A retrospective analysis of recurrent intracranial ependymoma

Outcome after treatment of pediatric supratentorial ependymoma: long-term follow-up of a single consecutive institutional series of 26 patients

BACKGROUND

Long-term outcome after surgical treatment of supratentorial ependymoma (STE) in children has not been extensively reported.

FINDINGS

We identified 26 children who underwent primary tumor resection of STE between 1953 and 2011, with at least 8 years follow-up. Ten patients (38%) had anaplastic and 16 had low grade ependymoma. Four of 15 children (26%) treated in the years 1953-1976 survived more than 5 years, but the observed 10-year survival was only 7%. One patient lived for 37 years, and second surgery for a local recurrent lesion disclosed a glioblastoma, possibly secondary to radiotherapy. In contrast, the observed 5-year survival rate for 11 children treated in the years 1992-2011 was 8/11 (73%) and observed 10- and 25-year survival rates were 70% and 66%, respectively. Eight patients were alive and tumor-free with follow-up periods of 8-27 (median 18) years, all treated after 1992. Five of these long-term survivors were 23-39 years old with full-time (n = 3) or part-time (n = 2) work. The last three patients were still children (9-12 years old): one with good function and two with major neurological deficits. The majority of patients (n = 18) received adjuvant radiotherapy and eight children no adjuvant treatment. Repeated resections for residual or recurrent tumor were necessary in 11 patients (42%), mostly due to local disease with progressive clinical symptoms. Eight patients underwent only one repeat resection, whereas three patients had two or more repeat resections within 18 years after initial surgery. Four patients were tumor-free after repeated resections at the latest follow-up, 2-13 years after last surgery.

CONCLUSION

Pediatric STE has a marked risk for local recurrence even after gross total resection and postoperative radiotherapy, but survival has increased following the introduction of modern treatment in recent years. Repeated surgery is an important part of treatment and may lead to persistent tumor control.

Sacral ependymoma presents 20 years after initial posterior fossa lesion

Posterior fossa ependymomas (PFEs) are designated histologically as low-grade neoplasms. Despite being characterised as benign, cases of metastasis have been reported only a few times with the patients concurrently diagnosed with the primary tumour. Interval drop metastasis or spontaneous second distal tumours are extremely rare and, in most cases, are diagnosed within a few months of primary tumour resection. Here, we report a patient with a grade 2 paediatric PFE exhibiting a 20-year interval to a second sacral ependymoma. The patient was initially diagnosed with a PFE at the age of 10 years and underwent tumour resection and postoperative radiotherapy. In their late 20s, the patient presented with basilar artery occlusion complicated by life-threatening epistaxis. Post-thrombolysis, the patient presented with a large sacral grade 1 myxopapillary ependymoma with cauda equina syndrome-like symptoms. Here, we present a rare case of two ependymomas with a 20-year interval in the same patient with compounding comorbidities.

Respective Roles of Surgery, Chemotherapy, and Radiation Therapy for Recurrent Pediatric and Adolescent Ependymoma: A National Multicentric Study

PURPOSE

Half of the children and adolescents treated for intracranial ependymoma experience recurrences that are not managed in a standardized manner. This study aimed to retrospectively evaluate recurrence treatments.

METHODS AND MATERIALS

We assessed overall survival (OS) and progression-free survival (PFS) after a first relapse in a population of patients from the Pediatric Ependymoma Photons Protons and Imaging study (PEPPI study) who were treated with surgery and radiation therapy in French Society of Childhood Cancer reference centers between 2000 and 2013. Data were analyzed using the Cox model as well as a landmark analysis at 4 months that accounted for the guarantee-time bias.

RESULTS

The median follow-up of the whole population of 202 patients was 105.1 months, with a 10-year OS of 68.2% and PFS of 45.5%. Among the 100 relapse cases, 68.0% were local relapses, 20.0% were metastatic, and 12.0% were combined (local and metastatic). Relapses were treated by surgery (n = 79) and/or reirradiation (n = 52) and/or chemotherapy (n = 22). The median follow-up after relapse was 77.8 months. The OS and PFS at 5 years were 43.1% and 16.2%, respectively. After surgery or radiation therapy of the first relapse, OS and PFS were more favorable, whereas treatments that included chemotherapy with or without focal treatment were associated with worse OS and PFS. In the multivariate analysis, stereotactic hypofractionated reirradiation after surgery was associated with a significantly better outcome (OS, P = .030; PFS, P = .008) and chemotherapy with a worse outcome (OS, P = .028; PFS, P = .033).

CONCLUSIONS

This analysis of relapse treatments within the PEPPI study determined that irrespective of whether the relapse was localized or metastatic, treatments that included surgery and/or reirradiation had better outcomes.

