A multi-institutional phase II trial of bevacizumab for recurrent and refractory meningioma

Background

Systemic therapies for refractory meningiomas are limited with no FDA-approved therapeutics. Vascular endothelial growth factor (VEGF) is a signaling protein associated with neovascularization, peritumoral edema, and meningioma tumorigenesis.

Methods

This phase II study investigates the efficacy of bevacizumab (BEV), a VEGF binding monoclonal antibody, in patients with progressive Grade I (G1M), Grade II (G2M), Grade III (G3M) meningioma, and other non-parenchymal tumors including vestibular schwannoma (n = 4) and hemangiopericytoma (n = 4) with the primary endpoint of progression-free survival rate at 6-months (PFS-6). Non-meningiomas were included with the respective meningioma grade in the analysis. Secondary endpoints include median overall survival (mOS) and response rate.

Results

Fifty Patients (26 women; median age 54 years; range 23-81), 42 with progressive meningioma were treated: 10 G1M, 20 G2M, and 12 G3M. Prior treatments include surgical resection (41 patients), radiosurgery (24 patients), external beam radiotherapy (28 patients), and chemotherapy (14 patients). Median infusions administered were 16 (range, 2-68). Response was graded using the Macdonald's criteria. PFS-6, median PFS, and mOS were 87%, 22 months, 35 months for G1M; 77%, 23 months, 41 months for G2M; and 46%, 8 months, 12 months for G3M. Best radiographic responses include stable disease (G1M: 100%; G2M: 85%; G3M: 82%); partial response (G1M: 0%; G2M: 5%; G3M: 0%) and progressive disease (G1M: 0%; G2M: 10%; G3M:18%). The most common toxicities were hypertension (n = 19, 42.2%), proteinuria (n = 16, 35.6%), and fatigue (n = 14, 31.1%).

Conclusion

This study showed BEV is well tolerated and appears to be a promising systemic treatment option for patients with recurrent and refractory meningiomas.

Response assessment in medulloblastoma and leptomeningeal seeding tumors: recommendations from the Response Assessment in Pediatric Neuro-Oncology committee

Lack of standard response criteria in clinical trials for medulloblastoma and other seeding tumors complicates assessment of therapeutic efficacy and comparisons across studies. An international working group was established to develop consensus recommendations for response assessment. The aim is that these recommendations be prospectively evaluated in clinical trials, with the goal of achieving more reliable risk stratification and uniformity across clinical trials. Current practices and literature review were performed to identify major confounding issues and justify subsequently developed recommendations; in areas lacking scientific investigations, recommendations were based on experience of committee members and consensus was reached after discussion. Recommendations apply to both adult and pediatric patients with medulloblastoma and other seeding tumors. Response should be assessed using MR imaging (brain and spine), CSF cytology, and neurologic examination. Clinical imaging standards with minimum mandatory sequence acquisition that optimizes detection of leptomeningeal metastases are defined. We recommend central review prior to inclusion in treatment cohorts to ensure appropriate risk stratification and cohort inclusion. Consensus recommendations and response definitions for patients with medulloblastomas and other seeding tumors have been established; as with other Response Assessment in Neuro-Oncology recommendations, these need to now be prospectively validated in clinical trials.

Corticosteroid use endpoints in neuro-oncology: Response Assessment in Neuro-Oncology Working Group

Background

Corticosteroids are the mainstay of treatment for peritumor edema but are often associated with significant side effects. Therapies that can reduce corticosteroid use would potentially be of significant benefit to patients. However, currently there are no standardized endpoints evaluating corticosteroid use in neuro-oncology clinical trials.

Methods

The Response Assessment in Neuro-Oncology (RANO) Working Group has developed consensus recommendations for endpoints evaluating corticosteroid use in clinical trials in both adults and children with brain tumors.

