Vorasidenib in IDH1- or IDH2-Mutant Low-Grade Glioma.

BACKGROUND: Isocitrate dehydrogenase (IDH)-mutant grade 2 gliomas are malignant brain tumors that cause considerable disability and premature death. Vorasidenib, an oral brain-penetrant inhibitor of mutant IDH1 and IDH2 enzymes, showed preliminary activity in IDH-mutant gliomas. METHODS: In a double-blind, phase 3 trial, we randomly assigned patients with residual or recurrent grade 2 IDH-mutant glioma who had undergone no previous treatment other than surgery to receive either oral vorasidenib (40 mg once daily) or matched placebo in 28-day cycles. The primary end point was imaging-based progression-free survival according to blinded assessment by an independent review committee. The key secondary end point was the time to the next anticancer intervention. Crossover to vorasidenib from placebo was permitted on confirmation of imaging-based disease progression. Safety was also assessed. RESULTS: A total of 331 patients were assigned to receive vorasidenib (168 patients) or placebo (163 patients). At a median follow-up of 14.2 months, 226 patients (68.3%) were continuing to receive vorasidenib or placebo. Progression-free survival was significantly improved in the vorasidenib group as compared with the placebo group (median progression-free survival, 27.7 months vs. 11.1 months; hazard ratio for disease progression or death, 0.39; 95% confidence interval [CI], 0.27 to 0.56; P<0.001). The time to the next intervention was significantly improved in the vorasidenib group as compared with the placebo group (hazard ratio, 0.26; 95% CI, 0.15 to 0.43; P<0.001). Adverse events of grade 3 or higher occurred in 22.8% of the patients who received vorasidenib and in 13.5% of those who received placebo. An increased alanine aminotransferase level of grade 3 or higher occurred in 9.6% of the patients who received vorasidenib and in no patients who received placebo. CONCLUSIONS: In patients with grade 2 IDH-mutant glioma, vorasidenib significantly improved progression-free survival and delayed the time to the next intervention. (Funded by Servier; INDIGO ClinicalTrials.gov number, NCT04164901.).

Dose-dependent efficacy of bevacizumab in recurrent glioblastoma.

BACKGROUND: Bevacizumab (BEV), at a standard dose of 10 mg/kg every 2 weeks is associated with prolonged progression-free survival (PFS) but no improvement in overall survival (OS) in recurrent glioblastoma (rGBM). Few studies have examined the potential dose-dependent efficacy of BEV. In Ontario, reimbursement for the costs of BEV varies, and as a result, our practice began to routinely use lower dose regimens. The main aim of this study was to ensure that there was no harm to patients who received the low dose protocol. METHODS: A single-center retrospective study of patients given BEV for rGBM between 2015 and 2020 was performed. Clinical and treatment data including BEV dose regimen [SD (10 mg/kg every 2 weeks) vs. LD (5 mg/kg every 2-3 weeks or 10 mg/kg every 3 weeks)] received at the time of rGBM diagnosis were captured. Overall survival (OS) and progression-free survival (PFS) on BEV were compared using the Kaplan-Meier product-limit method. Log-rank test was used to compare potential predictive factors. Cox regression model was performed for multivariable analysis of OS and PFS. RESULTS: A total of 96 patients were included with a median follow-up duration of 6.84 months (range 1.12-50.63 months) from the date of the first infusion. The LD group consisted of 55 of the 96 patients. By virtue of funding mechanisms for BEV, the median age in the LD group was significantly higher (62 vs. 54 years p = 0.009). There was no difference in MGMT status between the two groups (p = 0.60). The LD group had prolonged median PFS (5.89 months versus 3.22 months; p = 0.0112) and OS (10.23 months versus 6.28 months; p = 0.0010). Multivariable analysis including the dose of BEV, the extent of resection, gender, and age revealed that standard dose of BEV, subtotal resection, and female sex were associated with worse overall survival. Nine patients in the SD group vs. 18 patients in the LD group reported an adverse event related to BEV. CONCLUSION: For patients with recurrent GBM, we found that a low dose regimen of BEV was associated with prolonged OS and PFS compared to the standard dose regimen. Lower dose schedules may be a better and more cost-effective option for patients with rGBM. Lower costs might provide more equitable access to this very important palliative drug.

