Sener, Uğur

Abstract BACKGROUND The IDH inhibitor vorasidenib was FDA-approved for treatment of IDH-mutant grade 2 gliomas in August 2024. We evaluated vorasidenib in patients with grade 3 and 4 IDH-mutant gliomas who would not have been eligible for the INDIGO trial. METHODS Retrospective review of patients with grade 3 or 4 IDH-mutant gliomas treated with vorasidenib between 9/1/24 and 5/31/25. Prior treatments, radiographic response, adverse events and seizure control were collected for each patient. RESULTS Thirty-two patients (median age 39.5, 46.9% female) met inclusion criteria. Tumor types included grade 3 oligodendroglioma (11, 34.4%), grade 3 astrocytoma (13, 40.6%) and grade 4 astrocytoma (8, 25%). Thirty patients had contrast-enhancement; 2 patients had non-enhancing tumor. Prior treatments included surgical resection (30, 93.8%), radiation (27, 84.4%), cytotoxic chemotherapy (25, 78.1%), bevacizumab (5, 15.6%), pembrolizumab (3, 9.4%), and ivosidenib (8, 25%). Four patients (12.5%) were naïve to systemic treatment at the time of vorasidenib initiation. Median duration of vorasidenib was 101.5 days (range 18-255) with 19 patients still on vorasidenib at the time of last follow-up. Seventeen patients (53.1%) had stable disease, 11 (34.4%) had progressive disease, 2 (6.3%) did not yet have response assessment, and 2 (6.3%) died. Grade 1 transaminitis occurred in 12 patients with no high grade transaminitis. Two patients developed lymphopenia; both were heavily pre-treated with multiple alkylating agents; no other hematologic toxicity was noted. One patient developed myalgias leading to vorasidenib discontinuation. Nine patients had fatigue, 4 headaches, 2 nausea, 2 decreased appetite. In patients with a history of epilepsy, there were no reported seizures. CONCLUSIONS Vorasidenib was well-tolerated in this heavily pre-treated cohort of grade 3–4 IDH-mutant gliomas, with low-grade transaminitis and fatigue being the most common toxicities. Preliminary results show disease stability in 53.1% of patients after a median of 3.5 months. Conclusions are limited by short-interval follow-up.

Abstract BACKGROUND CNS ependymal tumors rarely demonstrate mixed subependymal and ependymal pathology. The clinical course of these tumors is difficult to predict, but prior studies have identified TERT mutations and loss of chromosome 6 as poor prognostic factors in these tumors when located in the posterior fossa. METHODS In this retrospective single-institution study, patients with a diagnosis of mixed subependymoma/ependymoma were identified and chart reviewed to describe demographics, pathological findings, treatment courses and clinical outcomes. RESULTS Eleven patients (median age 57, 2 female, 9 male) were identified. Ten tumors were in the posterior fossa and 1 in the cervical spine. At diagnosis, 2 underwent gross total resection, 8 underwent subtotal resection, and 1 was only biopsied. Radiotherapy was administered to 5 patients at initial diagnosis (54Gy in 30 fractions). Systemic therapy (temozolomide and bevacizumab) was administered at recurrence to 2 patients. Loss of chromosome 6 was present in 5 /11 patients and TERT mutations were present in 4/11 patients, with both present in 3/11 patients. Median progression-free survival (mPFS) was 90.1 months (95% CI: 90.1–NA), with 3 progression events observed at 22, 90, and 107 months. Median follow-up duration was 27.9 months. Receiving radiotherapy had a longer mPFS (98 vs 22 months, p=0.15), although non-significant. At the time of data cut-off none of the patients were deceased. CONCLUSIONS Mixed subependymoma/ependymoma is a rare diagnosis with varying clinical outcomes. Our case series demonstrated that the majority of patients did not exhibit the previously identified poor prognostic factors. Although non-significant due to limited case numbers, radiotherapy was suggestive of longer mPFS.