Results

Responders are defined as patients with a 50% reduction in total daily corticosteroid dose compared with baseline or reduction of the total daily dose to ≤2 mg of dexamethasone (or equivalent dose of other corticosteroid); baseline dose must be at least 4 mg of dexamethasone daily (or equivalent dose of other corticosteroids) for at least one week. Patients must have stable or improved Neurologic Assessment in Neuro-Oncology (NANO) score or Karnofsky performance status score or Eastern Cooperative Oncology Group (ECOG) (Lansky score for children age <16 y), and an improved score on a relevant clinical outcome assessment tool. These criteria must be sustained for at least 4 weeks after baseline assessment to be considered a response, and are confirmed 4 weeks after that (ie, 8 wk after baseline assessment) to be considered a sustained response.

Conclusions

This RANO proposal for corticosteroid use endpoints in neuro-oncology clinical trials may need to be refined and will require prospective validation in clinical studies.

Cerebrospinal Fluid Dissemination and Neoplastic Meningitis in Primary Brain Tumors

BACKGROUND

Neoplastic meningitis, also known as leptomeningeal disease, affects the entire neuraxis. The clinical manifestations of the disease may affect the cranial nerves, cerebral hemispheres, or the spine. Because of the extent of disease involvement, treatment options and disease staging should involve all compartments of the cerebrospinal fluid (CSF) and subarachnoid space. Few studies of patients with primary brain tumors have specifically addressed treatment for the secondary complication of neoplastic meningitis. Therapy for neoplastic meningitis is palliative in nature and, rarely, may have a curative intent.

METHODS

A review of the medical literature pertinent to neoplastic meningitis in primary brain tumors was performed. The complication of neoplastic meningitis is described in detail for the various types of primary brain tumors.

RESULTS

Treatment of neoplastic meningitis is complicated because determining who should receive aggressive, central nervous system (CNS)-directed therapy is difficult. In general, the therapeutic response of neoplastic meningitis is a function of CSF cytology and, secondarily, of the clinical improvement in neurological manifestations related to the disease. CSF cytology may manifest a rostrocaudal disassociation; thus, consecutive, negative findings require that both lumbar and ventricular cytological testing are performed to confirm the complete response. Based on data from several prospective, randomized trials extrapolated to primary brain tumors, the median rate of survival for neoplastic meningitis is several months. Oftentimes, therapy directed at palliation may improve quality of life by protecting patients from experiencing continued neurological deterioration.

CONCLUSIONS

Neoplastic meningitis is a complicated disease in which response to therapy varies by histology. Thus, survival rates after CNS-directed therapy will differ by the underlying primary tumor. Optimal therapy of neoplastic meningitis is poorly defined, and few guidelines exist to guide clinicians on the most appropriate choice of therapy.

Patterns of recurrence in patients with sinonasal undifferentiated carcinoma (SNUC) treated with multimodality therapy at a single center

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Background: SNUCs are rare and without established therapeutic standards. This is a retrospective review of therapeutic outcomes in pts with SNUCs treated at our center. Methods: Data was collected retrospectively on pts with a confirmed diagnosis of SNUC treated at the University of Washington Medical Center. Demographic data, tumor/treatment characteristics,and dates of recurrence/progression and death were recorded. The Kaplan Meier method was used to estimate survival outcomes; the log-rank and Wilcoxon tests were used to explore associations of clinical characteristics with outcome. Results: Between 5/1992 and 11/2016, 32 pts were treated, 1 was excluded due to incomplete data. The median age was 52 (range 22-82) years, 14(45%) were female, 26(83%) were white, 17(54%) reported current or former tobacco use. One presented with distant metastases, 1 had T2N0 disease, and all other pts had locally advanced disease. Six pts had nodal involvement on initial staging, and 25 patients had T4 disease. Eleven(35%) pts had no skull base/CNS invasion, 7(22%) had skull base extension up to the cribriform plate, 13(42%) had extension beyond the cribriform plate and into the CNS. Twenty-one(67%) pts underwent surgical resection, 29(93%) underwent radiation(XRT) with a median dose of 70 (range 54-72) Gy, and 28(90%) received cisplatin based chemotherapy, with 24 of these given concurrent with XRT, 19(60%) were treated with surgery followed by chemoradiation. With a median 61 months of follow up, 15 pts have recurred, 10 of these recurrences occurred in local sites, with 6 having intracranial progression, 2 of which were leptomeningeal. The median time to progression was 15 months and median overall survival was 58 months . Any vs no tobacco use (58 vs 35 mo p = 0.8), was not predictive of overall survival. The presence of nodal disease (87 vs 7 mo p = 0.005), and CNS invasion beyond the cribriform plate (NR vs 14 mo p = 0.04) was associated with inferior median overall survival. Conclusions: Local/CNS recurrence was the predominant failure pattern in our pts. CNS invasion beyond the cribriform plate and nodal disease were associated with significantly worse survival.

