ACTION: a randomized phase 3 study of ONC201 (dordaviprone) in patients with newly diagnosed H3 K27M-mutant diffuse glioma

BACKGROUND

H3 K27M-mutant diffuse glioma primarily affects children and young adults, is associated with a poor prognosis, and no effective systemic therapy is currently available. ONC201 (dordaviprone) has previously demonstrated efficacy in patients with recurrent disease. This phase 3 trial evaluates ONC201 in patients with newly diagnosed H3 K27M-mutant glioma.

METHODS

ACTION (NCT05580562) is a randomized, double-blind, placebo-controlled, parallel-group, international phase 3 study of ONC201 in newly diagnosed H3 K27M-mutant diffuse glioma. Patients who have completed standard frontline radiotherapy are randomized 1:1:1 to receive placebo, once-weekly dordaviprone, or twice-weekly dordaviprone on 2 consecutive days. Primary efficacy endpoints are overall survival (OS) and progression-free survival (PFS); PFS is assessed by response assessment in neuro-oncology high-grade glioma criteria (RANO-HGG) by blind independent central review. Secondary objectives include safety, additional efficacy endpoints, clinical benefit, and quality of life. Eligible patients have histologically confirmed H3 K27M-mutant diffuse glioma, a Karnofsky/Lansky performance status ≥70, and completed first-line radiotherapy. Eligibility is not restricted by age; however, patients must be ≥10 kg at time of randomization. Patients with a primary spinal tumor, diffuse intrinsic pontine glioma, leptomeningeal disease, or cerebrospinal fluid dissemination are not eligible. ACTION is currently enrolling in multiple international sites.

Deep-learning-based reconstruction of undersampled MRI to reduce scan times: a multicentre, retrospective, cohort study

BACKGROUND

The extended acquisition times required for MRI limit its availability in resource-constrained settings. Consequently, accelerating MRI by undersampling k-space data, which is necessary to reconstruct an image, has been a long-standing but important challenge. We aimed to develop a deep convolutional neural network (dCNN) optimisation method for MRI reconstruction and to reduce scan times and evaluate its effect on image quality and accuracy of oncological imaging biomarkers.

METHODS

In this multicentre, retrospective, cohort study, MRI data from patients with glioblastoma treated at Heidelberg University Hospital (775 patients and 775 examinations) and from the phase 2 CORE trial (260 patients, 1083 examinations, and 58 institutions) and the phase 3 CENTRIC trial (505 patients, 3147 examinations, and 139 institutions) were used to develop, train, and test dCNN for reconstructing MRI from highly undersampled single-coil k-space data with various acceleration rates (R=2, 4, 6, 8, 10, and 15). Independent testing was performed with MRIs from the phase 2/3 EORTC-26101 trial (528 patients with glioblastoma, 1974 examinations, and 32 institutions). The similarity between undersampled dCNN-reconstructed and original MRIs was quantified with various image quality metrics, including structural similarity index measure (SSIM) and the accuracy of undersampled dCNN-reconstructed MRI on downstream radiological assessment of imaging biomarkers in oncology (automated artificial intelligence-based quantification of tumour burden and treatment response) was performed in the EORTC-26101 test dataset. The public NYU Langone Health fastMRI brain test dataset (558 patients and 558 examinations) was used to validate the generalisability and robustness of the dCNN for reconstructing MRIs from available multi-coil (parallel imaging) k-space data.

FINDINGS

In the EORTC-26101 test dataset, the median SSIM of undersampled dCNN-reconstructed MRI ranged from 0·88 to 0·99 across different acceleration rates, with 0·92 (95% CI 0·92-0·93) for 10-times acceleration (R=10). The 10-times undersampled dCNN-reconstructed MRI yielded excellent agreement with original MRI when assessing volumes of contrast-enhancing tumour (median DICE for spatial agreement of 0·89 [95% CI 0·88 to 0·89]; median volume difference of 0·01 cm3 [95% CI 0·00 to 0·03] equalling 0·21%; p=0·0036 for equivalence) or non-enhancing tumour or oedema (median DICE of 0·94 [95% CI 0·94 to 0·95]; median volume difference of -0·79 cm3 [95% CI -0·87 to -0·72] equalling -1·77%; p=0·023 for equivalence) in the EORTC-26101 test dataset. Automated volumetric tumour response assessment in the EORTC-26101 test dataset yielded an identical median time to progression of 4·27 months (95% CI 4·14 to 4·57) when using 10-times-undersampled dCNN-reconstructed or original MRI (log-rank p=0·80) and agreement in the time to progression in 374 (95·2%) of 393 patients with data. The dCNN generalised well to the fastMRI brain dataset, with significant improvements in the median SSIM when using multi-coil compared with single-coil k-space data (p<0·0001).

INTERPRETATION

Deep-learning-based reconstruction of undersampled MRI allows for a substantial reduction of scan times, with a 10-times acceleration demonstrating excellent image quality while preserving the accuracy of derived imaging biomarkers for the assessment of oncological treatment response. Our developments are available as open source software and hold considerable promise for increasing the accessibility to MRI, pending further prospective validation.

FUNDING

Deutsche Forschungsgemeinschaft (German Research Foundation) and an Else Kröner Clinician Scientist Endowed Professorship by the Else Kröner Fresenius Foundation.

Brain tumors in United States military veterans

BACKGROUND

Comprehensive analysis of brain tumor incidence and survival in the Veteran population has been lacking.

METHODS

Veteran data were obtained from the Veterans Health Administration (VHA) Medical Centers via VHA Corporate Data Warehouse. Brain tumor statistics on the overall US population were generated from the Central Brain Tumor Registry of the US data. Cases were individuals (≥18 years) with a primary brain tumor, diagnosed between 2004 and 2018. The average annual age-adjusted incidence rates (AAIR) and 95% confidence intervals were estimated per 100 000 population and Kaplan-Meier survival curves evaluated overall survival outcomes among Veterans.

