Background: A cancer diagnosis and its treatment often disrupt a child’s and adolescent’s normal level of physical activity, which plays a vital role in their development and health. They are therefore often less physically active during treatment than before the diagnosis or compared to healthy peers. Today, there is no comprehensive overview of the safety, feasibility, clinical effectiveness, and potentially long-lasting impact of physical activity (PA) interventions in this population. Methods: We conducted a systematic review in PubMed according to PRISMA guidelines to evaluate studies on PA interventions during cancer treatment in children and adolescents up to 25 years of age. We used the Joanna Briggs Institute’s critical appraisal tools to assess the risk of bias. Due to the heterogeneity in interventions and outcomes, we used descriptive approaches only to present the results. Results: Half of the 21 included studies were randomized controlled trials (10/21). PA interventions were found to be safe and feasible when tailored to the patient’s age, treatment phase, and clinical condition. Most studies reported improvements in physical fitness, strength, and quality of life, with some reductions in fatigue. Variability in interventions and outcomes, along with small sample sizes and heterogeneous patient populations, made it difficult to draw clear conclusions. Conclusions: PA appears to be a feasible and, in terms of injuries, safe adjunct to cancer treatment in children and adolescents. Despite promising trends, further large-scale, multicenter trials with standardized protocols are needed to better establish the long-term benefits and optimal interventions.

Background: Dexamethasone is important in the treatment for pediatric acute lymphoblastic leukemia (ALL) but induces muscle atrophy with negative consequences for muscle mass, muscle strength, and functional abilities. The aim of this study was to establish the effect of a dexamethasone course on sarcopenia and physical frailty in children with ALL, and to explore prognostic factors.Methods: Patients with ALL aged 3–18 years were included during maintenance therapy. Patients had a sarcopenia/frailty assessment on the first day of (T1) and on the day after (T2) a 5‐day dexamethasone course. Sarcopenia was defined as low muscle strength in combination with low muscle mass. Prefrailty and frailty were defined as having two or ≥three of the following components, respectively: low muscle mass, low muscle strength, fatigue, slow walking speed, and low physical activity. Chi‐squared and paired t‐tests were used to assess differences between T1 and T2. Logistic regression models were estimated to explore patient‐ and therapy‐related prognostic factors for frailty on T2.Results: We included 105 patients, 61% were boys. Median age was 5.3 years (range: 3–18.8). At T1, sarcopenia, prefrailty, and frailty were observed in respectively 2.8%, 23.5%, and 4.2% of patients. At T2, the amount of patients with frailty had increased to 17.7% (p = 0.002), whereas the number of patients with sarcopenia and prefrailty remained similar. Higher ASMM (odds ratio [OR]: 0.49, 95% CI: 0.28–0.83), stronger handgrip strength (OR: 0.41, 95% CI: 0.22–0.77) and more physical activity minutes per day (OR: 0.98, 95% CI: 0.96–0.99) decreased the risk of frailty at T2. Slower walking performance (OR: 2, 95% CI: 1.2–3.39) increased the risk. Fatigue levels at T1 were not associated with frailty at T2.Conclusion: Physical frailty increased strikingly after a 5‐days dexamethasone course in children with ALL. Children with poor physical state at start of the dexamethasone course were more likely to be frail after the course.

Pediatric brain tumor survivors (PBTS) experience disease- and treatment-related sequelae. We aimed to investigate the occurrence of participation limitations, impairments in functioning, fatigue, and the association between patient, tumor- and treatment-related factors and these outcomes. Children (4–18 years) after treatment for a brain tumor between 2005 and 2014 at the Erasmus Medical Center, Rotterdam, the Netherlands, were eligible. The parent-reported Child and Family Follow-up Survey developed to measure participation and impairments in functioning in youth with acquired brain injury, was used. Fatigue was assessed using the Pediatric Quality of Life Inventory Multidimensional Fatigue Scale. Associations with patient, tumor- and treatment-related factors were explored using univariable analyses. Ninety-one PBTS (median age: 11.3 years [range: 9.5–14.1], time since treatment: 3.9 years [range: 4–6.2]) were included (response rate: 55%). Participation limitations were reported in 53% and were associated with impairments in functioning (15–67%) (P ≤ .01) and fatigue (P ≤ .03). Parent- and child-reported fatigue was increased compared to normative values (P ≤ .02). History of hydrocephalus was associated with increased fatigue (P ≤ .04). Younger age at diagnosis and longer time since diagnosis were associated with impairments in functioning and cognitive fatigue (P < .05). Participation limitations, impairments in functioning and fatigue were similar in PBTS who were <3 or ≥3 years since completion of treatment. More than half of PBTS reported limited participation ability, which is associated with impairments in functioning and fatigue. The complication hydrocephalus seems to lead to more fatigue. Participation limitations, impairments in functioning and fatigue appear not to diminish in the longer term.

