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Background Methotrexate (MTX) is administered for the treatment of central nervous system (CNS) hematologic cancers, prophylaxis of CNS dissemination of certain hematological cancers, and in solid tumor leptomeningeal disease. MTX treatment can be limited by CNS toxicity. Dextromethorphan is used to treat MTX neurotoxicity, with most data derived from pediatric case series. In this report, we profile 4 adult patients who developed intrathecal (IT) MTX neurotoxicity to better characterize their response to dextromethorphan treatment. Methods A case series of 4 patients who developed neurologic symptoms attributed to IT MTX neurotoxicity subsequently treated with dextromethorphan was devised. Demographic data, clinical characteristics, electroencephalography results, magnetic resonance imaging, cerebrospinal fluid (CSF) characteristics, and dextromethorphan treatment outcomes were described. Results Of the 4 patients developing MTX neurotoxicity, neurologic symptoms developed over a timeframe of 2 to 14 days from the precedent MTX exposure. Radiologic phenotypes included subcortical white matter diffusion-restricting lesions, bi-hemispheric subcortical white matter T2-FLAIR hyperintensities, as well as other findings described in the report. Time elapsed from initiation of dextromethorphan to neurologic symptom resolution ranged from 1 to 2 days. Conclusions The profiles of 4 adult patients developing suspected IT MTX neurotoxicity syndromes with subsequent response to Dextromethorphan add further data to guide the management of such patients. [ABSTRACT FROM AUTHOR]

Simple Summary: For patients with solid tumor brain metastases that progress after whole-brain radiotherapy, there are limited treatment options. The aim of our prospective trial was to examine the usage of bevacizumab as salvage therapy in this specific patient population, with primary endpoints being radiologic response, survival, safety, and quality of life. Our data show that bevacizumab was well tolerated, maintained quality of life, and improved overall survival with radiologic response. Patients with solid tumor brain metastases that progress after whole-brain radiation have limited options. This prospective trial investigated the efficacy, safety, and tolerability of bevacizumab as salvage therapy in this population. Eligible patients received bevacizumab 10 mg/kg intravenously every 2 weeks until progression. The primary endpoint was radiologic response using Response Assessment in Neuro-Oncology (RANO) criteria. The secondary endpoints were progression-free survival (PFS), overall survival (OS), duration of response, and safety. Quality of life (QOL) was studied using the Functional Assessment of Cancer Therapy-Brain (FACT-Br) scale. Twenty-seven patients were enrolled, with twenty-four having evaluable data for response. The majority of histologies (n = 21, 78%) were breast cancer. The remaining histologies were non-small-cell lung cancer (n = 4, 15%), neuroendocrine cancer (n = 1, 3%), and papillary fallopian serous adenocarcinoma (n = 1, 3%). Eighteen patients had radiologic response, with two patients demonstrating partial response (8.33%) and sixteen patients demonstrating stable disease (66.7%). The median duration of response was 203 days. PFS at 6 months was 46%, median PFS was 5.3 m, and median OS was 9.5 m. Treatment was well tolerated, with six patients experiencing grade 3 lymphopenia and hypertension. There was one grade 3 thromboembolism. QOL was not negatively impacted. Bevacizumab is a safe and feasible salvage treatment with durable response and favorable overall survival for patients with progressive brain metastases after whole-brain radiation. [ABSTRACT FROM AUTHOR]

Background: Tumor Treating Fields (TTFields) Therapy is an FDA-approved therapy in the first line and recurrent setting for glioblastoma. Despite Phase 3 evidence showing improved survival with TTFields, it is not uniformly utilized. We aimed to examine patient and clinician views of TTFields and factors shaping utilization of TTFields through a unique research partnership with medical neuro oncology and medical social sciences. Methods: Adult glioblastoma patients who were offered TTFields at a tertiary care academic hospital were invited to participate in a semi-structured interview about their decision to use or not use TTFields. Clinicians who prescribe TTFields were invited to participate in a semi-structured interview about TTFields. Results: Interviews were completed with 40 patients with a mean age of 53 years; 92.5% were white and 60% were male. Participants who decided against TTFields stated that head shaving, appearing sick, and inconvenience of wearing/carrying the device most influenced their decision. The most influential factors for use of TTFields were the efficacy of the device and their clinician’s opinion. Clinicians (N = 9) stated that TTFields was a good option for glioblastoma patients, but some noted that their patients should consider the burdens and benefits of TTFields as it may not be the desired choice for all patients. Conclusions: This is the first study to examine patient decision making for TTFields. Findings suggest that clinician support and efficacy data are among the key decision-making factors. Properly understanding the path to patients’ decision making is crucial in optimizing the use of TTFields and other therapeutic decisions for glioblastoma patients. [ABSTRACT FROM AUTHOR]