Short-Course Radiation plus Temozolomide in Elderly Patients with Glioblastoma.

BACKGROUND: Glioblastoma is associated with a poor prognosis in the elderly. Survival has been shown to increase among patients 70 years of age or younger when temozolomide chemotherapy is added to standard radiotherapy (60 Gy over a period of 6 weeks). In elderly patients, more convenient shorter courses of radiotherapy are commonly used, but the benefit of adding temozolomide to a shorter course of radiotherapy is unknown. METHODS: We conducted a trial involving patients 65 years of age or older with newly diagnosed glioblastoma. Patients were randomly assigned to receive either radiotherapy alone (40 Gy in 15 fractions) or radiotherapy with concomitant and adjuvant temozolomide. RESULTS: A total of 562 patients underwent randomization, 281 to each group. The median age was 73 years (range, 65 to 90). The median overall survival was longer with radiotherapy plus temozolomide than with radiotherapy alone (9.3 months vs. 7.6 months; hazard ratio for death, 0.67; 95% confidence interval [CI], 0.56 to 0.80; P<0.001), as was the median progression-free survival (5.3 months vs. 3.9 months; hazard ratio for disease progression or death, 0.50; 95% CI, 0.41 to 0.60; P<0.001). Among 165 patients with methylated O6-methylguanine-DNA methyltransferase (MGMT) status, the median overall survival was 13.5 months with radiotherapy plus temozolomide and 7.7 months with radiotherapy alone (hazard ratio for death, 0.53; 95% CI, 0.38 to 0.73; P<0.001). Among 189 patients with unmethylated MGMT status, the median overall survival was 10.0 months with radiotherapy plus temozolomide and 7.9 months with radiotherapy alone (hazard ratio for death, 0.75; 95% CI, 0.56 to 1.01; P=0.055; P=0.08 for interaction). Quality of life was similar in the two trial groups. CONCLUSIONS: In elderly patients with glioblastoma, the addition of temozolomide to short-course radiotherapy resulted in longer survival than short-course radiotherapy alone. (Funded by the Canadian Cancer Society Research Institute and others; ClinicalTrials.gov number, NCT00482677 .).

Temozolomide and seizure outcomes in a randomized clinical trial of elderly glioblastoma patients.

INTRODUCTION: Tumor-related epilepsy may respond to chemotherapy. In a previously-published multi-centre randomized clinical trial of 562 elderly glioblastoma patients, temozolomide plus short-course radiotherapy conferred a survival benefit over radiotherapy alone. Seizure outcomes were not reported. METHODS: We performed an unplanned secondary analysis of this trial's data. The trial design has been previously reported. Seizures were recorded by clinicians as adverse events and by patients in quality of life questionnaires. A Chi-square test of seizure rates between the two groups (α = 0.05) and a Kaplan-Meier estimator of time-to-first self-reported seizure were planned. RESULTS: Almost all patients were followed until they died. In the radiotherapy alone group, 68 patients (24%) had a documented or self-reported seizure versus 83 patients (30%) in the temozolomide plus radiotherapy group, Chi-square analysis showed no difference (p = 0.15). Patients receiving radiotherapy alone tended to develop seizures earlier than those receiving temozolomide plus radiotherapy (p = 0.054). Patients with seizures had shorter overall survival than those without seizures (hazard ratio 1.24, p = 0.02). CONCLUSIONS: This study was not powered to detect differences in seizure outcomes, but temozolomide seemed to have minimal impact on seizure control in elderly patients with glioblastoma. CLINICAL TRIAL REGISTRATION: NCT00482677 2007-06-05.

