A multicenter retrospective study of chemotherapy for recurrent intracranial ependymal tumors in adults by the Gruppo Italiano Cooperativo di Neuro-Oncologia

The Role of Radiotherapy, Chemotherapy, and Targeted Therapies in Adult Intramedullary Spinal Cord Tumors

Intramedullary primary spinal cord tumors are rare in adults and their classification has recently evolved. Their treatment most frequently relies on maximal safe surgical resection. Herein, we review, in light of the WHO 2021 classification of central nervous system tumors, the knowledge regarding the role of radiotherapy and systemic treatments in spinal ependymomas, spinal astrocytomas (pilocytic astrocytoma, diffuse astrocytoma, spinal glioblastoma IDH wildtype, diffuse midline glioma H3-K27M altered, and high-grade astrocytoma with piloid features), neuro-glial tumors (ganglioglioma and diffuse leptomeningeal glioneuronal tumor), and hemangioblastomas. In spinal ependymomas, radiotherapy is recommended for incompletely resected grade 2 tumors, grade 3 tumors, and recurrent tumors not amenable to re-surgery. Chemotherapy is used in recurrent cases. In spinal astrocytomas, radiotherapy is recommended for incompletely resected grade 2 astrocytomas and grade 3 or 4 tumors as well as recurrent tumors. Chemotherapy is indicated for newly diagnosed high-grade astrocytomas and recurrent cases. In hemangioblastomas not amenable to surgery, radiotherapy is an effective alternative option. Targeted therapies are playing an increasingly important role in the management of some intramedullary primary spinal cord tumor subtypes. BRAF and/or MEK inhibitors have demonstrated efficacy in pilocytic astrocytomas and glioneuronal tumors, belzutifan in von Hippel-Lindau-related hemangioblastomas, and promising results have been reported with ONC201 in diffuse midline glioma H3-K27M altered.

Treatment of Extraneural Metastases of Myxopapillary Ependymomas With Dose-Dense Temozolomide and Lapatinib

Myxopapillary ependymomas (MPEs) are rare tumors of the central nervous system, and outcomes are generally worse with recurrent disease. These tumors can rarely metastasize outside the neuraxis. We present a case of a 35-year-old female with a history of MPEs who developed extraneural metastases 11 years after her initial gross total resection. Sites of metastases included multiple bilateral intrapulmonary and pleural-based masses with pleural effusion and a pelvic mass. The patient was treated with dose-dense TMZ and lapatinib and had a mixed radiographic response after 12 cycles of treatment. This is the first known case of extraneural metastases of MPEs to demonstrate a radiographic response to dose-dense TMZ and lapatinib. This case presentation discusses the need to establish optimal treatment of extraneural ependymal metastases, duration of treatment, and strategy for the management of recurrent diseases.

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.

Survival After Resection of Newly-Diagnosed Intracranial Grade II Ependymomas: An Initial Multicenter Analysis and the Logistics of Intraoperative Magnetic Resonance Imaging

OBJECTIVE

To identify factors, including the use of intraoperative magnetic resonance imaging (iMRI), impacting overall survival (OS) and progression-free survival (PFS) after resections of newly diagnosed intracranial grade II ependymomas performed across 4 different institutions.

METHODS

Analyses of a multicenter mixed retrospective/prospective database assessed the impact of patient, treatment, and tumor characteristics on OS and PFS. iMRI workflow and logistics were also outlined.

RESULTS

Forty-three patients were identified (mean age 25.4 years, mean follow-up 52.8 months). The mean OS was 52.8 ± 44.7 months. Univariate analyses failed to identify prognostic factors associated with OS, likely due to relatively shorter follow-up time for this less aggressive glioma subtype. The mean PFS was 43.7 ± 39.8 months. Multivariate analyses demonstrated that gross-total resection was associated with prolonged PFS compared to both subtotal resection (STR) (P = 0.005) and near-total resection (P = 0.01). Infratentorial location was associated with improved PFS compared to supratentorial location (P = 0.04). Log-rank analyses of Kaplan-Meier survival curves showed that increasing extent of resection (EOR) led to improved OS specifically for supratentorial tumors (P = 0.02) and improved PFS for all tumors (P < 0.001). Thirty cases (69.8%) utilized iMRI, of which 12 (27.9%) involved additional resection after iMRI. Of these, 8/12 (66.7%) resulted in gross-total resection, while 2/12 (16.7%) were near-total resection and 2/12 (16.7%) were subtotal resection. iMRI was not an independent prognosticator of PFS (P = 0.72).

CONCLUSIONS

Greater EOR and infratentorial location were associated with increased PFS for grade II ependymomas. Greater EOR was associated with longer OS only for supratentorial tumors. A longer follow-up is needed to establish prognostic factors for this cohort, including use of iMRI.

Ependymoma: Evaluation and Management Updates

PURPOSE OF REVIEW

To review state of art and relevant advances in the molecular genetics and management of ependymomas of children and adults.

RECENT FINDINGS

Ependymomas may occur either in the brain or in the spinal cord. Compared with intracranial ependymomas, spinal ependymomas are less frequent and exhibit a better prognosis. The new WHO classification of CNS tumors of 2021 has subdivided ependymomas into different histomolecular subgroups with different outcome. The majority of studies have shown a major impact of extent of resection; thus, a complete resection must be performed, whenever possible, at first surgery or at reoperation. Conformal radiotherapy is recommended for grade 3 or incompletely resected grade II tumors. Proton therapy is increasingly employed especially in children to reduce the risk of neurocognitive and endocrine sequelae. Craniospinal irradiation is reserved for metastatic disease. Chemotherapy is not useful as primary treatment and is commonly employed as salvage treatment for patients failing surgery and radiotherapy. Standard treatments are still the mainstay of treatment: the discovery of new druggable pathways will hopefully increase the therapeutic armamentarium in the near future.

Molecular Classification and Therapeutic Targets in Ependymoma

Ependymoma is a biologically diverse tumor wherein molecular classification has superseded traditional histological grading based on its superior ability to characterize behavior, prognosis, and possible targeted therapies. The current, updated molecular classification of ependymoma consists of ten distinct subgroups spread evenly among the spinal, infratentorial, and supratentorial compartments, each with its own distinct clinical and molecular characteristics. In this review, the history, histopathology, standard of care, prognosis, oncogenic drivers, and hypothesized molecular targets for all subgroups of ependymoma are explored. This review emphasizes that despite the varied behavior of the ependymoma subgroups, it remains clear that research must be performed to further elucidate molecular targets for these tumors. Although not all ependymoma subgroups are oncologically aggressive, development of targeted therapies is essential, particularly for cases where surgical resection is not an option without causing significant morbidity. The development of molecular therapies must rely on building upon our current understanding of ependymoma oncogenesis, as well as cultivating transfer of knowledge based on malignancies with similar genomic alterations.