RESULTS

The Veteran population was primarily white (78%), male (93%), and between 60 and 64 years old (18%). Individuals with a primary brain tumor in the general US population were mainly female (59%) and between 18 and 49 years old (28%). The overall AAIR of primary brain tumors from 2004 to 2018 within the Veterans Affairs cancer registry was 11.6. Nonmalignant tumors were more common than malignant tumors (AAIR:7.19 vs 4.42). The most diagnosed tumors in Veterans were nonmalignant pituitary tumors (AAIR:2.96), nonmalignant meningioma (AAIR:2.62), and glioblastoma (AAIR:1.96). In the Veteran population, survival outcomes became worse with age and were lowest among individuals diagnosed with glioblastoma.

CONCLUSIONS

Differences between Veteran and US populations can be broadly attributed to demographic composition differences of these groups. Prior to this, there have been no reports on national-level incidence rates and survival outcomes for Veterans. These data provide vital information that can drive efforts to understand disease burden and improve outcomes for individuals with primary brain tumors.

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.).

Association of antidepressant drug use with outcome of patients with glioblastoma

Depressive symptoms are common among patients with glioblastoma, but patients are often not treated with antidepressants. There is only limited evidence on the association of antidepressant drug use with survival in glioblastoma. We performed a pooled analysis of patients treated within the CENTRIC, CORE, AVAglio and ACT-IV trials to explore the relation of antidepressant drug use with progression-free (PFS) and overall survival (OS) at baseline, at the start of maintenance therapy and at the start of maintenance cycle 4. We further assessed the association of antidepressant drugs with seizure, cognition, fatigue and a diagnosis of depression. Among more than 1700 patients, we found no significant association between the use of antidepressants at baseline or at the start of maintenance therapy and PFS or OS. However, we found OS, but not PFS, to be significantly worse in patients using antidepressants at the start of maintenance cycle 4. After adjustment for antiepileptic drug use and despite showing a trend for increased risk, seizures were not significantly associated with antidepressant drug use, nor was there a change in mini mental state examination (MMSE) scores or fatigue by antidepressant drug use at baseline. However, there was a significant positive association between antidepressant use at the start of maintenance treatment and fatigue during maintenance treatment. The association of antidepressant use at the start of maintenance cycle 4 with inferior OS of glioblastoma patients requires independent confirmation and further study. Further prospective trials should evaluate efficacy, side effects and associations with outcome of antidepressants in glioblastoma.

Multiplatform molecular analyses refine classification of gliomas arising in patients with neurofibromatosis type 1

Gliomas arising in the setting of neurofibromatosis type 1 (NF1) are heterogeneous, occurring from childhood through adulthood, can be histologically low-grade or high-grade, and follow an indolent or aggressive clinical course. Comprehensive profiling of genetic alterations beyond NF1 inactivation and epigenetic classification of these tumors remain limited. Through next-generation sequencing, copy number analysis, and DNA methylation profiling of gliomas from 47 NF1 patients, we identified 2 molecular subgroups of NF1-associated gliomas. The first harbored biallelic NF1 inactivation only, occurred primarily during childhood, followed a more indolent clinical course, and had a unique epigenetic signature for which we propose the terminology "pilocytic astrocytoma, arising in the setting of NF1". The second subgroup harbored additional oncogenic alterations including CDKN2A homozygous deletion and ATRX mutation, occurred primarily during adulthood, followed a more aggressive clinical course, and was epigenetically diverse, with most tumors aligning with either high-grade astrocytoma with piloid features or various subclasses of IDH-wildtype glioblastoma. Several patients were treated with small molecule MEK inhibitors that resulted in stable disease or tumor regression when used as a single agent, but only in the context of those tumors with NF1 inactivation lacking additional oncogenic alterations. Together, these findings highlight recurrently altered pathways in NF1-associated gliomas and help inform targeted therapeutic strategies for this patient population.

P09.03.A Associations of levetiracetam use with the safety and tolerability of chemoradiotherapy for patients with newly diagnosed glioblastoma

Background

Levetiracetam (LEV) is one of the most frequently used antiepileptic drugs (AED) for brain tumor patients with seizures. We hypothesized that toxicity of LEV and temozolomide-based chemoradiotherapy may overlap.

Patients and Methods

In a retrospective analysis of individual patient data using a pooled cohort of patients with newly diagnosed glioblastoma included in clinical trials prior to chemoradiotherapy (CENTRIC, CORE, AVAglio) or prior to maintenance therapy (ACT-IV), we tested associations of hematologic toxicity, nausea or emesis, fatigue, and psychiatric adverse events during concomitant and maintenance treatment with the use of LEV alone or with other AED versus other AED alone or in combination versus no AED use at the start of chemoradiotherapy and of maintenance treatment.

Results

Of 1681 and 2020 patients who started concomitant chemoradiotherapy and maintenance temozolomide, respectively, 473 and 714 patients (28.1% and 35.3%) were treated with a LEV-containing regimen, 538 and 475 patients (32.0% and 23.5%) with other AED, and 670 and 831 patients (39.9% and 41.1%) had no AED. LEV was associated with higher risk of psychiatric adverse events during concomitant treatment in univariable and multivariable analyses (RR 1.86 and 1.88, p&lt;0.001) while there were no associations with hematologic toxicity, nausea or emesis, or fatigue. LEV was associated with reduced risk of nausea or emesis during maintenance treatment in multivariable analysis (HR=0.80, p=0.017) while there were no associations with hematologic toxicity, fatigue, or psychiatric adverse events.

Conclusion

Any association of psychiatric adverse events with LEV did not persist beyond the concomitant treatment phase. Antiemetic properties of LEV may be beneficial during the maintenance temozolomide.

Prognostic significance of therapy-induced myelosuppression in newly diagnosed glioblastoma

BACKGROUND

Myelosuppression is the major toxicity encountered during temozolomide chemoradiotherapy for newly diagnosed glioblastoma.