Therapeutic efficacy of potent neutralizing HIV-1-specific monoclonal antibodies in SHIV-infected rhesus monkeys.

Human immunodeficiency virus type 1 (HIV-1)-specific monoclonal antibodies with extraordinary potency and breadth have recently been described. In humanized mice, combinations of monoclonal antibodies have been shown to suppress viraemia, but the therapeutic potential of these monoclonal antibodies has not yet been evaluated in primates with an intact immune system. Here we show that administration of a cocktail of HIV-1-specific monoclonal antibodies, as well as the single glycan-dependent monoclonal antibody PGT121, resulted in a rapid and precipitous decline of plasma viraemia to undetectable levels in rhesus monkeys chronically infected with the pathogenic simian-human immunodeficiency virus SHIV-SF162P3. A single monoclonal antibody infusion afforded up to a 3.1 log decline of plasma viral RNA in 7 days and also reduced proviral DNA in peripheral blood, gastrointestinal mucosa and lymph nodes without the development of viral resistance. Moreover, after monoclonal antibody administration, host Gag-specific T-lymphocyte responses showed improved functionality. Virus rebounded in most animals after a median of 56 days when serum monoclonal antibody titres had declined to undetectable levels, although, notably, a subset of animals maintained long-term virological control in the absence of further monoclonal antibody infusions. These data demonstrate a profound therapeutic effect of potent neutralizing HIV-1-specific monoclonal antibodies in SHIV-infected rhesus monkeys as well as an impact on host immune responses. Our findings strongly encourage the investigation of monoclonal antibody therapy for HIV-1 in humans.

Optimal Therapies for Newly Diagnosed Elderly Patients with Glioblastoma.

OPINION STATEMENT: Newly diagnosed elderly patients (age > 65-70 years) with glioblastoma should be treated with a patient-centred approach by a multi-disciplinary team. Chronological age alone should not be considered as a contraindication to treatment with maximal safe surgical resection. A 3-week course of adjuvant radiation and chemotherapy is appropriate in selected elderly patients with favourable Karnofsky performance status (KPS) who cannot tolerate a longer 6-week course of fractionated radiotherapy. The presence or absence of 06-methylguanine-DNA methyltransferase (MGMT) promoter methylation can be used to guide clinical decision-making as both prognostic and predictive biomarkers. This review provides an update and summary of the available evidence for treating newly diagnosed elderly patients with glioblastoma.

Thrombosis in brain tumors.

Venous thromboembolism (VTE) is common in patients with brain tumors, occurring in up to 30% of patients with high-grade glioma and up to 20% of those with brain metastasis and primary central nervous system (CNS) lymphoma. The risk is correlated with higher grade malignancies and is directly associated with the production of the potent procoagulant, tissue factor (TF). Upregulation of TF influences both the coagulation pathway and oncogenic signaling mechanisms important for cancer progression. The risk of intracranial hemorrhage with the use of anticoagulants complicates the management of VTE in patients with brain tumor. We discuss the recommended anticoagulants used for initial and long-term treatment of established VTE, including unfractionated heparin, low-molecular-weight heparin (LMWH), and warfarin. Therapeutic anticoagulation, particularly LMWH followed by secondary prophylaxis, is generally safe and effective in the treatment of VTE, including patients on antiangiogenic agents. Anticoagulation also reduces the risk of VTE during the perioperative period. However, despite the high risk of VTE throughout the course of disease, present data do not support routine thromboprophylaxis in brain tumor patients. Further investigation regarding the mechanisms underlying the hypercoagulable state of patients with brain tumors and the potential role of the factors and products of thrombogenesis as biomarkers for risk stratification will be useful in identification and management of patients at risk of developing VTE. Novel oral anticoagulants that directly inhibit thrombin such as dabigatran or factor Xa, including rivaroxaban and apixaban have several potential advantages; however, due to limited data in the cancer population, the use of these newer oral anticoagulants is not currently recommended for patients with malignancy and VTE. Recent studies have explored the role of anticoagulants as anticancer agents, which may contribute to cancer treatment in the future.