An Overview of Intracranial Ependymomas in Adults

Simple Summary

Ependymomas are neuroepithelial tumors arising from the central nervous system. They can form anywhere along the neuraxis. In adults, these tumors predominantly occur in the spine. Local therapy with surgery and radiotherapy represents the most effective treatment while systemic chemotherapy should be used in recurrent cases. However, in recent years, a deeper knowledge of molecular mechanisms of these tumors has been made, allowing for new potential systemic treatments. Here, we review these treatment approaches and provide an overview on the molecular characteristics of ependymomas.

Abstract

Ependymomas are rare primary central nervous system tumors. They can form anywhere along the neuraxis, but in adults, these tumors predominantly occur in the spine and less frequently intracranially. Ependymal tumors represent a heterogenous group of gliomas, and the WHO 2016 classification is based essentially on a grading system, with ependymomas classified as grade I, II (classic), or III (anaplastic). In adults, surgery is the primary initial treatment, while radiotherapy is employed as an adjuvant treatment in some cases of grade II and in all cases of anaplastic ependymoma; chemotherapy is reserved for recurrent cases. In recent years, important and interesting advances in the molecular characterization of ependymomas have been made, allowing for the identification of nine molecular subgroups of ependymal tumors and moving toward subgroup-specific patients with improved risk stratification for treatment-decisions and future prospective trials. New targeted agents or immunotherapies for ependymoma patients are being explored for recurrent disease. This review summarizes recent molecular advances in the diagnosis and treatment of intracranial ependymomas including surgery, radiation therapy and systemic therapies.

A phase II study of dose-dense temozolomide and lapatinib for recurrent low-grade and anaplastic supratentorial, infratentorial, and spinal cord ependymoma

BACKGROUND

No standard medical treatment exists for adult patients with recurrent ependymoma, and prospective clinical trials in this population have not succeeded because of its rarity and challenges in accruing patients. The Collaborative Ependymoma Research Network conducted a prospective phase II clinical trial of dose-dense temozolomide (TMZ) and lapatinib, targeting the unmethylated O6-methylguanine-DNA methyltransferase (MGMT) promoter status and increased expression of ErbB2 (human epidermal growth factor receptor 2) and ErbB1 (epidermal growth factor receptor) in ependymomas.

METHODS

Patients age 18 or older with histologically proven and progressive ependymoma or anaplastic ependymoma were eligible and received dose-dense TMZ and daily lapatinib. The primary outcome measure was median progression-free survival (PFS). Landmark 6- and 12-month PFS and objective response were measured. Serial assessments of symptom burden using the MD Anderson Symptom Inventory Brain Tumor (MDASI-BT)/MDASI-Spine Tumor modules were collected.

RESULTS

The 50 patients enrolled had a median age of 43.5 years, median Karnofsky performance status of 90, and a median of 2 prior relapses. Twenty patients had grade III, 16 grade II, and 8 grade I ependymoma. Half had spinal cord tumors; 15 had a supratentorial tumor, 8 infratentorial, and 2 had disseminated disease. Treatment was well tolerated. The median PFS was 7.8 months (95% CI: 5.5,12.2); the 6- and 12-month PFS rates were 55% and 38%, with 2 complete and 6 partial responses. Measures of symptom burden showed reduction in moderate-severe pain and other disease-related symptoms in most patients.

CONCLUSIONS

This treatment, with demonstrated clinical activity with objective responses and prolonged disease control associated with disease-related symptom improvements, is an option as a salvage regimen for adult patients with recurrent ependymoma.

Rare Primary Central Nervous System Tumors in Adults: An Overview

Overall, tumors of primary central nervous system (CNS) are quite common in adults with an incidence rate close to 30 new cases/100,000 inhabitants per year. Significant clinical and biological advances have been accomplished in the most common adult primary CNS tumors (i.e., diffuse gliomas). However, most CNS tumor subtypes are rare with an incidence rate below the threshold defining rare disease of 6.0 new cases/100,000 inhabitants per year. Close to 150 entities of primary CNS tumors have now been identified by the novel integrated histomolecular classification published by the World Health Organization (WHO) and its updates by the c-IMPACT NOW consortium (the Consortium to Inform Molecular and Practical Approaches to CNS Tumor Taxonomy). While these entities can be better classified into smaller groups either by their histomolecular features and/or by their location, assessing their treatment by clinical trials and improving the survival of patients remain challenging. Despite these tumors are rare, research, and advances remain slower compared to diffuse gliomas for instance. In some cases (i.e., ependymoma, medulloblastoma) the understanding is high because single or few driver mutations have been defined. The European Union has launched European Reference Networks (ERNs) dedicated to support advances on the clinical side of rare diseases including rare cancers. The ERN for rare solid adult tumors is termed EURACAN. Within EURACAN, Domain 10 brings together the European patient advocacy groups (ePAGs) and physicians dedicated to improving outcomes in rare primary CNS tumors and also aims at supporting research, care and teaching in the field. In this review, we discuss the relevant biological and clinical characteristics, clinical management of patients, and research directions for the following types of rare primary CNS tumors: medulloblastoma, pineal region tumors, glioneuronal and rare glial tumors, ependymal tumors, grade III meningioma and mesenchymal tumors, primary central nervous system lymphoma, germ cell tumors, spinal cord tumors and rare pituitary tumors.

DNA inhibitors for the treatment of brain tumors

Introduction: The worldwide incidence of central nervous system (CNS) primary tumors is increasing. Most of the chemotherapeutic agents used for treating these cancer types induce DNA damage, and their activity is affected by the functional status of repair systems involved in the detection or correction of DNA lesions. Unfortunately, treatment of malignant high-grade tumors is still an unmet medical need.Areas covered: We summarize the action mechanisms of the main DNA inhibitors used for the treatment of brain tumors. In addition, studies on new agents or drug combinations investigated for this indication are reviewed, focusing our attention on clinical trials that in the last 3 years have been completed, terminated or are still recruiting patients.Expert opinion: Much still needs to be done to render aggressive CNS tumors curable or at least to transform them from lethal to chronic diseases, as it is possible for other cancer types. Drugs with improved penetration in the CNS, toxicity profile, and activity against primary and recurrent tumors are eagerly needed. Targeted agents with innovative mechanisms of action and ability to harness the cells of the tumor microenvironment against cancer cells represent a promising approach for improving the clinical outcome of CNS tumors.

