BM niche affect normal hematopoiesis, the molecular signals that govern this interaction, and how genetic changes in stromal cells or alterations in remodeled malignant BM niches contribute to myeloid malignancies. Understanding the intricacies between normal and malignant niches and their modulation may provide insights into developing novel therapeutics for blood disorders.

Physical training interventions for children and teenagers affected by acute lymphoblastic leukemia and related treatment impairments

A decreased physical fitness has been reported in patients and survivors of acute lymphoblastic leukemia (ALL). This is influenced by the negative effects of the disease and by the treatments of childhood cancer.

In the past, children were advised to recover in bed, and to take as much relax as possible. Nowadays, it is considered that too much immobility may result in a further decrease of physical fitness and functioning. Exercise training for ALL children has frequently been reported to improve physical fitness and the well-being of the children, since it prevents the negative effects of a sedentary life-style, such as obesity and a poor skeletal health. In recent years, different studies and protocols on this subject has become available for children and young adults with cancer, both during and after treatment.

The efficacy of recent physical exercise training interventions, that act on several ALL impairments in children such as skeletal, musculoskeletal, neuromuscular, cardiopulmonary and cardiovascular systems, fatigue, body balance disorders and metabolism alterations have been examined.

These side effects might be prevented or significantly reduced by introducing a physical exercise program during or shortly after cancer treatment. Several interventions are discussed and presented for each impairment, reducing their level caused by the disease and thus suggesting the importance of physical training activity in ameliorating the children quality of life.

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

Objective:

To evaluate the impact of therapy on bone mineral density (BMD) and body composition in survivors of acute lymphoblastic leukemia (ALL) treated in accordance with Brazilian protocols by the Brazilian Cooperative Group of Treatment of Lymphoblastic Leukemia in Childhood (GBTLI) LLA-93 and LLA-99.

Methods:

A cross-sectional study with 101 patients was performed. BMD and body composition were evaluated using bone densitometry and were interpreted according to the age group and the reference population. Values between -1.1 and -1.9 in the group of children under 20 years were considered as risk group for low BMD z-scores. BMD values were compared to clinical characteristics, treatment received and body composition. A chi-square test, Fisher’s exact test, likelihood ratio and Student’s t-test were applied, with a 5% significance level.

Results:

The patients presented a frequency of fractures of 2%, of osteonecrosis, 2%, and of low BMD, 2.9%. In the group of 79 patients under 20 years of age, three had low BMD. The 16 that presented risk for low BMD, demonstrated lower valutes in lumbar vertebrae L1-L4 (p=0.01) and whole body (p=0.005), and smaller values of lean body mass (p=0.03). In the group of 22 patients over 20 years of age, ten had osteopenia.

Conclusions:

The low impact of treatment on BMD of this study confirms the concept that the bone mass gain occurs with increasing age and that the treatment does not influence the process. The population at risk for low BMD values presented lower bone mass values and could benefit from a long-term monitoring for possible bone toxicity.

Atypical Presentation of Acute Lymphoblastic Leukemia in a 7 Year Old Child

Seven year child, who had intussusception 4 month before, readmitted for fever and walking difficulty. On examination, child had mild pallor and kyphosis of the spine but no organomegaly, lymphadenopathy or bone pain . Further evaluation revealed hypercalcemia, diffuse osteoporosis with vertebral fracture. Peripheral smear showed no blasts or pancytopenia. Bone marrow aspiration turned out to be a pre B cell ALL. This child had many atypical presentations like intussusception, osteoporosis, vertebral collapse and hypercalcemia without any classical features of ALL.