Although bone fragility may already be present at diagnosis of pediatric acute lymphoblastic leukemia (ALL), routine performance of dual-energy X-ray absorptiometry (DXA) in every child is not universally feasible. The aim of this study was to develop and validate a risk prediction model for low lumbar spine bone mineral density (LS BMD Z-score ≤ −2.0) at diagnosis, as an important indicator for fracture risk and further treatment-related BMD aggravation. Children with ALL (4–18 years), treated according to the Dutch Childhood Oncology Group protocol (DCOG-ALL9; model development; n = 249) and children from the Canadian Steroid-Associated Osteoporosis in the Pediatric Population cohort (STOPP; validation; n = 99) were included in this study. Multivariable logistic regression analyses were used to develop the prediction model and to confirm the association of low LS BMD at diagnosis with symptomatic fractures during and shortly after cessation of ALL treatment. The area under the receiver operating characteristic curve (AUC) was used to assess model performance. The prediction model for low LS BMD at diagnosis using weight (β = −0.70) and age (β = −0.10) at diagnosis revealed an AUC of 0.71 (95% CI, 0.63–0.78) in DCOG-ALL9 and 0.74 (95% CI, 0.63–0.84) in STOPP, and resulted in correct identification of 71% of the patients with low LS BMD. We confirmed that low LS BMD at diagnosis is associated with LS BMD at treatment cessation (OR 5.9; 95% CI, 3.2–10.9) and with symptomatic fractures (OR 1.7; 95% CI, 1.3–2.4) that occurred between diagnosis and 12 months following treatment cessation. In meta-analysis, LS BMD at diagnosis (OR 1.6; 95% CI, 1.1–2.4) and the 6-month cumulative glucocorticoid dose (OR 1.9; 95% CI, 1.1–3.2) were associated with fractures that occurred in the first year of treatment. In summary, a prediction model for identifying pediatric ALL patients with low LS BMD at diagnosis, as an important indicator for bone fragility, was successfully developed and validated. This can facilitate identification of future bone fragility in individual pediatric ALL patients. © 2021 American Society for Bone and Mineral Research (ASBMR).

Background: During treatment for pediatric acute lymphoblastic leukemia (ALL), children receive high doses of dexamethasone for its apoptotic effect on leukemia cells; however, muscle atrophy is a well-known serious side effect. Muscle atrophy (loss of muscle mass) accompanied by a decreased muscle strength may lead to a generalized impaired skeletal muscle state called sarcopenia. Loss of muscle mass is also an indicator of physical frailty, which is defined as a state of increased vulnerability that is characterized by co-occurrence of low muscle mass, muscle weakness, fatigue, slow walking speed, and low physical activity. Both sarcopenia and physical frailty are related to an increased risk of infections, hospitalizations, and decreased survival in children with chronic diseases. Objective: This study aims to (1) estimate the occurrence of sarcopenia and physical frailty in children during ALL maintenance therapy, (2) evaluate the effect of administering dexamethasone, and (3) explore determinants associated with these outcomes. Methods: This prospective study is being pursued within the framework of the DexaDays-2 study: a randomized controlled trial on neurobehavioral side effects in pediatric patients with ALL. A total of 105 children (3-18 years) undergoing ALL maintenance treatment at the Princess Máxima Center for Pediatric Oncology are included in this study. Sarcopenia/frailty assessments are performed before and just after a 5-day dexamethasone course. A subset of 50 children participating in the DexaDays-2 trial because of severe dexamethasone-induced neurobehavioral problems were assessed at 3 additional timepoints. The sarcopenia/frailty assessment consists of bioimpedance analysis (skeletal muscle mass [SMM]), handheld dynamometry (handgrip strength), Pediatric Quality of Life Inventory Multidimensional Fatigue Scale (fatigue), Timed Up and Go Test (TUG; walking speed), and physical activity questionnaires. To evaluate potential change in sarcopenia/frailty components after a 5-day dexamethasone administration, a paired Student t test or Mann-Whitney U test will be used. Because of the presence of repeated measurements, generalized linear mixed models will be used to estimate the effect of dexamethasone on sarcopenia and frailty outcomes. Multivariable regression models will be estimated to investigate associations between the assessment scores and patient and treatment-related factors. Results: Patient accrual started in 2018 and was finalized in spring 2021. From autumn 2021 onward final data analyses will be performed. Conclusions: This first study combining parameters of sarcopenia and physical frailty is of importance because these conditions can seriously complicate continuation of ALL therapy, independence in physical functioning, reaching motor milestones, and participating in daily life activities. The results will provide knowledge about these complications, the association between dexamethasone treatment and muscle loss and other components of frailty, and therefore insights into the severity of this side effect. By exploring potential determinants that may be associated with sarcopenia and physical frailty, we may be able to identify children at risk at an earlier stage and provide timely interventions. International Registered Report Identifier (IRRID): DERR1-10.2196/33517