Abstract BACKGROUND High grade astrocytoma with piloid features (HGAP) is a newly recognized tumor with a distinct DNA methylation profile. Its clinical course, treatment response, and outcomes remain poorly understood. METHODS We conducted a retrospective cohort study across three Mayo Clinic sites including adults with a HGAP diagnosis confirmed by DNA methylation profiling. RESULTS 17 patients were included (median age 38 years, Q1, Q3: 29–59; 9 male). DNA methylation-based tumor classification using the NCI/Bethesda classifier (v2) indicated a match to HGAP with high confidence (calibrated score >0.9) in 14 cases and was suggestive in 3 cases. All had MAPK pathway alterations (NF-1 mutation in 11, FGFR1 mutation in 2, KIAA1549::BRAF fusion in 2, FGFR1 transcript variant suggestive of internal tandem duplication in 1, KANK2::NTRK2 fusion in 1). All tumors also had CDKN2A/B homozygous deletion and 9 lost ATRX expression. Tumors were infratentorial (n=8), supratentorial (n=7), and spinal (n=2) at initial presentation. First line treatment included surgery followed by chemoradiation with temozolomide (n=12), surgery followed by radiation (n=4), radiation alone (n=1), and surgery alone (n=1). Gross total resection was achieved in 3/17, 8/17 had subtotal resection and 5/17 had biopsy. 14/17 received a median RT dose of 5700 cGy (range, 4005–6000) in 30 fractions. The median follow-up duration was 34.9 months. 8 patients experienced disease progression. The median progression-free survival (mPFS) was 30.3 months (95% CI: 15.4–NR). 6/8 underwent surgery; 3/8 underwent RT. Systemic therapies were administered in 5/8 (lomustine, bevacizumab, pembrolizumab, temozolomide, trametinib, tovorafenib). 3/17 patients died due to progressive disease with an OS of 54.2, 94.6 and 17.4 months, respectively. The mOS for the whole cohort was 54.2 months (95% CI: 54.2-NR). CONCLUSION While the optimal management of this newly recognized entity has yet to be established, our cohort demonstrates a clinical behavior consistent with CNS WHO grade 3, aligning with current WHO interpretations.

Abstract BACKGROUND The Response Assessment in Neuro-Oncology (RANO) was recently updated to RANO 2.0, which no longer requires follow-up imaging to confirm progression in recurrent glioma patients recieving immunotherapy, as previously recommended by iRANO. This study evaluates the utility of RANO 2.0 to determine whether radiographic progression on initial post-treatment MRI is sufficient to guide timely discontinuation of ineffective therapy. METHODS This retrospective study, conducted at Mayo Clinic, included patients ≥18 years receiving ≥2 cycles of off-label pembrolizumab for recurrent glioma between 1/1/2014 – 5/1/2025. Radiographic response was assessed using the first MRI performed ≥30 days after pembrolizumab initiation. Progression was defined as a ≥25% increase in the product of perpendicular diameters of the lesion, clear progression of non-measurable disease, new lesion appearance, clinical deterioration, or death. For suspected pseudo-progression, sequential MRIs were reviewed; if progression was confirmed, the original date was used. RESULTS Sixty-two patients were included (mean age: 46.1 years; 64.5% male), receiving pembrolizumab for a median duration of 2.8 (1.4 – 19.4) months. Median time to initial radiographic response assessment was 1.6 (1.1 – 3.5) months, and progression-free survival was 2.3 (0.7 – 15.2) months. Thirty-seven (59.7%) patients were identified with progression at initial evaluation. Among them, 11 were initially suspected of pseudo-progression, and continued pembrolizumab: 3 received additional radiation, 2 initiated bevacizumab, while 6 remained on their prior regimens [pembrolizumab only (3); pembrolizumab with bevacizumab (3)]. However, all were subsequently confirmed to have true progression, with a median delay of 1.4 (0.7 – 7.1) months until pembrolizumab discontinuation. No true pseudo-progression cases were observed. CONCLUSIONS Our findings support the clinical applicability of RANO 2.0 in recurrent glioma patients receiving pembrolizumab. Initial radiographic progression reliably predicted true progression, suggesting limited value in confirmatory follow-up imaging. Early recognition of treatment failure may reduce delays in initiating salvage therapies, along with associated toxicity and cost.

