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Background: The treatment of BRAF V600E gliomas with BRAF inhibitors (BRAFis) and MEK inhibitors (MEKis) has been increasingly integrated into clinical practice for pediatric low-grade gliomas (PLGGs) and pediatric high-grade gliomas (HGGs). However, some questions remain unanswered, such as the best time to start targeted therapy, duration of treatment, and discontinuation of therapy. Given that no clinical trial has been able to address these critical questions, we developed a Canadian Consensus statement for the treatment of BRAF V600E mutated pediatric as well as adolescent and young adult (AYA) gliomas. Methods: Canadian neuro-oncologists were invited to participate in the development of this consensus. The consensus was discussed during monthly web-based national meetings, and the algorithms were revised until a consensus was achieved. Results: A total of 26 participants were involved in the development of the algorithms. Two treatment algorithms are proposed, one for the initiation of treatment and one for the discontinuation of treatment. We suggest that most patients with BRAF V600E gliomas should be treated with BRAFis ± MEKis upfront. Discontinuation of treatment can be considered in certain circumstances, and we suggest a slow wean. Conclusions: Based on expert consensus in Canada, we developed algorithms for treatment initiation of children and AYA with BRAF V600E gliomas as well as a discontinuation algorithm. [ABSTRACT FROM AUTHOR]

Medical cannabis (MC) may offer therapeutic benefits for children with complex neurological conditions and chronic diseases. In Canada, parents, and caregivers frequently report encountering barriers when accessing MC for their children. These include negative preconceived notions about risks and benefits, challenges connecting with a knowledgeable healthcare provider (HCP), the high cost of MC products, and navigating MC product shortages. In this manuscript, we explore several of these barriers and provide recommendations to decision-makers to enable a family-centered and evidence-based approach to MC medicine and research for children. [ABSTRACT FROM AUTHOR]

Venous thromboembolism (VTE) is a well-recognized complication in pediatric cancer patients. It has been demonstrated that the incidence of VTE in pediatric patients with central nervous system (CNS) tumors is lower than that of patients with other cancers. Risk factors for developing cancer-related thrombosis are numerous and can include patient, disease, or treatment-related influences. The present study was designed to assess the VTE incidence in a pediatric oncology population, and to investigate whether intensity of treatment has similar associated with risk of VTE development in patients with and without CNS tumors. A retrospective population-based cohort study of pediatric oncology patients in Atlantic Canada was conducted. Data collected from medical records included demographics, cancer type, treatment, presence of central venous catheters (CVC), and presence of thrombosis. Treatment intensity was assessed using the intensity of treatment rating scale (ITR-3). Study period was from January 2000 to December 2017. SPSS version 24 was used for statistical analysis. Of 1262 patients with pediatric cancer, 247 (19.6%) had CNS tumors. VTE occurred in significantly fewer (n = 5, 2%) patients with CNS tumors compared with patients with non-CNS cancers (n = 79, 7.8%) (p = 0.001). The ITR-3 scores did not differ significantly between the CNS and non-CNS groups (p = 0.638). In a multivariate logistic regression analysis, ITR-3 score was associated with VTE (odds ratio [OR]: 1.48, 95% CI: 1.2–1.9), while presence of CNS tumor was protective (OR: 0.26, 95% CI: 0.1–0.6). We demonstrate that pediatric patients with CNS tumors experience a significantly lower incidence of VTE compared with patients with non-CNS cancer. An increase in the ITR-3 rating significantly increased the odds of developing VTE. • Significantly lower incidence of thrombosis among pediatric brain tumor patients • Similar treatment intensity between pediatric brain tumors and other cancers • Higher ITR-3 scores are associated with higher risk of thrombosis development. [ABSTRACT FROM AUTHOR]

Childhood and adolescent cancer survivors are disproportionately more likely to develop cardiovascular diseases from the late effects of cardiotoxic therapies (e.g., anthracycline-based chemotherapy and chest-directed radiotherapy). Currently, dexrazoxane is the only approved drug for preventing cancer treatment-related cardiac damage. While animal models highlight the beneficial effects of exercise cancer treatment-related cardiac dysfunction, few clinical studies have been conducted. Thus, the objective of this scoping review was to explore the designs and impact of exercise-based interventions for managing cancer treatment-related cardiac dysfunction in childhood and adolescent cancer survivors. Reviewers used Joanna Briggs Institute's methodology to identify relevant literature. Then, 4616 studies were screened, and three reviewers extracted relevant data from six reports. Reviewers found that exercise interventions to prevent cancer treatment-related cardiac dysfunction in childhood and adolescent cancer survivors vary regarding frequency, intensity, time, and type of exercise intervention. Further, the review suggests that exercise promotes positive effects on managing cancer treatment-related cardiac dysfunction across numerous indices of heart health. However, the few clinical studies employing exercise interventions for childhood and adolescent cancer survivors highlight the necessity for more research in this area. [ABSTRACT FROM AUTHOR]

