P13.17 CD95 gene silencing affects growth and invasiveness of glioma-initiating cells in a CD95L-independent manner

BACKGROUND

CD95 (Fas/APO-1) holds a dual role of potential relevance in tumor development. CD95-CD95 ligand (CD95L) signaling regulates apoptotic cell death in CD95-expressing cells, but non-apoptotic, tumor-promoting CD95-CD95L signaling has been likewise described. Therapeutic stimulation of apoptotic CD95 signaling is associated with major clinical side effects. However, inhibition of tumor-promoting CD95 signaling may represent a promising treatment strategy for human cancers where potential tumor-promoting CD95 functions include invasiveness and cancer cell stemness, including glioblastoma.

MATERIAL AND METHODS

In this study, CD95 and CD95L expression was characterized in human glioma-initiating cells (GIC) in vitro and in vivo. CD95 and CD95L gene knockout (KO) GIC were generated by means of CRISPR-Cas9 and the effects of gene silencing were evaluated by assessing growth, clonogenicity, invasiveness and tumorigenicity in nude mice.

RESULTS

CD95 expression and sensitivity to exogenous CD95L-induced apoptosis were confirmed in selected GIC in vitro. CD95L expression was not detected. Upon CD95 KO, all GIC acquired resistance to CD95L-induced apoptosis. Furthermore, despite the confirmed absence of CD95L expression in vitro, CD95 KO S-24 GIC revealed decreased cell growth, inferior sphere forming capacity and decreased invasiveness. These data suggested a CD95L-independent tumor-promoting role of CD95 in S-24 GIC. In vivo, however, CD95 KO did not prolong the survival of glioma-bearing mice. Analyses of further GIC models are ongoing.

CONCLUSION

These data demonstrate that, unlike CD95, CD95L is not expressed in cultured human GIC and that CD95-CD95L interactions are not required for tumor-promoting CD95 signaling. Although CD95 KO is detrimental for S-24 GIC in vitro, CD95 KO alone does not affect survival in S-24 human GIC xenograft-bearing mice.

OS06.7A METPlatform identifies brain metastasis vulnerabilities and predicts patient response to therapy

BACKGROUND

The diagnosis of brain metastasis involves high morbidity and mortality and remains an unmet clinical need in spite of being the most common tumor in the brain. Exclusion of these cancer patients from clinical trials is a major cause of their limited therapeutic options.

MATERIAL AND METHODS

We report a novel drug-screening platform (METPlatform) based on organotypic cultures which allows identifying effective anti-metastasis agents in the presence of the organ microenvironment. We have applied this approach to clinically relevant stages of brain metastasis using both experimental models and human tumor tissue (by performing patient-derived organotypic cultures - PDOCs -). We have also used METPlatform to perform unbiased proteomics of brain metastases in situ to identify potential novel mediators of this disease and explore resistance mechanisms to targeted therapy. Finally, we have exploited METPlatform as “avatars” to predict response to therapy in patients with primary brain tumors.

RESULTS

We identified heat shock protein 90 (HSP90) as a promising therapeutic target for brain metastasis. DEBIO-0932, a blood-brain barrier permeable HSP90 inhibitor, shows high potency against mouse and human brain metastases from different primary origin and oncogenomic profile at clinically relevant stages of the disease, including a novel model of local relapse after neurosurgery. Furthermore, in situ proteomic analysis of brain metastases treated with the chaperone inhibitor revealed non-canonical clients of HSP90 as potential novel mediators of brain metastasis and actionable mechanisms of resistance driven by autophagy. Combined therapy using HSP90 and autophagy inhibitors showed synergistic effects compared to sublethal concentrations of each monotherapy, demonstrating the potential of METPlatform to design and test rationale combination therapies to target metastasis more effectively. Finally, we show that brain tumor PDOCs predict the response of the corresponding patient to standard of care, thus proving the potential of METPlatform for improving personalized care in cancer.