METHODS

We assessed the association of myelosuppression (neutropenia, thrombocytopenia, anemia, and lymphopenia) during temozolomide chemoradiotherapy alone or in combination with experimental agents with progression-free survival (PFS) or overall survival (OS) in 2073 patients with newly diagnosed glioblastoma enrolled into five clinical trials: CENTRIC, CORE, EORTC 26082, AVAglio, and EORTC 26981. A landmark Cox model was used. For each primary association analysis, a significance level of 1.7% was used.

RESULTS

Lower neutrophil counts at baseline were associated with better PFS (P = .011) and OS (P < .001), independently of steroid intake. Females experienced uniformly more myelotoxicity than males. Lymphopenia during concomitant chemoradiotherapy was associated with OS (P = .009): low-grade (1-2) lymphopenia might be associated with superior OS (HR 0.78, 98.3% CI 0.58-1.06), whereas high-grade (3-4) lymphopenia might be associated with inferior OS (HR 1.08, 98.3% CI 0.75-1.54). There were no associations of altered hematological parameters during concomitant chemoradiotherapy with PFS. During maintenance chemoradiotherapy, no significant association was found between any parameter of myelosuppression and PFS or OS, although exploratory analysis at 5% significance level indicated that either mild-to-moderate (HR 0.76, 95% CI 0.62-0.93) or high-grade lymphopenia (HR 0.65, 95% CI 0.46-0.92) was associated with superior OS (P = .013), but not PFS.

CONCLUSIONS

The association of higher neutrophil counts at baseline with inferior PFS and OS requires further prospective evaluation. The link of therapy-induced lymphopenia to better outcome may guide the design for immunotherapy trials in newly diagnosed glioblastoma.

Surveillance imaging frequency in adult patients with lower-grade (WHO Grade 2 and 3) gliomas

With improved outcome following aggressive treatment in patients with grade 2 and 3 IDH-mutant (IDHmt), 1p/19q codeleted oligodendroglioma and IDHmt, non-codeleted astrocytoma, prolonged surveillance is desirable for early detection of tumor growth and malignant transformation. Current National Comprehensive Cancer Network (NCCN) guidelines provide imaging follow-up recommendations based on molecular classification of lower-grade gliomas, although individualized imaging guidelines based on treatments received and after tumor recurrence are not clearly specified. Other available guidelines have yet to incorporate the molecular biomarkers that inform the WHO classification of gliomas, and in some cases do not adequately consider current knowledge on IDHmt glioma growth rate and recurrence patterns. Moreover, these guidelines also do not provide specific recommendations for concerning clinical symptoms or radiographic findings warranting imaging studies out of prespecified intervals. Focusing on molecularly defined grade 2 and 3 IDHmt astrocytomas and oligodendrogliomas, we review current knowledge of tumor growth rates and time to tumor progression for each tumor type and propose a range of recommended MRI surveillance intervals for both the newly diagnosed and recurrent tumor setting. Additionally, we summarize situations in which imaging is advisable outside of these intervals.

Associations of levetiracetam use with the safety and tolerability profile of chemoradiotherapy for patients with newly diagnosed glioblastoma

Background

Levetiracetam (LEV) is one of the most frequently used antiepileptic drugs (AED) for brain tumor patients with seizures. We hypothesized that toxicity of LEV and temozolomide-based chemoradiotherapy may overlap.

Methods

Using a pooled cohort of patients with newly diagnosed glioblastoma included in clinical trials prior to chemoradiotherapy (CENTRIC, CORE, AVAglio) or prior to maintenance therapy (ACT-IV), we tested associations of hematologic toxicity, nausea or emesis, fatigue, and psychiatric adverse events during concomitant and maintenance treatment with the use of LEV alone or with other AED versus other AED alone or in combination versus no AED use at the start of chemoradiotherapy and of maintenance treatment.

Results

Of 1681 and 2020 patients who started concomitant chemoradiotherapy and maintenance temozolomide, respectively, 473 and 714 patients (28.1% and 35.3%) were treated with a LEV-containing regimen, 538 and 475 patients (32.0% and 23.5%) with other AED, and 670 and 831 patients (39.9% and 41.1%) had no AED. LEV was associated with higher risk of psychiatric adverse events during concomitant treatment in univariable and multivariable analyses (RR 1.86 and 1.88, P &lt; .001) while there were no associations with hematologic toxicity, nausea or emesis, or fatigue. LEV was associated with reduced risk of nausea or emesis during maintenance treatment in multivariable analysis (HR = 0.80, P = .017) while there were no associations with hematologic toxicity, fatigue, or psychiatric adverse events.

Conclusions

LEV is not associated with reduced tolerability of chemoradiotherapy in patients with glioblastoma regarding hematologic toxicity and fatigue. Antiemetic properties of LEV may be beneficial during maintenance temozolomide.

Deep-learning-based synthesis of post-contrast T1-weighted MRI for tumour response assessment in neuro-oncology: a multicentre, retrospective cohort study

BACKGROUND

Gadolinium-based contrast agents (GBCAs) are widely used to enhance tissue contrast during MRI scans and play a crucial role in the management of patients with cancer. However, studies have shown gadolinium deposition in the brain after repeated GBCA administration with yet unknown clinical significance. We aimed to assess the feasibility and diagnostic value of synthetic post-contrast T1-weighted MRI generated from pre-contrast MRI sequences through deep convolutional neural networks (dCNN) for tumour response assessment in neuro-oncology.

METHODS

In this multicentre, retrospective cohort study, we used MRI examinations to train and validate a dCNN for synthesising post-contrast T1-weighted sequences from pre-contrast T1-weighted, T2-weighted, and fluid-attenuated inversion recovery sequences. We used MRI scans with availability of these sequences from 775 patients with glioblastoma treated at Heidelberg University Hospital, Heidelberg, Germany (775 MRI examinations); 260 patients who participated in the phase 2 CORE trial (1083 MRI examinations, 59 institutions); and 505 patients who participated in the phase 3 CENTRIC trial (3147 MRI examinations, 149 institutions). Separate training runs to rank the importance of individual sequences and (for a subset) diffusion-weighted imaging were conducted. Independent testing was performed on MRI data from the phase 2 and phase 3 EORTC-26101 trial (521 patients, 1924 MRI examinations, 32 institutions). The similarity between synthetic and true contrast enhancement on post-contrast T1-weighted MRI was quantified using the structural similarity index measure (SSIM). Automated tumour segmentation and volumetric tumour response assessment based on synthetic versus true post-contrast T1-weighted sequences was performed in the EORTC-26101 trial and agreement was assessed with Kaplan-Meier plots.