No benefit from TMZ treatment in GB with truly unmethylated MGMT promoter: Reanalysis of the CE.6 and the pooled Nordic/NOA-08 trials in elderly GB patients.

BACKGROUND: The treatment of elderly/ frail patients with glioblastoma is a balance between avoiding undue toxicity, while not withholding effective treatment. It remains debated, whether these patients should receive combined chemo-radiotherapy with temozolomide (RT/TMZ➜TMZ) regardless of the O6-methylguanine DNA methyltransferase gene promoter (MGMTp) methylation status. MGMT is a well-known resistance factor blunting the treatment effect of TMZ, by repairing the most genotoxic lesion. Epigenetic silencing of the MGMTp sensitizes glioblastoma to TMZ. For risk adapted treatment, it is of utmost importance to accurately identify patients, who will not benefit from TMZ treatment. METHODS: Here, we present a reanalysis of the clinical trials CE.6 and the pooled NOA-08 and Nordic trials in elderly glioblastoma patients that compared RT to RT/TMZ➜TMZ, or RT to TMZ, respectively. For 687 patients with available MGMTp methylation data, we applied a cutoff discerning truly unmethylated glioblastoma, established in a pooled analysis of four clinical trials for glioblastoma, with RT/TMZ➜TMZ treatment, using the same quantitative methylation specific MGMTp PCR assay. RESULTS: When applying this restricted cutoff to the elderly patient population, we confirmed that glioblastoma with truly unmethylated MGMTp derived no benefit from TMZ treatment. In the Nordic/NOA-08 trials RT was better than TMZ, suggesting little or no benefit from TMZ. CONCLUSION: For evidence-based treatment of glioblastoma patients validated MGMTp methylation assays should be used that accurately identify truly unmethylated patients. Respective stratified management of patients will reduce toxicity without compromising outcome and allow testing of more promising treatment options.

Lymph-node-targeted, mKRAS-specific amphiphile vaccine in pancreatic and colorectal cancer: the phase 1 AMPLIFY-201 trial.

Pancreatic and colorectal cancers are often KRAS mutated and are incurable when tumor DNA or protein persists or recurs after curative intent therapy. Cancer vaccine ELI-002 2P enhances lymph node delivery and immune response using amphiphile (Amph) modification of G12D and G12R mutant KRAS (mKRAS) peptides (Amph-Peptides-2P) together with CpG oligonucleotide adjuvant (Amph-CpG-7909). We treated 25 patients (20 pancreatic and five colorectal) who were positive for minimal residual mKRAS disease (ctDNA and/or serum tumor antigen) after locoregional treatment in a phase 1 study of fixed-dose Amph-Peptides-2P and ascending-dose Amph-CpG-7909; study enrollment is complete with patient follow-up ongoing. Primary endpoints included safety and recommended phase 2 dose (RP2D). The secondary endpoint was tumor biomarker response (longitudinal ctDNA or tumor antigen), with exploratory endpoints including immunogenicity and relapse-free survival (RFS). No dose-limiting toxicities were observed, and the RP2D was 10.0 mg of Amph-CpG-7909. Direct ex vivo mKRAS-specific T cell responses were observed in 21 of 25 patients (84%; 59% both CD4+ and CD8+); tumor biomarker responses were observed in 21 of 25 patients (84%); biomarker clearance was observed in six of 25 patients (24%; three pancreatic and three colorectal); and the median RFS was 16.33 months. Efficacy correlated with T cell responses above or below the median fold increase over baseline (12.75-fold): median tumor biomarker reduction was -76.0% versus -10.2% (P < 0.0014), and the median RFS was not reached versus 4.01 months (hazard ratio = 0.14; P = 0.0167). ELI-002 2P was safe and induced considerable T cell responses in patients with immunotherapy-recalcitrant KRAS-mutated tumors. ClinicalTrials.gov identifier: NCT04853017 .