Potential Effects of Phytoestrogen Genistein in Modulating Acute Methotrexate Chemotherapy-Induced Osteoclastogenesis and Bone Damage in Rats

Chemotherapy-induced bone damage is a frequent side effect which causes diminished bone mineral density and fracture in childhood cancer sufferers and survivors. The intensified use of anti-metabolite methotrexate (MTX) and other cytotoxic drugs has led to the need for a mechanistic understanding of chemotherapy-induced bone loss and for the development of protective treatments. Using a young rat MTX-induced bone loss model, we investigated potential bone protective effects of phytoestrogen genistein. Oral gavages of genistein (20 mg/kg) were administered daily, for seven days before, five days during, and three days after five once-daily injections (sc) of MTX (0.75 mg/kg). MTX treatment reduced body weight gain and tibial metaphyseal trabecular bone volume (p < 0.001), increased osteoclast density on the trabecular bone surface (p < 0.05), and increased the bone marrow adipocyte number in lower metaphyseal bone (p < 0.001). Genistein supplementation preserved body weight gain (p < 0.05) and inhibited ex vivo osteoclast formation of bone marrow cells from MTX-treated rats (p < 0.001). However, MTX-induced changes in bone volume, trabecular architecture, metaphyseal mRNA expression of pro-osteoclastogenic cytokines, and marrow adiposity were not significantly affected by the co-administration of genistein. This study suggests that genistein may suppress MTX-induced osteoclastogenesis; however, further studies are required to examine its potential in protecting against MTX chemotherapy-induced bone damage.

Late effects of childhood cancer and its treatment

Treatment for childhood cancer with chemotherapy, radiation and/or hematopoietic cell transplant can result in adverse sequelae that may not become evident for many years. A clear understanding of the association between therapeutic exposures and specific long-term complications, and an understanding of the magnitude of the burden of morbidity borne by childhood cancer survivors, has led to the development of guidelines to support lifelong risk-based follow up for this population. It is important to develop interventions to reduce the impact of treatment-related late effects on morbidity and mortality and to continue research regarding the etiopathogenesis of therapy-related cancers and other late effects.

Inhibition of leukemia cell engraftment and disease progression in mice by osteoblasts

The bone marrow niche is thought to act as a permissive microenvironment required for emergence or progression of hematologic cancers. We hypothesized that osteoblasts, components of the niche involved in hematopoietic stem cell (HSC) function, influence the fate of leukemic blasts. We show that osteoblast numbers decrease by 55% in myelodysplasia and acute myeloid leukemia patients. Further, genetic depletion of osteoblasts in mouse models of acute leukemia increased circulating blasts and tumor engraftment in the marrow and spleen leading to higher tumor burden and shorter survival. Myelopoiesis increased and was coupled with a reduction in B lymphopoiesis and compromised erythropoiesis, suggesting that hematopoietic lineage/progression was altered. Treatment of mice with acute myeloid or lymphoblastic leukemia with a pharmacologic inhibitor of the synthesis of duodenal serotonin, a hormone suppressing osteoblast numbers, inhibited loss of osteoblasts. Maintenance of the osteoblast pool restored normal marrow function, reduced tumor burden, and prolonged survival. Leukemia prevention was attributable to maintenance of osteoblast numbers because inhibition of serotonin receptors alone in leukemic blasts did not affect leukemia progression. These results suggest that osteoblasts play a fundamental role in propagating leukemia in the marrow and may be a therapeutic target to induce hostility of the niche to leukemia blasts.

Osteoporosis resulting from acute lymphoblastic leukemia in a 7-year-old boy: a case report

Introduction

Osteoporosis in children is rare and usually secondary to an underlying disease process whose diagnosis may be difficult to detect. Etiological factors responsible for osteoporosis secondary to chronic illness include immobility, pubertal delay and other hormonal disturbances. Rarely, it can be a manifestation of acute lymphoblastic leukemia. Most of the reported bone fracture incidences associated with acute lymphoblastic leukemia occur during the course of the chemotherapy, not at the point of the first symptoms of leukemic disease, as happened with the case presented here.

Case presentation

A 7-year-old Asian Balinese boy presented with back pain. His anteroposterior pelvic radiograph showed osteoporotic bone. A bone age study revealed growth failure of his metacarpals, phalanges and sesamoid. His total bone mass density was 97% age-match. However, a peripheral blood smear showed normochromic anemia with thrombocytopenia. Immunophenotyping of his peripheral blood revealed no dominant markers, but a bone marrow aspiration confirmed a diagnosis of acute lymphoblastic leukemia.