Nivolumab for patients with recurrent glioblastoma progressing on bevacizumab: A retrospective case series

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Objective: A single institution retrospective evaluation of nivolumab following disease progression on bevacizumab in adults with recurrent glioblastoma (GBM) with an objective of determining progression free survival (PFS). Background: There is no accepted therapy for recurrent GBM after failure of bevacizumab. Methods: 16 adults, ages 52-72 years (median 62), with recurrent GBM were treated. All patients had previously been treated with surgery, concurrent radiotherapy and temozolomide, and post-radiotherapy temozolomide. Bevacizumab (with or without lomustine) was administered to all patients at first recurrence. Patients were treated with nivolumab only (3mg/kg) once every 2 weeks at second recurrence. One cycle of nivolumab was defined as 2 treatments. Neurological evaluation was performed bi-weekly and neuroradiographic assessment every 4 weeks. Results: A total of 37 treatment cycles (median 2) were administered of nivolumab in which there were 14 Grade 2 adverse events (AEs) and Grade 3 AEs in 2 patients. No Grade 4 or 5 AEs were seen. Following 1 month of nivolumab, 7 patients’ demonstrated progressive disease and discontinued therapy. No patient demonstrated a response though 9 patients demonstrated neuroradiographic stable response. Survival in the entire cohort ranged from 2 - 6 months with a median of 3.5 months (CI: 2.8, 4.2). Median and 6-month PFS at 6 months was 2.0 months (range 1-5 months; CI: 1.3, 2.7) and 0% respectively. Conclusions: Nivolumab salvage therapy demonstrated no survival advantage in patients with recurrent bevacizumab refractory GBM emphasizing a continued unmet need in neuro-oncology.

Nivolumab for patients with recurrent glioblastoma progressing on bevacizumab: a retrospective case series

A single institution retrospective evaluation of nivolumab following disease progression on bevacizumab in adults with recurrent glioblastoma (GBM) with an objective of determining progression free survival (PFS). There is no accepted therapy for recurrent GBM after failure of bevacizumab. 16 adults, ages 52-72 years (median 62), with recurrent GBM were treated. All patients had previously been treated with surgery, concurrent radiotherapy and temozolomide, and post-radiotherapy temozolomide. Bevacizumab (with or without lomustine) was administered to all patients at first recurrence. Patients were treated with nivolumab only (3 mg/kg) once every 2 weeks at second recurrence. One cycle of nivolumab was defined as 2 treatments. Neurological evaluation was performed bi-weekly and neuroradiographic assessment every 4 weeks. A total of 37 treatment cycles (median 2) were administered of nivolumab in which there were 14 Grade 2 adverse events (AEs) and Grade 3 AEs in two patients. No Grade 4 or 5 AEs were seen. Following 1 month of nivolumab, seven patients demonstrated progressive disease and discontinued therapy. No patient demonstrated a response though nine patients demonstrated neuroradiographic stable response. Survival in the entire cohort ranged from 2 to 6 months with a median of 3.5 months (CI 2.8, 4.2). Median and 6-month PFS at 6 months was 2.0 months (range 1-5 months; CI 1.3, 2.7) and 0% respectively. Nivolumab salvage therapy demonstrated no survival advantage in patients with recurrent bevacizumab refractory GBM emphasizing a continued unmet need in neuro-oncology.