Application of Drug Testing Platforms in Circulating Tumor Cells and Validation of a Patient-Derived Xenograft Mouse Model in Patient with Primary Intracranial Ependymomas with Extraneural Metastases

Primary intracranial ependymoma is a challenging tumor to treat despite the availability of multidisciplinary therapeutic modalities, including surgical resection, radiotherapy, and adjuvant chemotherapy. After the completion of initial treatment, when resistant tumor cells recur, salvage therapy needs to be carried out with a more precise strategy. Circulating tumor cells (CTCs) have specifically been detected and validated for patients with primary or recurrent diffused glioma. The CTC drug screening platform can be used to perform a mini-invasive liquid biopsy for potential drug selection. The validation of potential drugs in a patient-derived xenograft (PDX) mouse model based on the same patient can serve as a preclinical testing platform. Here, we present the application of a drug testing model in a six-year-old girl with primary ependymoma on the posterior fossa, type A (EPN-PFA). She suffered from tumor recurrence with intracranial and spinal seeding at 2 years after her first operation and extraneural metastases in the pleura, lung, mediastinum, and distant femoral bone at 4 years after initial treatment. The CTC screening platform results showed that everolimus and entrectinib could be used to decrease CTC viability. The therapeutic efficacy of these two therapeutic agents has also been validated in a PDX mouse model from the same patient, and the results showed that these two therapeutic agents significantly decreased tumor growth. After precise drug screening and the combination of focal radiation on the femoral bone with everolimus chemotherapy, the whole-body bone scan showed significant shrinkage of the metastatic tumor on the right femoral bone. This novel approach can combine liquid biopsy, CTC drug testing platforms, and PDX model validation to achieve precision medicine in rare and challenging tumors with extraneural metastases.

Recurrent pediatric infratentorial ependymomas: a systematic review and meta-analysis on outcomes and molecular classification

OBJECTIVE

The aim of this study was to summarize the prognosis of recurrent infratentorial ependymomas based on treatment and molecular characterization.

METHODS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, the authors searched the PubMed, Scopus, Embase, and Ovid databases for studies on recurrent infratentorial ependymomas in patients younger than 25 years of age. Exclusion criteria included case series of fewer than 5 patients and studies that did not provide time-dependent survival data.

RESULTS

The authors' database search yielded 482 unique articles, of which 18 were included in the final analysis. There were 479 recurrent infratentorial pediatric ependymomas reported; 53.4% were WHO grade II and 46.6% were WHO grade III tumors. The overall mortality for recurrent infratentorial pediatric ependymomas was 49.1% (226/460). The pooled mean survival was 30.2 months after recurrence (95% CI 22.4-38.0 months). Gross-total resection (GTR) was achieved in 243 (59.0%) patients at initial presentation. The mean survival postrecurrence for those who received initial GTR was 42.3 months (95% CI 35.7-47.6 months) versus 26.0 months (95% CI 9.6-44.6 months) for those who received subtotal resection (STR) (p = 0.032). There was no difference in the mean survival between patients who received GTR (49.3 months, 95% CI 32.3-66.3 months) versus those who received STR (41.4 months, 95% CI 11.6-71.2 months) for their recurrent tumor (p = 0.610). In the studies that included molecular classification data, there were 169 (83.3%) posterior fossa group A (PFA) tumors and 34 (16.7%) posterior fossa group B (PFB) tumors, with 28 tumors harboring a 1q gain. PFA tumors demonstrated worse mean postprogression patient survival (24.7 months, 95% CI 15.3-34.0 months) compared with PFB tumors (48.0 months, 95% CI 32.8-63.2 months) (p = 0.0073). The average postrecurrence survival for patients with 1q+ tumors was 14.7 months.

CONCLUSIONS

The overall mortality rate for recurrent infratentorial ependymomas was found to be 49.1%, with a pooled mean survival of 30.2 months in the included sample population. More than 80% of recurrent infratentorial ependymomas were of the PFA molecular subtype, and both PFA tumors and those with 1q gain demonstrated worse prognosis after recurrence.

Ependymomas in Children and Adults

Ependymomas account for approximately 5% of all CNS tumors in adults and around 10% in the pediatric population. Contrary to traditional theories supporting that ependymomas arise from ependymal cells, recent studies propose radial glial cells as the cells of origin. In adults, half of the ependymomas arise in the spinal cord, whereas in the pediatric population, almost 90% of ependymomas are located intracranially. Most of the ependymomas are usually low-grade tumors except anaplastic variants and some cases of RELA-fusion-positive ependymomas, a molecular variant consisting the most recent addition to the 2016 World Health Organization (WHO) classification. Of note, the recently described molecular classification of ependymomas into nine distinct subgroups appears to be of greater clinical utility and prognostic value compared to the traditional histopathological classification, and parts of it are expected to be adopted by the WHO in the near future. Clinical manifestations depend on the location of the tumor with infratentorial ependymomas presenting with acute hydrocephalus. Gross total resection should be the goal of treatment. The prognostic factors of patients with ependymomas include age, grade, and location of the tumor, with children with intracranial, anaplastic ependymomas having the worst prognosis. In general, the 5-year overall survival of patients with ependymomas is around 60-70%.

The Role of Infection and Inflammation in the Pathogenesis of Pediatric Arterial Ischemic Stroke

Infections play an important role in the pathogenesis of acute ischemic stroke (AIS) in neonates and children. In neonates, chorioamnionitis or intrauterine inflammation has been implicated as a common risk factor for AIS. In infants and children, recent investigations demonstrated that even minor childhood infections are associated with subsequent increased risk for AIS. Post-infectious inflammatory mechanisms following infections with herpesviruses may lead to focal cerebral arteriopathy (FCA), one of the most common causes of AIS in a previously healthy child. Other agents such as parvovirus B19, dengue virus, and SARS-CoV-2 have recently been implicated as other potential triggers. Infections are compelling treatable stroke risk factors, with available therapies for both pathogens and downstream inflammatory effects. However, infections are common in childhood, while stroke is uncommon. The ongoing VIPS II (Vascular effects of Infection in Pediatric Stroke) study aims to identify the array of pathogens that may lead to childhood AIS and whether either unusual strains or unusual combinations of pathogens explain this paradox. Immune modulation with corticosteroids for FCA is another active area of research, with European and U.S. trials launching soon. The results of these new pediatric stroke studies combined with findings emerging from the larger field of immune-mediated post-infectious diseases will likely lead to new approaches to the prevention and treatment of pediatric stroke. This review highlights recent developments from both clinical and animal model research enhancing our understanding of this relationship between infection, inflammation, and stroke in neonates and children.

