Citations

Abstract Pediatric, adolescent and young adult patients (Ped/AYA; 0–39 years) with meningiomas are underrepresented in neuro-oncology research, despite meningiomas being the second most common primary brain tumor in this age group. While DNA methylation-based models have advanced classification and prognostication in adults, their utility in younger populations remains uncertain. To address this gap, we aimed to evaluate the performance of current DNA methylation-based classification and recurrence prediction models in Ped/AYA patients with meningiomas and identify age-associated molecular differences. As part of this study, we analyzed 1,568 meningioma samples with DNA methylation and clinical data, including subsets with whole-exome and RNA sequencing. Patients were grouped into Ped/AYA (≤39 years, n = 213) and adult (>39 years, n = 1,355) cohorts. We assessed classifier performance, performed subgroup-specific model retraining, and compared molecular profiles across age groups. Our results showed that molecular classification differed significantly between age groups, with Ped/AYA tumors less frequently belonging to the most aggressive Proliferative Molecular Group. The DNA methylation-based recurrence model performed well in adults (AUC = 0.83) but poorly in the Ped/AYA cohort (AUC = 0.57). However, retraining the model on only younger patients improved performance (AUC = 0.75). In addition, Ped/AYA tumors exhibited significantly fewer chromosomal alterations, including lower frequencies of 1p, 6q, and 14q loss (p<0.05). Taken together, these findings indicate that predominantly adult-trained methylation models underperform in younger meningioma patients due to both biological divergence and exclusion from training datasets. Our findings underscore the need for age-specific molecular tools to improve prognostication and support personalized care across the lifespan in neuro-oncology.

Abstract MGMT is primarily inactivated via promoter methylation, but MGMT homozygous deletion (hmzdel) has been rarely reported as an alternative inactivating mechanism. Although functionally similar to a methylated MGMT promoter, MGMT hmzdel is associated with an unmethylated MGMT promoter test result reflecting the MGMT promoter status of the non-neoplastic cells invariably present in any tumor specimen. Thus, patients whose tumors have MGMT hmzdel (and unmethylated MGMT promoter) would be inaccurately predicted to lack benefit from alkylating chemotherapy based on MGMT promoter methylation testing alone. To evaluate the impact of this clinical scenario, we estimated the frequency and distribution of MGMT hmzdel in routine clinical testing of CNS tumors. Among 12,424 CNS tumors (3,044 with provided diagnosis of glioblastoma) tested using Oncoscan chromosomal microarray (2015-2025), 10 tumors (0.08%) had MGMT hmzdel: 8 with entire gene hmzdel and 2 with partial gene hmzdel favored to be inactivating (RNA-sequencing underway to exclude possibility of activating rearrangements). All tumors were supratentorial and non-midline. Median age at diagnosis was 58.5 years (range, 34-81), with 3:2 male:female. Of the 10 cases, 9 (of 3,044; 0.3%) had integrated diagnosis of glioblastoma, IDH-wildtype; the remaining case was a recurrent astrocytoma, IDH-mutant, CNS WHO grade 4. All 10 cases had loss of chromosome 10q and a highly unmethylated MGMT promoter by droplet digital PCR testing of downstream CpG sites 75-80/84-87, with median fraction abundance of 0.19% (range, 0-0.85). In summary, MGMT hmzdel only occurred in high-grade adult-type diffuse astrocytic gliomas, and is a rare potential pitfall for MGMT promoter methylation testing leading to inaccurate patient stratification. It is critical that laboratories performing routine CNS tumor copy number testing include MGMT in the curated list of reportable genes, and that clinicians be aware of this rare clinical scenario to accurately stratify patients despite misleading MGMT promoter test results.

Abstract BACKGROUND Tovorafenib is a type II rapidly accelerated fibrosarcoma (RAF) kinase inhibitor approved by the FDA in 2024 for relapsing or chemotherapy-refractory pediatric low-grade gliomas with mutations or alterations in the gene BRAF. There is potential for the use of this drug outside the pediatric population. We present a single institution case series of adults with CNS tumors with mutations or alterations in BRAF treated (off-label) with tovorafenib. METHODS Chart review. RESULTS 8 adult (age >18) patients were treated with tovorafenib at our institution between March 2024 and June 2025. Age range was 21-66 years old (median age 42). The population included 5 males and 3 females. Indications for treatment were pilocytic astrocytoma (n = 2), high grade astrocytoma with piloid features (HGAP) (n = 2), Erdheim-Chester disease (n = 2), pleomorphic xanthoastrocytoma (n = 1), and otherwise unclassified low-grade glioma (n = 1). All patients had mutations or alterations in BRAF including KIAA1549 fusion (n = 4), V600E mutation (n = 3), or GAB2 fusion (n = 1). Radiographic response to therapy was seen in 5/8 patients with 3 cases of radiographic stability (though one patient later progressed) and 2 cases of decrease in tumor size (in a pilocytic astrocytoma and in an HGAP). Both cases of decreased tumor size after treatment were in tumors with KIAA1549 fusions. Adverse effects of tovorafenib included fatigue (n=2), headache, myalgias, diplopia, cytopenias, and transaminitis (n=1). 3/8 patients had to pause or stop treatment due to adverse effects (intolerable headache, cytopenias, and transaminitis respectively). CONCLUSION Tovorafenib is a promising new treatment for CNS tumors with BRAF mutations or alterations. Our single institution case series suggests the efficacy of this drug for multiple tumor types in adults. Certain tumor subtypes such as KIAA1549 fusions may be more likely to benefit from this treatment.