Systemic therapy of brain metastases: non-small cell lung cancer, breast cancer, and melanoma

Brain metastases (BM) occur frequently in many cancers, particularly non-small cell lung cancer (NSCLC), breast cancer, and melanoma. The development of BM is associated with poor prognosis and has an adverse impact on survival and quality of life. Commonly used therapies for BM such as surgery or radiotherapy are associated with only modest benefits. However, recent advances in systemic therapy of many cancers have generated considerable interest in exploration of those therapies for treatment of intracranial metastases.This review discusses the epidemiology of BM from the aforementioned primary tumors and the challenges of using systemic therapies for metastatic disease located within the central nervous system. Cumulative data from several retrospective and small prospective studies suggest that molecularly targeted systemic therapies may be an effective option for the treatment of BM from NSCLC, breast cancer, and melanoma, either as monotherapy or in conjunction with other therapies. Larger prospective studies are warranted to further characterize the efficacy and safety profiles of these targeted agents for the treatment of BM.

Neuro-oncology: a selected review of ASCO 2016 abstracts

ASCO 2016, 29 May-2 June 2016, Chicago, IL, USA The largest annual clinical oncology conference the American Society of Clinical Oncology is held in the USA and gives researchers and other key opinion leaders the opportunity to present new cancer clinical trials and research data. The CNS tumors section of the American Society of Clinical Oncology 2016 covered various aspects of neuro-oncology including metastatic CNS diseases and primary brain tumors, presented via posters, oral talks and over 100 abstracts. This brief review selectively highlights presentations from this meeting in an organizational manner that reflects clinically relevant aspects of a large and multifaceted meeting.

Central Nervous System Cancers, Version 1.2015

The NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines) for Central Nervous System (CNS) Cancers provide interdisciplinary recommendations for managing adult CNS cancers. Primary and metastatic brain tumors are a heterogeneous group of neoplasms with varied outcomes and management strategies. These NCCN Guidelines Insights summarize the NCCN CNS Cancers Panel's discussion and highlight notable changes in the 2015 update. This article outlines the data and provides insight into panel decisions regarding adjuvant radiation and chemotherapy treatment options for high-risk newly diagnosed low-grade gliomas and glioblastomas. Additionally, it describes the panel's assessment of new data and the ongoing debate regarding the use of alternating electric field therapy for high-grade gliomas.

A selected review of abstracts from the 20th Annual Meeting of the Society for Neuro-Oncology (SNO)

20th Annual Meeting of the Society for Neuro-Oncology, San Antonio, TX, USA, 18-22 November 2015 The Society for Neuro-Oncology is the largest neuro-oncology meeting in the USA that meets annually and provides a multiday venue that showcases new brain cancer clinical trial results and basic research primarily pertaining to gliomas. The Society for Neuro-Oncology 2015 meeting comprising one education day, 2 days of premeetings and 3 days of presentation, over 200 oral presentations and 900 abstracts provides an overview of contemporary neuro-oncology that includes metastatic disease of the central nervous system as well as primary brain tumors. This review attempts to highlight select abstracts presented at this year's meeting in a short summary that provides a synopsis of a large and multifaceted meeting.

Current Management of Adult Diffuse Infiltrative Low Grade Gliomas

Diffuse infiltrative low grade gliomas (LGG) account for approximately 15 % of all gliomas. The prognosis of LGG differs between high-risk and low-risk patients notwithstanding varying definitions of what constitutes a high-risk patient. Maximal safe resection optimally is the initial treatment. Surgery that achieves a large volume resection improves both progression-free and overall survival. Based on results of three randomized clinical trials (RCT), radiotherapy (RT) may be deferred in patients with low-risk LGG (defined as age <40 years and having undergone a complete resection), although combined chemoradiotherapy has never been prospectively evaluated in the low-risk population. The recent RTOG 9802 RCT established a new standard of care in high-risk patients (defined as age >40 years or incomplete resection) by demonstrating a nearly twofold improvement in overall survival with the addition of PCV (procarbazine, CCNU, vincristine) chemotherapy following RT as compared to RT alone. Chemotherapy alone as a treatment of LGG may result in less toxicity than RT; however, this has only been prospectively studied once (EORTC 22033) in high-risk patients. A challenge remains to define when an aggressive treatment improves survival without impacting quality of life (QoL) or neurocognitive function and when an effective treatment can be delayed in order to preserve QoL without impacting survival. Current WHO histopathological classification is poorly predictive of outcome in patients with LGG. The integration of molecular biomarkers with histology will lead to an improved classification that more accurately reflects underlying tumor biology, prognosis, and hopefully best therapy.

