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Background: Few studies have characterized the burden of late effects among childhood ependymoma survivors. To address this gap, we examined these sequelae using real-world health services data in a population-based ependymoma survivor cohort., Methods: All individuals younger than 18 years diagnosed with an ependymoma in Ontario, Canada between 1987 and 2015 who had survived at least 5 years from their latest pediatric cancer event (index date) were matched 1:5 with population controls. Following linkage with provincial health services data, the cumulative incidences of multiple medical and functional outcomes between survivors and controls were compared., Results: Among 96 survivors, 77.1% had been irradiated and 9.4% had received cisplatin. At 10 years post-index, survivors were at significantly higher risk of all-cause mortality (7.1%, 95% confidence interval [CI]: 1.0-13.3 vs. 0.3%, 95% CI: 0.0-1.0; p = .0002), non-obstetric hospitalization (45.1%, 95% CI: 32.6-56.7 vs. 10.6%, 95% CI: 7.6-14.1; p < .0001), stroke (6.5%, 95% CI: 2.3-13.7 vs. 0%; p < .0001), severe hearing loss requiring an amplification device (7.5%, 95% CI: 2.7-15.7 vs. 0%; p < .0001), receiving homecare service (27.6%, 95% CI: 18.5-37.5 vs. 7.7%, 95% CI: 5.3-10.7; p < .0001), and submitting a disability support prescription claim (24.0%, 95% CI: 14.8-34.3 vs. 5.4%, 95% CI: 3.5-7.8; p < .0001) compared to controls., Conclusions: Pediatric ependymoma survivors are highly vulnerable to severe late sequelae, including death, stroke, severe hearing loss, and disability. Urgent efforts are needed to improve risk-stratification approaches that mitigate exposure to toxic therapies for children with lower risk disease. Interventions to prevent or decrease the risk of developing late sequelae are critical to optimizing survivor long-term health., (© 2024 The Author(s). Pediatric Blood & Cancer published by Wiley Periodicals LLC.)

Therapeutic strategies avoiding craniospinal irradiation were developed for young children with medulloblastoma to improve survival while protecting the neurocognitive outcomes of these vulnerable patients. These strategies most commonly rely on high-dose chemotherapy with stem cell rescue or conventional chemotherapy combined with intraventricular chemotherapy or conventional chemotherapy with adjuvant focal irradiation. Over the past decade, our growing understanding of the molecular landscape of medulloblastoma has transformed how we risk stratify and allocate treatment in this young age group. We present the results of the most recent approaches and clinical trials for medulloblastoma of early childhood, according to the different molecular subgroups. Overall, young children with sonic hedgehog medulloblastoma treated with intensive adjuvant chemotherapy achieve excellent survival and can safely be spared from radiotherapy. For patients with group 3 and 4 medulloblastomas, the interplay between molecular alterations and treatment intensity still needs to be further delineated. While recent clinical trials point toward more encouraging survival figure for a sizeable number of them, patients identified with very high-risk feature desperately needs innovative therapies., (© 2022 Wiley Periodicals LLC.)

Background: Low- and middle-income countries sustain the majority of pediatric cancer burden, with significantly poorer survival rates compared to high-income countries. Collaboration between institutions in low- and middle-income countries and high-income countries is one of the ways to improve cancer outcomes., Methods: Patient characteristics and effects of a pediatric neuro-oncology twinning program between the Hospital for Sick Children in Toronto, Canada and several hospitals in Karachi, Pakistan over 7 years are described in this article., Results: A total of 460 patients were included in the study. The most common primary central nervous system tumors were low-grade gliomas (26.7%), followed by medulloblastomas (18%), high-grade gliomas (15%), ependymomas (11%), and craniopharyngiomas (11.7%). Changes to the proposed management plans were made in consultation with expert physicians from the Hospital for Sick Children in Toronto, Canada. On average, 24% of the discussed cases required a change in the original management plan over the course of the twinning program. However, a decreasing trend in change in management plans was observed, from 36% during the first 3.5 years to 16% in the last 3 years. This program also led to the launch of a national pediatric neuro-oncology telemedicine program in Pakistan., Conclusions: Multidisciplinary and collaborative efforts by experts from across the world have aided in the correct diagnosis and treatment of children with brain tumors and helped establish local treatment protocols. This experience may be a model for other low- and middle-income countries that are planning on creating similar programs., (© 2022 Wiley Periodicals LLC.)

Neurofibromatosis type 1-associated plexiform neurofibromas can cause debilitating symptoms and be life threatening. Treatment options are limited, given their tendency to regrow following surgery and their propensity to transform into malignant tumours following radiation. Selumetinib is an oral selective inhibitor of RAS-mitogen-activated protein kinase (MAPK) 1 and 2, which has shown efficacy for tumour shrinkage/stabilisation and symptom improvement. We report a national case series of 19 children treated with selumetinib. All patients experienced symptom improvement or stabilisation with an acceptable toxicity profile, including those patients previously treated with trametinib. This real-world experience confirms previous trials showing significant clinical benefit for this patient population., (© 2022 Wiley Periodicals LLC.)