FINDINGS

The median SSIM score for predicting contrast enhancement on synthetic post-contrast T1-weighted sequences in the EORTC-26101 test set was 0·818 (95% CI 0·817-0·820). Segmentation of the contrast-enhancing tumour from synthetic post-contrast T1-weighted sequences yielded a median tumour volume of 6·31 cm³ (5·60 to 7·14), thereby underestimating the true tumour volume by a median of -0·48 cm³ (-0·37 to -0·76) with the concordance correlation coefficient suggesting a strong linear association between tumour volumes derived from synthetic versus true post-contrast T1-weighted sequences (0·782, 0·751-0·807, p<0·0001). Volumetric tumour response assessment in the EORTC-26101 trial showed a median time to progression of 4·2 months (95% CI 4·1-5·2) with synthetic post-contrast T1-weighted and 4·3 months (4·1-5·5) with true post-contrast T1-weighted sequences (p=0·33). The strength of the association between the time to progression as a surrogate endpoint for predicting the patients' overall survival in the EORTC-26101 cohort was similar when derived from synthetic post-contrast T1-weighted sequences (hazard ratio of 1·749, 95% CI 1·282-2·387, p=0·0004) and model C-index (0·667, 0·622-0·708) versus true post-contrast T1-weighted MRI (1·799, 95% CI 1·314-2·464, p=0·0003) and model C-index (0·673, 95% CI 0·626-0·711).

INTERPRETATION

Generating synthetic post-contrast T1-weighted MRI from pre-contrast MRI using dCNN is feasible and quantification of the contrast-enhancing tumour burden from synthetic post-contrast T1-weighted MRI allows assessment of the patient's response to treatment with no significant difference by comparison with true post-contrast T1-weighted sequences with administration of GBCAs. This finding could guide the application of dCNN in radiology to potentially reduce the necessity of GBCA administration.

FUNDING

Deutsche Forschungsgemeinschaft.

Temporal muscle thickness as a prognostic marker in newly diagnosed glioblastoma patients: translational imaging analysis of the CENTRIC EORTC 26071-22072 and CORE trials

PURPOSE

To investigate the prognostic relevance of temporal muscle thickness (TMT) as a surrogate parameter of skeletal muscle status in patients with newly diagnosed glioblastoma.

METHODS

We assessed TMT in cranial magnetic resonance images (MRI) of 755 patients enrolled in the CENTRIC EORTC 26071-22072 study (n=508) and CORE study (n=247). We used predefined sex-specific TMT cutoff values to categorize "patients at risk of sarcopenia" and "patients with normal muscle status" at baseline. Furthermore, we categorized patients according to the extent of TMT loss over time. Associations with progression-free survival (PFS) and overall survival (OS) were evaluated using the Cox model adjusted for other exploratory variables.

RESULTS

Patients at risk of sarcopenia (CENTRIC; n=158/508, 31.1%; CORE; n=87/247, 35.2%) at baseline had significantly higher risk of progression and death than patients with normal muscle status in both study cohorts (CENTRIC: PFS=HR 0.16, 95% CI: 0.12, 0.21, p<0.001; OS=HR 0.341, 95% CI: 0.27, 0.44, p < 0.001; CORE: PFS=HR 0.29, 95% CI: 0.21, 0.39, p<0.001; OS=HR 0.365, 95% CI: 0.27, 0.49, p<0.001). Similar results were obtained in multivariate Cox models adjusted for other important prognostic parameters. The extent of TMT loss over time showed a significant inverse correlation with median OS times in patients at risk for sarcopenia (CENTRIC: p<0.001, CORE: p=0.005), but not in patients with normal baseline muscle mass (CENTRIC: p=0.538, CORE: p=0.28).

CONCLUSION

TMT identifies ambulatory patients with newly diagnosed glioblastoma at risk for progressive sarcopenia and adverse outcomes. Early intervention may prevent skeletal muscle loss and improve patient outcome.

OS05.3.A Temporal muscle thickness as surrogate parameter of sarcopenia in newly diagnosed glioblastoma patients:translational imaging analysis of the CENTRIC EORTC 26071-22072 and CORE trials

BACKGROUND

Temporal muscle thickness (TMT) was described as surrogate parameter of skeletal muscle mass. This study aimed to investigate the prognostic relevance of TMT in patients with newly diagnosed glioblastoma.

MATERIAL AND METHODS

TMT was assessed in cranial magnetic resonance images (MRI) of 755 pts enrolled in the CENTRIC EORTC 26071-22072 study (n=508) and CORE study (n=247). Predefined sex-specific TMT cutoff values were used to categorize “patients at risk of sarcopenia” and “patients with normal muscle status” at baseline. Furthermore, patients were categorized according to the extent of TMT loss over time. Cox models adjusted for other explanatory variables were used to evaluate the associations with progression-free survival (PFS) and overall survival (OS).

RESULTS

Overall, 510/755 (67.6%) patients were categorized as “at risk of sarcopenia” and 245/755 (32.4%) patients had normal muscle status at baseline. In both study cohorts patient at risk of sarcopenia at baseline had significantly higher risk of progression and death than patients with normal muscle status (CENTRIC: PFS = HR 0.16, 95% CI: 0.12, 0.21, p&lt;0.001; OS = HR 0.341, 95% CI: 0.27, 0.44, p &lt; 0.001; CORE: PFS = HR 0.29, 95% CI: 0.21, 0.39, p&lt;0.001; OS = HR 0.365, 95% CI: 0.27, 0.49, p&lt;0.001). In multivariate Cox models adjusted for other important prognostic parameters similar results were obtained. In patients at risk for sarcopenia the extent of TMT loss over time showed a significant inverse correlation with median OS times (CENTRIC: p &lt; 0.001, CORE: p = 0.005, log-rank test), but not in patients with normal baseline muscle mass in both study cohorts (CENTRIC: p = 0.538, CORE: p = 0.28, log-rank test).