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 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 BACKGROUND Access to in-person evaluations is challenging for patients with glioma due to disease-related disability and distance from specialized neuro-oncology centers. Telehealth is an alternative to in-person evaluations, but acceptability of and therapy compliance with this model has not been prospectively evaluated. METHODS In this single-arm non-randomized pragmatic clinical trial, we compared patient satisfaction with telehealth and in-person assessments among patients with glioma undergoing chemotherapy with temozolomide. Participants acted as their own controls, alternating between telehealth and in-person visits. Patient satisfaction with care delivered was evaluated by Press-Ganey surveys with Likert response scales (1-5, 1=very poor, 5=very good). A digital pill diary (DPD) was implemented to track chemotherapy compliance. RESULTS We accrued 30 patients (median age 59, 38% female) between October 2024 and May 2025. Half of the patients (n=15) reported a primary residence greater than 150 miles from our institution. Surveys from 25 participants were reviewed, with 17/25 completing one or more surveys following an in-person visit, and 21/25 completing one or more surveys following a telehealth visit. Overall average Press-Ganey scores were similar between the two visit modalities with high scores (telehealth=4.8; in-person=4.7). Median scores for specific modalities were similarly highly rated: likelihood of recommending practice to others (telehealth=5.0; in-person=5.0), concern the care provider showed (telehealth=5.0, in-person=4.7), provider’s discussion of treatment options (telehealth=5.0, in-person=5.0), provider effort to include patients in decision-making (telehealth=5.0, in-person=5.0). DPDs used to monitor treatment compliance indicated adherence to all prescribed doses of temozolomide in 75/79 cycles; the other 4 (of 79) treatment cycles were halted per provider instructions. CONCLUSION This interim assessment demonstrates feasibility of treating patients with similar patient satisfaction of care delivered between telehealth and in-person visits. The DPD was effective in tracking chemotherapy administration. Additional results including visit type preference and acute care utilization data are maturing.

Abstract BACKGROUND The majority of pituitary neuroendocrine tumors (PitNETs) are effectively managed with medical therapy, surgery, and/or radiation therapy; however, a subset of pituitary adenomas exhibit aggressive behavior. Temozolomide is thought to be an effective treatment option for patients with PitNETs. METHODS We identified and retrospectively reviewed 11 patients with pituitary tumors treated with temozolomide. We then conducted a review of the literature, combining 114 previously published cases with our cohort. RESULTS 125 cases were identified with diagnoses of pituitary adenomas (n=45), aggressive pituitary tumors (n=61), and pituitary carcinoma (n=19) treated with temozolomide. 79 patients were male (68.1%) with a median age of 47.5 (range 9-72). A variety of tumor types were represented: 50 corticotroph adenomas (40.7%), 37 prolactinomas (30.1%), 22 hormone nonfunctioning adenomas (17.9%), 8 somatotroph adenomas (6.5%), 6 other functioning adenomas (4.9%), and 2 cases where the functional status was not mentioned. Median treatment duration was 9 cycles (n=91, 150-200 mg/m2 days 1-5, 28-day cycles; n=2, 75 mg/m2, days 1-21, 28-day cycles; n=1, 75 mg/m2 daily). 27 patients received concurrent therapy with a dopamine agonist/somatostatin analogue (n=10), other chemotherapy agent (n=9) or radiotherapy (n=8). Radiographic responses included stable disease (n=40), partial response (n=35), complete response (n=8), and progressive disease (n=30). Hormonal responses included complete response (n=13), partial response (n=32), and no response (n=16). 22 patients (47.8%; out of 46 patients where progression/recurrence was assessed) experienced progression/recurrence following temozolomide initiation with a median progression free survival (PFS) of 24 months. There was no significant association between MGMT methylation status and radiological or hormonal response. No unexpected toxicities were observed. CONCLUSION In this cohort, temozolomide was well-tolerated with a median PFS of 24 months. MGMT methylation status did not predict temozolomide response. Temozolomide is an option with a survival benefit for patients with PitNETs.