The Critical Role of Academic Clinical Trials in Pediatric Cancer Drug Approvals: Design, Conduct, and Fit for Purpose Data for Positive Regulatory Decisions

PURPOSE

For decades, academic clinical trials consortia have collaborated to optimize outcomes for childhood cancers through evaluating incremental improvements in conventional mutimodality treatment regimes. There are now increasing opportunities to partner with industry to test new medicines in academic-sponsored trials, but these collaborative studies rarely contribute to marketing authorizations. We addressed why this is the case and sought solutions to enable academic-sponsored trials to directly contribute to the licensing of new medicines.

METHODS

Under the auspices of the multistakeholder platform ACCELERATE, we convened a working group of representatives from clinical academia, pharmaceutical industry, European Medicines Agency, US Food and Drug Administration, and patient advocacy to define the challenges and propose recommendations to facilitate academic-sponsored trial design and conduct to be aligned to both the needs of the pharmaceutical company who own the asset and the expectations of the regulatory (licensing) authorities.

RESULTS

We identified that although academic consortia have long-standing expertise to conduct robust clinical trials, there were critical gaps in knowledge, standard procedures, and resources that hindered the trial data directly contributing to marketing authorization applications. We propose a suite of recommendations focused on (1) essential documents, (2) essential data, (3) data management, and (4) trial resources, specifically aimed at enabling academic-industry partnerships to deliver an academic-sponsored trial that meets the requirements for a marketing authorization submission. These recommendations pivot around transparency in academic-industry partnerships and early engagement with regulators.

CONCLUSION

Academic sponsors and industry partners need to prospectively recognize when the planned collaborative trial could contribute to an application to marketing authorization and plan accordingly. Transparent collaboration and knowledge sharing between the partners opens an important pathway for accelerating new treatments into clinical practice for children with cancer.

Ongoing Response in a Multiply Relapsed Metastatic Posterior Fossa Ependymoma A After Vorinostat and Concomitant Irradiation

Posterior fossa ependymomas A confer the worst prognosis among all subtypes. They demonstrate distinct epigenetic changes, which can be targeted with epigenetic modifiers like histone deacetylase inhibitors (Vorinostat). We describe a 3-year-old male diagnosed with a posterior fossa ependymoma who had a number of recurrences requiring multimodal therapy. Molecular analysis demonstrated a BCL-6 corepressor mutation, and methylation profiling matched with posterior fossa ependymomas A. He received craniospinal irradiation and focal boost with Vorinostat. Serial imaging after irradiation revealed a progressively decreasing tumor burden with nearly complete resolution of disease at 15 months. Histone deacetylase inhibitors demonstrate promise in treatment of carefully selected cases of ependymoma.

The Pediatric Precision Oncology INFORM Registry: Clinical Outcome and Benefit for Patients with Very High-Evidence Targets

INFORM is a prospective, multinational registry gathering clinical and molecular data of relapsed, progressive, or high-risk pediatric patients with cancer. This report describes long-term follow-up of 519 patients in whom molecular alterations were evaluated according to a predefined seven-scale target prioritization algorithm. Mean turnaround time from sample receipt to report was 25.4 days. The highest target priority level was observed in 42 patients (8.1%). Of these, 20 patients received matched targeted treatment with a median progression-free survival of 204 days [95% confidence interval (CI), 99-not applicable], compared with 117 days (95% CI, 106-143; P = 0.011) in all other patients. The respective molecular targets were shown to be predictive for matched treatment response and not prognostic surrogates for improved outcome. Hereditary cancer predisposition syndromes were identified in 7.5% of patients, half of which were newly identified through the study. Integrated molecular analyses resulted in a change or refinement of diagnoses in 8.2% of cases. SIGNIFICANCE: The pediatric precision oncology INFORM registry prospectively tested a target prioritization algorithm in a real-world, multinational setting and identified subgroups of patients benefiting from matched targeted treatment with improved progression-free survival, refinement of diagnosis, and identification of hereditary cancer predisposition syndromes.See related commentary by Eggermont et al., p. 2677.This article is highlighted in the In This Issue feature, p. 2659.

Outcomes after first relapse of childhood intracranial ependymoma

BACKGROUND

Ependymoma is the third most common malignant CNS tumor in children. Despite multimodal therapy, prognosis of relapsed ependymoma remains poor. Approaches to therapy for relapsed ependymoma are varied. We present a single-institution retrospective review of the outcomes after first relapse of intracranial ependymoma in children.

PROCEDURE

We performed a retrospective, IRB-approved chart review of patients with recurrent intracranial ependymoma treated at Dana-Farber/Boston Children's Cancer and Blood Disorders Center from 1990 to 2019.

RESULTS

Thirty-four patients with relapsed intracranial ependymoma were identified. At initial diagnosis, 11 patients had supratentorial disease, 22 with posterior fossa disease and one with metastatic disease. Median time-to-first relapse was 14.9 months from initial diagnosis (range 1.4-52.5). Seven patients had metastatic disease at first relapse. Gross total resection (GTR) was associated with improved 5-year progression-free survival (PFS) relative to subtotal resection (STR) and no surgery (p = .005). Localized disease at relapse was associated with improved 5-year overall survival (OS) when compared to metastatic disease (p = .02). Irradiation at first relapse seemed to delay progression but was not associated with statistically prolonged PFS or OS. Tumor location, histology, and chromosomal 1q status did not impact outcome at first relapse, although available molecular data were limited making definitive conclusions difficult. Median time-to-second relapse was 10 months (range 0.7-124). Five-year PFS and OS after first relapse were 19.9% and 45.1%, respectively. Median PFS and OS were 10.0 and 52.5 months after first relapse, respectively.