Anaplastic astrocytoma

Anaplastic astrocytoma (AA) is a diffusely infiltrating, malignant, astrocytic, primary brain tumor. AA is currently defined by histology although future classification schemes will include molecular alterations. AA can be separated into subgroups, which share similar molecular profiles, age at diagnosis and median survival, based on 1p/19q co-deletion status and IDH mutation status. AA with co-deletion of chromosomes 1p and 19q and IDH mutation have the best prognosis. AA with IDH mutation and no 1p/19q co-deletion have intermediate prognosis and AA with wild-type IDH have the worst prognosis and share many molecular alterations with glioblastoma. Treatment of noncodeleted AA based on preliminary results from the CATNON clinical trial consists of maximal safe resection followed by radiotherapy with post-radiotherapy temozolomide (TMZ) chemotherapy. The role of concurrent TMZ and whether IDH1 subgroups benefit from TMZ is currently being evaluated in the recently completed randomized, prospective Phase III clinical trial, CATNON.

Systemic therapy for recurrent meningioma

INTRODUCTION

Meningioma comprise 20-30% of all primary brain tumors. Notwithstanding surgery and radiotherapy, a subset of patients will manifest recurrent meningioma. Systemic therapy is recommended only when further surgery and radiotherapy are not possible. No prospective study with a high level of evidence is available to inform as to recommendations regarding systemic therapy.

AREAS COVERED

We aim to summarize systemic therapies for recurrent meningioma. Expert commentary: Hydroxurea, temozolomide, irinotecan, the combination of cyclophosphamide/adriamycine/vincristine, interferon-alpha, somatostatin analogs, mifepristone, megestrol acetate, imatinib, erlotinib and gefitinib are considered as having limited efficacy. Potential activity of VEGF (vascular endothelial growth factor) inhibitors such as sunitinib, valatinib, and bevacizumab is suggested in small non-controlled studies and requires validation in randomized trials. The identification of new prognostic markers such as TERT promoter mutations and potential new therapeutic targets, such as KLF4, AKT1, TRAF7, and SMO mutations hopefully facilitate this endeavor.

Response Assessment in Neuro-Oncology working group and European Association for Neuro-Oncology recommendations for the clinical use of PET imaging in gliomas

This guideline provides recommendations for the use of PET imaging in gliomas. The review examines established clinical benefit in glioma patients of PET using glucose ((18)F-FDG) and amino acid tracers ((11)C-MET, (18)F-FET, and (18)F-FDOPA). An increasing number of studies have been published on PET imaging in the setting of diagnosis, biopsy, and resection as well radiotherapy planning, treatment monitoring, and response assessment. Recommendations are based on evidence generated from studies which validated PET findings by histology or clinical course. This guideline emphasizes the clinical value of PET imaging with superiority of amino acid PET over glucose PET and provides a framework for the use of PET to assist in the management of patients with gliomas.

Defining patients at risk for neoplastic meningitis: what parameters can be used to determine who should be treated?

While a growing body of clinical research is defining how better to treat neoplastic meningitis, questions regarding which parameters can be used to define who to treat remain. This discussion initiates the clinical core and practical components of the symposium.

Recurrent ganglioglioma in adults treated with BRAF inhibitors

Thirteen adult patients with temozolomide, surgery and radiation refractory ganglioglioma were screened for the BRAF V600E mutation. Three (23%) were found positive for the presence of the BRAF mutation and were treated with the BRAF inhibitor dabrafenib. Dabrafenib was well tolerated with no grade 3 or higher toxicity. The median number of cycles was 7 (a cycle was defined as 1 month of daily dabrafenib) and best response was stable disease in two patients and a partial response in one patient. Median progression-free survival was 7 months with a range of 4-10 months.