Central nervous system high-grade neuroepithelial tumor with MN1 alteration (CNS HGNET-MN1) is a rare recently described entity. Fourteen CNS HGNET-MN1 patients were identified using genome-wide methylation arrays/RT-PCR across seven institutions. All patients had surgery (gross total resection: 10; subtotal resection: four) as initial management followed by observation alone in three patients, followed by radiotherapy in eight patients (focal: five; craniospinal: two; CyberKnife: one) and systemic chemotherapy in three patients. Seven patients relapsed; five local and two metastatic, despite adjuvant radiotherapy, of which three died. Treatment of CNS HGNET-MN1 remains a major treatment challenge despite aggressive surgical resections and upfront radiotherapy, warranting new approaches to this rare malignancy., (© 2020 Wiley Periodicals LLC.)

Seventeen children at six institutions with neurofibromatosis type 2 (NF2)-related vestibular schwannomas received bevacizumab. Eight of the 13 patients with initial hearing loss (61%) showed objective hearing improvement within six months of treatment. No patients showed hearing deterioration during therapy; however, only two patients showed objective radiological response. Seven of eight patients had tumor progression or worsening hearing loss upon cessation of treatment. Bevacizumab was well tolerated with no patients discontinuing therapy. Bevacizumab appears to postpone hearing loss in childhood NF2-associated vestibular schwannomas, but responses are not durable, suggesting that either longer maintenance therapy or new strategies are required., (© 2020 Wiley Periodicals, Inc.)

Diffuse intrinsic pontine glioma (DIPG) is characterized by a short history of brainstem symptoms and well-known magnetic resonance imaging features with a fatal outcome. However, we report three unusual cases of brainstem tumors with an initial indolent and protracted course, which subsequently developed the classical imaging and clinical features of DIPG. Our findings support this notion that K27M is an early event in development and suggest that the emergence of additional events resulted in rapid progression after a long period of latency. Identification of such markers of aggressive behavior in the context of an indolent course is needed for better characterization and treatment management., (© 2019 Wiley Periodicals, Inc.)

Background: There are very few studies about the role of repeat irradiation (RT2) for children with recurrent supratentorial high-grade glioma (HGG). It was the aim of this study to assess the effectiveness and safety of RT2 in this population., Procedure: This was a retrospective cohort study of 40 children age 18 years and under with recurrent supratentorial HGG who had received at least one course of RT. In-field reirradiation volumes included focal or whole brain RT, with doses ranging from 30 to 54 Gy. The primary endpoint was overall survival (OS) from the first day of RT2., Results: Fourteen patients underwent RT2. The median survival of these patients was 6.5 months. Patients with ≥12 months elapsed time between RT1 and RT2 experienced longer OS than patients who had < 12 months (P = 0.009). There was no difference in OS between patients with or without germline mutations (e.g., Lynch, Li-Fraumeni, or constitutional mismatch-repair deficiency, P = 0.20). Ten patients received RT2 that overlapped with RT1 volumes for locally recurrent disease. Of this group, 80% experienced clinical benefit from in-field RT2, defined as clinical/radiologic response or stable disease. Ninety-three percent completed the prescribed course of RT2, with one patient developing grade 3 radiation necrosis four months after RT2. When compared with 26 patients who were not offered reirradiation, those selected for RT2 had improved median survival from the time of first disease progression (9.4 vs 3.8 months, P = 0.005)., Conclusions: Reirradiation for children with recurrent supratentorial HGG is a safe, effective treatment that provides short-term disease control., (© 2019 Wiley Periodicals, Inc.)

Most medulloblastoma protocols worldwide include vincristine during radiation and chemotherapy. A significant dose-limiting toxicity is peripheral neuropathy; however, there is a paucity of data to support the view that omission of vincristine does not impact survival. Herein we report two adolescent patients with Group 4 and SHH medulloblastoma, where vinblastine successfully replaced vincristine with resolution of their peripheral neuropathy. We furthermore show vinblastine is highly active in vitro and demonstrates equivalent antitumoral activity compared to vincristine. Substitution of vincristine with vinblastine in future studies should be considered for all patients with medulloblastoma, particularly those with hereditary neuropathy, severe vincristine toxicity, and adults., (© 2019 Wiley Periodicals, Inc.)