High cell-free virus load and robust autologous humoral immune responses in breast milk of simian immunodeficiency virus-infected african green monkeys.

The design of immunologic interventions to prevent postnatal transmission of human immunodeficiency virus (HIV) will require identification of protective immune responses in this setting. Simian immunodeficiency virus (SIV)-infected rhesus monkeys (RMs), a species that develops an AIDS-like illness following experimental infection, transmit the virus at a high rate during breastfeeding. In contrast, postnatal transmission of SIV occurs rarely or not at all in natural, asymptomatic primate hosts of SIV. These contrasting transmission patterns provide a unique opportunity to study mechanisms that evolved to protect suckling infants from SIV infection. We compared the virologic and immunologic properties of milk of SIV-infected and uninfected natural hosts of SIV, African green monkeys (AGMs), to that of RMs. Interestingly, despite a low number of milk CD4(+) T lymphocytes in uninfected AGMs, milk virus RNA load in SIV-infected AGMs was comparable to that of SIV-infected RMs and that in AGM plasma. This observation is in contrast to the relatively low virus load in milk compared to that in plasma of SIV-infected RMs and HIV-infected women. Milk of SIV-infected AGMs also displayed robust virus-specific cellular immune responses. Importantly, an autologous challenge virus-specific neutralization response was detected in milk of five of six SIV-infected AGMs that was comparable in magnitude to that in plasma. In contrast, autologous challenge virus neutralization was not detectable in milk of SIV-infected RMs. The autologous virus-specific adaptive immune responses in breast milk of AGMs may contribute to impedance of virus transmission in the infant oral/gastrointestinal tract and the rarity of postnatal virus transmission in natural hosts of SIV.

Updates in IDH-Wildtype Glioblastoma.

Glioblastoma is the most aggressive primary brain tumor with a poor prognosis. The 2021 WHO CNS5 classification has further stressed the importance of molecular signatures in diagnosis although therapeutic breakthroughs are still lacking. In this review article, updates on the current and novel therapies in IDH-wildtype GBM will be discussed.

Glioblastoma: patterns of recurrence and efficacy of salvage treatments.

BACKGROUND: It is controversial if distant recurrence of glioblastoma is more common after temozolomide (TMZ) concurrent with radiotherapy (RT). Optimal therapy for patients with recurrent disease after RT/TMZ is unclear. Our purpose was to evaluate recurrence patterns in glioblastoma and the effect of treatment at recurrence upon survival. METHODS: We performed a retrospective review of 67 patients with newly diagnosed glioblastoma treated with RT/TMZ between 2003-2007. Statistical analyses included Kaplan-Meier method for survival, and multivariate Cox proportional hazards model for the effect of salvage treatment on survival. RESULTS: 58 patients (86.6%) recurred locally; 9 patients (13.4%) had a distant non-contiguous focus of new disease. Median survival(MS) was 17 months; median time-to-progression(TTP) 6.8 months. The local and distant groups had comparable prognostic factors. There was no difference in MS(p=0.35) or TTP(p=0.95) by location of recurrence. At relapse, 26 patients(38.8%) received continuous, dose-intense TMZ, 24(35.8%) other therapy(4.5% RT; 20.9% lomustine+/-procarbazine; 4.5% etoposide; 1.5% conventional TMZ; 4.5% TMZ then lomustine), and 17(25.4%) were untreated. Dose-intense TMZ was associated with prolonged MS compared to all other patients(21.5 months vs. 12.4 months, p=0.019, HR=3.86, 95%CI: 1.81-8.22) and similar to MS with other chemotherapy regimens(18.8 months, p=0.40, HR=1.30, 95% CI: 0.65-2.61). CONCLUSION: The pattern of recurrence of glioblastoma treated with RT/TMZ was predominantly local. Second-line treatment with continuous dose-intense TMZ may prolong survival in patients with recurrent glioblastoma. Overall survival is similar to other conventional salvage regimens; however TMZ may be better tolerated. This study is limited by its retrospective nature and potential selection bias. Prospective controlled studies are needed.