CONCLUSION

Our work validates METPlatform as a potent resource for metastasis research integrating drug-screening and unbiased omic approaches that is fully compatible with human samples and questions the rationale of excluding patients with brain metastasis from clinical trials. We envision that METPlatform will be established as a clinically relevant strategy to personalize the management of metastatic disease in the brain and elsewhere.

Fourfold Differential Photoelectron Circular Dichroism

We report on a joint experimental and theoretical study of photoelectron circular dichroism (PECD) in methyloxirane. By detecting O 1s photoelectrons in coincidence with fragment ions, we deduce the molecule's orientation and photoelectron emission direction in the laboratory frame. Thereby, we retrieve a fourfold differential PECD clearly beyond 50%. This strong chiral asymmetry is reproduced by ab initio electronic structure calculations. Providing such a pronounced contrast makes PECD of fixed-in-space chiral molecules an even more sensitive tool for chiral recognition in the gas phase.

Prognostic significance of genome-wide DNA methylation profiles within the randomised, phase 3, EORTC CATNON trial on non-1p/19q deleted anaplastic glioma

Background

Survival in patients with IDH1/2-mutant (mt) anaplastic astrocytomas is highly variable. We have used the prospective phase 3 CATNON trial to identify molecular factors related to outcome in IDH1/2mt anaplastic astrocytoma patients.

Methods

The CATNON trial randomized 751 adult patients with newly diagnosed 1p/19q non-codeleted anaplastic glioma to 59.4 Gy radiotherapy +/− concurrent and/or adjuvant temozolomide. The presence of necrosis and/or microvascular proliferation was scored at central pathology review. Infinium MethylationEPIC BeadChip arrays were used for genome-wide DNA methylation analysis and the determination of copy number variations (CNV). Two DNA methylation-based tumor classifiers were used for risk stratification. Next-generation sequencing (NGS) was performed using 1 of the 2 glioma-tailored NGS panels. The primary endpoint was overall survival measured from the date of randomization.

Results

Full analysis (genome-wide DNA methylation and NGS) was successfully performed on 654 tumors. Of these, 432 tumors were IDH1/2mt anaplastic astrocytomas. Both epigenetic classifiers identified poor prognosis patients that partially overlapped. A predictive prognostic Cox proportional hazard model identified that independent prognostic factors for IDH1/2mt anaplastic astrocytoma patients included; age, mini-mental state examination score, treatment with concurrent and/or adjuvant temozolomide, the epigenetic classifiers, PDGFRA amplification, CDKN2A/B homozygous deletion, PI3K mutations, and total CNV load. Independent recursive partitioning analysis highlights the importance of these factors for patient prognostication.

Conclusion

Both clinical and molecular factors identify IDH1/2mt anaplastic astrocytoma patients with worse outcome. These results will further refine the current WHO criteria for glioma classification.

Strong Differential Photoion Circular Dichroism in Strong-Field Ionization of Chiral Molecules

We investigate the differential ionization probability of chiral molecules in the strong-field regime as a function of the helicity of the incident light. To this end, we analyze the fourfold ionization of bromochlorofluoromethane (CHBrClF) with subsequent fragmentation into four charged fragments and different dissociation channels of the singly ionized methyloxirane. By resolving for the molecular orientation, we show that the photoion circular dichroism signal strength is increased by 2 orders of magnitude.

From first symptoms to diagnosis: Initial clinical presentation of primary brain tumors

Background:

Despite modern imaging methods, a long symptom-to-diagnosis interval can be observed in patients with primary brain tumors.

Objective:

The study evaluated the initial and subsequent clinical presentation of patients with brain tumors in the context of time to diagnosis, localization, histology, and tumor grading.

Methods:

In this retrospective analysis of 85 consecutive patients with primary brain tumors, we assessed the presenting symptoms and signs. The analyses were based on entries from medical records at the Department of Neurology of Zurich University Hospital between 2005 and 2010.