Objective: Clinical trials have failed to demonstrate a survival benefit of adjuvant chemotherapy in diffuse intrinsic pontine gliomas (DIPG). Radiation therapy (RT) is the only effective treatment thus far and reirradiation (rRT) has become an option at the time of progression. The aim of this study was to review the Canadian experience of DIPG rRT with a focus on the safety and possible efficacy of this approach., Method: We retrospectively reviewed the demographic, clinical, and RT data of patients with DIPG treated in Canada with rRT., Results: Since January 2011, we identified 16 patients with progressive DIPG who received rRT. Median time from diagnosis to progression was 10.5 months (range, 4-37 months). rRT was given focally in 14 patients at a dose ranging from 21.6 to 36 Gy. rRT was well tolerated by all children but one. All but three patients showed neurological improvement. With a median follow-up from original diagnosis of 19.2 months, all patients died, with a median time from rRT to death of 6.48 months (range, 3.83-13.26 months). When compared to a historic cohort of 46 consecutive patients, the median time from progression to death was 92 days in the non-reirradiated patients versus 218 days in the reirradiated ones (P = 0.0001)., Conclusion: In this limited experience, rRT was safe and feasible in patients with progressive DIPG, providing neurological improvement and a prolonged life span in most patients. Prospective Canadian rRT protocols are ongoing to further assess the benefit of this approach, including quality of life assessment., (© 2018 Wiley Periodicals, Inc.)

Adolescents and young adults (AYA) comprise a specific group of oncology patients with a distinct biological and epidemiological spectrum of central nervous system neoplasms. It has been well documented that they differ clinically, especially in relation to prognosis and chemotherapy tolerance; however, the underlying reasons for this are unclear. Recent advances in the genomics of both childhood and adult brain tumors have provided new explanations and insights into the previously described age-dependent heterogeneity. Herein, we summarize the current state of the AYA population in neuro-oncology, specifically how biological advances can help personalize therapy for this unique group of patients., (© 2017 Wiley Periodicals, Inc.)

Background: Medulloblastoma (MB) is the most common malignant brain tumor of childhood, with cerebrospinal fluid spread the most common site of metastasis. Currently, children diagnosed with MB and evidence of spinal metastasis are treated with an increased dose of craniospinal radiation (CSI). This report reviewed equivocal abnormalities including nerve root clumping, linear vascular enhancement, nerve root enhancement and/or other vague findings on spinal magnetic resonance imaging (MRI) to elucidate their prognostic significance and aid in risk stratification., Methods: This retrospective cohort study identified children (≥3 years) diagnosed with MB between 1988 and 2012. Children treated with upfront CSI were included, and staging spine MRI must have been done preoperatively or within 72 hr of primary tumor resection. Initial MRI of the spine was assessed by two independent reviewers blinded to outcome to evaluate for equivocal findings. Survival analysis was done to determine impact on prognosis., Results: One hundred of 157 patients were eligible for the analysis. Equivocal findings were identified in 48 (48%) patients, with MRI done preoperatively in 45 (94%) patients. Analysis by subgroup identified a higher proportion of equivocal findings in the sonic hedgehog (SHH) subgroup (P = 0.007). Five-year overall survival (OS) in children with equivocal findings compared to those with normal MRI was not different, 80 vs. 84.8% respectively, while OS in M3 patients was worse at 54.7% (P = 0.02)., Conclusion: A higher proportion of equivocal findings was identified in the SHH subgroup. This institutional retrospective review demonstrates equivocal findings are common, not associated with decreased OS and should not prompt increased dose of CSI., (© 2017 Wiley Periodicals, Inc.)

Infants with low-grade glioma (LGG) have a poor survival. BRAFV600E mutation has been identified in pediatric LGG; however, the use of BRAF inhibitors in infants has never been reported. A 2-month-old with V600E mutant hypothalamic/chiasmatic glioma progressed on chemotherapy resulting in profound visual loss, massive ascites, and diencephalic syndrome. Initiation of dabrafenib resulted in rapid and sustained disappearance of clinical symptoms and a profound sustained cytoreduction. BRAF inhibition was safely tolerated with dramatic clinicoradiological response, suggesting early targeted therapy is a viable option in infants with LGG. A re-evaluation of current management paradigms in this population is warranted to leverage the potential benefit of upfront-targeted therapies., (© 2016 Wiley Periodicals, Inc.)