Conclusions

Osteoporosis was the only manifestation of the child’s underlying acute lymphoblastic leukemia. Leukemia was diagnosed when his bone marrow was found to contain more than 25% blasts. Because of leucopenia, the immunophenotype failed to reveal a dominant marker in this case, thus we were unable to classify the acute lymphoblastic leukemia.

Fit4Life: a weight loss intervention for children who have survived childhood leukemia

BACKGROUND

Children surviving acute lymphoblastic leukemia (ALL) are at increased risk for overweight and obesity over that of the general population. Whether a generic or tailored approach to weight management is needed for cancer survivors has yet to be tested.

PROCEDURE

Thirty-eight youth 8-18 years with BMI ≥ 85% who had survived ALL were recruited for a randomized clinical trial evaluating a weight management intervention (WMI) tailored for childhood ALL survivors (Fit4Life). Fit4Life recipients received a 4-month web, phone, and text message-delivered WMI tailored for cancer survivorship. Controls received a general WMI delivered via phone and mail. Assessments were performed at baseline and 4 months. Outcome data were analyzed according to assigned treatment condition over time.

RESULTS

Most (80%, (70%, 100%) [median (IQR)]) of the assigned curriculum was received by Fit4Life participants as compared to 50% (40%, 65%) among controls. Fit4Life recipients ≥ 14 years demonstrated less weight gain (P = 0.05) and increased moderate-to-vigorous physical activity (P < 0.01) while all Fit4Life recipients reported reduced negative mood (P < 0.05) over time as compared to control counterparts.

CONCLUSIONS

We demonstrated acceptable feasibility of a WMI tailored for overweight and obese children surviving ALL utilizing a multimodal technology approach. Improved weight, weight-related behavior, and psychological outcomes were demonstrated among Fit4Life intervention as compared to youth receiving a generic WMI. Data from this pilot trial may be used to design a larger trial to determine whether youth of all ages also can derive a benefit from a cancer survivor-tailored WMI and whether short-term outcomes translate into improved long-term outcomes for childhood ALL survivors.

Efficacy of pamidronate in children with low bone mineral density during and after chemotherapy for acute lymphoblastic leukemia and non-Hodgkin lymphoma

Background

Reduced bone mineral density (BMD) is a significant sequelae in children receiving chemotherapy for acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma (NHL). Reduced BMD is associated with an increased risk for fractures. Pamidronate, a second-generation bisphosphonate, has been used to treat osteoporosis in children. This study evaluated the safety and efficacy of pamidronate in children with low BMD during and after chemotherapy for ALL and NHL.

Methods

Between April 2007 and October 2011, 24 children with ALL and NHL were treated with pamidronate. The indication was a decreased BMD Z-score less than -2.0 or bone pain with a BMD Z-score less than 0. Pamidronate was infused at 1 mg/kg/day for 3 days at 1-4 month intervals (pamidronate group, cases). The BMD Z-scores of the cases were compared with those of 10 untreated patients (control group). Lumbar spine BMDs were measured every 6 cycles using dual energy X-ray absorptiometry and Z-scores were calculated. Bone turnover parameters (25-hydroxyvitamin D, alkaline phosphatase, parathyroid hormone, osteocalcin, and type I collagen c-terminal telopeptide) were analyzed.

Results

The median cycle of pamidronate treatment was 12. Increases in BMD Z-scores were significantly higher in the pamidronate group than in the control group (P<0.001). BMD (mg/cm²) increased in all pamidronate-treated cases. Twenty patients who complained of bone pain reported pain relief after therapy. The treatment was well tolerated.

Conclusion

Pamidronate appears to be safe and effective for the treatment of children with low BMD during and after chemotherapy for ALL and NHL.

Increased uptake of social security benefits among long-term survivors of cancer in childhood, adolescence and young adulthood: a Norwegian population-based cohort study

BACKGROUND

As the number of cancer survivors increases, their health and welfare have come into focus. Thus, long-term medical consequences of cancer at a young age (<25 years), obtained from social security benefit records, were studied.