Update on the management of elderly patients with glioblastoma: a narrative review.

Glioblastoma in the elderly (>65 years of age) is associated with shorter overall survival (OS) than in younger patients. Best practice recommendations for elderly patients, especially those with borderline or poor performance status, remain a subject of debate amongst clinicians despite recent randomized trials. This review provides an updated evidence-based summary to inform the modern management of elderly patients with glioblastoma. Based on evidence from the CE.6 randomized controlled trial, hypofractionated radiation therapy administered over a three-week course (40 Gy in 15 fractions) concomitantly with temozolomide (TMZ) followed by adjuvant TMZ has been found to be superior to radiation therapy alone with mean OS of 9.3 vs. 7.6 months and progression-free survival (PFS) of 5.3 vs. 3.9 months. This regimen should be offered to newly-diagnosed elderly patients with glioblastoma with preserved functional status, and was not associated with a negative impact on health-related quality of life (QOL). Management of elderly patients with glioblastoma can be challenging and requires a patient-centered strategy. Personalized decisions accounting for clinical, psychosocial, molecular and treatment factors are critical for realistic decision making. The importance of discussing goals-of-care with patients and their caregivers early in the disease trajectory, and establishing capacity for decision-making and advanced care planning, is also reviewed.

Anticoagulation of malignant glioma patients in the era of novel antiangiogenic agents.

PURPOSE OF REVIEW: Venous thromboembolism (VTE) is common in patients with brain tumors. Anticoagulant therapy is feared due to the risk of bleeding, especially intracranial hemorrhage. Emerging treatment approaches targeting angiogenesis, may increase the risk of both thrombosis and bleeding. Recent advances in the cause, prevention, and treatment of VTE in brain tumor patients in the era of antiangiogenic therapy are reviewed. RECENT FINDINGS: About 20-30% of malignant glioma patients develop clinically significant thromboembolism; however, a recent randomized trial suggested increased intracranial bleeding with the use of prophylactic anticoagulation. Antiangiogenic therapies, especially those targeting vascular endothelial growth factor or its receptor, may increase the risk of thrombosis. New data regarding the safety of anticoagulation concurrent with bevacizumab have emerged. SUMMARY: VTE is common perioperatively and throughout the course of brain tumor therapy. Therapeutic anticoagulation followed by secondary anticoagulant thromboprophylaxis is indicated in most patients with DVT or pulmonary embolism, including patients receiving antiangiogenic agents. The role of primary antithrombotic prophylaxis remains unclear.

A citywide prehospital protocol increases access to stroke thrombolysis in Toronto.

BACKGROUND AND PURPOSE: Intravenous tissue plasminogen activator for ischemic stroke is approved for eligible patients who can be treated within a 3-hour window, but treatment rates remain disappointingly low, often <5%. To improve rapid access to stroke thrombolysis in Toronto, Canada, a citywide prehospital acute stroke activation protocol was implemented by the provincial government to transport acute stroke patients directly to one of 3 regional stroke centers, bypassing local hospitals. This comprised a paramedic screening tool, ambulance destination decision rule, and formal memorandum of understanding of system stakeholders. This report describes the initial impact of the activation protocol at our regional stroke center. METHODS: We compared consecutive patients with stroke arriving to our stroke center during the first 4 months of this new triage protocol (February 14 to June 14, 2005) versus the same 4-month period in 2004. RESULTS: The protocol resulted in an immediate doubling in the number of patients with acute stroke arriving to our regional stroke center within 2.5 hours of symptom onset. We observed a 4-fold increase in patients who were eligible for and treated with tissue plasminogen activator. The tissue plasminogen activator treatment rate for ischemic stroke patients increased from 9.5% to 23.4% (P=0.01), and one in 2 patients with ischemic stroke arriving within 2.5 hours received thrombolysis during this period (one in 5 of patients with ischemic stroke overall). The median onset-to-needle time for tissue plasminogen activator-treated patients was significantly reduced. Many implementation challenges were identified and addressed. CONCLUSIONS: This prehospital triage was immediately successful in improving tissue plasminogen activator access for patients with ischemic stroke, enabling our center to achieve one of the highest tissue plasminogen activator treatment rates in North America and underscoring the need for coordinated systems of acute stroke care. Sustainability of such an initiative will be dependent on interdisciplinary teamwork, ongoing paramedic training, adequate hospital staffing, bed availability, and repatriation agreements with community hospitals.