Neuro-oncology: a selected review of ASCO 2015 abstracts Chicago, IL, USA, 29 May–2 June 2015

ASCO, the American Society of Clinical Oncology, is the largest clinical oncology meeting that meets annually in the USA and is a venue at which new cancer clinical trials and research data are presented. The ASCO 2015 CNS tumors section comprising 3 days of posters and oral presentations and over 70 abstracts provides a contemporary summary of neuro-oncology including metastatic diseases of the CNS as well as primary brain tumors. This brief review selectively highlights presentations from this meeting in an organizational manner that reflects clinically relevant aspects of a large and multifaceted meeting.

Phase 1 dose escalation trial of the safety and pharmacokinetics of cabozantinib concurrent with temozolomide and radiotherapy or temozolomide after radiotherapy in newly diagnosed patients with high-grade gliomas

BACKGROUND

Cabozantinib inhibits mesenchymal-epithelial transition factor (MET) and vascular endothelial growth factor receptor 2 (VEGFR2) and has demonstrated activity in patients with recurrent glioblastoma, warranting evaluation of the addition of cabozantinib to radiotherapy (RT) and temozolomide (TMZ) for patients with newly diagnosed high-grade glioma.

METHODS

Cabozantinib doses of 40 mg and 60 mg were explored. Patients on the concurrent treatment arm received cabozantinib daily with standard TMZ and after RT continued cabozantinib daily with adjuvant TMZ. In the maintenance arm, patients who completed RT and ≥1 adjuvant cycle of TMZ continued adjuvant TMZ with added cabozantinib (3 schedules: days 1-28, days 1-14, or days 8-21).

RESULTS

A total of 26 patients (25 with recurrent glioblastoma and 1 patient with anaplastic astrocytoma) aged 30 to 72 years were enrolled (10 to the concurrent arm and 16 to the maintenance arm). The median number of post-RT TMZ cycles was 4.5 (range, 0-14 cycles) in the concurrent arm and 5.5 (range, 1-12 cycles) in the maintenance arm. Cabozantinib at a dose of 60 mg daily was the maximum administered dose and a dose of 40 mg daily was determined to be the maximum tolerated dose for both treatment arms (schedule of days 1-28). The most frequent grade 3/4 adverse events were thrombocytopenia (31% of patients), leukopenia (27% of patients, including 5 patients with neutropenia), and deep vein thrombosis and/or pulmonary embolism (23% of patients) (adverse events were graded according to the National Cancer Institute Common Terminology Criteria for Adverse Events [version 3.0]).

CONCLUSIONS

Cabozantinib at a dose of 40 mg daily with RT plus TMZ and post-RT TMZ for patients with newly diagnosed high-grade glioma was generally well tolerated, and demonstrated no pharmacokinetic interactions with concurrent TMZ. Given the strong theoretical rationale for combining anti-VEGF and anti-MET activity with standard therapy, cabozantinib at a dose of 40 mg daily warrants evaluation in combination with standard therapy for patients with newly diagnosed glioblastoma.

High-dose cytarabine salvage therapy for recurrent primary CNS lymphoma

Treatment of recurrent primary CNS lymphoma (PCNSL) though not standardized most often utilizes whole brain radiotherapy, re-challenge with high-dose methotrexate, or administration of an alkylating chemotherapy. High-dose cytarabine (HD-araC) has been advocated as an active agent in PCNSL but limited information exists regarding single agent activity in the recurrent setting. A retrospective review of 14 patients (10 males, 4 females: median age 60 years) with recurrent PCNSL treated at second recurrence with single agent HD-araC. HD-araC was administered at 3gm/m(2) over a 3-h infusion every 12 h for a total of 4 doses (defined as a cycle of therapy). GM-CSF was administered at conclusion of HD-araC. Patients were clinically and radiographically evaluated every 4-weeks. Common toxicity criteria Grade 3 or 4 toxicity included thrombocytopenia (11 patients; 79%), anemia (10; 71%), fatigue (8; 57%), mucositis (8; 57%), neutropenia (8; 57%) and neutropenic fever (5; 36%). No patient discontinued therapy due to toxicity nor were there any treatment-related deaths. Best response to HD-araC was stable disease in 6 patients (43%), partial response in 5 (36%) and progressive disease in 3 (21%). Median progression free survival 3 months (range 2-5 months; 95% CI 2-4 months) and progression free survival was 0% at 6-months. Median survival after onset of HD-araC was 12 months (range 3-18+ months; 95% CI 3-15 months). Single agent HD-araC has limited activity in recurrent PCNSL and is associated with significant toxicity in this small retrospective study.