Abstract BACKGROUND Bevacizumab, an anti-vascular endothelial growth factor (VEGF) monoclonal antibody, has emerged as a treatment for radiation necrosis. Doses ranging from 2.5 mg/kg to 15 mg/kg have been utilized however the optimal dosing remains inadequately studied. METHODS Retrospective review of adult patients with central nervous system tumors or brain metastasis treated with bevacizumab from 6/29/2021 to 7/31/2024. Patients were divided into those who received bevacizumab 7.5 mg/kg every 21 days and those who received bevacizumab 10 mg/kg every 21 days. The primary outcome was radiographic response as assessed by a blinded neuro-oncologist. Secondary outcomes included clinical response as documented in clinical notes, major adverse events including hemorrhage and thromboembolic events and re-dosing for recurrence of radiation necrosis beyond the 4 initially planned doses. RESULTS 104 patients were included (median age 59.3 years, 55% male); 53 patients in the 7.5 mg/kg group and 51 patients in the 10 mg/kg group. In the 7.5 mg/kg group, 1 patient had a complete response (CR), 16 patients had a partial response (PR), 32 patients had stable disease (SD), 3 patients had progression of disease, and 1 patient did not have repeat imaging. Of the 51 patients in the 10 mg/kg group, 3 patients had a CR, 10 patients had a PR, 27 patients had SD, 5 patients had progression of disease, and 6 patients did not have repeat imaging. There was no statistically significant difference in radiographic response between the two dosing groups (p = 0.42). Clinical response rates were higher in the 7.5 mg/kg group (65.2% vs 37.8%, p = 0.013). Major adverse events and need for re-dosing for radiation necrosis recurrence were comparable. CONCLUSION Bevacizumab 7.5 mg/kg was equally as efficacious as 10 mg/kg in terms of radiographic response and may offer a better clinical response for patients with radiation necrosis.

Abstract BACKGROUND Cognitive symptoms are common among cancer patients treated with intracranial radiation but inadequately assessed and suboptimally treated, owing in part to the time-consuming and resource-intensive nature of formal neuropsychological testing. Through remote administration of brief cognitive assessments and symptom-directed interventions, decentralization uniquely addresses this problem. METHODS In this single-site phase 2 fully decentralized clinical trial (NCT06377696), patients treated with radiation therapy (RT) for primary or metastatic brain tumors undergo cognitive evaluations with the application, Mayo Test Drive, and the Short Test of Mental Status (STMS; via telehealth or in person), at baseline and every three months for one year. Participants are provided wearable devices for health promotion. Half the participants are randomized to metformin to evaluate this agent’s efficacy in treating RT-related cognitive symptoms. Target enrollment is 100 participants. RESULTS Seventy-three patients (median age 45.5, 46% female) with brain tumors who received RT were enrolled May 2024 to May 2025. In this unplanned interim analysis, we evaluated the impact of decentralization on study participation. Thirty-six participants (49%) reported a primary residence greater than 150 miles from our institution. Seven patients were consented remotely, the remainder in person. Of 380 study-related visits (201 STMS, 179 treatment toxicity checks) 216 (57%) were completed by telehealth. Thirty-two of 336 (9.5%) study-related lab draws were completed at locations outside our institution. Wearable device data was continuously collected, with median 3022 steps tracked per patient per day on study. 190/250 (76%) quality-of-life surveys sent digitally were completed to date. CONCLUSION Decentralization implemented as part of this clinical trial enabled participation despite significant distance from our institution and facilitated study-related assessments through digital solutions, eliminating the need for travel. Our findings demonstrate the feasibility of conducting a fully decentralized supportive care trial in neuro-oncology, which can increase participation and accelerate evaluation of novel therapeutics.