CONCLUSIONS

Relapsed intracranial ependymoma has a poor prognosis despite multimodal therapy. Novel therapeutic strategies are desperately needed for this disease.

Local and systemic therapy of recurrent ependymoma in children and adolescents: short- and long-term results of the E-HIT-REZ 2005 study

BACKGROUND

Survival in recurrent ependymomas in children and adolescents mainly depends on the extent of resection. Studies on repeated radiotherapy and chemotherapy at relapse have shown conflicting results.

METHODS

Using data from the German multi-center E-HIT-REZ-2005 study, we examined the role of local therapy and the efficacy of chemotherapy with blockwise temozolomide (TMZ) in children and adolescents with recurrent ependymomas.

RESULTS

Fifty-three patients with a median age of 6.9 years (1.25-25.4) at first recurrence and a median follow-up time of 36 months (2-115) were recruited. Gross- and near-total resection (GTR/NTR) were achieved in 34 (64.2%) patients and associated with a markedly improved 5-year overall survival (OS) of 48.7% vs. 5.3% in less than GTR/NTR. Radiotherapy showed no improvement in OS following complete resection (OS: 70 (CI: 19.9-120.1) vs. 95 (CI: 20.7-169.4) months), but an advantage was found in less than GTR/NTR (OS: 22 (CI: 12.7-31.3) vs. 7 (CI: 0-15.8) months). Following the application of TMZ, disease progression was observed in most evaluable cases (18/21). A subsequent change to oral etoposide and trofosfamide showed no improved response. PF-A EPN were most abundant in relapses (n = 27). RELA-positive EPN (n = 5) had a 5-year OS of 0%.

CONCLUSION

The extent of resection is the most important predictor of survival at relapse. Focal re-irradiation is a useful approach if complete resection cannot be achieved, but no additional benefit was seen after GTR/NTR. Longer-term disease stabilization (>6 months) mediated by TMZ occurred in a small number of cases (14.3%).

Outcome After Treatment of Spinal Ependymoma in Children and Adolescents: Long-Term Follow-up of a Single Consecutive Institutional Series of 33 Patients Treated Over Eight Decades

BACKGROUND

Long-term outcomes for pediatric patients treated for spinal ependymoma are unknown.

METHODS

We performed a retrospective analysis of outcome data from 33 children and young adults (0-22 years) who were operated on for a spinal ependymoma at our institution during the last 8 decades (1938-2019).

RESULTS

Nineteen patients are alive, with follow-up period up to 60 years. Twelve of them are tumor-free, and 7 are alive with disease. Fourteen patients are dead, 9 of them due to recurrent and/or progressive disease 1-56 years (median: 11 years) after the initial surgery. Four of the deceased patients were treated before 1948, 3 of them with excellent long-term survival for 62-66 years after the initial surgery. Tumor recurrence was observed in half of the patients, both local at the site of the primary tumor resection as well as widespread intraspinal presentations. Recurrences were observed within months but also occurred after up to 20 years after initial treatment. After the implementation of magnetic resonance imaging in 1987, details of recurrent disease became more easily demonstrated. Repeated resections were performed when the symptomatic spinal disease was in progress (n = 11). Furthermore, 2 patients have intracranial tumor manifestations, 1 of them underwent resection of a suprasellar tumor in 1991. Four deceased patients experienced aggressive extraspinal progressive disease requiring multiple surgeries, including pulmonary metastasis in 1 of them.

CONCLUSIONS

Pediatric spinal ependymomas can be treated with favorable results and functional outcome may be good even after more than half a century of follow-up. Nevertheless, unexpected and late recurrences may occur, and life-long follow-up is therefore recommended.

Bioinformatics analysis of microarray data reveals epithelial-mesenchymal-transition in pediatric ependymoma

The objectives of this study were to explore the possible mechanisms of pediatric ependymoma using bioinformatics methods and provide potential genes and signaling pathways for pediatric ependymoma study. The data of GES74195 from Gene Expression Ominibus was analyzed by R language for pediatric ependymoma study. The differentially expressed genes were explored using gene set enrichment analysis, search tool for the retrieval of interacting genes, Cytoscape as well as other mainstream bioinformatics methods. Extracellular matrix-receptors interaction pathways and focal adhesion pathway were demonstrated as the key signaling pathway for pediatric ependymoma. The potential hub genes enriched in the two signaling pathways were regarded as final hub genes for this microarray analysis. The development and progression of pediatric ependymoma were associated with epithelial-mesenchymal-transition. Various potential hub genes and potential key signaling pathways in order to further explore their values in the diagnosis and treatment of this disease in the future.

A retrospective analysis of recurrent pediatric ependymoma reveals extremely poor survival and ineffectiveness of current treatments across central nervous system locations and molecular subgroups

BACKGROUND

Relapse occurs in 50% of pediatric ependymoma cases and has poor prognosis. Few studies have investigated the clinical progress of relapsed disease, and treatment lacks a standardized approach.

