Bone morbidity in pediatric acute lymphoblastic leukemia

Genome-wide study identifies novel genes associated with bone toxicities in children with acute lymphoblastic leukaemia

Bone toxicities are common among paediatric patients treated for acute lymphoblastic leukaemia (ALL) with potentially major negative impact on patients' quality of life. To identify the underlying genetic contributors, we conducted a genome-wide association study (GWAS) and a transcriptome-wide association study (TWAS) in 260 patients of European-descent from the DFCI 05-001 ALL trial, with validation in 101 patients of European-descent from the DFCI 11-001 ALL trial. We identified a significant association between rs844882 on chromosome 20 and bone toxicities in the DFCI 05-001 trial (p = 1.7 × 10-8). In DFCI 11-001 trial, we observed a consistent trend of this variant with fracture. The variant was an eQTL for two nearby genes, CD93 and THBD. In TWAS, genetically predicted ACAD9 expression was associated with an increased risk of bone toxicities, which was confirmed by meta-analysis of the two cohorts (meta-p = 2.4 × 10-6). In addition, a polygenic risk score of heel quantitative ultrasound speed of sound was associated with fracture risk in both cohorts (meta-p = 2.3 × 10-3). Our findings highlight the genetic influence on treatment-related bone toxicities in this patient population. The genes we identified in our study provide new biological insights into the development of bone adverse events related to ALL treatment.

Evaluation of Bone Turnover Markers in Patients with Acute and Chronic Leukemia

This study investigated different bone biomarkers (cross-linked carboxy-terminal telopeptide of type 1 collagen (CTX-1), pyridinoline (PYD), osteocalcin (OC), interleukin-6 receptor (IL-6R), calcium (Ca), and magnesium (Mg)) in terms of their metabolism in 4 different leukemia subtypes (ALL, AML, CLL and CML). The design was case control study with 30 controls and 60 cases of leukemia patients. Authors have reported many results regarding decrease as well as increase of specific bone biomarker under investigation with each leukemia subtype when compared to control. In addition, Authors reported correlations between each biomarker level and leukemia subtypes.

Factors affecting bone mineral density in children and adolescents with systemic lupus erythematosus

PURPOSE

Patients with juvenile-onset systemic lupus erythematosus (JSLE) are at a high risk of entering adulthood with disease-related morbidities like reduced bone mass and osteoporosis. This study aimed to evaluate the clinical characteristics of JSLE and to analyze the factors associated with low bone mineral density (BMD) in these patients.

METHODS

Children and adolescents diagnosed with JSLE at a single institution in Korea were included. Demographic, clinical, and laboratory data as well as details about the use of glucocorticoids (GCs) and disease-modifying antirheumatic drugs were collected. The lumbar spine (LS) BMD z-score was measured using dual energy x-ray absorptiometry, and lateral thoracolumbar spine radiographs were collected.

RESULTS

A total of 29 patients with JSLE were included in this study. Of these patients, 7 had a BMD z-score of -2.0 or lower and were designated as the low BMD group. The differences in the clinical parameters and treatment variables between the low BMD and non-low BMD groups were compared. Higher cumulative GC dose, longer GC exposure, and higher cumulative hydroxychloroquine (HCQ) dose were all associated with low BMD; among them, the main factor was the duration of GC exposure. There was no significant correlation between BMD and clinical profile, disease activity, or bone-metabolism markers.

CONCLUSION

The duration of GC exposure, cumulative GC dose, and cumulative HCQ dose were risk factors for low BMD in patients with JSLE, with the main factor being the duration of GC exposure. Thus, patients with JSLE should be routinely monitored for low BMD and potential fracture risks, and GC-sparing treatment regimens should be considered.

The evolution of nutritional care in children and young people with acute lymphoblastic leukaemia: a narrative review

BACKGROUND

Acute lymphoblastic leukaemia (ALL) is the most common paediatric malignancy in the world. Advances in treatment protocols have resulted in survival rates of >80% in most high-income countries (HIC); however, children and young people (CYP) with ALL continue to face significant nutrition-related challenges during treatment.

METHODS

This narrative review outlines the changing landscape of treatment and survivorship for CYP with ALL and the advances in nutrition knowledge that call for changes to clinical nutrition practice.

RESULTS

The incidence of ALL has remained stable in HIC; however, there have been significant advances in survival over the past 30 years. Overweight and obesity are increasingly prevalent in CYP with ALL at diagnosis, during treatment and in survivorship. Coupled with poor diet quality, high-energy and saturated fat intakes, altered eating behaviours and inactivity, this necessitates the need for a shift in nutrition intervention. Undernutrition remains a concern for CYP with high-risk treatment protocols where oral or enteral nutrition support remains a cornerstone of maintaining nutrition status.

