Systematic Review: Sleep Disorders Based on Objective Data in Children and Adolescents Treated for a Brain Tumor.

Background: Tumors of the central nervous system (CNS) are the most common solid childhood malignancy. Over the last decades, treatment developments have strongly contributed to the improved overall 5-year survival rate, which is now approaching 75%. However, children now face significant long-term morbidity with late-effects including sleep disorders that may have detrimental impact on everyday functioning and quality of life. The aims of this study were to (1) describe the symptoms that lead to polysomnographic evaluation; (2) describe the nature of sleep disorders diagnosed in survivors of childhood CNS tumor using polysomnography (PSG); and (3) explore the association between tumor location and diagnosed sleep disorder. Methods: An extensive literature search following the Preferred Reporting Items for Systematic Review and Meta-Analysis guidelines (PRISMA) was conducted. Inclusion criteria were children and adolescents diagnosed with a CNS tumor age <20 years having a PSG performed after end of tumor treatment. The primary outcome was sleep disorder confirmed by PSG. Results: Of the 1,658 studies identified, 11 met the inclusion criteria. All the included articles were appraised for quality and included in the analysis. Analyses indicated that sleep disorders commonly occur among childhood CNS tumor survivors. Symptoms prior to referral for PSG were excessive daytime sleepiness (EDS), fatigue, irregular breathing during sleep and snoring. The most common sleep disorders diagnosed were sleep-related breathing disorders (i.e., obstructive sleep apnea) and central disorders of hypersomnolence (i.e., narcolepsy). Conclusion: Our findings point to the potential benefit of systematically registering sleep disorder symptoms among CNS tumor patients together with tumor type and treatment information, so that at-risk patients can be identified early. Moreover, future rigorous and larger scale controlled observational studies that include possible modifiable confounders of sleep disorders such as fatigue and obesity are warranted. Clinical Trial Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021243866, identifier [CRD42021243866].

Asparaginase enzyme activity levels and toxicity in childhood acute lymphoblastic leukemia: a NOPHO ALL2008 study.

Asparaginase treatment is a mainstay in contemporary treatment of acute lymphoblastic leukemia (ALL), but substantial asparaginase-related toxicity may lead to jeopardized protocol compliance and compromises survival. We investigated the association between risk of asparaginase-associated toxicities (AspTox) and asparaginase enzyme activity (AEA) levels in 1155 children aged 1.0 to 17.9 years, diagnosed with ALL between July 2008 and March 2016, and treated according to the Nordic Society of Pediatric Hematology and Oncology (NOPHO) ALL2008 protocol. Patients with ≥2 blood samples for AEA measurement drawn 14 ± 2 days after asparaginase administration were included (6944 trough values). AEA was measurable (or >0 IU/L) in 955 patients, whereas 200 patients (17.3%) had asparaginase inactivation and few AspTox recorded. A time-dependent multiple Cox model of time to any first asparaginase-associated toxicity adjusted for sex and age was used. For patients with measurable AEA, we found a hazard ratio (HR) of 1.17 per 100 IU/L increase in median AEA (95% confidence interval [CI], 0.98-1.41; P = .09). For pancreatitis, thromboembolism, and osteonecrosis, the HRs were 1.40 (95% CI, 1.12-1.75; P = .002), 0.99 (95% CI, 0.70-1.40; P = .96), and 1.36 (95% CI, 1.04-1.77; P = .02) per 100 IU/L increase in median AEA, respectively. No significant decrease in the risk of leukemic relapse was found: HR 0.88 per 100 IU/L increase in AEA (95% CI, 0.66-1.16; P = .35). In conclusion, these results emphasize that overall AspTox and relapse are not associated with AEA levels, yet the risk of pancreatitis and osteonecrosis increases with increasing AEA levels.

Incidence and survival of childhood central nervous system tumors in Denmark, 1997-2019.