Purpose: Multidisciplinary tumor boards (MTBs) integrate clinical, molecular, and radiological information and facilitate coordination of neuro-oncology care. During the COVID-19 pandemic, our MTB transitioned to a virtual and multi-institutional format. We hypothesized that this expansion would allow expert review of challenging neuro-oncology cases and contribute to the care of patients with limited access to specialized centers. Methods: We retrospectively reviewed records from virtual MTBs held between 04/2020–03/2021. Data collected included measures of potential clinical impact, including referrals to observational or therapeutic studies, referrals for specialized neuropathology analysis, and whether molecular findings led to a change in diagnosis and/or guided management suggestions. Results: During 25 meetings, 32 presenters discussed 44 cases. Approximately half (n = 20; 48%) involved a rare central nervous system (CNS) tumor. In 21% (n = 9) the diagnosis was changed or refined based on molecular profiling obtained at the NIH and in 36% (n = 15) molecular findings guided management. Clinical trial suggestions were offered to 31% (n = 13), enrollment in the observational NCI Natural History Study to 21% (n = 9), neuropathology review and molecular testing at the NIH to 17% (n = 7), and all received management suggestions. Conclusion: Virtual multi-institutional MTBs enable remote expert review of CNS tumors. We propose them as a strategy to facilitate expert opinions from specialized centers, especially for rare CNS tumors, helping mitigate geographic barriers to patient care and serving as a pre-screening tool for studies. Advanced molecular testing is key to obtaining a precise diagnosis, discovering potentially actionable targets, and guiding management. [ABSTRACT FROM AUTHOR]

As many as 80% of low-grade gliomas (LGGs) present with seizures, negatively impacting quality of life. While seizures are associated with gliomas regardless of grade, the importance of minimizing impact of seizures for patients with low grade tumors cannot be understated given the prolonged survival period in this population. The objective of this systematic review and meta-analysis was to summarize existing literature and identify factors associated with post-operative seizure control (defined as Engel I classification) in patients with LGGs, with a focus on pre-operative factors. Patient data extracted include tumor location and histology, pre-operative anti-seizure medication use, extent of resection (EOR), adjuvant treatment, pre-operative seizure type, duration, and frequency, and post-operative Engel classification. A random-effects model was used to calculate the effects of EOR, pre-operative seizure duration, adjuvant radiation, and adjuvant chemotherapy on post-operative seizure control. The effect of tumor location and histology on post-operative Engel I classification was determined using contingency analyses. Thirteen studies including 1628 patients with seizures were included in the systematic review. On meta-analyses, Engel I classification was associated with pre-operative seizure type (OR = 0.79 (0.63–0.99), p = 0.0385, focal versus generalized), frontal lobe LGGs (OR = 1.5 (1.1–2.0), p = 0.0195), and EOR (OR (95% CI) = 4.5 (2.3–6.7), p < 0.0001 gross-total versus subtotal). Pre-operative seizure duration less than one year, adjuvant radiation, adjuvant chemotherapy, and tumor histology were not associated with achieving Engel I classification. In addition to the known effects of EOR, Engel I classification is less likely to be achieved in patients with focal pre-operative seizures and more likely to be achieved in patients with frontal lobe LGGs. [ABSTRACT FROM AUTHOR]

MGMT promoter methylation testing is required for prognosis and predicting temozolomide response in gliomas. Accurate results depend on sufficient tumor cellularity, but histologic estimates of cellularity are subjective. We sought to determine whether driver mutation variant allelic frequency (VAF) could serve as a more objective metric for cellularity and identify possible false-negative MGMT samples. Among 691 adult-type diffuse gliomas, MGMT promoter methylation was assessed by pyrosequencing (N = 445) or DNA methylation array (N = 246); VAFs of TERT and IDH driver mutations were assessed by next generation sequencing. MGMT results were analyzed in relation to VAF. By pyrosequencing, 56% of all gliomas with driver mutation VAF ≥ 0.325 had MGMT promoter methylation, versus only 37% with VAF < 0.325 (p < 0.0001). The mean MGMT promoter pyrosequencing score was 19.3% for samples with VAF VAF ≥ 0.325, versus 12.7% for samples with VAF < 0.325 (p < 0.0001). Optimal VAF cutoffs differed among glioma subtypes (IDH wildtype glioblastoma: 0.12–0.18, IDH mutant astrocytoma: ~0.33, IDH mutant and 1p/19q co-deleted oligodendroglioma: 0.3–0.4). Methylation array was more sensitive for MGMT promoter methylation at lower VAFs than pyrosequencing. Microscopic examination tended to overestimate tumor cellularity when VAF was low. Re-testing low-VAF cases with methylation array and droplet digital PCR (ddPCR) confirmed that a subset of them had originally been false-negative. We conclude that driver mutation VAF is a useful quality assurance metric when evaluating MGMT promoter methylation tests, as it can help identify possible false-negative cases. [ABSTRACT FROM AUTHOR]