Extent of re-excision, sequence/timing of salvage re-irradiation, and disease-free interval impact upon clinical outcomes in recurrent/progressive ependymoma

PURPOSE

To report clinical outcomes of salvage re-irradiation (re-RT) in recurrent/progressive ependymoma.

METHODS

Medical records of patients treated with curative-intent re-RT as multi-modality management for recurrent/progressive ependymoma were analyzed retrospectively. The linear-quadratic model was used to provide estimates of biologically effective dose (BED) of irradiation using an α/β value of 2 for late CNS toxicity for each course of irradiation and summated to derive cumulative BED without correcting for the assumed recovery.

RESULTS

A total of 55 patients (median age 10 years at index diagnosis) treated with curative-intent re-RT between 2010 and 2018 were included. Median time to first recurrence was 29 months with an inter-quartile range (IQR) of 16-64 months. Majority (n = 46, 84%) of patients underwent surgical re-excision of recurrent disease. Median interval from first course of irradiation (RT1) to second course (RT2) was 35 months (IQR = 26-66 months) with a median re-RT dose of 54 Gy in 30 fractions (range 40-60 Gy), resulting in median cumulative equivalent dose in 2 Gy fraction (EQD2) of 106.2 Gy (range 92.4-117.6 Gy). Volume of re-RT was based on location and pattern of relapse, comprising uni-focal (n = 49, 89%), multi-focal (n = 3, 5.5%), or craniospinal irradiation (CSI) in 3 (5.5%) patients respectively. Thirty-six (66%) patients received platinum-based salvage chemotherapy either before or after RT2. At a median follow up of 37 months (range 6-80 months), the Kaplan-Meier estimates of 3-year progression-free survival (PFS) and overall survival (OS) for the entire study cohort were 40% and 51% respectively. Gross total resection at recurrence; early salvage re-RT (prior to chemotherapy, if any); and longer (> 2 years) disease-free interval (DFI) were associated with better survival outcomes. Salvage re-RT was generally well tolerated with only 3 (5.5%) patients developing symptomatic radiation necrosis necessitating corticosteroids.

CONCLUSION

Extent of re-excision, sequence/timing of re-RT, and DFI impact upon outcomes in curative-intent, multi-modality salvage therapy for recurrent ependymoma.

A role for ABCB1 in prognosis, invasion and drug resistance in ependymoma

Three of the hallmarks of poor prognosis in paediatric ependymoma are drug resistance, local invasion and recurrence. We hypothesised that these hallmarks were due to the presence of a sub-population of cancer stem cells expressing the multi-drug efflux transporter ABCB1. ABCB1 gene expression was observed in 4 out of 5 paediatric ependymoma cell lines and increased in stem cell enriched neurospheres. Functional inhibition of ABCB1 using vardenafil or verapamil significantly (p ≤ 0.05–0.001) potentiated the response to three chemotherapeutic drugs (vincristine, etoposide and methotrexate). Both inhibitors were also able to significantly reduce migration (p ≤ 0.001) and invasion (p ≤ 0.001). We demonstrate that ABCB1 positive patients from an infant chemotherapy-led trial (CNS9204) had a shorter mean event free survival (EFS) (2.7 versus 8.6 years; p = 0.007 log-rank analysis) and overall survival (OS) (5.4 versus 12 years; p = 0.009 log-rank analysis). ABCB1 positivity also correlated with reduced event free survival in patients with incompletely resected tumours who received chemotherapy across CNS9204 and CNS9904 (a radiotherapy-led SIOP 1999-04 trial cohort; p = 0.03). ABCB1 is a predictive marker of chemotherapy response in ependymoma patients and vardenafil, currently used to treat paediatric pulmonary hypertension in children, could be repurposed to reduce chemoresistance, migration and invasion in paediatric ependymoma patients at non-toxic concentrations.

Treatment Decisions of World Health Organization Grade II and III Ependymomas in Molecular Era

Surgery and radiotherapy are mainstays of treatment for ependymomas (EPNs). Recent molecular subgrouping could be superior to histopathological grading for predicting the prognosis of patients with EPNs. Gross total resection is an effective treatment approach regardless of its locations or pathologic grades. Adjuvant therapeutic strategies could be decided based on molecular subgrouping with risk-stratification. Information of histologic-molecular biology is now providing clues to therapeutic insights.

EANO guidelines for the diagnosis and treatment of ependymal tumors

Ependymal tumors are rare CNS tumors and may occur at any age, but their proportion among primary brain tumors is highest in children and young adults. Thus, the level of evidence of diagnostic and therapeutic interventions is higher in the pediatric compared with the adult patient population.The diagnosis and disease staging is performed by craniospinal MRI. Tumor classification is achieved by histological and molecular diagnostic assessment of tissue specimens according to the World Health Organization (WHO) classification 2016. Surgery is the crucial initial treatment in both children and adults. In pediatric patients with intracranial ependymomas of WHO grades II or III, surgery is followed by local radiotherapy regardless of residual tumor volume. In adults, radiotherapy is employed in patients with anaplastic ependymoma WHO grade III, and in case of incomplete resection of WHO grade II ependymoma. Chemotherapy alone is reserved for young children <12 months and for adults with recurrent disease when further surgery and irradiation are no longer feasible. A gross total resection is the mainstay of treatment in spinal ependymomas, and radiotherapy is reserved for incompletely resected tumors. Nine subgroups of ependymal tumors across different anatomical compartments (supratentorial, posterior fossa, spinal) and patient ages have been identified with distinct genetic and epigenetic alterations, and with distinct outcomes. These findings may lead to more precise diagnostic and prognostic assessments, molecular subgroup-adapted therapies, and eventually new recommendations pending validation in prospective studies.

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.

Recent Advances in the Classification and Treatment of Ependymomas

OPINION STATEMENT

Ependymomas are a subgroup of ependymal glia-derived neoplasms that affect children as well as adults. Arising within any CNS compartment, symptoms at presentation can range from acute onset due to increased intracranial pressure to insidious myelopathy. The overall survival (OS) outcomes in adult patients across the subgroups is heterogeneous with subependymoma having an excellent prognosis often even in the absence of any treatment, whereas supratentorial ependymomas tend to be higher grade in nature and may have an OS of 5 years despite gross total resection and adjuvant radiation. The rarity of ependymal tumors, together still only representing 1.8% of all primary CNS tumors, has been a long-standing challenge in defining optimal treatment guidelines via prospective randomized trials. Retrospective studies have supported maximal safe resection, ideally gross total resection, as the optimal treatment with adjuvant radiation therapy proffering additional tumor control. The evidence for efficacy of chemotherapy and targeted agents in adult ependymomas is minimal. Recent investigations of the molecular, genetic, and DNA methylation profiles of ependymal tumors across all age groups and CNS compartments have identified distinct oncogenic gene products as well as nine molecular subgroups correlating with similar outcomes. The 2016 World Health Organization of Tumors of the Central Nervous System update addresses some of these findings, although their clinical significance has not yet been fully validated. There are inconsistent survival outcomes in retrospective studies for ependymomas graded as II versus III, bringing into question the validity of histologic grading which is subject to high interobserver variability in part due to inconsistent application of mitotic count parameters.