METHODS

Standardised incidence ratios (SIRs) of long-term medical consequences for 5-year cancer survivors, born during 1965-1985, were explored by linking population-based registries in Norway.

RESULTS

Among the 5-year cancer survivors (4031 individuals), 29.7% received social security benefits. The survivors had an overall 4.4 times (95% confidence interval (95% CI): 4.1-4.6) higher risk of social security benefit uptake than the cancer-free population. Survivors of malignancies of bone and connective tissues (SIR: 10.8; 95% CI: 9.1-12.9), CNS tumours (SIR: 7.7; 95% CI: 6.9-8.6) and malignancies of the haematopoietic system (SIR: 6.1; 95% CI: 5.3-7.0) had the highest risks of social security benefits uptake. The most notified causes of social security benefit uptake were diseases of the nervous system, and injury and poisoning.

CONCLUSION

The uptake of social security benefits among 5-year cancer survivors increased substantially and it may represent a solid outcome measure for the burden of the most severe late effects, especially in countries with comparable social welfare systems.

Bone mineral density deficits in childhood cancer survivors: Pathophysiology, prevalence, screening, and management

As chemotherapy and other sophisticated treatment strategies evolve and the number of survivors of long-term childhood cancer grows, the long-term complications of treatment and the cancer itself are becoming ever more important. One of the most important but often neglected complications is osteoporosis and increased risk of fracture during and after cancer treatment. Acquisition of optimal peak bone mass and strength during childhood and adolescence is critical to preventing osteoporosis later in life. However, most childhood cancer patients have multiple risk factors for bone mineral loss. Cancer itself, malnutrition, decreased physical activity during treatment, chemotherapeutic agents such as steroids, and radiotherapy cause bone mineral deficit. Furthermore, complications such as growth hormone deficiency and musculoskeletal deformity have negative effects on bone metabolism. Low bone mineral density is associated with fractures, skeletal deformity, pain, and substantial financial burden not only for childhood cancer survivors but also for public health care systems. Thus, it is important to monitor bone health in these patients and minimize their risk of developing osteoporosis and fragility fractures later in life.

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.

Prevention of bone growth defects, increased bone resorption and marrow adiposity with folinic acid in rats receiving long-term methotrexate

The underlying pathophysiology for bone growth defects in paediatric cancer patients receiving high dose methotrexate chemotherapy remains unclear and currently there are no standardized preventative treatments for patients and survivors. Using a model in young rats, we investigated damaging effects of long-term treatment with methotrexate on growth plate and metaphyseal bone, and the potential protective effects of antidote folinic acid. This study demonstrated that chronic folinic acid supplementation can prevent methotrexate-induced chondrocyte apoptosis and preserve chondrocyte columnar arrangement and number in the growth plate. In the metaphysis, folinic acid supplementation can preserve primary spongiosa heights and secondary spongiosa trabecular volume by preventing osteoblasts from undergoing apoptosis and suppressing methotrexate-induced marrow adiposity and osteoclast formation. Systemically, plasma of folinic acid supplemented rats, in comparison to plasma from rats treated with MTX alone, contained a significantly lower level of IL-1β and suppressed osteoclast formation in vitro in normal bone marrow cells. The importance of IL-1β in supporting plasma-induced osteoclast formation was confirmed as the presence of an anti-IL-1β neutralizing antibody attenuated the ability of the plasma (from MTX-treated rats) in inducing osteoclast formation. Findings from this study suggest that folinic acid supplementation during chronic methotrexate treatment can alleviate growth plate and metaphyseal damages and therefore may be potentially useful in paediatric patients who are at risk of skeletal growth suppression due to chronic methotrexate chemotherapy.