Bevacizumab and other novel therapies for recurrent oligodendroglial tumors

Oligodendroglioma (WHO Grade 2) and anaplastic oligodendroglioma (WHO Grade 3) are glial tumors composed of neoplastic cellular elements that resemble oligodendrocytes. The treatment of recurrent, alkylator refractory oligodendroglial tumors is challenging given the paucity of effective treatment and lack of randomized controlled trials on which to base therapy. Notwithstanding the lack of prospective, randomized data, treatment of oligodendroglial tumors with bevacizumab can be recommended tentatively recognizing that preliminary studies suggest efficacy. Somatic mutations of the isocitrate dehydrogenase enzymes (IDH1 and IDH2) appear to play a critical role in the pathogenesis of most oligodendroglial tumors and agents that target these mutations are a potential therapeutic option. Additionally, reversal of CpG island hypermethylated phenotype status through inhibition of DNA methyltransferase with an inhibitor such as decitabine may provide a target for future studies.

Patterns of response to crizotinib in recurrent glioblastoma according to ALK and MET molecular profile in two patients

Two patients with an unmethylated MGMT promoter and IDH1 (R132H) wild-type recurrent glioblastoma were treated with crizotinib. Prolonged stabilization of the disease (17 months) was achieved in the first case. Interestingly, anaplastic lymphoma kinase (ALK) expression and c-MET protein overexpression was observed. Conversely, no response to crizotinib was obtained in the second case with MET protein overexpression and c-MET amplification but no ALK expression or ALK gene amplification. These case studies suggest that novel targeted ALK inhibitors may provide relevant clinical benefit in selected cases in which driver mutations are demonstrable.

Central nervous system cancers, version 2.2014. Featured updates to the NCCN Guidelines

The NCCN Guidelines for Central Nervous System Cancers provide multidisciplinary recommendations for the clinical management of patients with cancers of the central nervous system. These NCCN Guidelines Insights highlight recent updates regarding the management of metastatic brain tumors using radiation therapy. Use of stereotactic radiosurgery (SRS) is no longer limited to patients with 3 or fewer lesions, because data suggest that total disease burden, rather than number of lesions, is predictive of survival benefits associated with the technique. SRS is increasingly becoming an integral part of management of patients with controlled, low-volume brain metastases.

O6-methylguanine-DNA methyltransferase activity is associated with response to alkylating agent therapy and with MGMT promoter methylation in glioblastoma and anaplastic glioma

Background

CpG methylation in the O⁶-methylguanine-DNA methyltransferase (MGMT) promoter is associated with better outcome following alkylating agent chemotherapy in glioblastoma (GBM) and anaplastic glioma (AG). To what extent improved response reflects low or absent MGMT activity in glioma tissue has not been unequivocally assessed. This information is central to developing anti-resistance therapies.

Methods

We examined the relationship of MGMT activity in 91 GBMs and 84 AGs with progression-free survival (PFS) following alkylator therapy and with promoter methylation status determined by methylation-specific PCR (MSP).

Results

Cox regression analysis revealed that GBMs with high activity had a significantly greater risk for progression in dichotomous (P ≤ 0.001) and continuous (P ≤ 0.003) models, an association observed for different alkylator regimens, including concurrent chemo-radiation with temozolomide. Analysis of MGMT promoter methylation status in 47 of the GBMs revealed that methylated tumors had significantly lower activity (P ≤ 0.005) and longer PFS (P ≤ 0.036) compared to unmethylated tumors, despite overlapping activities. PFS was also significantly greater in methylated vs. unmethylated GBMs with comparable activity (P ≤ 0.005), and among unmethylated tumors with less than median activity (P ≤ 0.026), suggesting that mechanisms in addition to MGMT promote alkylator resistance. Similar associations of MGMT activity with PFS and promoter methylation status were observed for AGs.

