Recent advances in Tumor Treating Fields (TTFields) therapy for glioblastoma.

Tumor Treating Fields (TTFields) therapy is a locoregional, anticancer treatment consisting of a noninvasive, portable device that delivers alternating electric fields to tumors through arrays placed on the skin. Based on efficacy and safety data from global pivotal (randomized phase III) clinical studies, TTFields therapy (Optune Gio) is US Food and Drug Administration-approved for newly diagnosed (nd) and recurrent glioblastoma (GBM) and Conformité Européenne-marked for grade 4 glioma. Here we review data on the multimodal TTFields mechanism of action that includes disruption of cancer cell mitosis, inhibition of DNA replication and damage response, interference with cell motility, and enhancement of systemic antitumor immunity (adaptive immunity). We describe new data showing that TTFields therapy has efficacy in a broad range of patients, with a tolerable safety profile extending to high-risk subpopulations. New analyses of clinical study data also confirmed that overall and progression-free survival positively correlated with increased usage of the device and dose of TTFields at the tumor site. Additionally, pilot/early phase clinical studies evaluating TTFields therapy in ndGBM concomitant with immunotherapy as well as radiotherapy have shown promise, and new pivotal studies will explore TTFields therapy in these settings. Finally, we review recent and ongoing studies in patients in pediatric care, other central nervous system tumors and brain metastases, as well as other advanced-stage solid tumors (ie, lung, ovarian, pancreatic, gastric, and hepatic cancers), that highlight the broad potential of TTFields therapy as an adjuvant treatment in oncology.

Virtual multi-institutional tumor board: a strategy for personalized diagnoses and management of rare CNS tumors.

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.

Exceptional and Sustained Response to Belzutifan in Von Hippel-Lindau Disease-Associated Central Nervous System Hemangioblastoma.

Von Hippiel-Lindau (VHL) disease is a rare genetic disorder characterized by a variety of benign and malignant neoplastic growths arising in multiple different organ systems. About 60%-84% of patients develop hemangioblastomas, benign tumors comprised of newly formed blood vessels that often occur in the central nervous system (CNS) and retinas. Treatment options for this disease were limited before the Food and Drug Administration (FDA) approval of belzutifan, a HIF2α inhibitor. We present a case of a 25-year-old woman with VHL who underwent treatment with belzutifan over 18 months. It was noted that her CNS lesions decreased significantly in size over the course of her treatment, and she had minimal adverse effects. Her excellent and sustained therapeutic response to the treatment highlights the real-world clinical benefit of belzutifan and the possibility that this could play a crucial role in treating VHL by postponing or completely avoiding repeated surgical and radiotherapeutic intervention and their associated comorbidities.

Progressive Multifocal Leukoencephalopathy Presenting as Primary CNS Malignancy in an Immunocompetent Patient.

Progressive multifocal leukoencephalopathy (PML) is an infection caused by the John Cunningham virus (JCV), usually in an immunocompromised host. We present the case of a 74-year-old male who presented with a six-week history of progressive memory loss, episodic confusion, and aphasia. Cranial nerve, motor, sensory, and coordination testing were unremarkable. Magnetic resonance imaging (MRI) of the brain and spectroscopy were concerning for primary CNS lymphoma vs. diffuse glioma. Microscopic examination after the patient underwent left frontal stereotactic brain biopsy was suggestive of a viral infection, and further testing with JCV DNA in-situ hybridization (ISH) confirmed the diagnosis of PML. The patient's condition started resolving without treatment. This case demonstrates, to our knowledge, the first known case of primary PML masquerading as CNS lymphoma in modern literature.

Glioblastoma: background, standard treatment paradigms, and supportive care considerations.

Glioblastoma is a brain tumor condition marked by rapid neurological and clinical demise, resulting in disproportionate disability for those affected. Caring for this group of patients is complex, intense, multidisciplinary in nature, and fraught with the need for expensive treatments, surveillance imaging, physician follow-up, and rehabilitative, psychological, and social support interventions. Few of these patients return to the workforce for any meaningful time frame, and because of the enormity of the financial burden that patients, their caregivers, and society face, utilization reviews become the focus of ethical scrutiny.

Levetiracetam enhances p53-mediated MGMT inhibition and sensitizes glioblastoma cells to temozolomide.

Antiepileptic drugs (AEDs) are frequently used to treat seizures in glioma patients. AEDs may have an unrecognized impact in modulating O(6)-methylguanine-DNA methyltransferase (MGMT), a DNA repair protein that has an important role in tumor cell resistance to alkylating agents. We report that levetiracetam (LEV) is the most potent MGMT inhibitor among several AEDs with diverse MGMT regulatory actions. In vitro, when used at concentrations within the human therapeutic range for seizure prophylaxis, LEV decreases MGMT protein and mRNA expression levels. Chromatin immunoprecipitation analysis reveals that LEV enhances p53 binding on the MGMT promoter by recruiting the mSin3A/histone deacetylase 1 (HDAC1) corepressor complex. However, LEV does not exert any MGMT inhibitory activity when the expression of either p53, mSin3A, or HDAC1 is abrogated. LEV inhibits malignant glioma cell proliferation and increases glioma cell sensitivity to the monofunctional alkylating agent temozolomide. In 4 newly diagnosed patients who had 2 craniotomies 7-14 days apart, prior to the initiation of any tumor-specific treatment, samples obtained before and after LEV treatment showed the inhibition of MGMT expression. Our results suggest that the choice of AED in patients with malignant gliomas may have an unrecognized impact in clinical practice and research trial design.