Results:

A total of 54 men and 31 women with a mean age at diagnosis of 48 years were included. 60% of the patients present with a malignant tumor (World Health Organization grading III–IV), 24.7% with a benign tumor (I–II), and 15.3% were not classified. The interval between symptom onset and diagnosis varied from 1 day to 96 months (median: 39 days). High-grade tumors (III–IV) were diagnosed significantly earlier than low-grade tumors (II) after the first symptoms occurred (median: 26 vs. 138 days; z = −3.847, p < 0.001).

Conclusions:

Symptoms with a short symptom-to-diagnosis interval such as nausea/vomiting, seizures, as well as of personality change are assumed to contribute to a faster diagnosis in high-grade tumors. Visual disturbances and headaches, although occurring relatively seldom, did not contribute to a decrease in time to diagnosis and should therefore be considered for further diagnostic workup.

Addressing a national crisis: the spine hospital and department's response to the COVID-19 pandemic in New York City

In a very brief period, the COVID-19 pandemic has swept across the planet leaving governments, societies, and healthcare systems unprepared and under-resourced. New York City now represents the global viral epicenter with roughly one-third of all mortalities in the United States. To date, our hospital has treated thousands of COVID-19 positive patients and sits at the forefront of the United States response to this pandemic. The goal of this paper is to share the lessons learned by our spine division during a crisis when hospital resources and personnel are stretched thin. Such experiences include management of elective and emergent cases, outpatient clinics, physician redeployment, and general health and wellness. As peak infections spread across the United States, we hope this article will serve as a resource for other spine departments on how to manage patient care and healthcare worker deployment during the COVID-19 crisis.

Fampridine-induced changes in walking kinetics are associated with clinical improvements in patients with multiple sclerosis

Gait dysfunction is common in patients with multiple sclerosis (PwMS). Treatment with prolonged-release fampridine (PR-fampridine) improves walking ability in some PwMS. Associated fampridine-induced changes in the walking pattern are still poorly understood but may provide a better understanding of the mechanisms underlying the beneficial drug effects. 61 PwMS were treated with PR-fampridine in a randomized, monocentric, double-blind and placebo-controlled clinical trial with crossover design (FAMPKIN). Drug-induced improvements in walking speed (Timed-25-Foot Walk; T25FW) and endurance (6-Minute Walk Test; 6MWT) were quantified. In this sub-study of the FAMPKIN trial, fampridine-induced changes in kinetic gait patterns were analyzed by pressure-based foot print analysis during treadmill walking. Vertical ground reaction forces were analyzed during different gait phases. Kinetic data of 44 PwMS was eligible for analysis. During double-blind treatment with PR-fampridine, patients performed significantly better in the T25FW and 6MWT than during placebo treatment (p < 0.0001 for both). At the group level (n = 44), there were no significant changes of gait kinetics under PR-fampridine vs. placebo. However, we found relevant changes of walking kinetics regarding forces during loading, single limb and pre-swing phase in a patient sub-group (n = 8). Interestingly, this sub-group demonstrated superior responsiveness to PR-fampridine in the clinical walking tests compared to those patients without any fampridine-induced changes in kinetics (n = 36). Our results demonstrate fampridine-induced changes in gait kinetics in a sub-group of PwMS. These gait pattern changes were accompanied by improved clinical walking performance under PR-fampridine. These results shed some light on the biomechanical changes in walking patterns underlying enhanced fampridine-induced gait performance.

Embolization of tumor cells is rare in patients with systemic cancer and cerebral large vessel occlusion

BACKGROUND AND PURPOSE

Stroke is a dreaded complication in patients with cancer. Besides paraneoplastic coagulopathy, chemotherapy, radiotherapy and tumor-directed invasive procedures, circulating cancer cells may contribute to thrombus formation and embolic stroke. However, the incidence of tumor cells within the blood clots of cancer patients with stroke is unknown and the role of circulating tumor cells in the formation of cerebrovascular thrombi remains unclear.