METHODS AND MATERIALS

We analyzed 302 pediatric ependymoma cases. Tumor, demographic, and treatment variables were investigated for association with relapse risk, time to recurrence, and survival after relapse. DNA methylation profiling was performed for 135/302 cases, and predominant subgroups were EPN_PFA (n = 95) and EPN_RELA (n = 24). Chromosome 1q status was ascertained for 185/302 cases by fluorescent in-situ hybridization (FISH), multiplex ligation-dependent probe amplification (MLPA), and DNA methylation profiles.

RESULTS

Sixty-two percent of cases relapsed, with a median of two recurrences with no difference between posterior fossa and supratentorial locations (66% vs 55% relapse rate). One hundred seventeen (38%) cases relapsed within two years and five (2%) beyond 10 years. The late relapses were clinically heterogeneous. Tumor grade and treatment affected risk and time to relapse variably across subgroups. After relapse, surgery and irradiation delayed disease progression with a minimal impact on survival across the entire cohort. In the EPN_PFA and EPN_RELA groups, 1q gain was independently associated with relapse risk (subhazard ratio [SHR] 4.307, P = 0.027 and SHR 1.982, P = 0.010, respectively) while EPN_PFA had increased relapse risk compared with EPN_RELA (SHR = 0.394, P = 0.018).

CONCLUSIONS

Recurrent pediatric ependymoma is an aggressive disease with poor outcomes, for which current treatments are inadequate. We report that chromosome 1q gain increases relapse risk in common molecular subgroups in children but a deeper understanding of the underlying biology at relapse and novel therapeutic approaches are urgently needed.

Adult outcome after treatment of pediatric posterior fossa ependymoma: long-term follow-up of a single consecutive institutional series of 22 patients with more than 5 years of survival

OBJECTIVE

Ependymoma is the third most common posterior fossa tumor in children; however, there is a lack of long-term follow-up data on outcomes after surgical treatment of posterior fossa ependymoma (PFE) in pediatric patients. Therefore, the authors sought to investigate the long-term outcomes of children treated for PFE at their institution.

METHODS

The authors performed a retrospective analysis of outcome data from children who underwent treatment for PFE and survived for at least 5 years.

RESULTS

The authors identified 22 children (median age at the time of surgery 3 years, range 0-18 years) who underwent primary tumor resection of PFE during the period from 1945 to 2014 and who had at least 5 years of observed survival. None of these 22 patients were lost to follow-up, and they represent the long-term survivors (38%) from a total of 58 pediatric PFE patients treated. Nine (26%) of the 34 children treated during the pre-MRI era (1945-1986) were long-term survivors, while the observed 5-year survival rate in the children treated during the MRI era (1987-2014) was 13 (54%) of 24 patients. The majority of patients (n = 16) received adjuvant radiotherapy, and 4 of these received proton-beam irradiation. Six children had either no adjuvant treatment (n = 3) or only chemotherapy as adjuvant treatment (n = 3). Fourteen patients were alive at the time of this report. According to MRI findings, all of these patients were tumor free except 1 patient (age 78 years) with a known residual tumor after 65 years of event-free survival.Repeat resections for residual or recurrent tumor were performed in 9 patients, mostly for local residual disease with progressive clinical symptoms; 4 patients underwent only 1 repeated resection, whereas 5 patients each had 3 or more resections within 15 years after their initial surgery. At further follow-up, 5 of the patients who underwent a second surgery were found to be dead from the disease with or without undergoing additional resections, which were performed from 6 to 13 years after the second procedure. The other 4 patients, however, were tumor free on the latest follow-up MRI, performed from 6 to 27 years after the last resection. Hence, repeated surgery appears to increase the chance of tumor control in some patients, along with modern (proton-beam) radiotherapy. Six of 8 patients with more than 20 years of survival are in a good clinical condition, 5 of them in full-time work and 1 in part-time work.

CONCLUSIONS

Pediatric PFE occurs mostly in young children, and there is marked risk for local recurrence among 5-year survivors even after gross-total resection and postoperative radiotherapy. Repeated resections are therefore an important part of treatment and may lead to persistent tumor control. Even though the majority of children with PFE die from their tumor disease, some patients survive for more than 50 years with excellent functional outcome and working capacity.

INFORM2 NivEnt: The first trial of the INFORM2 biomarker driven phase I/II trial series: the combination of nivolumab and entinostat in children and adolescents with refractory high-risk malignancies

Background

Pediatric patients with relapsed or refractory disease represent a population with a desperate medical need. The aim of the INFORM (INdividualized Therapy FOr Relapsed Malignancies in Childhood) program is to translate next generation molecular diagnostics into a biomarker driven treatment strategy. The program consists of two major foundations: the INFORM registry providing a molecular screening platform and the INFORM2 series of biomarker driven phase I/II trials. The INFORM2 NivEnt trial aims to determine the recommended phase 2 dose (RP2D) of the combination treatment of nivolumab and entinostat (phase I) and to evaluate activity and safety (phase II).

Methods

This is an exploratory non-randomized, open-label, multinational and multicenter seamless phase I/II trial in children and adolescents with relapsed / refractory or progressive high-risk solid tumors and CNS tumors. The phase I is divided in 2 age cohorts: 12–21 years and 6–11 years and follows a 3 + 3 design with two dose levels for entinostat (2 mg/m² and 4 mg/m² once per week) and fixed dose nivolumab (3 mg/kg every 2 weeks). Patients entering the trial on RP2D can seamlessly enter phase II which consists of a biomarker defined four group basket trial: high mutational load (group A), high PD-L1 mRNA expression (group B), focal MYC(N) amplification (group C), low mutational load and low PD-L1 mRNA expression and no MYC(N) amplification (group D). A Bayesian adaptive design will be used to early stop cohorts that fail to show evidence of activity. The maximum number of patients is 128.