Attenuated Wnt/β-catenin signalling mediates methotrexate chemotherapy-induced bone loss and marrow adiposity in rats

Cancer chemotherapy often causes significant bone loss, marrow adiposity and haematopoietic defects, yet the underlying mechanisms and recovery potential remain unclear. Wnt/β-catenin signalling is integral to the regulation of osteogenesis, adipogenesis and haematopoiesis; using a rat model, the current study investigated roles of this signalling pathway in changes to bone marrow stromal and haematopoietic cell differentiation after chemotherapy with methotrexate (MTX), a commonly used antimetabolite. MTX treatment in rats (5 daily administrations at 0.75 mg/kg) has previously been found to decrease bone volume and increase marrow fat, which was associated with increased osteoclastogenesis in haematopoietic cells and with an osteogenesis to adipogenesis switch in bone marrow stromal cells of treated rats. In the current study, on day 6 after the first MTX dose we found that accompanying these changes as well as a suppressed haematopoietic cellularity but increased granulocyte/macrophage differentiation potential, there was an increase in mRNA expression of Wnt antagonists sFRP-1 and Dkk-1 in bone, a reduction in nuclear β-catenin protein in bone marrow stromal cells, and decreased mRNA levels of β-catenin target genes lef-1, cyclin D1 and survivin, suggesting reduced activation of Wnt/β-catenin signalling in the bone during MTX-induced damage. Concurrent administration of BIO, a GSK-3β inhibitor that stabilises β-catenin, partially abrogated the MTX-induced transient changes in osteogenic/adipogenic commitment, granulocyte/macrophage lineage differentiation and osteoclast number. These findings demonstrate a potentially important role of Wnt/β-catenin signalling in MTX chemotherapy-induced cellular changes to the bone marrow microenvironment.

Cardiac response to doxorubicin and dexrazoxane in intact and ovariectomized young female rats at rest and after swim training

The impact of cancer therapies on adult cardiac function is becoming a concern as more children survive their initial cancer. Cardiovascular disease is now a significant problem to adult survivors of childhood cancer. Specifically, doxorubicin (DOX) may be particularly harmful in young girls. The objective of this study was to characterize DOX damage and determine the ability of dexrazoxane (DEX) to reduce DOX-mediated cardiac damage in sedentary and swim-trained female rats. Female Sprague-Dawley rats were left intact or ovariectomized (OVX) at weaning then injected with DEX (60 mg/kg) before DOX (3 mg/kg), DOX alone, or PBS. Rats were separated into sedentary and swim cohorts. Body weight was reduced in DOX:DEX- but not PBS- or DOX-treated rats. Echocardiographic parameters were similar in sedentary rats. Swim training revealed greater concentric remodeling in DOX-treated rats and reduced fractional shortening in DOX:DEX-treated rats. Calsequestrin 2 was reduced with DOX and increased with DOX:DEX postswim. Sarco(endo)plasmic reticulum Ca2+-ATPase 2a was reduced and calsequestrin 2 reduced further by swim training only in intact rats. OVX rats were heavier and developed eccentric remodeling post-swim with DOX and eccentric hypertrophy with DOX:DEX. Changes in SERCA2a and calsequestrin 2 expression were not observed. Ovariectomized DOX- and DOX:DEX-treated rats stopped growing during swim training. DEX coinjection did not relieve DOX-mediated cardiotoxicity in intact or hormone-deficient rats. DOX-mediated reductions in growth, cardiac function, and expression of calcium homeostasis proteins were exacerbated by swim. DEX coadministration did not substantially relieve DOX-mediated cardiotoxicity in young female rats. Ovarian hormones reduce DOX-induced cardiotoxicity.

Methotrexate chemotherapy reduces osteogenesis but increases adipogenic potential in the bone marrow