METHODS

All patients who had undergone cerebrovascular thrombectomy at the University Hospital Zurich between 2014 and 2017 were screened for history of cancer. Clinical information was retrieved from the local stroke registry and the electronic charts and thrombi underwent a thorough histopathological re-review.

RESULTS

Thirty-two of 182 patients (18%) with thrombectomy had a history of cancer. The majority of patients had advanced stage cancer. However, even after extensive histopathological re-review, only one specimen revealed tumor cells in the thrombus: a 75-year-old patient with acute occlusion of the middle cerebral artery who had been diagnosed with non-small-cell lung cancer 8.1 months prior to stroke.

CONCLUSIONS

The presence of cancer cells in clots from cerebrovascular thrombectomy, indicative of a direct involvement of circulating tumor cells in the causation of stroke, is rare.

My Baby's Movements: a stepped wedge cluster randomised controlled trial to raise maternal awareness of fetal movements during pregnancy study protocol

Background

Stillbirth is a devastating pregnancy outcome that has a profound and lasting impact on women and families. Globally, there are over 2.6 million stillbirths annually and progress in reducing these deaths has been slow. Maternal perception of decreased fetal movements (DFM) is strongly associated with stillbirth. However, maternal awareness of DFM and clinical management of women reporting DFM is often suboptimal. The My Baby’s Movements trial aims to evaluate an intervention package for maternity services including a mobile phone application for women and clinician education (MBM intervention) in reducing late gestation stillbirth rates.

Methods/design

This is a stepped wedge cluster randomised controlled trial with sequential introduction of the MBM intervention to 8 groups of 3–5 hospitals at four-monthly intervals over 3 years.

The target population is women with a singleton pregnancy, without lethal fetal abnormality, attending for antenatal care and clinicians providing maternity care at 26 maternity services in Australia and New Zealand. The primary outcome is stillbirth from 28 weeks’ gestation. Secondary outcomes address: a) neonatal morbidity and mortality; b) maternal psychosocial outcomes and health-seeking behaviour; c) health services utilisation; d) women’s and clinicians’ knowledge of fetal movements; and e) cost. 256,700 births (average of 3170 per hospital) will detect a 30% reduction in stillbirth rates from 3/1000 births to 2/1000 births, assuming a significance level of 5%. Analysis will utilise generalised linear mixed models.

Discussion

Maternal perception of DFM is a marker of an at-risk pregnancy and commonly precedes a stillbirth. MBM offers a simple, inexpensive resource to reduce the number of stillborn babies, and families suffering the distressing consequences of such a loss. This large pragmatic trial will provide evidence on benefits and potential harms of raising awareness of DFM using a mobile phone app.

Trial registration

ACTRN12614000291684. Registered 19 March 2014.

Version

Protocol Version 6.1, February 2018.

Bevacizumab plus hypofractionated radiotherapy versus radiotherapy alone in elderly patients with glioblastoma: the randomized, open-label, phase II ARTE trial

Background

The addition of bevacizumab to temozolomide-based chemoradiotherapy (TMZ/RT → TMZ) did not prolong overall survival (OS) in patients with newly diagnosed glioblastoma in phase III trials. Elderly and frail patients are underrepresented in clinical trials, but early reports suggested preferential benefit in this population.

Patients and methods

ARTE was a 2 : 1 randomized, multi-center, open-label, non-comparative phase II trial of hypofractionated RT (40 Gy in 15 fractions) with bevacizumab (10 mg/kg×14 days) (arm A, N = 50) or without bevacizumab (arm B, N = 25) in patients with newly diagnosed glioblastoma aged ≥65 years. The primary objective was to obtain evidence for prolongation of median OS by the addition of bevacizumab to RT. Response was assessed by RANO criteria. Quality of life (QoL) was monitored by the EORTC QLQ-C30/BN20 modules. Exploratory studies included molecular subtyping by 450k whole methylome and gene expression analyses.