Discussion

This trial intends to exploit the immune enhancing effects of entinostat on nivolumab using an innovative biomarker driven approach in order to maximize the chance of detecting signs of activity. It prevents exposure to unnecessary risks by applying the Bayesian adaptive design for early stopping for futility. The adaptive biomarker driven design provides an innovative approach accelerating drug development and reducing exposure to investigational treatments in these vulnerable children at the same time.

Trial registration

ClinicalTrials.gov, NCT03838042. Registered on 12 February 2019.

Craniospinal irradiation as part of re-irradiation for children with recurrent intracranial ependymoma

BACKGROUND

The goal of this study was to evaluate outcomes in children with relapsed, molecularly characterized intracranial ependymoma treated with or without craniospinal irradiation (CSI) as part of a course of repeat radiation therapy (re-RT).

METHODS

This was a retrospective cohort study of 31 children. Patients with distant relapse received CSI as part of re-RT. For patients with locally recurrent ependymoma, those treated before 2012 were re-irradiated with focal re-RT. In 2012, institutional practice changed to offer CSI, followed by boost re-RT to the site of resected or gross disease.

RESULTS

Median follow-up was 5.5 years. Of 9 patients with distant relapse after initial RT, 2-year freedom from progression (FFP) and overall survival (OS) were 12.5% and 62.5%, respectively. There were 22 patients with local failure after initial RT. In these patients, use of CSI during re-RT was associated with improvement in 5-year FFP (83.3% with CSI vs 15.2% with focal re-RT only, P = 0.030). In the subgroup of patients with infratentorial primary disease, CSI during re-RT also improved 5-year FFP (100% with CSI, 10.0% with focal re-RT only, P = 0.036). Twenty-three patients had known molecular status; all had posterior fossa group A tumors (n = 17) or tumors with a RELA (v-rel avian reticuloendotheliosis viral oncogene homolog A) fusion (n = 6). No patient developed radiation necrosis after fractionated re-RT, though almost all survivors required assistance throughout formal schooling. Five out of 10 long-term survivors have not developed neuroendocrine deficits.

CONCLUSIONS

Re-irradiation with CSI is a safe and effective treatment for children with locally recurrent ependymoma and improves disease control compared with focal re-irradiation, with the benefit most apparent for those with infratentorial primary tumors.

A systematic review and meta-analysis of outcomes in pediatric, recurrent ependymoma

PURPOSE

The purpose of this study was to determine outcomes in recurrent pediatric ependymoma.

METHODS

We performed a systematic review of PubMed, Embase, Web of Science and the Cochrane Library for studies reporting on survival outcomes for pediatric patients with recurrent ependymoma. We then performed a meta-analysis of all eligible results. Survival outcomes were identified across location of recurrence, therapy at recurrence, and age at recurrence.

RESULTS

Eleven studies met final inclusion criteria. Pooled median progression free survival (PFS) from date of first recurrence was 6.7 months (95% confidence interval [95% CI] 4.7-8.8). Pooled median overall survival (OS) from date of first recurrence was 11.2 months (95% CI 6.4-16.0). Participants with supratentorial recurrences demonstrated a shorter OS of 8.3 months (95% CI 3.2-13.3) compared to 20.1 months (95% CI 8.4-31.7) for those with infratentorial recurrence. Patients who underwent surgery at recurrence had a median OS of 24.2 months (95% CI 14.2-34.1) compared to 29.2 months (95% CI 17.4-41.1) in those who received radiation compared to 19.3 months (95% CI 10.3-28.3) in those who received chemotherapy. Patients younger than age 3 years at time of recurrence demonstrated a median OS of 31.0 months (95% CI - 25.3-87.3) compared to 17.5 months (95% CI 9.9-25.2) for those that recurred beyond 3 years of age.

CONCLUSIONS

Our findings illustrate that children with recurrent ependymoma suffer from poor outcomes; however, these outcomes range widely depending on patient, tumor, and treatment characteristics. New therapies and treatment strategies are needed to improve outcomes in this group.

Current and Emerging Methods of Management of Ependymoma

PURPOSE OF REVIEW

This review discusses the evidence base behind current and emerging strategies of management of intracranial and spinal ependymomas in children, with a particular focus on aspects of surgical techniques, challenges and complications.

RECENT FINDINGS

The cornerstone of management remains maximal safe resective surgery, which has repeatedly been shown to correlate with improved survival. This is followed by focal conformal radiotherapy, although good results using proton beam therapy, with the potential for diminished side effects, are emerging. The role of chemotherapy remains largely unproven for paediatric ependymoma. Despite optimal management strategies, many children with ependymoma suffer from tumour recurrence. The standard of care for paediatric ependymoma comprises surgery and radiotherapy. Results of ongoing clinical trials will help shape its management in order to leverage our increasingly sophisticated understanding of the genetic drivers behind these tumours into survival benefit for this challenging group of patients.

[Radicalness and complications of repeated surgery for malignant neuroepithelial tumors of the posterior cranial fossa in children]

Treatment of primary malignant neuroepithelial tumors of the posterior cranial fossa (PCF) in childhood includes surgical resection, radiation therapy (RT), and chemotherapy (CT). The radicalness of surgery is one of the most important prognostic factors of survival. Despite the significant advances in treatment, many of these tumors recur. Today, oncologists are increasingly recommending repeated surgery for recurrent malignant neuroepithelial tumors of the PCF to achieve gross total resection (GTR). Patients undergo this surgery after RT and palliative CT, which may increase surgical risks.