CONCLUSIONS

With improved treatment protocols and high survival rates, a shift to focusing on diet quality, prevention of excessive weight gain and obesity during treatment and survivorship is necessary.

Osteohematology: To be or Notch to be

Osteohematology is an emerging research field that studies the crosstalk between hematopoietic and bone stromal cells, to elucidate the mechanisms of hematological and skeletal malignancies and diseases. The Notch is an evolutionary conserved developmental signaling pathway, with critical roles in embryonic development by controlling cell proliferation and differentiation. However, the Notch pathway is also critically involved in cancer initiation and progression, such as osteosarcoma, leukemia, and multiple myeloma. The Notch-mediated malignant cells dysregulate bone and bone marrow cells in the tumour microenvironment, resulting in disorders ranging from osteoporosis to bone marrow dysfunction. To date, the complex interplay of Notch signaling molecules in hematopoietic and bone stromal cells is still poorly understood. In this mini-review, we summarize the crosstalk between cells in bone and bone marrow and their influence under the Notch signaling pathway in physiological conditions and in tumour microenvironment.

A Causality between Thyroid Function and Bone Mineral Density in Childhood: Abnormal Thyrotropin May Be Another Pediatric Predictor of Bone Fragility

Low bone mass can occur in children and adolescents with numerous chronic conditions; however, the influence of abnormal thyroid hormone and thyroid-stimulating hormone (TSH) levels on low bone mineral density (BMD) in children and adolescents remains controversial. Investigating the effects of excessive or deficient thyroid hormone and TSH levels on the risk of childhood bone fragility may provide a better understanding of the role of thyroid function on bone density in the pediatric population. The triiodothyronine (T3), thyroxine (T4), and TSH levels and BMD of 619 children diagnosed with various underlying conditions and whose treatment was completed were simultaneously assessed. The T3, free thyroxine (FT4), and TSH levels were subcategorized based on the age-matched reference range, and the lumbar spine BMD (LSBMD) data were compared. The mean LSBMD z-score was 0.49 ± 1.28, while T3, FT4, and TSH levels were 1.25 ± 0.29 ng/mL, 1.28 ± 0.19 ng/dL, and 2.76 ± 1.87 µU/mL, respectively. Both lumbar and femoral BMD z-scores were lower in children with abnormal TSH levels. TSH abnormality was the strongest risk factor for decreased LSBMD z-scores, and thus could be an early indicator of low BMD in children and adolescents with various underlying conditions.

Acute Lymphoblastic Leukemia presenting as a Pathologic Fibular Fracture

The authors present a case of a 2-year-old girl with left ankle pain. On examination, there was tenderness but no sign of superficial swelling, erythema, or deformity. Imaging studies revealed a heterogeneous lytic lesion in the distal diaphysis of the left fibula, causing a pathologic fracture. The patient was treated with ankle splinting, analgesia, and referred to a pediatric orthopedic physician. Ultimately the diagnosis of acute lymphoblastic leukemia (ALL) was made. The authors present the significance of discerning skeletal abnormalities and orthopedic pain as the initial manifestation of leukemia.

Physical Therapy Utilization Among Hospitalized Patients With Pediatric Acute Lymphoblastic Leukemia

PURPOSE

Patients with pediatric acute lymphoblastic leukemia (ALL) are at risk for impaired physical function from treatment. Early physical therapy (PT) may improve physical function and health in children with ALL, yet little is known about PT utilization in this population.

METHODS

Leveraging the Premier Healthcare Database, we conducted a cohort study including participants hospitalized with ALL at age 0-21 years from January 1, 2010, through March 31, 2017. A generalized mixed linear model assessed sociodemographic and clinical variables associated with receiving PT within 1 year of first hospitalization.

RESULTS

Among 5,488 pediatric ALL patients from 330 hospitals (median age 7 years, interquartile range = 4-14 years), only 27.2% overall and 58.9% with neuromuscular conditions received PT within a year of first ALL admission. In multivariable analysis, patients more likely to receive PT were age 10-14 years (odds ratio [OR] = 1.46; 95% CI, 1.20 to 1.76) or 15-21 years (OR = 1.66; 95% CI, 1.36 to 2.02) versus 0-4 years and Hispanic (OR = 1.27; 95% CI, 1.04 to 1.56) versus White. Patients less likely to receive PT were treated by a nonhematology/oncology pediatric (OR = 0.56; 95% CI, 0.46 to 0.70) or adult (OR = 0.50; 95% CI, 0.38 to 0.65) specialist versus a pediatric hematologist/oncologist and treated at a nonteaching hospital (OR = 0.53; 95% CI, 0.36 to 0.79) versus a teaching hospital.