CONCLUSION

TMT identifies patients with newly diagnosed glioblastoma at risk for progressive sarcopenia and adverse outcomes. Early intervention for muscle mass preservation including exercise and resistance training as well as nutritional support may prevent skeletal muscle loss and improve patient outcome in this group of patients.

Integrin αvβ3 Engagement Regulates Glucose Metabolism and Migration through Focal Adhesion Kinase (FAK) and Protein Arginine Methyltransferase 5 (PRMT5) in Glioblastoma Cells

Metabolic reprogramming promotes glioblastoma cell migration and invasion. Integrin αvβ3 is one of the major integrin family members in glioblastoma multiforme cell surface mediating interactions with extracellular matrix proteins that are important for glioblastoma progression. The role of αvβ3 integrin in regulating metabolic reprogramming and its mechanism of action have not been determined in glioblastoma cells. Integrin αvβ3 engagement with osteopontin promotes glucose uptake and aerobic glycolysis, while inhibiting mitochondrial oxidative phosphorylation. Blocking or downregulation of integrin αvβ3 inhibits glucose uptake and aerobic glycolysis and promotes mitochondrial oxidative phosphorylation, resulting in decreased migration and growth in glioblastoma cells. Pharmacological inhibition of focal adhesion kinase (FAK) or downregulation of protein arginine methyltransferase 5 (PRMT5) blocks metabolic shift toward glycolysis and inhibits glioblastoma cell migration and invasion. These results support that integrin αvβ3 and osteopontin engagement plays an important role in promoting the metabolic shift toward glycolysis and inhibiting mitochondria oxidative phosphorylation in glioblastoma cells. The metabolic shift in cell energy metabolism is coupled to changes in migration, invasion, and growth, which are mediated by downstream FAK and PRMT5 in glioblastoma cells.

Implementing a Clinic-Based Telehealth Support Service (FamilyStrong) for Family Caregivers of Individuals with Grade IV Brain Tumors

Background: Nearly 3 million U.S. family caregivers support someone with cancer. However, oncology clinic-based service lines that proactively screen, assess, and support cancer caregivers are nearly nonexistent. Objective: To examine first-year experiences of a nurse-led clinic-based telehealth support service (FamilyStrong) for family caregivers of patients with recently diagnosed grade IV brain tumors. Methods: This is a retrospective evaluation of operational outcomes from initial implementation of the FamilyStrong Service, developed in partnership with Caregiver and Bereavement Support Services at the University of Alabama at Birmingham (UAB) and the UAB Center for Palliative and Supportive Care. From August 2018 to December 2019, 53 family caregivers were proactively identified and enrolled by a palliative care nurse, working approximately one day/week, who performed monthly caregiver distress thermometer screenings by phone and provided emotional, educational, problem-solving, and referral support. Results: Enrolled family caregivers were a mean age of 53.5 years and mostly female (62.3%), full- or part-time employed (67.9%), and the patient's spouse/partner (79.3%). Caregivers provided support 6.7 days/week for 11.2 hours/day. The palliative care nurse performed 235 distress screenings and provided support that included 68 documented instances of emotional, problem-solving, and educational support, 41 nurse-facilitated communications with the neuro-oncology team about patient issues, and 24 referrals to UAB and community services (e.g., counseling). The most common problems caregivers wanted assistance with included: managing their relative's health condition and symptoms (51%), coordinating care/services (21%), and planning for the future/advance care planning (17%). Discussion: The FamilyStrong Program is among the first "real world" oncology clinic-based formal support services for advance cancer family caregivers.

Clinical correlates of the ability to consent to research participation in brain metastasis

OBJECTIVE

Impairment in the ability to provide informed consent is common in persons with brain metastasis. However, little is known about what factors contribute to this impairment in the patient group. Our objective is to determine if the associations between demographic, cognitive, and clinical variables correlate with the ability to provide informed consent in persons with brain metastasis.

METHODS

We administered a comprehensive neuropsychological battery to a group of 61 persons with brain metastasis. Demographic and clinical information was also collected. All diagnoses were made by board-certified oncologists and were verified histologically. Statistical analyses included Pearson's product-moment correlations, point biserial correlations, and linear regression.

RESULTS

Results indicated that combinations of education, verbal memory, executive function, whole brain radiation therapy, and chemotherapy affected various aspects of the ability to provide informed consent. Subsequent regression models demonstrated that these variables contributed a significant amount of shared variance to the ability to provide informed consent.

CONCLUSION

We found that the ability of persons with brain metastasis to provide informed consent is a cognitively complex ability that is also affected by education and treatment variables. This information can help clinical researchers in identifying persons with brain metastasis at risk of an impaired ability to provide informed consent and aid in the consenting process.

Capacity to consent to research participation in adults with metastatic cancer: comparisons of brain metastasis, non-CNS metastasis, and healthy controls

Background

To evaluate the ability of individuals with metastatic cancer to provide informed consent to research participation, we used a structured vignette-based interview to measure 4 consenting standards across 3 participant groups.

Methods

Participants included 61 individuals diagnosed with brain metastasis, 41 individuals diagnosed with non-CNS metastasis, and 17 cognitively intact healthy controls. All groups were evaluated using the Capacity to Consent to Research Instrument (CCRI), a performance-based measure of research consent capacity. The ability to provide informed consent to participate in research was evaluated across 4 consent standards: expressing choice, appreciation, reasoning, and understanding. Capacity performance ratings (intact, mild/moderate impairment, severe impairment) were identified based on control group performance.

Results

Results revealed that the brain metastasis group performed significantly lower than healthy controls on the consent standard of understanding, while both metastatic cancer groups performed below controls on the consent standard of reasoning. Both metastatic cancer groups performed similar to controls on the standards of appreciation and expressing choice. Approximately 60% of the brain metastasis group, 54% of the non-CNS metastasis group, and 18% of healthy controls showed impaired research consent capacity.