OBJECTIVE

The study objective was to assess the resection extent of recurrent malignant neuroepithelial tumors of the PCF in children as well as the risk and structure of postoperative complications.

MATERIAL AND METHODS

The prospective study included 50 patients under the age of 18 who underwent surgery for recurrent malignant neuroepithelial tumors of the PCF at the Neurosurgical Institute (NSI) in the period between 2002 and June 2015. Anaplastic ependymomas were present in 37 patients, and medulloblastomas were detected in 13 patients. A total of 58 repeated surgeries were performed.

RESULTS

GTR was achieved in 53 (91.4%) cases, near total resection (NTR) was achieved in 2 (3.4%) cases, and subtotal resection (STR) was achieved in 3 (5.2%) cases. The mean bed-day after surgery was 12 (4-47) days, and the mean critical care stay was 3.2 (0-23) days. Seven patients required tracheostomy; meningitis developed in 3 patients; liquorrhea occurred in 2 cases. Ventriculoperitoneal shunting was used in 8 (13.8%) cases. One (1.7%) patient died in the early postoperative period.

CONCLUSION

Our results demonstrate that resection of recurrent malignant neuroepithelial tumors in children can be performed with high radicalness (90%) and acceptable risks.

Pediatric ependymoma: current treatment and newer therapeutic insights

Advances in genomic, transcriptomic and epigenomic profiling now identifies pediatric ependymoma as a defined biological entity. Molecular interrogation has segregated these tumors into distinct biological subtypes based on anatomical location, age and clinical outcome, which now defines the need to tailor therapy even for histologically similar tumors. These findings now provide reasons for a paradigm shift in therapy, which should profile future clinical trials focused on targeted therapeutic strategies and risk-based treatment. The need to diagnose and differentiate the aggressive variants, which include the posterior fossa group A and the supratentorial RELA fusion subtypes, is imperative to escalate therapy and improve survival.

Pediatric Brain Tumors

PURPOSE OF REVIEW

This article describes the most common pediatric brain tumors and highlights recent developments in their diagnosis and treatment strategies.

RECENT FINDINGS

We are in the midst of a molecular era for pediatric brain tumors. Genetic and epigenetic profiling of tumors has impacted their diagnosis, allowing for the subgrouping of heterogeneous tumor groups and leading to the complete renaming of some tumor types. These advances are reflected in the new 2016 World Health Organization classification. For example, primitive neuroectodermal tumors have been completely eliminated and replaced by subgroups defined by the absence or presence of specific chromosomal amplification. Medulloblastomas, diffuse astrocytomas, and ependymomas now have specific subtypes that are based on defining molecular features. More recent epigenetic-based subgrouping of atypical teratoid/rhabdoid tumors have not yet made it into the official classification system, but will surely have an impact on how these tumors are regarded in future preclinical and clinical trials.

SUMMARY

Genetic and epigenetic data are changing how pediatric brain tumors are diagnosed, are leading to new guidelines for how treatment outcome analyses can be organized, and are offering molecular targets that can be used for the development of novel therapies.

Ependymomas overexpress chemoresistance and DNA repair-related proteins

BACKGROUND

After surgery and radiation, treatment options for ependymoma are few making recurrence a challenging issue. Specifically, the efficacy of chemotherapy at recurrence is limited. We performed molecular profiling on a cohort of ependymoma cases in order to uncover therapeutic targets and to elucidate the molecular mechanisms contributing to treatment resistance.

RESULTS

This ependymoma cohort showed minimal alterations in gene amplifications and mutations but had high expression rates of DNA synthesis and repair enzymes such as RRM1 (47%), ERCC1 (48%), TOPO1 (62%) and class III β-tublin (TUBB3) (57%), which are also all associated with chemoresistance. This cohort also had high expression rates of transporter proteins that mediate multi-drug resistance including BCRP (71%) and MRP1 (43%). Subgroup analyses showed that cranial ependymomas expressed the DNA synthesis enzyme TS significantly more frequently than spinal lesions did (57% versus 15%; p = 0.0328) and that increased TS expression was correlated with increased tumor grade (p = 0.0009). High-grade lesions were also significantly associated with elevated expression of TOP2A (p = 0.0092) and TUBB3 (p = 0.0157).

MATERIALS AND METHODS

We reviewed the characteristics of 41 ependymomas (21 cranial, 20 spinal; 8 grade I, 11 grade II, 22 grade III) that underwent multiplatform profiling with immunohistochemistry, next-generation sequencing, and in situ hybridization.

CONCLUSIONS

Ependymomas are enriched with proteins involved in chemoresistance and in DNA synthesis and repair, which is consistent with the meager clinical effectiveness of conventional systemic therapy in ependymoma. Adjuvant therapies that combine conventional chemotherapy with the inhibition of chemoresistance-related proteins may represent a novel treatment paradigm for this difficult disease.