CONCLUSION

Only 27.2% of pediatric ALL patients overall and 58.9% with neuromuscular conditions receive inpatient PT within a year of first ALL admission. Interventions to increase inpatient PT services to pediatric ALL patients and address disparities in PT utilization may improve the physical function and long-term health of survivors.

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.

Long-Term Effects of Pediatric Acute Lymphoblastic Leukemia Chemotherapy: Can Recent Findings Inform Old Strategies?

During the last few decades, pediatric acute lymphoblastic leukemia (ALL) cure rates have improved significantly with rates exceeding 90%. Parallel to this remarkable improvement, there has been mounting interest in the long-term health of the survivors. Consequently, modified treatment protocols have been developed and resulted in the reduction of many adverse long-term consequences. Nevertheless, these are still substantial concerns that warrant further mitigation efforts. In the current review, pediatric-ALL survivors’ late adverse events, including secondary malignant neoplasms (SMNs), cardiac toxicity, neurotoxicity, bone toxicity, hepatic dysfunction, visual changes, obesity, impact on fertility, and neurocognitive effects have been evaluated. Throughout this review, we attempted to answer a fundamental question: can the recent molecular findings mitigate pediatric-ALL chemotherapy’s long-term sequelae on adult survivors? For SMNs, few genetic predisposition factors have been identified including TP53 and POT1 variants. Other treatment-related risk factors have been identified such as anthracyclines’ possible association with breast cancer in female survivors. Cardiotoxicity is another significant and common adverse event with some germline variants been found, albeit with conflicting evidence, to increase the risk of cardiac toxicity. For peripheral neurotoxicity, vincristine is the primary neurotoxic agent in ALL regimens. Some germline genetic variants were found to be associated with the vincristine neurotoxic effect’s vulnerability. However, these were mainly detected with acute neuropathy. Moreover, the high steroid doses and prolonged use increase bone toxicity and obesity risk with some pharmacogenetic biomarkers were associated with increased steroid sensitivity. Therefore, the role of these biomarkers in tailoring steroid choice and dose is a promising research area. Future directions in pediatric ALL treatment should consider the various opportunities provided by genomic medicine. Understanding the molecular bases underlying toxicities will classify patients into risk groups and implement a closer follow-up to those at higher risk. Pharmacogenetic-guided dosing and selecting between alternative agents have proven their efficacy in the short-term management of childhood ALL. It is the right time to think about a similar approach for the life-long consequences on survivors.

Dynamic Changes of the Bone Marrow Niche: Mesenchymal Stromal Cells and Their Progeny During Aging and Leukemia

Mesenchymal stromal cells (MSCs) are a heterogenous cell population found in a wide range of tissues in the body, known for their nutrient-producing and immunomodulatory functions. In the bone marrow (BM), these MSCs are critical for the regulation of hematopoietic stem cells (HSC) that are responsible for daily blood production and functional immunity throughout an entire organism's lifespan. Alongside other stromal cells, MSCs form a specialized microenvironment BM tissue called "niche" that tightly controls HSC self-renewal and differentiation. In addition, MSCs are crucial players in maintaining bone integrity and supply of hormonal nutrients due to their capacity to differentiate into osteoblasts and adipocytes which also contribute to cellular composition of the BM niche. However, MSCs are known to encompass a large heterogenous cell population that remains elusive and poorly defined. In this review, we focus on deciphering the BM-MSC biology through recent advances in single-cell identification of hierarchical subsets with distinct functionalities and transcriptional profiles. We also discuss the contribution of MSCs and their osteo-adipo progeny in modulating the complex direct cell-to-cell or indirect soluble factors-mediated interactions of the BM HSC niche during homeostasis, aging and myeloid malignancies. Lastly, we examine the therapeutic potential of MSCs for rejuvenation and anti-tumor remedy in clinical settings.

Musculoskeletal impairments in children receiving intensive therapy for acute leukemia or undergoing hematopoietic stem cell transplant: A report from the Children's Oncology Group

BACKGROUND

Children receiving intensive chemotherapy for leukemia or undergoing hematopoietic stem cell transplant (HSCT) for solid tumors or leukemia are at risk for musculoskeletal (MSK) impairment from their underlying disease and from treatment. Data are limited on the incidence and nature of these disorders during intensive therapy. This study's objective was to provide a cross-sectional description of MSK impairments in this population.