Conclusions

Our results provide strong support for the hypotheses that MGMT activity promotes alkylator resistance and reflects promoter methylation status in malignant gliomas.

General significance

MGMT activity is an attractive target for anti-resistance therapy regardless of methylation status.

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Largest study to date of association of MGMT activity with treatment response.

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MGMT activity is inversely associated with alkylator response in malignant gliomas.

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Mean activity is significantly lower in MGMT promoter-methylated tumors.

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Better response in methylated tumors is unlikely due to lower MGMT activity alone.

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Supports the use of MGMT inhibitors to improve responsiveness to alkylator therapy.

Anaplastic glioma: current treatment and management

Anaplastic glioma (AG) is divided into three morphology-based groups (anaplastic astrocytoma, anaplastic oligodendroglioma, anaplastic oligoastrocytoma) as well as three molecular groups (glioma-CpG island methylation phenotype [G-CIMP] negative, G-CIMP positive non-1p19q codeleted tumors and G-CIMP positive codeleted tumors). The RTOG 9402 and EORTC 26951 trials established radiotherapy plus (procarbazine, lomustine, vincristine) chemotherapy as the standard of care in 1p/19q codeleted AG. Uni- or non-codeleted AG are currently best treated with radiotherapy only or alkylator-based chemotherapy only as determined by the NOA-04 trial. Maturation of NOA-04 and results of the currently accruing studies, CODEL (for codeleted AG) and CATNON (for uni or non-codeleted AG), will likely refine current up-front treatment recommendations for AG.

A selected review of abstracts from the 19th annual meeting of the Society for Neuro-Oncology

The Society for Neuro-Oncology is the largest neuro-oncology meeting in the USA that meets annually and provides a multiday venue presenting new brain cancer clinical trials and basic research data primarily pertaining to gliomas. The Society for Neuro-Oncology 2014 meeting comprising one education day, 3 days of presentation, over 200 oral presentations and 600 abstracts provides a comprehensive overview of neuro-oncology that includes metastatic diseases of the CNS as well as primary brain tumors. This summary attempts to highlight select abstracts presented at this year's meeting in a short review that provides a synopsis of a large and multifaceted meeting.

IFN-α for recurrent surgery- and radiation-refractory high-grade meningioma: a retrospective case series

AIM

Limited literature is available regarding the treatment of recurrent surgery- and radiation-refractory meningioma, and it primarily examines the treatment of low-grade (WHO grade 1) meningioma. Data regarding systemic therapy for recurrent high-grade meningioma are sparse. A retrospective case series of patients with recurrent WHO grade 2/3 meningioma treated with IFN-α following progression after surgery, radiotherapy and hydroxyurea was carried out, with the primary study objective of overall response rate, and median and 6-month progression-free survival (PFS).

PATIENTS & METHODS

35 patients (28 women and 17 men; median age 63 years; range: 36-86 years) with recurrent high-grade meningioma (WHO grade 2 [n = 22] or 3 [n = 13]) were treated with IFN-α (10 million units/m(2)) subcutaneously every 2 days; one cycle was operationally defined as 4 weeks of IFN-α. Patients had progressed radiographically after prior therapy with surgery (35 out of 35), radiotherapy (35 out of 35; external-beam radiotherapy: 35 out of 35; and stereotactic radiotherapy: 34 out of 35) and hydroxyurea chemotherapy (35 out of 35). One patient was also treated with a somatostatin analog before initiating IFN-α treatment.

RESULTS

Patients received one to 13 cycles (median: three) of IFN-α with moderate toxicity (100% of patients manifested grades 1-3 toxicity, of which only 20% were grade 3). There were no radiographic responses, 63% of patients had stable disease and 37% manifested progressive disease at first evaluation. PFS was 17% at 6 months (95% CI: 0.07-0.31; median PFS: 12 weeks; 95% CI: 8-20 weeks; range: 4-52 weeks). Following progression on IFN-α, the majority of patients (60%) were subsequently treated on an alternative therapy.

CONCLUSION

In this large retrospective series, IFN-α was moderately toxic, but appeared to have limited activity in patients with recurrent high-grade meningiomas.