Abstract BACKGROUND Bevacizumab, an anti-VEGF monoclonal antibody, has become a mainstay in the management of malignant gliomas. Multiple bevacizumab biosimilars have been approved since initial FDA approval of the reference agent and have seen widespread use due to reduced cost. However, real-world data evaluating comparability between reference and biosimilar agents have remained limited. METHODS We performed a retrospective analysis of patients treated with reference bevacizumab (Avastin) versus those receiving bevacizumab-bvzr, a widely used biosimilar agent (Zirabev) for the management of malignant glioma at our institution between 2019 and 2022. RESULTS A total of 161 patients were included in our final analysis; 97 received reference drug (Avastin) while 64 received the biosimilar agent (Zirabev). Demographics and baseline clinical characteristics between the two groups were similar. We performed survival analysis with post-progression survival (PPS) to ensure against lead-time bias. PPS was similar between the Avastin (median PPS 496 days) and Zirabev (median PPS 513 days) groups on univariate analysis (p=0.7654). Similarly, on multivariate Cox regression, there were no differences in PPS when comparing Avastin and Zirabev (HR 1.0673, p=0.6986). MGMT promoter methylation (HR 0.5709, p=0.0238), age at cancer diagnosis (HR 1.0356, p=0.0009), total dose of bevacizumab received (HR 0.9975, p=0.0087) and treatment with anticoagulation (HR 1.8086, p=0.0372) were significantly associated with PPS. Rates of therapy-related adverse effects were also similar between those receiving the reference drug and biosimilar agent (OR 0.9043, p=0.7824). However, concomitant treatment with antiplatelet therapy (OR 3.1447, p=0.0150) or anticoagulant therapy (OR 4.9069, p=0.0010) were significantly associated with increased risk for adverse effects. CONCLUSIONS Bevacizumab-bvzr demonstrated similar clinical efficacy and safety profile compared to reference bevacizumab in our institutional cohort. Concomitant treatment with antiplatelet therapy (OR 3.1447, p=0.0150) or anticoagulation (OR 4.9069, p=0.0010) were significantly associated with increased risk for adverse effects.

Abstract IDH-wildtype diffuse astrocytic gliomas with lower-grade histological features alongside specific genomic alterations (e.g., TERT promoter mutation, EGFR amplification, gain Chr7/loss Chr10) are presently diagnosed as glioblastoma, IDH-wildtype (GBM) under WHO 2021 criteria. Previous analyses categorized these into “early/evolving” or “surgically undersampled” GBMs. However, it remains unclear whether these tumors share identical clinical and prognostic features with histologic GBM. Data from IDH-wt molecular GBMs across six institutions were aggregated. Astrocytic IDH-wt tumors of any grade that lacked necrosis or microvascular proliferation on initial histopathology yet exhibited molecular alterations consistent with WHO 2021 GBM diagnosis, were included. Recursive partitioning analysis (RPA) was used to categorize patients into risk groups based on overall survival (OS). Among the 264 patients included, the median age was 60 years (IQR: 51-67), with 162 (61%) being male. Additionally, 210 (80%) were diagnosed since 2016, and 216 (82%) received chemoradiation plus adjuvant temozolomide (GBM-SOC). The median follow-up period was 3.9 years (95% CI: 3.4, 4.6). Identified univariate risk factors for worse survival included older age, biopsy-only status, EGFR amplification, absence of initial adjuvant treatment, low post-operative KPS, and tumor histologic grade of 3. RPA divided patients into four distinct survival groups (p<0.0001). The “best” risk group comprised lower grade (<=2) tumors (n=58, median OS (mOS): 40 months (95% CI: 33, NA)). The “second best” group included Grade 3 patients receiving GBM-SOC without steroids during initial RT (n=139, mOS: 25 months (95% CI: 22, 28)). The “second worst” group encompassed Grade 3 patients who were on steroids during initial RT while receiving GBM-SOC (n=38, mOS: 15 months (95% CI: 13, 20)). The “worst” group contained Grade 3 tumors that had not undergone SOC (n=29, mOS: 9 months (95% CI: 4, 26)). These data show that histologic features and treatment are strong indicators of patient outcomes.