Purpose: Survival is dismal for bevacizumab refractory high-grade glioma patients. We prospectively investigated the efficacy of re-irradiation, bevacizumab, and temozolomide in bevacizumab-naïve and bevacizumab-exposed recurrent high-grade glioma, without volume limitations, in a single arm trial. Methods: Recurrent high-grade glioma patients were stratified based on WHO grade (4 vs. < 4) and prior exposure to bevacizumab (yes vs. no). Eligible patients received radiation using a simultaneous integrated boost technique (55 Gy to enhancing disease, 45 Gy to non-enhancing disease in 25 fractions) with bevacizumab 10 mg/kg every 2 weeks IV and temozolomide 75 mg/m2 daily followed by maintenance bevacizumab 10 mg/kg every 2 weeks and temozolomide 50 mg/m2 daily for 6 weeks then a 2 week holiday until progression. Primary endpoint was overall survival. Quality of life was studied using FACT-Br and FACT-fatigue scales. Results: Fifty-four patients were enrolled. The majority (n = 36, 67%) were bevacizumab pre-exposed GBM. Median OS for all patients was 8.5 months and 7.9 months for the bevacizumab pre-exposed GBM group. Patients ≥ 36 months from initial radiation had a median OS of 13.3 months compared to 7.5 months for those irradiated < 36 months earlier (p < 0.01). FACT-Br and FACT-Fatigue scores initially declined during radiation but returned to pretreatment baseline. Treatment was well tolerated with 5 patients experiencing > grade 3 lymphopenia and 2 with > grade 3 thrombocytopenia. No radiographic or clinical radiation necrosis occurred. Conclusions: Re-irradiation with bevacizumab and temozolomide is a safe and feasible salvage treatment for patients with large volume bevacizumab-refractory high-grade glioma. Patients further from their initial radiotherapy may derive greater benefit with this regimen. [ABSTRACT FROM AUTHOR]

A golden opportunity to treat glioblastoma: Glioblastoma (GBM) is a difficult cancer to treat, partly due to the blood-brain and blood-tumor barriers. Kumthekar et al. studied NU-0129, spherical nucleic acids consisting of gold nanoparticle cores conjugated with small interfering RNA oligonucleotides targeting Bcl2L12, for the treatment of GBM. After performing toxicology studies in cynomolgus monkeys, the authors conducted a first-in-human single-arm clinical trial of very low-dose NU-0129 in eight patients with recurrent GBM. By analyzing gold accumulation, the authors found that NU-0129 passed through the blood-brain barrier and accumulated in the tumor, where it reduced Bcl2L12 protein abundance. These results suggest that spherical nucleic acid nanoconjugates can potentially treat GBM. Glioblastoma (GBM) is one of the most difficult cancers to effectively treat, in part because of the lack of precision therapies and limited therapeutic access to intracranial tumor sites due to the presence of the blood-brain and blood-tumor barriers. We have developed a precision medicine approach for GBM treatment that involves the use of brain-penetrant RNA interference–based spherical nucleic acids (SNAs), which consist of gold nanoparticle cores covalently conjugated with radially oriented and densely packed small interfering RNA (siRNA) oligonucleotides. On the basis of previous preclinical evaluation, we conducted toxicology and toxicokinetic studies in nonhuman primates and a single-arm, open-label phase 0 first-in-human trial (NCT03020017) to determine safety, pharmacokinetics, intratumoral accumulation and gene-suppressive activity of systemically administered SNAs carrying siRNA specific for the GBM oncogene Bcl2Like12 (Bcl2L12). Patients with recurrent GBM were treated with intravenous administration of siBcl2L12-SNAs (drug moniker: NU-0129), at a dose corresponding to 1/50th of the no-observed-adverse-event level, followed by tumor resection. Safety assessment revealed no grade 4 or 5 treatment–related toxicities. Inductively coupled plasma mass spectrometry, x-ray fluorescence microscopy, and silver staining of resected GBM tissue demonstrated that intravenously administered SNAs reached patient tumors, with gold enrichment observed in the tumor-associated endothelium, macrophages, and tumor cells. NU-0129 uptake into glioma cells correlated with a reduction in tumor-associated Bcl2L12 protein expression, as indicated by comparison of matched primary tumor and NU-0129–treated recurrent tumor. Our results establish SNA nanoconjugates as a potential brain-penetrant precision medicine approach for the systemic treatment of GBM. [ABSTRACT FROM AUTHOR]