Abstract: Background and purpose: Reports of secondary high-grade glioma (HGG) in survivors of childhood cancer are scarce. The aim of this study was to review the pattern of diagnosis, the treatment, and outcome of secondary pediatric HGG. Patients and methods: We performed a multi-center retrospective study among the 17 paediatric institutions participating in the Canadian Pediatric Brain Tumour Consortium (CPBTC). Results: We report on 18 patients (14 males, 4 females) treated in childhood for a primary cancer, who subsequently developed a HGG as a second malignancy. All patients had previously received radiation therapy +/− chemotherapy for either acute lymphoblastic leukaemia (n =9) or solid tumour (n =9). All HGG occurred within the previous radiation fields. At the last follow-up, 17 patients have died and the median survival time is 9.75 months. Conclusion: Although aggressive treatment seems to provide sustained remissions in some patients, the optimal management is still to be defined. Further documentation of such cases is necessary in order to better understand the pathogenesis, the natural history and the prevention of these tumours. [Copyright &y& Elsevier]

Background: The use of cannabis for medical purposes by pediatric patients is expanding across Canada; however, supporting evidence, federal regulations and treatment guidelines are lacking. To understand factors affecting treatment decisions in this landscape, we sought to delineate clinician perspectives, ethics priorities and values for cannabis authorization. Methods: We sampled participants purposefully through Canadian Childhood Cannabinoid Clinical Trials listservs, which include the majority of pediatric oncologists and palliative care physicians practising in Canada, among many other pediatric physicians and clinicians. Inclusion criteria were being a practising clinician in Canada, involvement in the care of children and willingness to be interviewed regardless of stance on medical cannabis. In November and December 2020, we conducted semistructured interviews focusing on principles, values and priorities, including medical, professional, regulatory, evidentiary and social considerations, for authorizing medical cannabis to children. Interviews were recorded, transcribed and analyzed by means of deductive and inductive thematic methods. Results: We conducted 18 interviews with a diverse group of clinicians representing a range of specialties within pediatric care, including neurology, palliative care, oncology, family medicine and pharmacology. The interviews yielded 4 themes and 12 subthemes related to a priori (medical, professional, regulatory, evidentiary and social themes) and emergent themes. The 4 themes of access, relationships and relational autonomy (autonomy within relationships), medically appropriate use and research priorities were grounded in principles of harm reduction. Participants described problematic authorization procedures that negatively affect patient use. Principles associated with relational autonomy were highlighted as a feature of open clinical communication. Benefits of appropriate medical uses weighed positively over risks, even in the context of potential effects on neurodevelopment. Participants expressed that more research is essential to align medical cannabis with biomedical standards. Interpretation: Clinicians reported pursuing ethical use of medical cannabis for pediatric patients and prioritizing their safety under principles of harm reduction. There is a need for evidence about neurodevelopmental risks, support for research, treatment guidelines and greater knowledge about stakeholder perspectives to alleviate burdens related to use of medical cannabis for pediatric patients in Canada. [ABSTRACT FROM AUTHOR]

[12] Requiring GMP certification for medical cannabis products could, however, result in a 2-tier regulatory system (with GPP and GMP certification required for recreational and medical cannabis products, respectively), and some producers may elect to exit the medical cannabis market. Health Canada also maintains a system for reporting adverse events associated with cannabis products on its Canada Vigilance website.[9] Licensed cannabis producers are required to report serious adverse events associated with the use of their products, but it is not mandatory for health care providers to do so. Children with chronic debilitating illness and pain are increasingly using cannabis for medical purposes, particularly when conventional treatment options have limited benefit or substantial adverse effects. [Extracted from the article]

Replication repair deficiency (RRD) leading to hypermutation is an important driving mechanism of high-grade glioma (HGG) occurring predominantly in the context of germline mutations in RRD-associated genes. Although HGG presents specific patterns of DNA methylation corresponding to oncogenic mutations, this has not been well studied in replication repair-deficient tumors. We analyzed 51 HGG arising in the background of gene mutations in RRD utilizing either 450 k or 850 k methylation arrays. These were compared with HGG not known to be from patients with RRD. RRD HGG harboring secondary mutations in glioma genes such as IDH1 and H3F3A displayed a methylation pattern corresponding to these methylation subgroups. Strikingly, RRD HGG lacking these known secondary mutations clustered together with an incompletely described group of HGG previously labeled "Wild type-C" or "Paediatric RTK 1". Independent analysis of two comparator HGG cohorts showed that other RRD/hypermutant tumors clustered within these subgroups, suggesting that undiagnosed RRD may be driving some HGG clustering in this location. RRD HGG displayed a unique CpG Island Demethylator Phenotype in contrast to the CpG Island Methylator Phenotype described in other cancers. Hypomethylation was enriched at gene promoters with prominent demethylation in genes and pathways critical to cellular survival including cell cycle, gene expression, cellular metabolism, and organization. These data suggest that methylation arrays may provide diagnostic information for the detection of RRD HGG. Furthermore, our findings highlight the unique natural selection pressures in these highly dysregulated, hypermutant cancers and provide the novel impact of hypermutation and RRD on the cancer epigenome. [ABSTRACT FROM AUTHOR]