Further understanding of the pathology of glioma: implications for the clinic

INTRODUCTION

Glioma classification and grading has been historically based in morphologic appearance of tumor cells: astrocytomas, oligodendrogliomas, oligoastrocytomas and ependymomas. Recent molecular advances have transformed the field of neuro-oncology, as some molecular markers harbor diagnostic, prognostic and therapeutic implications.

AREAS COVERED

In this paper we will review the major molecular changes associated with gliomas and their implications in diagnosis, prognosis, and opportunities in therapeutics. Expert commentary: Based on current understanding, adult diffuse infiltrating gliomas can be molecularly divided into three to five major subgroups with different clinical outcomes. Pediatric gliomas harbor mutations for H3F3A, ATRX and DAXX but not IDH. Circumscribed low-grade gliomas tend to have BRAF alterations. Clinical behavior of ependymomas correlates more with location than WHO grading. Posterior fossa ependymomas tend to behave worse than their cerebral or spinal cord counterparts. However, with the posterior fossa ependymomas, two distinct subtypes have emerged molecularly.

Chemotherapy for intracranial ependymoma in adults

Background

Ependymal tumors in adults are rare, accounting for less than 4 % of primary tumors of the central nervous system in this age group. The low prevalence of intracranial ependymoma in adults limits the ability to perform clinical trials. Therefore, treatment decisions are based on small, mostly retrospective studies and the role of chemotherapy has remained unclear.

Methods

We performed a retrospective study on 17 adult patients diagnosed with intracranial World Health Organisation grade II or III ependymoma, who were treated with chemotherapy at any time during the disease course. Benefit from chemotherapy was estimated by applying Macdonald criteria. Progression-free (PFS) and overall survival (OS) were calculated from start of chemotherapy, using the Kaplan-Meier method.

Results

Eleven patients had supratentorial and 6 infratentorial tumors. Ten patients were treated with temozolomide (TMZ), 3 with procarbazine/lomustine/vincristine (PCV), 3 with platinum-based chemotherapy and 1 patient received epirubicin/ifosfamide. Response rates were as follows: TMZ 8/10 stable disease; PCV 3/3 stable disease; platinum-based chemotherapy 1/3 partial response; epirubicin/ifosfamide 1/1 complete response. PFS rates at 6, 12 and 24 months were 52.9, 35.3 and 23.5 %. OS rates at 6, 12 and 24 months were 82.4, 82.4 and 70.1 %. There was no indication for a favourable prognostic role of O⁶-methylguanyl-DNA-methyltransferase (MGMT) promoter methylation which was detected in 3/12 investigated tumors.

Conclusions

Survival outcomes in response to chemotherapy in adult intracranial ependymoma patients vary substantially, but individual patients may respond to any kind of chemotherapy. There were too few patients to compare survival data between chemotherapeutic subgroups.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2323-0) contains supplementary material, which is available to authorized users.

Biology and management of ependymomas

Ependymomas are rare primary tumors of the central nervous system in children and adults that comprise histologically similar but genetically distinct subgroups. The tumor biology is typically more associated with the site of origin rather than being age-specific. Genetically distinct subgroups have been identified by genomic studies based on locations in classic grade II and III ependymomas. They are supratentorial ependymomas with C11orf95-RELA fusion or YAP1 fusion, infratentorial ependymomas with or without a hypermethylated phenotype (CIMP), and spinal cord ependymomas. Myxopapillary ependymomas and subependymomas have different biology than ependymomas with typical WHO grade II or III histology. Surgery and radiotherapy are the mainstays of treatment, while the role of chemotherapy has not yet been established. An in-depth understanding of tumor biology, developing reliable animal models that accurately reflect tumor molecule features, and high throughput drug screening are essential for developing new therapies. Collaborative efforts between scientists, physicians, and advocacy groups will enhance the translation of laboratory findings into clinical trials. Improvements in disease control underscore the need to incorporate assessment and management of patients' symptoms to ensure that treatment advances translate into improvement in quality of life.

Treatment and survival of supratentorial and posterior fossa ependymomas in adults

Ependymoma is a rare primary brain or spinal cord tumor that arises from the ependyma, a tissue of the central nervous system. This study analyzed a large cohort of adult supratentorial and posterior fossa ependymoma tumors in order to elucidate factors associated with overall survival. We utilized the USA National Cancer Database to study adult World Health Organization grade II/III supratentorial and posterior fossa ependymoma patients treated between 1998 and 2011. Overall survival was estimated by the Kaplan-Meier method and factors associated with survival were determined using a multivariate Cox proportional hazards model. Among 1318 patients, 1055 (80.0%) had grade II and 263 (20.0%) anaplastic tumors located in the posterior fossa (64.3%) and supratentorial region (35.7%). Overall average age was 44.3years, 48.0% of patients were female, 86.5% were Caucasian, and 36.8% underwent near/gross total surgical resection. Radiotherapy was given to 662 patients (50.8%) and 75 (5.9%) received chemotherapy. Older age at diagnosis (hazard ratio [HR] 1.51, p<0.0001), high tumor grade (HR 1.82, p=0.005), and large tumor size (HR 1.66, p=0.008) were associated with poor survival. Females compared to males (HR 0.67, p=0.03) and patients with posterior fossa tumors versus supratentorial (HR 0.64, p=0.04) had a survival advantage. Our study showed that older patients, with supratentorial tumors, and high histological grade had an increased risk of mortality. A survival benefit was captured in females and patients with posterior fossa tumors. Adjuvant radiotherapy and chemotherapy did not confer a survival benefit among all patients, even after stratification by tumor grade or anatomical location.