Conclusions

Our findings, using a performance-based assessment, are consistent with other research indicating that the research consent process may be overly cumbersome and confusing. This, in turn, may lead to research consent impairment not only in patient groups but also in some healthy adults with intact cognitive ability.

Cauda equina syndrome in an ovarian malignant-mixed müllerian tumor with leptomeningeal spread

Leptomeningeal metastasis is extremely rare in patients with ovarian cancer, but should be considered in patients presenting with neurologic deficits such as cauda equine syndrome. Given its poor prognosis and lack of data currently on management, additional studies are needed to optimize treatment regimens and improve outcomes.

ACTR-58. BASELINE REQUIREMENTS FOR NOVEL AGENTS BEING CONSIDERED FOR BRAIN CANCER EFFICACY TRIALS: REPORT OF AN ABTC WORKSHOP

Despite advances in the understanding of molecular pathways, the availability of NGS panels to identify potentially drugable mutations, the proliferation of targeted therapies, and the progress seen in other cancers, only one novel agent (temozolomide) has significantly improved the survival of patients with glioblastoma in the past three decades. A major factor distinguishing brain cancer from other malignancies is the presence of the blood-brain barrier that restricts entry into the central nervous system of over 95% of drugs currently approved by the FDA. Clinical investigators have historically justified glioblastoma efficacy trials with pharmacokinetic data documenting measurable brain concentrations in animals or in contrast enhancing brain tumor specimens from patients. However, the discovery of effective therapeutic agents (whose mechanism of action requires that the drug directly reaches the cancer) will likely require that therapeutic drug concentrations (rather than measurable levels or blood:brain ratios) be delivered to non-contrast enhancing regions of the brain. The importance of delivering therapeutic concentrations of drug to non-enhancing brain is highlighted by knowledge that a gross total resection of all enhancing portions of a glioblastoma provides no chance of cure and limited improvement in overall survival. Utilizing these more stringent emerging criteria to select novel agents for efficacy studies will encourage pre-clinical and phase I studies to define the CNS penetration of new drugs and determine a therapeutic concentration for each agent. This will aid in the rational prioritization of agents selected for phase II studies. A full report of the outcome of the ABTC workshop on this topic will be presented. This will include: 1) methods to determine “therapeutic” drug concentrations for glioblastoma, 2) methods to quantify drug concentrations in non-enhancing brain, 3) pharmacokinetic and pharmacodynamic considerations, and 4) potential shortcomings of this approach.

IMMU-18. IMMUNOGENOMIC RESPONDER PHENOTYPE FROM A PHASE I TRIAL OF ANTI-LAG3 OR ANTI-CD137 ALONE AND IN COMBINATION WITH ANTI-PD-1 IN PATIENTS WITH RECURRENT GBM

BACKGROUND

Immune checkpoint inhibitors (ICIs) are not uniformly effective in glioblastoma treatment. Immunogenomic determinants may identify patients who are most likely to benefit from these therapies. Therefore, we compared the immunogenomic phenotype of a responder to combination anti-LAG-3 and anti-PD-1 therapy to non-responders.

METHODS

We performed T cell receptor (TCR) sequencing and gene expression analysis on pre-treatment, post-chemoradiation, and post-immunotherapy tumor specimens of glioblastoma patients treated with anti-LAG3 in combination with anti-PD-1 after first recurrence (NCT02658981, ongoing). We evaluated T cell clonotypes and immunophenotype of serially collected peripheral blood mononuclear cells (PBMCs) during treatment using multi-parametric flow cytometry.

RESULTS

To date, six patients have been enrolled in the initial anti-LAG-3 and anti-PD-1 cohort. One patient demonstrated complete response, one had stable disease, and four had progressive disease by radiographic evaluation. The responder demonstrated substantially higher TCR clonality in the resected tumor at initial diagnosis compared to non-responders (mean 0.028 vs. 0.005). Shared tumor infiltrating clonotypes with pre-immunotherapy PBMCs exhibited an increase in frequency from initial resection (6.8%) to resection at recurrence (20%). The responder’s tumor at initial resection exhibited increased gene signatures of PD1low CD8+ T cells, chemokine signaling, and interferon gamma pathways. On PBMC phenotypic analysis, the responder demonstrated significantly higher percentages of CD137+ CD8+T cells (median 8.38% vs 3.24%, p=0.02) and lower percentages of Foxp3+CD137+ CD4+T cells compared to non-responders (median 18.5% vs. 38.5%, p=0.006). Interestingly, dynamic analysis of PBMCs showed that the responder demonstrated a lower percentage of PD1+ CD8+ T cells pre-immunotherapy (median 2.5% vs.12.4%, p=0.002), with persistent decrease over the course of treatment while non-responders showed no consistent pattern.

CONCLUSION

Our preliminary results demonstrate significant differences in tumor and peripheral blood immunogenomic characteristics between responder and non-responders to anti-LAG3 and anti-PD-1 therapy. These immunogenomic characteristics may help stratify patients’ response to combination ICIs.

Use of metformin and outcome of patients with newly diagnosed glioblastoma: Pooled analysis

Metformin has been linked to improve survival of patients with various cancers. There is little information on survival of glioblastoma patients after use of metformin. We assessed the association between metformin use and survival in a pooled analysis of patient data from 1,731 individuals from the randomized AVAglio, CENTRIC and CORE trials. We performed multivariate Cox analyses for overall survival (OS) and progression-free survival (PFS) comparing patients' use of metformin at baseline and/or during concomitant radiochemotherapy (TMZ/RT). Further exploratory analyses investigated the effect of metformin with a history of diabetes and nonfasting glucose levels in relation to OS or PFS of glioblastoma patients. Metformin alone or in any combination was not significantly associated with OS or PFS (at baseline, hazard ratio [HR] for OS = 0.87; 95% confidence interval [CI] = 0.65-1.16; HR for PFS = 0.84; 95% CI = 0.64-1.10; during TMZ/RT HR for OS = 0.97; 95% CI = 0.68-1.38; HR for PFS = 1.02; 95% CI = 0.74-1.41). We found a statistically nonsignificant association of metformin monotherapy with glioblastoma survival at baseline (HR for OS = 0.68; 95% CI = 0.42-1.10; HR for PFS = 0.57; 95% CI = 0.36-0.91), but not during the TMZ/RT period (HR for OS = 0.90; 95% CI = 0.51-1.56; HR for PFS = 1.05; 95% CI = 0.64-1.73). Diabetes mellitus or increased nonfasting glucose levels were not associated with a difference in OS or PFS in our selected study population. Metformin did not prolong survival of patients with newly diagnosed glioblastoma in our analysis. Additional studies may identify patients with specific tumor characteristics that are associated with potential benefit from treatment with metformin, possibly due to metabolic vulnerabilities.