Abstract BACKGROUND Understanding long-term sequelae of cancer care is critical. Cognitive impairment is a common and disabling survivorship issue. Because sex influences tumor biology, therapy exposure, and dementia risk, we examined whether cancer care for a prior malignancy alters late-life cognitive outcomes differently in males and females. METHODS We assessed adults ≥50 years, cognitively normal at study entry, from a longitudinal, population-based cohort (Mayo Clinic Study of Aging). Participants were linked to our institutional cancer registry (excluding non-melanoma skin cancers). Mild cognitive impairment (MCI) and dementia were adjudicated by consensus. We fitted multivariable Cox proportional-hazards models to estimate how prevalent cancer diagnosis influenced the risk of developing MCI/dementia. Sex-specific effects were determined by incorporating a cancer×sex interaction term and by generating separate hazard ratios. Analyses were controlled for age, APOE4 status, education, and presence of vascular/metabolic conditions. RESULTS 5793 MCSA participants (female: 49.4%, APOE4 positive: 27.5%) were included in the study, with a mean age of 73 years at study entry. Incident MCI was recorded in 866 participants, and 737 were diagnosed with incident dementia. About 20% (n=1176) of the cohort had a cancer diagnosis, most commonly prostate (n=423) and breast (n=277). There was no independent relationship between history of cancer and risk for MCI or dementia. We found that males with cancer had an increased risk for MCI (HR 1.28, 95% CI 1.04-1.57, p=0.003) and dementia (HR 1.29, 95% CI 1.04-1.6, p=0.053). Conversely, females with cancer had a lower risk for MCI (HR 0.79, 95% CI 0.61-1.01, p=0.063), although this was not statistically significant. CONCLUSIONS Our data suggests male cancer survivors may be more susceptible to cognitive impairment, independent of age, APOE4 status, education, and vascular/metabolic burden. Elucidating the hormonal, treatment-related, and systemic pathways driving this should be a priority for future mechanistic studies.

Abstract Zanubrutinib is a second-generation Bruton Tyrosine Kinase (BTK) inhibitor, FDA-approved for Mantle Cell Lymphoma (MCL), designed to be more selective and potentially better tolerated than first-generation agents like Ibrutinib. Progressive multifocal leukoencephalopathy (PML), a rare but severe complication, has not previously been reported with Zanubrutinib. We report a 74-year-old woman with a germline CHEK2 mutation and asymptomatic MCL (CD5+, cyclin D1+, Ki67 10–20%) diagnosed in 2016, managed with surveillance. In 2023, she was also diagnosed with localized breast cancer treated with lumpectomy and exemestane. Later that year, she developed new headaches. Brain MRI revealed diffuse bilateral pachymeningeal enhancement, suspicious for lymphomatous spread, without parenchymal involvement. By early 2024, follow-up imaging showed stable pachymeningeal enhancement with new scattered punctate right frontal subcortical lesions, coinciding with systemic MCL progression. Spinal imaging revealed epidural and bone marrow involvement; CSF was negative for malignancy. Zanubrutinib was initiated in March 2024. By August 2024, new bilateral frontal and parietal fuzzy hyperintense and faintly enhancing white matter lesions emerged, while prior punctate lesions regressed. Biopsy confirmed PML with JC virus DNA by in situ hybridization and absence of B-cell clonality. Zanubrutinib was discontinued. Follow-up imaging showed regression of lesions without new enhancement, consistent with immune reconstitution. The initial subcortical punctate lesions remained stable. In 2025, she was diagnosed with localized pancreatic adenocarcinoma, precluding cytotoxic therapy initially due to concern for PML reactivation. However, as of May 2025, neuroimaging remains stable, and patient was started on palliative gemcitabine/paclitaxel. This is the first reported case of PML associated with Zanubrutinib. It underscores the importance of vigilance for PML even in patients without overt immunosuppression, especially those with overlapping malignancies and treatment exposures in the correct clinical context.

Abstract Recent studies demonstrate that platelet factor 4 (PF4), an abundant platelet-derived chemokine in young plasma, can reduce neuroinflammation, enhance cognition, and rejuvenate peripheral immunity in aged mice. Intriguingly, neuroimmune markers modulated by PF4—such as Iba1, CD68, and C1q—also contribute to glioma progression. Age-associated immune shifts, including increased myeloid-to-lymphocyte ratios, T cell depletion, and systemic inflammation, are similarly implicated in cancer development. Here, we show that systemic administration of PF4 significantly extends survival in aged (18–23 month-old) glioma-bearing mice and trends toward improved outcomes in young (2–3 month-old) counterparts. Longitudinal IVIS imaging revealed reduced tumor-associated luminescence in PF4-treated animals, particularly in aged males and females. Histological analysis demonstrated downregulation of microglial and macrophage activation markers within the tumor microenvironment. Ongoing studies utilizing flow cytometry, cytokine profiling, and novel PF4-delivery platforms aim to further elucidate its effects on both central and peripheral immunity. These findings suggest that age-related immune modulation may be leveraged to delay glioma progression, positioning PF4 as a promising therapeutic at the intersection of aging, immunology, and neuro-oncology.