Adult Supratentorial Extraventricular Anaplastic Ependymoma: Therapeutic Approach and Clinical Review

We report a 69-year-old patient with left paresthesia and hemiparesis. Magnetic resonance imaging revealed a right frontoparietal cystic tumor. A subtotal surgical resection was performed, and an Ommaya reservoir was left in place. The pathological diagnosis was supratentorial extraventricular anaplastic ependymoma. Radiation therapy was administered, and Ommaya reservoir drainages were performed. Four months after, her clinical status deteriorated after a reservoir drainage and image revealed an acute hemorrhage. An additional resection was carried out, and chemotherapy was undergone. One month later the tumor relapsed and the patient died 18 months after initial diagnosis. Some poor prognostic factors have been suggested in the literature: Young age, incomplete tumor resection – eloquent area location, histological anaplasia, supratentorial, and extraventricular locations. Ommaya reservoirs may be used in cystic lesions as a temporary measure only. Surgery is the mainstay of therapy with adjuvant radiotherapy and/or chemotherapy.

Next-generation personalised medicine for high-risk paediatric cancer patients - The INFORM pilot study

The 'Individualized Therapy for Relapsed Malignancies in Childhood' (INFORM) precision medicine study is a nationwide German program for children with high-risk relapsed/refractory malignancies, which aims to identify therapeutic targets on an individualised basis. In a pilot phase, reported here, we developed the logistical and analytical pipelines necessary for rapid and comprehensive molecular profiling in a clinical setting. Fifty-seven patients from 20 centers were prospectively recruited. Malignancies investigated included sarcomas (n = 25), brain tumours (n = 23), and others (n = 9). Whole-exome, low-coverage whole-genome, and RNA sequencing were complemented with methylation and expression microarray analyses. Alterations were assessed for potential targetability according to a customised prioritisation algorithm and subsequently discussed in an interdisciplinary molecular tumour board. Next-generation sequencing data were generated for 52 patients, with the full analysis possible in 46 of 52. Turnaround time from sample receipt until first report averaged 28 d. Twenty-six patients (50%) harbored a potentially druggable alteration with a prioritisation score of 'intermediate' or higher (level 4 of 7). Common targets included receptor tyrosine kinases, phosphoinositide 3-kinase-mammalian target of rapamycin pathway, mitogen-activated protein kinase pathway, and cell cycle control. Ten patients received a targeted therapy based on these findings, with responses observed in some previously treatment-refractory tumours. Comparative primary relapse analysis revealed substantial tumour evolution as well as one case of unsuspected secondary malignancy, highlighting the importance of re-biopsy at relapse. This study demonstrates the feasibility of comprehensive, real-time molecular profiling for high-risk paediatric cancer patients. This extended proof-of-concept, with examples of treatment consequences, expands upon previous personalised oncology endeavors, and presents a model with considerable interest and practical relevance in the burgeoning era of personalised medicine.

Posterior fossa tumors in infants and neonates

INTRODUCTION

Management of posterior fossa tumors in infants and neonates is challenging. The characteristics of the young babies make surgery very difficult, sometimes precluding a safe complete removal.

METHODS

A review of the literature was undertaken to examine the incidence, histology, surgical aspects, and prognosis of posterior fossa tumors in the first year of life. Therapeutical strategies of the most frequent tumor types are also discussed in detail.

RESULTS

Histology is dominated by tumors with aggressive behavior, such as medulloblastomas, atypical teratoid/rhabdoid tumors, and anaplastic ependymomas. The most important surgical considerations in small children are the small circulating blood volume; the poor thermoregulation; and incomplete maturation of the brain, of the skull, and of the soft tissue. Treatment toxicity is inversely related to the age of the patients. Radiation therapy is usually considered as contraindicated in young children, with few exceptions. Proton therapy is a promising tool, but access to this kind of treatment is still limited. The therapeutic limitations of irradiation render resection of this tumor and adjuvant chemotherapy often the only therapeutic strategy in many cases.

CONCLUSIONS

The overall prognosis remains dismal because of the prevalent aggressive histologies, the surgical challenges, and the limitations of adjuvant treatment. Nevertheless, the impressive improvements in anesthesiology and surgical techniques allow, in the vast majority of the cases, complete removal of the lesions with minor sequelae in high-volume referral pediatric centers.

Low-grade ependymoma with late metastasis: autopsy case study and literature review

INTRODUCTION

Ependymoma metastasis occurs usually along with local recurrence within 7 years after the initial diagnosis. Later spinal metastasis without local recurrence after the surgical resection has been rarely reported in patients with low-grade ependymomas but not with high-grade ependymomas. Here, we present a case with autopsy revealing late extensive supratentorial metastasis of a fourth ventricle classic WHO grade II ependymoma with no local recurrence or spinal metastasis.

METHODS

A 4-year-old boy underwent a gross total resection (GTR) of the fourth ventricle ependymoma and postoperative radiation therapy. Follow-up MRI showed no recurrence for the next 7 years, but a half year later, extra-axial tumors in the left cerebellopontine angle and right frontal lobe were observed. GTR of the left cerebellopontine angle ependymoma was performed, followed by additional radiation therapy.

RESULTS

He was stable for the following 2 years before MRI revealed growth of the right frontal tumor and new lesions. GTR of the right frontal tumor demonstrated similar pathologic features of ependymoma. Despite chemotherapy, follow-up MRIs exhibited increasing numbers and sizes of supratentorial tumors but no infratentorial or spinal tumors. He died 15 years after the initial diagnosis. Postmortem brain examination confirmed the supratentorial subarachnoid dissemination with multifocal metastases of classic ependymomas but no recurrence at the infratentorial sites.

CONCLUSION

Our case study and literature review suggest that low-grade ependymomas under the current WHO classification have the risk of late metastasis. Therefore, long-term follow-up of the whole neuroaxis is more important for the patients with low-grade ependymomas even in the absence of local recurrence.