Background: High-dose chemotherapy (HDC) strategies were developed to avoid unacceptable neurotoxicity associated with craniospinal irradiation in infants with embryonal brain tumors. However, the impact of molecular and pathological characterizations in such approaches and long-term outcome have not been widely described in young children., Methods: We retrospectively collected information from seven North American institutions, on young children with medulloblastoma (MB) treated with sequential HDC, as per the CCG 99703 protocol. Data collection included clinical presentation, histology, molecular subgroup, irradiation, ototoxicity, and neurocognitive evaluations., Results: The cohort included 53 patients diagnosed at a median age of 24 months (2.9-63.2). Seventeen patients (32.1%) had nodular desmoplatic MB, all belonging to the sonic Hedgehog (SHH) subgroup, as did 30% of classic MB. The 5-year progression-free survival (PFS) and overall survival (OS) was 69.6% (±6·9%) and 76.1% (±6.5%), respectively. Seventeen (32.1%) patients received irradiation (nine adjuvant radiotherapy [RT]). Patients with SHH and group 3 MB had a 5-year PFS of 86·2% (±7.4%) and 49·1% (±14%), respectively (P = 0.03). The 5-year PFS radiation free for group 3 MB was 46.4%. Patients with macroscopic metastasis (M2 and M3) had a worst survival. Fifteen (45.5%) patients had significant ototoxicity. Mean Full Scale Intellectual Quotient (FSIQ) for 24 survivors was 91.6 (range 52-119)., Conclusions: This HDC strategy led to an encouraging OS while only 20% of the patients received adjuvant RT. SHH MB, irrespective of histological subgroup, had an excellent outcome. Such intensive therapy may not be needed for this subgroup. Patients with classic histology or group 3 had an encouraging PFS of 58% and 46.4%, respectively, in the absence of adjuvant RT. The neurocognitive profile of the survivors appears to be within the normal range., Competing Interests: Disclaimers: None of the authors have conflict of interest to disclose, (© 2016 Wiley Periodicals, Inc.)

Background: Children presenting with medulloblastoma have a wide range of initial presenting symptoms. However, the influence of underlying tumor biology on the initial presentation of medulloblastoma is currently unknown. In light of the recent discovery of distinct medulloblastoma subgroups, we sought to define the initial presentation of childhood medulloblastoma in a subgroup specific manner., Procedure: We assembled a cohort of 126 medulloblastoma cases at the Hospital for Sick Children between 1994 and 2012 and determined subgroup affiliation using nanoString. Clinical details pertaining to the initial presentation were determined through a retrospective chart review., Results: The median pre-diagnostic interval across all medulloblastoma cases was 4 weeks (IQR: 4-12 weeks). Strikingly, when the pre-diagnostic interval was then determined in a subgroup specific manner, cases with WNT and Group 4 tumors showed significantly longer median pre-diagnostic intervals of 8 weeks compared to 2 weeks for SHH and 4 weeks for Group 3 (P = 0.0001). Younger age was significantly associated with a prolonged pre-diagnostic interval (P = 0.02 for all). When stratifying by subgroup the association with age was only significant in Group 4 (P = 0.04 for Group 4). Improved survival was significantly associated with a longer pre-diagnostic interval (P = 0.02), however is no longer significant when controlling for subgroup (P = 0.07)., Conclusions: The duration of the pre-diagnostic interval in childhood medulloblastoma is highly subgroup dependent, further highlighting the clinical heterogeneity and biological relevance of the four principle subgroups of medulloblastoma., (© 2014 Wiley Periodicals, Inc.)

Background: Molecular subtyping has allowed for the beginning of personalized treatment in children suffering from medulloblastoma (MB). However, resistance inevitably emerges against these therapies, particularly in the Sonic Hedgehog (SHH) subtype. We found that children with SHH subtype have the worst outcome underscoring the need to identify new therapeutic targets., Procedure: High content screening of a 129 compound library identified agents that inhibited SHH MB growth. Lead molecular target levels, p90 ribosomal S6 kinase (RSK) were characterized by immunoblotting and qRT-PCR. Comparisons were made to human neural stem cells (hNSC). Impact of inhibiting RSK with the small molecule BI-D1870 or siRNA was assessed in growth assays (monolayer, neurosphere, and soft agar). NanoString was used to detect RSK in a cohort of 66 patients with MB. To determine BI-D1870 pharmacokinetics/pharmacodynamics, 100 mg/kg was I.P. injected into mice and tissues were collected at various time points., Results: Daoy, ONS76, UW228, and UW426 MB cells were exquisitely sensitive to BI-D1870 but unresponsive to SHH inhibitors. Anti-tumor growth corresponded with inactivation of RSK in MB cells. BI-D1870 had no effect on hNSCs. Inhibiting RSK with siRNA or BI-D1870 suppressed growth, induced apoptosis, and sensitized cells to SHH agents. Notably, RSK expression is correlated with SHH patients. In mice, BI-D1870 was well-tolerated and crossed the blood-brain barrier (BBB)., Conclusions: RSK inhibitors are promising because they target RSK which is correlated with SHH patients as well as cause high levels of apoptosis to only MB cells. Importantly, BI-D1870 crosses the BBB, acting as a scaffold for development of more long-lived RSK inhibitors., (© 2013 Wiley Periodicals, Inc.)