Background: During treatment for acute lymphoblastic leukaemia (ALL), children are prone to musculoskeletal deterioration. However, non‐invasive tools to measure muscle mass and intramuscular alterations are limited. In this study we explored the feasibility of muscle ultrasound in children with ALL. Additionally, we analysed whether automated ultrasound outcomes of muscle size and intramuscular fat infiltration (IMAT) were associated with appendicular skeletal muscle mass (ASMM), muscle strength and physical performance.Methods: Children with ALL, aged 3–18 years were included during maintenance therapy. Bilateral images of the rectus femoris muscle were captured using a portable linear array transducer connected to a tablet. Subsequently, an automated image annotation software (MuscleSound) was used to estimate cross‐sectional area, muscle thickness and IMAT. Feasibility was assessed using acceptance (percentage of children approached who were enrolled), practicality (percentage of children that completed the ultrasound measurement after enrolment) and implementation (percentage of children that had sufficient imaging to be processed and analysed by the software). Assessments of ASMM by bioimpedance analysis, muscle strength using handheld dynamometry and timed physical performance tests were administered at the same visit. Multivariable linear models were estimated to study the associations between muscle ultrasound outcomes and ASMM, strength and physical performance, adjusted for sex, age, body mass index and ALL treatment week.Results: Muscle ultrasound was performed in 60 out of 73 invited patients (76.9%), of which 37 were boys (61.7%), and median age was 6.1 years (range: 3–18.8 years). The acceptance was 98.7%, practicality 77.9% and implementation was 100%. Patients who refused the examination (n = 13) were younger (median: 3.6, range: 3–11.2 years) compared with the 60 examined children (P = 0.0009). In multivariable models, cross‐sectional area was associated with ASMM (β = 0.49Z‐score, 95% confidence interval [CI]:0.3,2.4), knee‐extension strength (β = 16.9 Newton [N], 95% CI: 4.8, 28.9), walking performance (β = −0.46 s, 95% CI: −0.75, −0.18) and rising from the floor (β = −1.07 s, 95% CI: −1.71, −0.42). Muscle thickness was associated with ASMM (β = 0.14Z‐score, 95% CI: 0.04, 0.24), knee‐extension strength (β = 4.73 N, 95% CI: 0.99, 8.47), walking performance (β = −0.13 s, 95% CI: −0.22, −0.04) and rising from the floor (β = −0.28 s, 95% CI: −0.48, −0.08). IMAT was associated with knee‐extension strength (β = −6.84 N, 95% CI: −12.26, −1.41), walking performance (β = 0.2 s, 95% CI: 0.08, 0.32) and rising from the floor (β = 0.54 s, 95% CI: 0.27, 0.8). None of the muscle ultrasound outcomes was associated with handgrip strength.Conclusions: Portable muscle ultrasound appears a feasible and useful tool to measure muscle size and intramuscular alterations in children with ALL. Validation studies using magnetic resonance imaging (gold standard) are necessary to confirm accuracy in paediatric populations.