Intensive use of cancer chemotherapy is increasingly linked with long-term skeletal side effects such as osteopenia, osteoporosis and fractures. However, cellular mechanisms by which chemotherapy affects bone integrity remain unclear. Methotrexate (MTX), used commonly as an anti-metabolite, is known to cause bone defects. To study the pathophysiology of MTX-induced bone loss, we examined effects on bone and marrow fat volume, population size and differentiation potential of bone marrow stromal cells (BMSC) in adult rats following chemotherapy for a short-term (five once-daily doses at 0.75 mg/kg) or a 6-week term (5 doses at 0.65 mg/kg + 9 days rest + 1.3 mg/kg twice weekly for 4 weeks). Histological analyses revealed that both acute and chronic MTX treatments caused a significant decrease in metaphyseal trabecular bone volume and an increase in marrow adipose mass. In the acute model, proliferation of BMSCs significantly decreased on days 3-9, and consistently the stromal progenitor cell population as assessed by CFU-F formation was significantly reduced on day 9. Ex vivo differentiation assays showed that while the osteogenic potential of isolated BMSCs was significantly reduced, their adipogenic capacity was markedly increased on day 9. Consistently, RT-PCR gene expression analyses showed osteogenic transcription factors Runx2 and Osterix (Osx) to be decreased but adipogenic genes PPARγ and FABP4 up-regulated on days 6 and 9 in the stromal population. These findings indicate that MTX chemotherapy reduces the bone marrow stromal progenitor cell population and induces a switch in differentiation potential towards adipogenesis at the expense of osteogenesis, resulting in osteopenia and marrow adiposity.

Deregulation of the CXCL12/CXCR4 axis in methotrexate chemotherapy-induced damage and recovery of the bone marrow microenvironment

Cancer chemotherapy disrupts the bone marrow (BM) microenvironment affecting steady-state proliferation, differentiation and maintenance of haematopoietic (HSC) and stromal stem and progenitor cells; yet the underlying mechanisms and recovery potential of chemotherapy-induced myelosuppression and bone loss remain unclear. While the CXCL12/CXCR4 chemotactic axis has been demonstrated to be critical in maintaining interactions between cells of the two lineages and progenitor cell homing to regions of need upon injury, whether it is involved in chemotherapy-induced BM damage and repair is not clear. Here, a rat model of chemotherapy treatment with the commonly used antimetabolite methotrexate (MTX) (five once-daily injections at 0.75 mg/kg/day) was used to investigate potential roles of CXCL12/CXCR4 axis in damage and recovery of the BM cell pool. Methotrexate treatment reduced marrow cellularity, which was accompanied by altered CXCL12 protein levels (increased in blood plasma but decreased in BM) and reduced CXCR4 mRNA expression in BM HSC cells. Accompanying the lower marrow CXCL12 protein levels (despite its increased mRNA expression in stromal cells) was increased gene and protein levels of metalloproteinase MMP-9 in bone and BM. Furthermore, recombinant MMP-9 was able to degrade CXCL12 in vitro. These findings suggest that MTX chemotherapy transiently alters BM cellularity and composition and that the reduced cellularity may be associated with increased MMP-9 expression and deregulated CXCL12/CXCR4 chemotactic signalling.

Skeletal morbidity in children receiving chemotherapy for acute lymphoblastic leukemia and its association with mineral homeostasis and duration of inpatient stay

BACKGROUND

Reduced activity, older age, and abnormal bone mineral status are considered as important determinants of poor bone health in children with acute lymphoblastic leukemia (ALL). The independent contribution of these factors toward skeletal morbidity (SM) requires further investigation.

AIM

The aim of this study was to investigate the influence of activity, age, and mineral status over the first 12 months of chemotherapy on subsequent SM.

PATIENTS AND METHODS

The medical records of 56 children presenting with ALL between 2003 and 2007 and treated on UKALL2003 were reviewed for the number of inpatient days over the first 12 months of chemotherapy as a surrogate marker of inactivity and lack of well-being. Data for serum Ca, albumin, Mg, and Pho were also collected over this period. SM was defined as any episode of musculoskeletal pain or fractures.

RESULTS

The median duration of inpatient days over the first 12 months of treatment in children with no SM was 58 days (40,100), whereas the median number of inpatient days during the first 12 months in those children with any SM, musculoskeletal pain only, or fractures only was 83 days (54,131), 81 days (52,119) and 91 days (59,158), respectively (P=0.003). Children with SM and fractures particularly had lower levels of serum Ca, Mg, and Pho compared with those without SM over the first 12 months of chemotherapy. There was a higher risk of SM in those who were diagnosed after the age of 8 years (P=0.001, odds ratio=16, 95% confidence interval: 3.80). Multiple regression analysis showed that the incidence of SM only had a significant independent association with age at diagnosis (P=0.001) and the number of inpatient days (P=0.03) over the first 12 months (r=23). All children who were diagnosed after the age of 8 years with an inpatient stay of more than 75 days, in the first 12 months of the chemotherapy (n,14) children had some form of SM (odds ratio=64).