PROCEDURE

Children with acute myeloid leukemia (AML), relapsed acute lymphoblastic leukemia (rALL), or undergoing HSCT were systematically assessed for MSK impairments as part of Children's Oncology Group study ACCL0934. Assessments occurred at study entry, at 2 months, and at 12 months and included evaluation for signs or symptoms of MSK impairment and the type, site, and diagnosis.

RESULTS

Six hundred three patients were included. MSK signs or symptoms were present in 48 (8.0%) children at study entry, 64 (13.5%) children at 2 months, and 40 (11.6%) children at 12 months. Arthralgia and/or gait abnormalities were the most common impairments; the knee was the most common site. Arthritis and tendonitis were both rare. Vincristine neuropathy, MSK impacts from central nervous system pathology, and bone or joint pain from underlying cancer were the most common diagnoses. Multivariate analysis demonstrated that having rALL (odds ratio [OR] 2.00, 95% CI 1.07-3.76, p = .03) or obesity (OR 2.10, 95% CI 1.12-3.95, p = .02) were risk factors for MSK impairment at study entry.

CONCLUSIONS

MSK impairments are common in this intensively treated patient population, especially in those with rALL and those who are obese.

Recent perspectives on the association between osteonecrosis and bone mineral density decline in childhood acute lymphoblastic leukemia

The attention to treatment-related toxicity has increased since the survival of children with acute lymphoblastic leukemia (ALL) has improved significantly over the past few decades. Intensive ALL treatment schedules including corticosteroids and asparaginase have been shown to give rise to skeletal abnormalities such as osteonecrosis and low bone mineral density (BMD), which may lead to debilitating sequelae in survivors. Although osteonecrosis and low BMD are different entities with suggested separate pathophysiological mechanisms, recent studies indicate that osteonecrosis is associated with accelerated BMD decline. Common underlying mechanisms for osteonecrosis and BMD decline are considered, such as an enhanced sensitivity to corticosteroids in children who suffer from both osteonecrosis and low BMD. In addition, restriction of weight-bearing activities, which is generally advised in patients with osteonecrosis, could aggravate BMD decline. This induces a clinical dilemma, since bone stimulation is important to maintain BMD but alternative interventions for osteonecrosis are limited. Furthermore, this recent finding of accelerated BMD decline in children with osteonecrosis emphasizes the need to develop effective preventive measures for osteonecrosis, which may include targeting BMD decline.

Effect of Vertebral Fracture on Auxological Profiles of Children Undergoing Acute Lymphoblastic Leukemia Treatment

Background: Acute lymphoblastic leukemia (ALL) is the most common pediatric malignancy, and children with ALL often experience skeletal morbidity such as vertebral fractures (VF) during and after ALL treatment. Among various treatment-associated factors that affect growth pattern, the presence of VF might trigger growth impairment. Objective: This study aimed to investigate the overall VF incidence following childhood ALL treatment and examined the association of VF with growth. Methods: Children diagnosed with ALL whose treatment was completed between 2 and 15 years of age and who were screened with lateral thoracolumbar spine radiographs were enrolled. Clinical data, including anthropometric parameters were obtained at leukemia diagnosis (LD), treatment completion (TC), and 12 months following TC while VF assessment were obtained at TC and 12 months following TC. Results: In total, 155 children were included, and height status was decreased, whereas weight and BMI status were increased throughout three observational points. VF incidence at TC was 18.7%. Height status were lower in children with VF at LD, TC, and 12 months following TC, while a greater height decline was observed during the treatment period. Age and height status at LD and average glucocorticoid (GC) dose were associated VF incidence at TC. The presence of VF was a significant risk factor of height decline during the treatment period. Conclusion: A substantial number of children experienced VF following ALL treatment completion, and the presence of VF might adversely affect auxological status in children. VF detection by routine surveillance throughout childhood ALL treatment is recommended to try to prevent compromised growth.

Acrophyseal growth arrest in a long-term survivor of acute lymphoblastic leukemia

Growth arrest at the secondary growth plate, also known as the acrophysis, is a rare phenomenon with only very few known published case reports. We report on a case of formation of ghost secondary ossification centers at the acrophyses of the knee joint in a 14-year-old female, who survived early childhood acute lymphoblastic leukemia. The patient suffered from severe side effects from both disease and subsequent treatment strategies with a 10-month immobilization period as a consequence at the age of 3 years. The ghost secondary ossification centers were encountered on radiographs and MRI 10 years later, when she presented for evaluation of chronic pain in her left knee related to sports activities, due to a meniscal cyst. Awareness of this phenomenon is nevertheless important, because it seems that endochondral bone growth recovery at the acrophyses might be different from recovery in physes, because we found no concomitant sequelae of growth arrest in the metaphyses.