Background: Tumors of the spinal cord are exceedingly rare in infancy and only a paucity of literature exists describing the spectrum of this disease and its management. The objectives of our study were to describe the demographic characteristics of spinal cord tumors (SCT) in children less than 3 years of age at diagnosis and to review their treatment and outcome. Methods: A national retrospective chart review was conducted on patients under the age of 3 years diagnosed with a primary tumor of the central nervous system (CNS) between 1990 and 2005 across Canada. Inclusion criteria were: age ≤3 years, histologic confirmation of the diagnosis, and residency in Canada. A centralized database was created and information regarding SCT was extracted. Results: Twenty-five of five hundred seventy-nine patients (4.3%) in the data bank had a SCT. The majority of tumors were low-grade astrocytomas (14/25). Leptomeningeal dissemination based on neuroradiologic imaging and/or cerebrospinal fluid cytology was present in five (20%) patients. The majority of patients underwent an incomplete surgical resection (52%). Most patients (64%) did not receive postoperative radiotherapy or chemotherapy. Seventy-two percent (18/25) developed recurrent/progression of disease. Overall 2- and 5-year survival for low- and high-grade malignancies was 93 ± 6.4% and 37.5 ± 17.1% respectively. Significant predictors of survival included mean duration of symptoms prior to initial diagnosis and recurrence/progression of disease. Conclusions: Relapse/progression of disease in infant SCT is frequent. Prolonged survival of low-grade tumors is possible with further therapy; however, the prognosis of high-grade malignancies remains poor. [ABSTRACT FROM AUTHOR]

Background: Choroid plexus tumors (CPT) are rare pediatric tumors. A population-based study on choroid plexus carcinoma (CPC) and choroid plexus papilloma (CPP) was carried out to describe the incidence, demographic, and outcome data and to identify potential prognostic factors. Methods: The CPT population from the Canadian databank of CNS tumor in children ≤36 months diagnosed between 1990 and 2005 was reviewed Results: Out of the 579 reported cases of CNS tumors, 37 were CPT. The annual age-adjusted incidence rate was 0.22 + 0.12 (95% CI 0.16-0.28)/100,000 children <3 years. There were 21 (56.7%) CPP and 16 (43.3.5%) CPC. Twenty patients (54%) were males. Median age at diagnosis was 7 months(range 0-30). Ten patients(62.5%) with CPC and one with CPP were metastatic at diagnosis. Twenty patients with CPP (95%) had a complete resection, whereas 6/16 CPC (37.5%) achieved a resection >90%. Fourteen CPC patients received adjuvant chemotherapy. None of the 37 patients received adjuvant radiation. At completion of survey, all CPP and five CPC were alive. Median survival time for CPC patients was 15 months (0-120). One death was related to intraoperative hemorrhage, another to chemotherapy-induced toxicity, and one to secondary AML. Age at diagnosis, degree of resection and metastatic status were not significant prognostic factors for CPC. Conclusion: By contrast to CPC, CPP have an excellent prognosis following surgery alone. Survival of CPC remains poor. However, these data may suggest adjuvant chemotherapy can alter the aggressive natural history of CPC. As with other rare CNS tumors, international collaboration is required to identify optimal therapy. [ABSTRACT FROM AUTHOR]

Purpose: To report the clinical course of adolescents with medulloblastoma, with specific emphasis on prognosis and pattern of relapse. Methods and Materials: We retrospectively studied the clinical course and outcomes of children aged 10–20 years with medulloblastoma, treated at centers throughout Canada between 1986 and 2003. To better assess time to relapse, a cohort of patients aged 3–20 years at diagnosis was generated. Results: A total of 72 adolescents were analyzed. Five-year overall survival and event-free survival rates were 78.3% ± 5.4% and 68.0% ± 6.2%, respectively. Late relapses occurred at a median of 3.0 years (range, 0.3–6.8 years). In univariate analysis, conventional risk stratification and the addition of chemotherapy to craniospinal radiation did not have prognostic significance. Female patients had improved overall survival (p = 0.007). Time to relapse increased with age in a linear fashion. After relapse, patients faired poorly regardless of treatment modality. Patients who did not receive chemotherapy initially had improved progression-free survival at relapse (p = 0.05). Conclusions: Our study suggests that adolescents with medulloblastoma might have a unique prognosis and pattern of relapse, dissimilar to those in younger children. They might benefit from different risk stratifications and prolonged follow-up. These issues should be addressed in future prospective trials. [Copyright &y& Elsevier]