CONCLUSIONS

The incidence of SM in children receiving chemotherapy for ALL is associated with a higher likelihood of being older and having longer periods of inpatient stay. The close link between age and changes in bone mineral status may be one explanation for the increased bone morbidity in ALL children.

Feasibility and parent satisfaction of a physical therapy intervention program for children with acute lymphoblastic leukemia in the first 6 months of medical treatment

BACKGROUND

Children with acute lymphoblastic leukemia (ALL) are at risk for developing musculoskeletal complications during and after their medical treatment. The objective of this study was to examine the feasibility of an in-hospital physical therapy- and home exercise program during the first four phases of medical treatment, for children with newly diagnosed ALL.

PROCEDURE

Nine patients, between the ages of 2-14 years old were enrolled within 2 weeks of diagnosis in the study. Each patient was evaluated at study entry, after each of the first four phases of therapy and each time patients were re-admitted to the hospital. Following the initial physical therapy evaluation an individualized home exercise program was developed, consisting of stretching, strengthening, and aerobic exercises. The following end points were measured at each evaluation: gross motor assessment as measured by gross motor function measure (GMFM), health-related quality of life as measured by the PedsQL and parent satisfaction questionnaire.

RESULTS

This study was feasible with 98% of the evaluation sessions completed. The GMFM and PedsQL improved steadily throughout the study; however, the PedsQL slightly decreased from interim maintenance to delayed intensification. The parents reported being satisfied with the physical therapy program.

CONCLUSION

We demonstrated that an in-hospital- and home exercise physical therapy program during the first four phases of medical treatments is feasible for children with ALL. Future randomized studies are needed to confirm whether an initial physical therapy program at diagnosis in children with ALL will limit functional impairments, improve overall fitness and increase health-related quality of life.

Initial presentation of acute lymphoblastic leukemia with osteoporosis and multiple spontaneous bone fractures

Acute lymphoblastic leukemia (ALL) is the most common childhood malignancy. Skeletal abnormalities have been described in association with ALL including osteoprosis and bone fractures. Different factors including the disease itself or soluble products of malignant cells and treatment agents like cytotoxic drugs, methotroxate, corticosteroids and radiotherapy may be responsible for defective bone homeostasis in these patients. Orthopedic conditions and pain may be the first manifestation of acute leukemia and it is important for physicians to recognize the skeletal manifestation of acute childhood leukemia because of a delay in diagnosis has adverse effect on survival. We present a child with ALL that refer with multi bone fractures as a first manifestation of the disease.

Physician referral frequency for physical therapy in children with acute lymphoblastic leukemia

Children with acute lymphoblastic leukemia (ALL) are at risk for developing musculoskeletal complications. Few studies have examined the role of physical therapy (PT) for addressing these complications. The study objective was to examine why and when in the medical treatment, children with ALL receive a referral to PT. Retrospective chart review of 35 children, diagnosed with ALL in 2006 and 2007 at Penn State Children's Hospital was carried out. A questionnaire was completed by 6 pediatric oncologists, to identify their referral patterns. The chart review demonstrated that 25 of the 35 patients had reports of musculoskeletal complications sometime during their treatment, but only 10 (30%) were referred to PT. The most common reason for referral was decreased functional mobility. Patients were referred evenly through all phases of therapy. Vincristine was reduced in 5 patients, the most common cause being peripheral neuropathy and foot drop. The majority (5/6) of the physicians reported that they "sometimes" refer patients to PT, through different phases of therapy, with 1/3 reporting all phases. The results show that although physicians identified the musculoskeletal complications, only a minority of patients were referred for PT. This supports the need for increasing the awareness of physicians about benefits of early integration of PT into the medical treatment.

Late effects in long-term survivors after treatment for childhood acute leukemia

BACKGROUND

This is a report of late effects in childhood cancer survivors seen in the follow-up clinic of a single institution.