Supratentorial hemispheric ependymomas: an analysis of 109 adults for survival and prognostic factors

OBJECTIVE Survival rates and prognostic factors for supratentorial hemispheric ependymomas have not been determined. The authors therefore designed a retrospective study to determine progression-free survival (PFS), overall survival (OS), and prognostic factors for hemispheric ependymomas. METHODS The study population consisted of 8 patients from our institution and 101 patients from the literature with disaggregated survival information (n = 109). Patient age, sex, tumor side, tumor location, extent of resection (EOR), tumor grade, postoperative chemotherapy, radiation, time to recurrence, and survival were recorded. Kaplan-Meier survival analyses and Cox proportional hazard models were completed to determine survival rates and prognostic factors. RESULTS Anaplastic histology/WHO Grade III tumors were identified in 62% of cases and correlated with older age. Three-, 5-, and 10-year PFS rates were 57%, 51%, and 42%, respectively. Three-, 5-, and 10-year OS rates were 77%, 71%, and 58%, respectively. EOR and tumor grade were identified on both Kaplan-Meier log-rank testing and univariate Cox proportional hazard models as prognostic for PFS and OS. Both EOR and tumor grade remained prognostic on multivariate analysis. Subtotal resection (STR) predicted a worse PFS (hazard ratio [HR] 4.764, p = 0.001) and OS (HR 4.216, p = 0.008). Subgroup survival analysis of patients with STR demonstrated a 5- and 10-year OS of 28% and 0%, respectively. WHO Grade III tumors also had worse PFS (HR 10.2, p = 0.004) and OS (HR 9.1, p = 0.035). Patients with WHO Grade III tumors demonstrated 5- and 10-year OS of 61% and 46%, respectively. Postoperative radiation was not prognostic for PFS or OS. CONCLUSIONS A high incidence of anaplastic histology was found in hemispheric ependymomas and was associated with older age. EOR and tumor grade were prognostic factors for PFS and OS on multivariate analysis. STR or WHO Grade III pathology, or both, predicted worse overall prognosis in patients with hemispheric ependymoma.

Temozolomide as salvage treatment for recurrent intracranial ependymomas of the adult: a retrospective study

BACKGROUND

Few data are available on temozolomide (TMZ) in ependymomas.We investigated the response, survival, and correlation with MGMT promoter methylation in a cohort of patients with adult intracranial ependymoma receiving TMZ as salvage therapy after failure of surgery and radiotherapy.

PATIENTS AND METHODS

We retrieved clinical information from the institutional database and follow-up visits, and response to TMZ on MRI was evaluated according to the MacDonald criteria.

RESULTS

Eighteen patients (median age, 42 y), with either WHO grade III (10) or grade II (8) ependymoma were evaluable. Tumor location at diagnosis was supratentorial in 11 patients and infratentorial in 7. Progression before TMZ was local in 11 patients, local and spinal in 6 patients, and spinal only in one patient. A median of 8 cycles of TMZ (1-24) was administered. Response to TMZ consisted of complete response (CR) in one (5%) patient, partial response (PR) in 3 (17%) patients, stable disease (SD) in 7 (39%) patients, and progressive disease (PD) in 7 (39%) patients. Maximum response occurred after 3, 10, 14, and 15 cycles, respectively, with neurological improvement in 2 patients. All 4 responding patients were chemotherapy naïve. Both anaplastic (2) and grade II (2) tumors responded. Median progression-free survival and overall survival were 9.69 months (95% CI, 3.22-30.98) and 30.55 months (95% CI, 12.85-52.17), respectively. MGMT methylation was available in 11 patients and was not correlated with response or outcome.

CONCLUSION

TMZ has a role in recurrent chemo-naïve adult patients with intracranial ependymoma, regardless of tumor grade and MGMT methylation. We suggest that, after failure of surgery and radiotherapy, TMZ should be considered as a possible first-line treatment for recurrent ependymoma.

Glioma

Gliomas are primary brain tumours that are thought to derive from neuroglial stem or progenitor cells. On the basis of their histological appearance, they have been traditionally classified as astrocytic, oligodendroglial or ependymal tumours and assigned WHO grades I-IV, which indicate different degrees of malignancy. Tremendous progress in genomic, transcriptomic and epigenetic profiling has resulted in new concepts of classifying and treating gliomas. Diffusely infiltrating gliomas in adults are now separated into three overarching tumour groups with distinct natural histories, responses to treatment and outcomes: isocitrate dehydrogenase (IDH)-mutant, 1p/19q co-deleted tumours with mostly oligodendroglial morphology that are associated with the best prognosis; IDH-mutant, 1p/19q non-co-deleted tumours with mostly astrocytic histology that are associated with intermediate outcome; and IDH wild-type, mostly higher WHO grade (III or IV) tumours that are associated with poor prognosis. Gliomas in children are molecularly distinct from those in adults, the majority being WHO grade I pilocytic astrocytomas characterized by circumscribed growth, favourable prognosis and frequent BRAF gene fusions or mutations. Ependymal tumours can be molecularly subdivided into distinct epigenetic subgroups according to location and prognosis. Although surgery, radiotherapy and alkylating agent chemotherapy are still the mainstay of treatment, individually tailored strategies based on tumour-intrinsic dominant signalling pathways and antigenic tumour profiles may ultimately improve outcome. For an illustrated summary of this Primer, visit: http://go.nature.com/TXY7Ri.

Spinal drop metastasis in myxopapillary ependymoma: a case report and a review of treatment options

Myxopapillary ependymoma (MPE) is a World Health Organization grade I ependymoma that is quite rare and generally thought to be benign. Possible drop metastasis from MPE has been reported three times in the literature; in each case there were cotemporaneous additional MPE lesions. We report the case of a man who had a piecemeal gross total resection of a MPE at L1-L3 followed by adjuvant external beam radiotherapy (EBRT) who presented sixteen months later with a lesion in the thecal sac consistent with drop metastasis. A subtotal resection and adjuvant EBRT were performed. The patient has been disease-free in follow-up 27 months from the second surgery. A review of the literature regarding the treatment for MPE showed that gross total resection is optimal initial management. Several retrospective studies supported the role of adjuvant radiotherapy in enhancing local control and progression-free survival. Chemotherapy has a minimal role in the management of MPE.

Cisplatin and temozolomide combination in the treatment of supratentorial anaplastic ependymoma

Anaplastic ependymomas are rare tumors in adult patients. Maximal safe resection and use of radiation therapy are standard treatment approaches in patients with anaplastic ependymoma. Recurrent anaplastic ependymomas are treated by reoperation when the tumors are surgically accessible, by radiotherapy if not previously administered and by salvage chemotherapy. However, the role of chemotherapy is still unclear. A few retrospective studies showed interesting results with platinum-based regimens, while the administration of temozolomide alone demonstrated conflicting results. We present, for the first time, the case of a patient with anaplastic ependymoma refractory to platinum-based chemotherapy and temozolomide only, but showing a prolonged reduction of the lesion after receiving combination chemotherapy with cisplatin and temozolomide. A brief review of the literature on the treatment of anaplastic ependymoma follows.