BACKGROUND: Incidence rates in Denmark of central nervous system (CNS) tumors remain among the highest in the world. Survival rates, however, have improved in the past decades in high-income countries. METHODS: We analyzed incidence and survival of childhood CNS tumors in Denmark diagnosed from 1997 to 2019 based on data from the Danish Childhood Cancer Registry and information on histological types, tumor localization, and treatment from medical records. RESULTS: From 1997 to 2019, 949 children<15 years were diagnosed with a CNS tumor. Age-standardized incidence was 42.1 (95% CI, 39.4-44.6) per million person-years and stable during this period. Age-specific incidence for children aged 0-4 years was 47.7 per million. More than one-third (n = 374, 39.4%) were treated with surgery alone. Overall survival rates 5 and 10 years after diagnosis were 77.6% (95% CI, 74.7-80.2) and 74.7% (95% CI, 71.7-77.5). Five-year overall survival improved from 73.0% (95% CI, 68.9-76.7) in 1997-2008 to 83.2% (95% CI, 79.2-86.4) in 2009-2019 (p-value < 0.0001) in children aged 0-4 years (p = 0.0006). CONCLUSION: Incidence rates are stable but remain among the highest in the world. Despite improved survival rates in recent years in younger children, some subtypes still have a poor prognosis.

Factors influencing participation rates in clinical late-effect studies of childhood cancer survivors.

To ensure external validation of a study population in clinical late-effect studies of childhood cancer, the participation rate must be high. This study investigated demographic data in Nordic late-effect studies and potential factors impacting participation rates such as cancer type, time since diagnosis, and duration of clinical examinations. We found 80 published studies originating from 16 cohorts, with median follow-up of 6.0 years (range 3-14). The overall participation rates ranged from 27% to 100%. The highest participation rates were seen in studies of survivors with solid tumors (92%) and the lowest in hematologic malignancies (67%) and central nervous system tumors (73%). The clinical examination in 10 studies (62.5%) lasted for more than 3 hours. Neither duration of the clinical examination nor time since diagnosis seemed to affect the participation rate. We encourage future studies to describe the recruitment process more thoroughly to improve understanding of the factors influencing participation rates.

PEG-asparaginase allergy in children with acute lymphoblastic leukemia in the NOPHO ALL2008 protocol.

BACKGROUND: L-Asparaginase is an effective drug in the treatment of childhood acute lymphoblastic leukemia (ALL). The use of L-asparaginase may be limited by serious adverse events of which allergy is the most frequent. The objective of this study was to describe the clinical aspects of PEG-asparaginase allergy in children treated according to the Nordic Society of Paediatric Haematology and Oncology (NOPHO) ALL2008 protocol. PROCEDURE: Children (1-17 years) enrolled in the NOPHO ALL2008 protocol between July 2008 and August 2011, who developed PEG-asparaginase allergy were identified through the NOPHO ALL2008 toxicity registry. In the NOPHO ALL2008 protocol, patients are randomized to 8 or 15 doses of intramuscular PEG-asparaginase (Oncaspar®) 1,000 IU/m(2) /dose administered at 2 or 6 weeks intervals during a total period of 30 weeks. (Clinical trials.gov no: NCT00819351). RESULTS: Of 615 evaluable patients, 79 patients developed clinical PEG-asparaginase allergy (cumulative risk; 13.2%) and discontinued PEG-asparaginase therapy for that reason. PEG-asparaginase allergy occurred after a median of two doses (75% range 2-4, max 14). In 58% of PEG-asparaginase hypersensitive patients, the clinical allergic reactions appeared within 2 hr after PEG-asparaginase administration and ranged from mild symptoms to systemic anaphylaxis. Nine patients experienced an anaphylactic reaction within 1 hr and 50 min from asparaginase administration; none were fatal. Four of 68 patients (6%) who subsequently received Erwinase therapy also reacted allergic to Erwinase. CONCLUSION: Clinical allergy to PEG-asparaginase occurred early in treatment, was in general moderate in severity, and mostly developed within 2 hr after PEG-asparaginase administration. The risk of subsequent Erwinase allergic reactions was low.