MATERIALS AND METHODS

There were 324 acute leukemia survivors in the database of the Long Term Follow Up Clinic of Children's National Medical Center from January 1, 1997, through June 30, 2005.

RESULTS

Of the 324 acute leukemia survivors, 228 were white, 48 black, 20 Hispanic, and 12 other. Their follow-up time was 0 to 25 years (mean 5.3 years). One or more adverse events occurred in 74.1% of the 324 survivors. Defective physical growth was most commonly reported, followed by disturbed neurocognitive function, emotional difficulties, cardiac abnormalities, hypertension, osteoporosis/osteopenia, fractures, and second neoplasms. More black and Hispanic children had acute myeloid leukemia, relapses, cardiac problems, and hypertension than white and other subjects.

CONCLUSION

Childhood cancer survivors require lifelong monitoring, with prompt identification and treatment of adverse late effects.

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.

Some musculo-skeletal sequelae in cancer survivors

This paper deals with some of the musculo-skeletal complication that can occur after cancer treatment. In particular, we focus on Cancer Treatment Induced Bone Loss (CTIBL) and the musculo-skeletal complications that can occur in patients treated for extremity sarcoma. In addition we discuss peripheral neuropathy, musculo-skeletal pain and briefly mention some of the complications related to radiotherapy. CTIBL is mostly studied in breast cancer and prostate cancer survivors. The cause in these groups is mainly due to treatment induced hypogonadism. Other causes of CTIBL are indirect or direct cause of chemotherapy, physical inactivity and inadequate intake of vitamin D and calcium. Treatment of CTIBL consists of diet and lifestyle changes and pharmacological intervention. Extremity bone sarcomas constitute a special group since they often experience mutilating surgery and heavy combination chemotherapy. The treatment results in worse function than the normal population and the amputated usually have lower physical functioning than patients treated with limb sparing surgery (LSS). However, most studies fail to show differences in quality of life between the amputated and LSS. Most of the studies performed on musculo-skeletal sequelae have been done on survivors of childhood cancer, breast cancer or prostate cancer. More studies among the other cancer groups are needed to reveal the extent and prevalence of these complications.

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 osteoporosis in pediatric patients after stem cell transplant

As more patients are surviving the transplant experience, more children are coping with long-term side effects. Long-term side effects, such as osteopenia and osteoporosis, are not as well acknowledged in pediatric stem cell transplant survivors. Osteopenia and osteoporosis can lead to fractures, deformities, pain, and financial burden. There are many factors during and after a stem cell transplant that cause patients to be at an increased risk for osteopenia or osteoporosis. Nurses have the ability to prevent these potentially debilitating and progressive diseases and to provide adequate treatment to prevent further complications. Key features of the history, physical examination, and diagnostic imaging can assist with making a diagnosis of osteoporosis or osteopenia. Prevention of osteopenia and osteoporosis involves both lifestyle modifications and medical management. Measures to prevent and treat bone loss are crucial. Transplant nurses must be knowledgeable regarding the risk factors and prevention and treatment strategies for osteopenia and osteoporosis.

The effects of medications on bone

Medications taken for the treatment of arthritis and psychotropic and epileptic disorders, as well as anticoagulants, antacids, bisphosphonates, corticosteroids, and antineoplastic drugs, can profoundly affect bone metabolism. In some scenarios (eg, osteoporosis), these effects are intended; in others (eg, rickets, osteomalacia secondary to antiepileptic drugs), potentially adverse side effects of medications on bone may occur. Nonsteroidal anti-inflammatory drugs appear to delay fracture healing and bone ingrowth, although these effects are reversible. Disease-modifying antirheumatic drugs do not appear to affect bone metabolism adversely when taken in the low dosages currently prescribed. Bisphosphonates are useful in restoring bone mass in cases of postmenopausal osteoporosis, glucocorticoid-induced osteoporosis, Paget's disease, and neoplastic conditions with bone loss and hypercalcemia. Corticosteroids and cancer chemotherapeutic agents generally affect bone adversely and increase fracture risk.