Purpose of Review: Glioblastoma multiforme (GBM) is the most common primary malignant brain tumor in adults with a dismal prognosis despite aggressive multimodal management thus novel treatments are urgently needed. Gene therapy is a versatile treatment strategy being investigated in multiple cancers including GBM. In gene therapy, a variety of vectors or 'carriers' are used to deliver genes designed for different anti-tumoral effects. Gene delivery vehicles and approaches to treatment will be addressed in this review. Recent Findings: The most commonly studied vectors are viral based, however, driven by advances in biomedical engineering, mesenchymal and neural stem cells, as well as multiple different types of nanoparticles have been developed to improve tumor tropism and also increase gene transfer into tumor cells. Different genes have been studied including suicide genes, which convert non-toxic prodrug into cytotoxic drug; immunomodulatory genes, which stimulate the immune system; and tumor suppressor genes which repair the defect that allow cells to divide unchecked. Summary: Gene therapy may be a promising treatment strategy in neuro-oncology as it is versatile and flexible due to the ability to tailor vectors and genes for specific therapeutic activity. Pre-clinical studies and clinical trials have demonstrated feasibility and safety of gene therapy; however, further studies are required to determine efficacy. [ABSTRACT FROM AUTHOR]

Low-grade gliomas are infiltrative primary brain tumors that most commonly occur in young adults. They are relatively slow growing compared with high-grade gliomas. The World Health Organization classification system was updated in 2016 to define low-grade gliomas using molecular markers in addition to histology. IDH mutation is an independent marker associated with better outcomes. Management is individualized based on tumor histology, molecular characterization, and patient risk factors. Given the longer course and natural history of low-grade gliomas, the goals of treatment should be to prolong overall survival and minimize neurocognitive decline. Early maximum safe resection is the first line of treatment. While low-risk patients may be followed with observation after surgery, patients with high-risk factors (subtotal resection, age > 40 years, IDH wild-type tumors) should be treated with radiation and chemotherapy. Improved understanding of the molecular characteristics of low-grade gliomas will further guide risk stratification and allow the identification of treatment approaches that are more effective and less toxic. [ABSTRACT FROM AUTHOR]

Opinion Statement: Corticosteroids have been essential in the management of brain tumor patients for decades, primarily for the treatment of peritumoral cerebral edema and its associated neurologic deficits. Dexamethasone is the drug of choice with standard practice being administration up to four times per day, however, because of its long biologic half-life and high potency, once or twice a day dosing is likely adequate in patients without elevated intracranial pressure. The length of corticosteroid treatment should be limited to the shortest period of time to minimize the risk of potential toxicities that can significantly affect quality of life, as well as to avoid a possible detrimental impact on survival in high-grade glioma patients and abrogation of the effect of immunotherapy. Agents such as bevacizumab should be considered in patients who are unable to wean completely off of steroids as well as those who have symptomatic edema and are on immunotherapy. Several other agents have been studied without much success. An increased understanding of the complex pathophysiology of peritumoral vasogenic edema is critically needed to discover new agents that are safer and more effective. [ABSTRACT FROM AUTHOR]

Opinion Statement: Treating patients with brain tumors can be divided into tumor-directed therapies, the management of tumor-related symptoms and complications and the psychosocial aspect of patient care. In this review, we will discuss the management of disease and treatment-related complications, which can negatively impact patient quality of life and functional status. Brain edema is a common complication or brain tumors and often causes more symptoms than the tumor itself. Treatment options are limited to the use of corticosteroids, which although effective have a plethora of side effects, so the goal should be the lowest dose that maximizes symptoms. Seizures are more common in lower grade brain tumors and treatment should be limited to patients who have seizures using agents that do not affect the metabolism of other drugs, especially chemotherapies. Blood clots are also common in patients and although there is a "fear" of tumoral bleeding, this is not a frequent occurrence; hence, using anticoagulants should be routinely used in patients who experience this complication. [ABSTRACT FROM AUTHOR]