An overview of the management of adult ependymomas with emphasis on relapsed disease

Ependymomas are rare neoplasms of the central nervous system. Disease-free survival after relapse is poor and approaches to treatment in recurrent disease often palliative. This overview summarises the management of primary disease for which broad consensus exists. We also extensively review treatment options in relapsed disease for which approaches to treatment are varied due to the paucity of literature evidence. Incorporated in this overview is a survey of UK neuro-oncology units to form a snapshot of current UK practise with respect to preferred systemic therapy regimens for patients with recurrent ependymoma. The outcome reflects a preference for mainly oral-based regimens. Universal guidance is lacking in the management of non-operable irradiated recurrent ependymoma and there are worthy therapeutic avenues for further investigation, in particular the role of radical re-irradiation and also the potential of bevacizumab in advanced disease. It is hoped that advances can be achieved by multicentre collaboration in future studies to overcome the difficulties posed by achieving meaningful data in such a rare tumour with extensive natural history.

A multi-center retrospective analysis of treatment effects and quality of life in adult patients with cranial ependymomas

Long term quality of life data of adult patients harboring intracranial ependymomas have not been reported. The role of adjuvant radiation therapy in Grade II ependymomas is unclear and differs from study to study. We therefore sought to retrospectively analyze outcome and quality of life of adult patients that were operated on intracranial ependymomas at four different surgical centers in two countries. All patients were attempted to be contacted via telephone to assess quality of life (QoL) at the time of the telephone interview. The standard EORTC QoL Questionnaire C30 (EORTC QLQ-C30) and the EORTC QLQ-Brain Cancer Module (QLQ-BN20) were used. 64 adult patients with intracranial ependymomas were included in the study. The only factor that was associated with increased survival was age <55 years (p < 0.001). Supratentorial location was correlated with shorter progression free survival than infratentorial location (PFS; p = 0.048). In WHO Grade II tumors local irradiation did not lead to increased PFS (p = 0.888) or overall survival (p = 0.801). Even for incompletely resected Grade II tumors local irradiation did not lead to a benefit in PFS (p = 0.911). In a multivariate analysis of QoL, irradiated patients had significantly worse scores in the item "fatigue" (p = 0.037) than non-irradiated patients. Here we present QoL data of adult patients with intracranial ependymomas. Our data show that local radiation therapy may have long-term effects on patients' QoL. Since in the incompletely resected Grade II tumors local irradiation did not lead to a benefit in PFS in this retrospective study, prospective randomized studies are necessary. In addition to age, supratentorial tumor location is associated with a worse prognosis in adult ependymoma patients.

Current treatment options for pediatric and adult patients with ependymoma

OPINION STATEMENT

Survival rates for patients with ependymoma, a glial tumor arising from the ependymal cells lining the ventricles of the brain and spinal cord canal, have changed little during the past decade. Contemporary "standard" therapy for children and adults with ependymoma consists of maximal surgical resection followed by focal irradiation except in cases of disseminated disease. Despite refinements in radiotherapy techniques and improvements in survival for patients with gross totally resected, nonanaplastic disease, many therapeutic challenges remain, especially for patients with unresectable, macroscopic, metastatic, or anaplastic disease. Moreover, radiotherapy to the developing central nervous system, especially in patients younger than age 5 years, can have potential long-term neurocognitive and neuroendocrine sequelae. Chemotherapy has not played a role in most treatment regimens for ependymoma to date, but due to the ongoing therapeutic challenges for a subset of patients, this modality is being reinvestigated in a few ongoing studies. Early recognition of patients who will not respond to primary therapy is imperative to modify treatment regimens, such as intensification with the addition of adjuvant chemotherapy, the use of novel experimental therapies, or their combination. Refinements in patient stratification schemes that are based on a combination of clinical variables and molecular profiles also require improved knowledge of tumor biology. Several molecular alterations have been identified already, some of which may be of prognostic significance. Furthermore, disruption of molecular alterations in signaling pathways involved in the development and maintenance of ependymoma by using novel molecularly targeted therapies may improve outcomes and reduce toxicity for patients with ependymoma.

Molecular genetics of ependymoma

Brain tumors are the leading cause of cancer death in children, with ependymoma being the third most common and posing a significant clinical burden. Its mechanism of pathogenesis, reliable prognostic indicators, and effective treatments other than surgical resection have all remained elusive. Until recently, ependymoma research was hindered by the small number of tumors available for study, low resolution of cytogenetic techniques, and lack of cell lines and animal models. Ependymoma heterogeneity, which manifests as variations in tumor location, patient age, histological grade, and clinical behavior, together with the observation of a balanced genomic profile in up to 50% of cases, presents additional challenges in understanding the development and progression of this disease. Despite these difficulties, we have made significant headway in the past decade in identifying the genetic alterations and pathways involved in ependymoma tumorigenesis through collaborative efforts and the application of microarray-based genetic (copy number) and transcriptome profiling platforms. Genetic characterization of ependymoma unraveled distinct mRNA-defined subclasses and led to the identification of radial glial cells as its cell type of origin. This review summarizes our current knowledge in the molecular genetics of ependymoma and proposes future research directions necessary to further advance this field.

Genetic expression profiles of adult and pediatric ependymomas: molecular pathways, prognostic indicators, and therapeutic targets

Ependymomas are tumors that can present within either the intracranial or spinal regions. While 90% of all pediatric ependymomas are intracranial, spinal cord ependymomas are more commonly found in patients 20-40 years old. Treatment for spinal lesions has achieved local control rates up to 100% following gross total resection, while pediatric intracranial tumors have 40-60% mortality. Given the inability to effectively treat ependymomas with current standard practices, researchers have focused their efforts on evaluating chromosomal alterations, genetic expression profiles, epigenetic events, and molecular pathways. While these studies have provided critical insight into the potential mechanisms underlying ependymoma pathogenesis, understanding of the intricate interplay between the various pathways involved in tumor initiation, development, and progression will require deeper investigation. However, several potential prognostic markers and therapeutic targets have been identified, providing key areas of focus for future research. The utilization of unique genetic expression profiles based upon patient age, tumor location, tumor grade, and subtype has revealed a multitude of findings warranting further study. Inspection of various molecular pathways associated with ependymomas may establish the foundation for developing novel therapies capable of achieving significant clinical improvements with individualized regimens specifically designed for personalized treatment strategies.

Stabilization of metastatic myxopapillary ependymoma with sorafenib

We report on a 59-year old woman with three huge intrathoracal masses that were accidentally diagnosed when she consulted a physician for upper abdominal discomfort. A biopsy revealed that they were metastases of a coccygeal myxopapillary ependymoma, resected 20 years before. As neither resection, debulking, nor radiation therapy were considered to be indicated, systemic therapy with temozolomide was started. At the first evaluation after four months, the metastases had progressed. Imatinib delayed the progression, but had to be stopped after six months because of critical increased pleural effusion. Using the multikinase inhibitor sorafenib, the disease was stabilized and an acceptable quality of life could be obtained for one year.