Glioblastoma Mimicking Viral Encephalitis Responds to Acyclovir: A Case Series and Literature Review

Viral encephalitis and glioblastoma are both relatively rare conditions with poor prognoses. While the clinical and radiographic presentations of these diseases are often distinctly different, viral encephalitis can sometimes masquerade as glioblastoma. Rarely, glioblastoma can also be misdiagnosed as viral encephalitis. In some cases where a high-grade glioma was initially diagnosed as viral encephalitis, antiviral administration has proven effective for relieving early symptoms. We present three cases in which patients presented with symptoms and radiographic findings suggestive of viral encephalitis and experienced dramatic clinical improvement following treatment with acyclovir, only to later be diagnosed with glioblastoma in the region of suspected encephalitis and ultimately succumb to tumor progression.

Characterization of iPSCs derived from low grade gliomas revealed early regional chromosomal amplifications during gliomagenesis

INTRODUCTION

IDH1 mutation has been identified as an early genetic event driving low grade gliomas (LGGs) and it has been proven to exerts a powerful epigenetic effect. Cells containing IDH1 mutation are refractory to epigenetical reprogramming to iPSC induced by expression of Yamanaka transcription factors, a feature that we employed to study early genetic amplifications or deletions in gliomagenesis.

METHODS

We made iPSC clones from freshly surgically resected IDH1 mutant LGGs by forced expression of Yamanaka transcription factors. We sequenced the IDH locus and analyzed the genetic composition of multiple iPSC clones by array-based comparative genomic hybridization (aCGH).

RESULTS

We hypothesize that the primary cell pool isolated from LGG tumor contains a heterogeneous population consisting tumor cells at various stages of tumor progression including cells with early genetic lesions if any prior to acquisition of IDH1 mutation. Because cells containing IDH1 mutation are refractory to reprogramming, we predict that iPSC clones should originate only from LGG cells without IDH1 mutation, i.e. cells prior to acquisition of IDH1 mutation. As expected, we found that none of the iPSC clones contains IDH1 mutation. Further analysis by aCGH of the iPSC clones reveals that they contain regional chromosomal amplifications which are also present in the primary LGG cells.

CONCLUSIONS

These results indicate that there exists a subpopulation of cells harboring gene amplification but without IDH1 mutation in the LGG primary cell pool. Further analysis of TCGA LGG database demonstrates that these regional chromosomal amplifications are also present in some cases of low grade gliomas indicating they are reoccurring lesions in glioma albeit at a low frequency. Taken together, these data suggest that regional chromosomal alterations may exist prior to the acquisition of IDH mutations in at least some cases of LGGs.

Activation of the Receptor Tyrosine Kinase AXL Regulates the Immune Microenvironment in Glioblastoma

Glioblastoma (GBM) is a lethal disease with no effective therapies available. We previously observed upregulation of the TAM (Tyro-3, Axl, and Mer) receptor tyrosine kinase family member AXL in mesenchymal GBM and showed that knockdown of AXL induced apoptosis of mesenchymal, but not proneural, glioma sphere cultures (GSC). In this study, we report that BGB324, a novel small molecule inhibitor of AXL, prolongs the survival of immunocompromised mice bearing GSC-derived mesenchymal GBM-like tumors. We show that protein S (PROS1), a known ligand of other TAM receptors, was secreted by tumor-associated macrophages/microglia and subsequently physically associated with and activated AXL in mesenchymal GSC. PROS1-driven phosphorylation of AXL (pAXL) induced NFκB activation in mesenchymal GSC, which was inhibited by BGB324 treatment. We also found that treatment of GSC-derived mouse GBM tumors with nivolumab, a blocking antibody against the immune checkpoint protein PD-1, increased intratumoral macrophages/microglia and activation of AXL. Combinatorial therapy with nivolumab plus BGB324 effectively prolonged the survival of mice bearing GBM tumors. Clinically, expression of AXL or PROS1 was associated with poor prognosis for patients with GBM. Our results suggest that the PROS1-AXL pathway regulates intrinsic mesenchymal signaling and the extrinsic immune microenvironment, contributing to the growth of aggressive GBM tumors.Significance: These findings suggest that development of combination treatments of AXL and immune checkpoint inhibitors may provide benefit to patients with GBM. Cancer Res; 78(11); 3002-13. ©2018 AACR.

Addition of carbonic anhydrase 9 inhibitor SLC-0111 to temozolomide treatment delays glioblastoma growth in vivo

Tumor microenvironments can promote stem cell maintenance, tumor growth, and therapeutic resistance, findings linked by the tumor-initiating cell hypothesis. Standard of care for glioblastoma (GBM) includes temozolomide chemotherapy, which is not curative, due, in part, to residual therapy-resistant brain tumor-initiating cells (BTICs). Temozolomide efficacy may be increased by targeting carbonic anhydrase 9 (CA9), a hypoxia-responsive gene important for maintaining the altered pH gradient of tumor cells. Using patient-derived GBM xenograft cells, we explored whether CA9 and CA12 inhibitor SLC-0111 could decrease GBM growth in combination with temozolomide or influence percentages of BTICs after chemotherapy. In multiple GBMs, SLC-0111 used concurrently with temozolomide reduced cell growth and induced cell cycle arrest via DNA damage in vitro. In addition, this treatment shifted tumor metabolism to a suppressed bioenergetic state in vivo. SLC-0111 also inhibited the enrichment of BTICs after temozolomide treatment determined via CD133 expression and neurosphere formation capacity. GBM xenografts treated with SLC-0111 in combination with temozolomide regressed significantly, and this effect was greater than that of temozolomide or SLC-0111 alone. We determined that SLC-0111 improves the efficacy of temozolomide to extend survival of GBM-bearing mice and should be explored as a treatment strategy in combination with current standard of care.