Procarbazine, CCNU and vincristine (PCV) versus temozolomide chemotherapy for patients with low-grade glioma: a systematic review.

Low-grade gliomas (LGG) encompass a heterogeneous group of tumors that are clinically, histologically and molecularly diverse. Treatment decisions for patients with LGG are directed toward improving upon the natural history while limiting treatment-associated toxiceffects. Recent evidence has documented a utility for adjuvant chemotherapy with procarbazine, CCNU (lomustine), and vincristine (PCV) or temozolomide (TMZ). We sought to determine the comparative utility of PCV and TMZ for patients with LGG, particularly in context of molecular subtype. A literature search of PubMed was conducted to identify studies reporting patient response to PCV, TMZ, or a combination of chemotherapy and radiation therapy (RT). Eligibility criteria included patients 16 years of age and older, notation of LGG subtype, and report of progression-free survival (PFS), overall survival (OS), and treatment course. Level I, II, and III data were included. Adjuvant therapy with PCV resulted in prolonged PFS and OS in patients with newly diagnosed high-risk LGG. This benefit was accrued most significantly by patients with tumors harboring 1p/19q codeletion and IDH1 mutation. Adjuvant therapy with temozolomide was associated with lower toxicity than therapy with PCV. In patients with LGG with an unfavorable natural history, such as with intact 1p/19q and wild-type IDH1, RT/TMZ plus adjuvant TMZ may be the best option. Patients with biologically favorable high-risk LGG are likely to derive the most benefit from RT and adjuvant PCV.

Hospitalizations in elderly glioblastoma patients.

BACKGROUND: Elderly glioblastoma (GB) patients are at risk of hospitalizations due to the morbidity of the disease and possible treatment toxicity. METHODS: In this observational cohort study, 255 newly diagnosed GB patients age 65 years and older were included. Survival, emergency room visits and admissions to an acute care hospital were determined. Mean and median total health care costs were calculated. Risk factors for Emergency room visits and acute care hospital admissions were determined. RESULTS: Median overall survival was 6 months. The majority of patients (68%) had at least one visit to the emergency department and 77% had at least one admission to acute care. The mean and median total costs (hospital, ambulatory, physician billing, other health care costs) per patient were $162,479.78 (CAN) and $125,511.00 (CAN), respectively. Treatment with radiation or treatment with radio-chemotherapy was associated with a relative risk (RR) of 2.31 (95% CI: 1.44-3.7; P=0.0005) and 2.19 (95% CI: 1.28-3.74; P=0.004), respectively for emergency department visits as compared to patients who were managed with comfort measures only. Patients with a baseline ECOG 0 had a RR of 1.71 (95% CI: 1.06-2.77; P=0.0289) and patients with baseline ECOG 1 had a RR of 1.49 (0.98-2.26; P=0.0623) for hospital admission as compared to patients with ECOG 4. CONCLUSIONS: A large proportion of elderly GB patients (particularly those with good baseline performance status who underwent active treatment) presented to the emergency department and had at least one admission to acute care.