[Ependymomas of the lateral ventricle. A series of 27 cases with review of the literature]

Twenty-seven cases of ependymoma were collected in the French multicentric study dedicated to lateral ventricle tumors. The mean age of patients was 31,5 years. All patients underwent surgery, with complete resection of the tumor in 76% of cases. Histologic examination disclosed 23 grade 2 ependymomas and four grade 3 ependymomas. Postoperative mortality was 7%. Four patients underwent radiotherapy, and five chemotherapy. Local recurrence of the tumor occurred in seven cases, with a mean delay of 48 months. Disseminated disease within the central nervous system was found in only one patient. Median survival in all the 27 patients was 181 months, and median progression-free survival was 106 months. The relevant series of the literature are reviewed in order to precise the prognostic factors of ependymomas and therapeutic strategies.

[Intracranial ependymomas: retrospective study of 16 cases]

PURPOSE

To report the epidemiological, clinical aspects and therapeutic results of intracranial ependymomas in Morocco.

PATIENTS AND METHODS

Our retrospective study concerned 16 cases of intracranial ependymomas, treated from January 1995 to December 2002 at the radiotherapy department of Ibn Rochd Hospital of Casablanca, Morocco.

RESULTS

The average age was 15 years and complete surgery was possible in two cases. All the patients received cranial radiotherapy, combined with chemotherapy in six cases. Overall survival and progression-free survival at 5 years were respectively 50% and 31%. Eleven patients had local recurrence after an average period of 21 months. Progression-free survival at 5 years was better if complete resection: 100% vs. 28.6% in cases of incomplete resection, and depending on the histological type with 50% for classic ependymomas and 16.6% for anaplastic.

CONCLUSION

Ependymomas are rare tumors and complete resection is the standard treatment followed by postoperative radiotherapy. The place of chemotherapy remains to be defined.

Ependymomas in adults

Ependymomas are rare primary central nervous system tumors in adults. They occur most commonly in the spinal cord, where histopathologic evaluation is critical to differentiate the grade I myxopapillary ependymoma from the grade II ependymoma or grade III anaplastic ependymoma. Brain ependymomas are either grade II or III. Treatment for all grades and types includes maximum surgical resection. For myxopapillary ependymoma, complete removal while maintaining capsule integrity may be curative. Some grade II ependymomas may be observed carefully after imaging confirms complete resection, but grade III tumors require adjuvant radiation treatment. Radiation commonly is given to the region of tumor, except in cases in which there is imaging or cerebrospinal fluid evidence of tumor dissemination. Chemotherapy has not been studied extensively, although most reports suggest only modest benefit. Ongoing laboratory studies have uncovered important signal transduction pathways that may be better therapeutic targets, leading to the development of clinical trials using targeted agents.

Recurrent pituitary ependymoma: a complex clinical problem

Ependymomas rarely arise from the region of the pituitary fossa, with only four cases previously reported in the literature. We present a complex case of a recurrent ependymoma of the parasellar region which has been difficult to clinically manage due to its tendency to recurrence. Our patient has had four operations over the last 28 years, with external beam radiotherapy, but still has residual tumor and is currently panhypopituitary and with significant visual loss. We believe there is considerable uncertainty as to the optimal management of any future progression, which seems likely, and are currently considering the use of radiosurgery with careful sparing of the optic chiasm, or possibly the chemotherapeutic agent temozolomide. Our case emphasises the recurrent nature of this rare but difficult tumor.

Bevacizumab for recurrent ependymoma

BACKGROUND

Ependymoma is a rare type of glioma, representing 5% of all CNS malignancies. Radiotherapy (RT) is commonly administered, but there is no standard chemotherapy. At recurrence, ependymoma is notoriously refractory to therapy and the prognosis is poor. In recurrent glioblastoma, encouraging responses with bevacizumab have been observed.

METHODS

In this Institutional Review Board-approved study, we retrospectively analyzed the records of 8 adult patients treated for recurrent ependymoma and anaplastic ependymoma with bevacizumab containing chemotherapy regimens. We determined radiographic response (Macdonald criteria), median time to progression (TTP), and median overall survival (OS; Kaplan-Meier method).

RESULTS

There were 4 men and 4 women with a median age of 40 years (range, 20-65). Prior treatment included surgery (n = 8), RT (8), temozolomide (5), and carboplatin (4). Bevacizumab (5-15 mg/kg every 2-3 weeks) was administered alone (2) or concurrently with cytotoxic chemotherapy including irinotecan (3), carboplatin (2), or temozolomide (1). Six patients achieved a partial response (75%) and 1 remained stable for over 8 months. Median TTP was 6.4 months (95% confidence interval 1.4-7.4) and median OS was 9.4 months (95% confidence interval 7.0-not reached), with a median follow-up of 5.2 months among 5 surviving patients (63%).

CONCLUSIONS

The radiographic response rate to bevacizumab-containing regimens is high. A prospective study is warranted.

Temozolomide for recurrent intracranial supratentorial platinum-refractory ependymoma

BACKGROUND

To the authors' knowledge, there currently is no standard therapy for platinum-resistant ependymoma; hence, a need exists for new therapies. In the current study, a retrospective evaluation of temozolomide (TMZ) in adults with recurrent, supratentorial, platinum-refractory, World Health Organization grade 2 ependymoma was performed, with an objective of determining 6-month progression-free survival (PFS).

METHODS

A total of 25 patients, ages 28 to 63 years, with recurrent ependymoma were treated. All patients had previously been treated with surgery, radiotherapy, and platinum-based chemotherapy (cisplatin in 15 patients and carboplatin in 10 patients). Nine patients underwent repeat surgery. Patients were treated at the time of second recurrence with TMZ (5 consecutive days), once every 4 weeks, which was defined as a single cycle. Neurologic evaluation was performed every 4 weeks and neuroradiographic assessment every 8 weeks.

RESULTS

A total of 68 cycles of TMZ (median, 2 cycles; range, 1-6 cycles) was administered. TMZ-related toxicity included leukopenia (7 patients; 1 with grade 3 [grade was determine according to National Cancer Institute Common Toxicity Criteria [version 3.0]), constipation (6 patients; none with grade 3), fatigue (5 patients; none with grade 3), anemia (2; none with grade 3), thrombocytopenia (2; none with grade 3), and deep vein thrombosis (2; none with grade 3). One patient (4%) demonstrated a partial radiographic response, 9 (36%) had stable disease, and 15 (60%) developed progressive disease after 2 cycles of TMZ. Time to tumor progression ranged from 1 to 7 months (median, 2 months). Survival ranged from 2 to 8 months (median, 3 months). The 6-month and 12-month PFS were 2% and 0%, respectively.