Abstract 171: Targeting the tumor microenvironment: inhibition of carbonic anhydrase 9 impedes brain tumor initiating cell chemoresistance and delays glioblastoma growth in vivo

Brain tumor initiating cells (BTICs) are resistant to chemo- and radiotherapy, providing a reservoir for tumor recurrence and a desirable target for glioma treatments. Standard of care for glioblastoma (GBM; grade IV astrocytoma) includes the chemotherapeutic agent temozolomide, which prolongs life expectancy by months and is not curative. Prior studies suggested the efficacy of chemotherapies including temozolomide was increased by reducing expression of carbonic anhydrase 9 (CA9). CA9 is a hypoxia responsive gene elevated in tumors that is important for regulating intracellular pH and contributing to the acidic extracellular microenvironment. After confirming basal and hypoxia-induced expression of CA9 in GBM BTICs, we targeted CA9 activity with the small molecule inhibitor SLC-0111 alone or in combination with temozolomide. In multiple GBM BTIC lines, SLC-0111 reduced cell growth in vitro and showed additional benefit when used concurrently with temozolomide. Importantly, SLC-0111 inhibited the enrichment of BTICs after temozolomide treatment as determined via BTIC marker expression and neurosphere formation capacity. These data suggested the potential of SLC-0111 as a chemosensitizer, which we next evaluated in preclinical studies using a subcutaneous recurrent GBM model. GBMs treated with SLC-0111 in combination with temozolomide significantly regressed and the resulting in vivo growth delay was greater than that of temozolomide or SLC-0111 alone. Together, our data suggest that SLC-0111 can sensitize GBM BTICs to the chemotherapy temozolomide and significantly delay disease progression.

Citation Format: Nathaniel H. Boyd, Kiera Walker, Paul C. McDonald, Mark O. Bevensee, Yancey G. Gillespie, Burt Nabors, Shoukat Dedhar, Anita B. Hjelmeland. Targeting the tumor microenvironment: inhibition of carbonic anhydrase 9 impedes brain tumor initiating cell chemoresistance and delays glioblastoma growth in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 171. doi:10.1158/1538-7445.AM2017-171

Targeting integrins in malignant glioma

The integrin family of cell adhesion receptors is emerging as a promising target of anticancer therapy. AlphaVbeta3 and alphaVbeta5 integrins are overexpressed on both glioma cells and tumor vasculature. Cilengitide, the most advanced specific integrin inhibitor in oncology, has shown antitumor activity against glioma in early clinical trials. Durable remissions have been observed in phase I and phase II trials for recurrent glioblastoma (GBM) with both lower and higher doses of cilengitide. Pilot trials in newly diagnosed glioblastoma in conjunction with standard chemoradiotherapy have been encouraging. Preclinical data suggest synergy with concomitant chemo- and radiation therapy. A pivotal phase III study (CENTRIC) in newly diagnosed GBM patients is currently recruiting. This paper summarizes the current understanding of the role of integrins and their inhibition in gliomagenesis. The background and design of ongoing trials are outlined.

Phase IIa trial of cilengitide (EMD121974) single-agent therapy in patients (pts) with recurrent glioblastoma (GBM): EMD 121974-009

2002

Background: Our phase IIa study evaluated the safety, toxicity, and clinical activity of the cyclic RGD pentapeptide cilengitide (EMD121974), an inhibitor of integrins avβ3 and avβ5, as a single agent at doses of 500 and 2000 mg in pts with recurrent GBM. Methods: In this multicenter, open-label, randomized, uncontrolled study, pts with GBM and measurable disease that had relapsed after previous temozolomide and radiotherapy were randomized to receive cilengitide at either 500 mg or 2000 mg i.v., 2x/week, until progression. Neurologic exams were performed after every cycle (4 weeks) and MRIs were performed every other cycle. Central, blinded pathology and radiology reviews were performed. The primary endpoint was Progression Free Survival (PFS) at 6 months (6-mth PFS). Secondary endpoints included response, survival, time to disease progression, safety, tolerability and pharmacokinetics (PK). Results: 81 pts accrued (median Karnofsky Performance Status 80%; median age 57 yrs) at 15 sites including 41 at the 500 mg and 40 at the 2000 mg dose levels. Demographic and pretreatment variables were comparable between dose level cohorts. The median number of infusions was 16 [range, 4–179]. PK studies revealed significantly greater exposures among the 2000 mg cohort. Treatment related NCI CTC grade 3 adverse events (AEs) included elevated transaminases (at 500 mg), arthralgia/ myalgia (at 500 mg), and weight increase/ edema (at 2000 mg) in 1 patient, respectively. No grade 4 therapy related AEs were reported. One CTC grade 2 cerebral hemorrhage was reported in a pt at progression. The 6- mth PFS was 16.1% (n=13/81 pts). 10 pts (12.3 %, n=4 with 500 mg, n=6 with 2000 mg) received 12 or more cycles. Six pts (7.4%) remain progression-free and on treatment. Median Overall Survival (mOS) was 6.5 mths [95% CI: 5.2–9.3 mths] in the 500 mg arm and 9.9 mths [95% CI, 6.3–15.7 mths] in the 2000 mg arm. Although not statistically significant, there was a trend towards better tumor control in pts receiving 2000 mg 2x/week. Conclusions: Cilengitide was well tolerated and demonstrated single agent activity in recurrent GBM, with long term disease stabilization in a subset of pts.

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