CONCLUSIONS

TMZ in this dose schedule demonstrated little efficacy in a cohort of adults with recurrent, intracranial, platinum-refractory ependymoma.

Salvage chemotherapy for metastatic and recurrent ependymoma of childhood

INTRODUCTION

Chemotherapy has limited role in the up-front management of ependymoma. At the time of recurrence, the role of chemotherapy is also ill defined and the choice of chemotherapeutic agents is often arbitrary, based on anecdotal data and personal experience.

METHODS

The purpose of this review is to describe and critically analyze the published literature on chemotherapy in patients with recurrent and metastatic ependymoma.

DISCUSSION

The disappointing response rate with single agents (12.9%) and combinations (17.4%) emphasizes the need to re-evaluate the current chemotherapeutic approach of intracranial ependymoma, and biological studies are needed to identify targets that may be considered for clinical trials.

The genetic and epigenetic basis of ependymoma

INTRODUCTION

Although ependymoma is the third most common pediatric brain tumor, we know little about the genetic/epigenetic basis of its initiation, maintenance, or progression. This is due in part to the heterogeneity of the disease, as well as the small sample size of the cohorts analyzed in most studies.

METHODS

Many of the genetic aberrations identified to date are large genomic regions, making the differentiation between passenger and driver genes difficult. The finding of a balanced karyotype in a significant subset of pediatric posterior fossa ependymomas increases the difficulty of identifying targets for rationale therapy.

CONCLUSION

The paucity of in vitro and in vivo model systems for ependymoma compound the difficulties outlined above. In this review, we discuss the published literature on ependymoma genetics and epigenetics and discuss possible future directions for the field.

Intracranial ependymoma: factors affecting outcome

Ependymomas account for 2-9% of all neuroepithelial tumors, amounting to 6-12% of all intracranial tumors in children and up to 30% of those in children younger than 3 years. Recent findings provide evidence that intracranial and spinal ependymomas share similar molecular profiles with the radial glia of their corresponding locations. The management of intracranial ependymoma is still not optimal. The 5-year progression-free survival for children with ependymoma ranges between 30 and 50% with a worse prognosis for patients with residual disease after surgery. The prognostic relevance of most factors are still being debated. Recent studies, in which the current WHO classification criteria were applied, reported the relationship between histological grade and outcome. Biomolecular studies have identified that gain of 1q25 and EGFR overexpression correlate to poor prognosis, whereas low expression of nucleolin correlated with a favorable outcome. Ependymomas have been considered a 'surgical disease', where completeness of excision can be reached in approximately half of the cases. At present the standard treatment is radiation therapy for all patients after gross-total or near-total resection. For high-risk patients, with residual tumor, an interesting, although experimental, approach could be chemotherapy followed by secondary surgery and postoperative conformal irradiation.

Ependymomas of the adult: molecular biology and treatment

PURPOSE OF REVIEW

To review state of art and relevant advances in the molecular biology and management of ependymomas of the adult.

RECENT FINDINGS

Ependymomas of the adult are uncommon neoplasms of the central nervous system, and may occur either in the brain or the spinal cord. Compared with intracranial ependymomas, spinal ependymomas are less frequent and exhibit a better prognosis. Studies performed on genetic changes in ependymoma provide some insight into the pathogenesis and prognostic markers and yield new therapeutic targets, particularly focused on signal transduction modulators. The majority of studies have shown a major impact of extent of resection; thus, a complete resection must be performed, whenever possible, at first surgery or at reoperation. Involved field radiotherapy is recommended for anaplastic or incompletely resected grade II tumors. Craniospinal irradiation is reserved for metastatic disease. Chemotherapy is not advocated as primary treatment, and is best utilized as salvage treatment for patients failing surgery and radiotherapy.

SUMMARY

Owing to the rarity of the disease, the literature regarding ependymomas in adults is scarce and limited to retrospective series. Thus, the level of evidence regarding therapeutic strategies is low and universally accepted guidelines are lacking. Molecular biology studies suggest some potential new therapeutic targets.

O6-Methylguanine-DNA-methyltransferase in recurring anaplastic ependymomas: PCR and immunohistochemistry

Ependymomas are the third most common brain tumor in children. The post surgical management is controversial. There are no convincing data on an effective role for chemotherapy. O(6)-Methylguanine-DNA-Methyltransferase (MGMT) is a DNA repair protein considered to be a chemosensitivity predictor. Hypermethylation of the MGMT gene promoter is an important cause of MGMT inactivation. We evaluated the MGMT gene promoter methylation and the immunohistochemical MGMT protein expression in 12 recurrent anaplastic ependymomas affecting children. Our purpose was to investigate the molecular rationale of the administration of alkylating agents to children affected by recurrent anaplastic ependymomas. All ependymomas lacked MGMT promoter hypermethylation and 9 (75%) showed high MGMT protein expression (>50% tumoral cells). Differences between different recurrences in the same patient were not observed. These results may indicate MGMT as a factor of chemoresistance to alkylating drugs in anaplastic ependymomas and support the uncertainties regarding the actual benefit of chemotherapy for patients with anaplastic ependymomas.

[Chemotherapy for brain tumors in adult patients]

Chemotherapy has become a third major treatment option for patients with brain tumors, in addition to surgery and radiotherapy. The role of chemotherapy in the treatment of gliomas is no longer limited to recurrent disease. Temozolomide has become the standard of care in newly diagnosed glioblastoma. Several ongoing trials seek to define the role of chemotherapy in the primary care of other gliomas. Some of these studies are no longer only based on histological diagnoses, but take into consideration molecular markers such as MGMT promoter methylation and loss of genetic material on chromosomal arms 1p and 19q. Outside such clinical trials chemotherapy is used in addition to radiotherapy, e.g., in anaplastic astrocytoma, medulloblastoma or germ cell tumors, or as an alternative to radiotherapy, e.g., in anaplastic oligodendroglial tumors or low-grade gliomas. In contrast, there is no established role for chemotherapy in other tumors such as ependymomas, meningiomas or neurinomas. Primary cerebral lymphomas are probably the only brain tumors which can be cured by chemotherapy alone and only by chemotherapy. The chemotherapy of brain metastases follows the recommendations for the respective primary tumors. Further, strategies of combined radiochemotherapy using mainly temozolomide or topotecan are currently explored. Leptomeningeal metastases are treated by radiotherapy or systemic or intrathecal chemotherapy depending on their pattern of growth.