Results

Median PFS was longer in arm A than in arm B (7.6 and 4.8 months, P = 0.003), but OS was similar (12.1 and 12.2 months, P = 0.77). Clinical deterioration was delayed and more patients came off steroids in arm A. Prolonged PFS in arm A was confined to tumors with the receptor tyrosine kinase (RTK) I methylation subtype (HR 0.25, P = 0.014) and proneural gene expression (HR 0.29, P = 0.025). In a Cox model of OS controlling for established prognostic factors, associations with more favorable outcome were identified for age <70 years (HR 0.52, P = 0.018) and Karnofsky performance score 90%-100% (HR 0.51, P = 0.026). Including molecular subtypes into that model identified an association of the RTK II gene methylation subtype with inferior OS (HR 1.73, P = 0.076).

Conclusion

Efficacy outcomes and exploratory analyses of ARTE do not support the hypothesis that the addition of bevacizumab to RT generally prolongs survival in elderly glioblastoma patients. Molecular biomarkers may identify patients with preferential benefit from bevacizumab.

Clinical trial registration number

NCT01443676.

P11.45 Synergistic growth inhibition mediated by dual PI3K/mTOR pathway targeting and genetic or direct pharmacological AKT inhibition in human glioblastoma models

BACKGROUND

Molecular genetic aberrations in the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway are common in human cancers including glioblastoma, yet, novel therapeutic approaches targeting this pathway in glioblastoma have had limited success to date.

MATERIAL AND METHODS

Here we analyzed the molecular mechanisms determining sensitivity to PI3K/mTOR inhibition using gene silencing or pharmacological target inhibition, and effects on proliferation, and clonogenicity or spherogenicity as readouts, in an extended panel of human long-term glioma cell (LTC) lines and glioma-initiating cells (GIC).

RESULTS

Glioma cells, including GIC in particular, were universally sensitive to growth inhibition induced by PQR309, a novel, dual pan-PI3K/mTOR antagonist in vitro. Cells exhibited profound growth arrest, but little apoptotic or necrotic cell death as confirmed by electron microscopy; yet, there was evidence of senescence. In vivo studies confirmed the anti-glioma activity of PQR309 in the orthotopic LN-229 glioma model. Cell lines with high basal levels of phosphorylated (active) AKT, low levels of phosphorylated (inactive) protein translation repressor eukaryotic initiation factor (eIF) 4E-binding protein 1 (p4E-BP1), and high levels of Ser9-phosphorylated (inactive) glycogen synthase kinase 3 beta (pGSK3ß) were more sensitive to PQR309. Accordingly, the activity of PQR309 was synergistically enhanced by AKT gene silencing or direct pharmacological AKT inhibition.

CONCLUSION

These data justify to explore combined targeted therapy approaches in glioblastoma that aim at down-regulating AKT function to enhance the therapeutic potential of dual PI3K/mTOR inhibitors.

PL3.3 Second interim and first molecular analysis of the EORTC randomized phase III intergroup CATNON trial on concurrent and adjuvant temozolomide in anaplastic glioma without 1p/19q codeletion

BACKGROUND

The 1st interim analysis of the CATNON trial showed benefit from adjuvant (adj) temozolomide (TMZ) on overall survival (OS) but remained inconclusive about concurrent (conc) TMZ. A 2nd interim analysis was planned after 356 events.

MATERIAL AND METHODS

The 2x2 factorial design phase III CATNON trial randomized 751 adult patients with newly diagnosed non-codeleted anaplastic glioma to either 59.4 Gy radiotherapy (RT) alone; the same RT with concTMZ; the same RT and 12 cycles of adjTMZ or the same RT with both concTMZ and adjTMZ (doi: 10.1016/S0140-6736(17)31442-3). MGMT promoter methylation (MGMTmeth) status was re-assessed with the Infinium Methylation EPIC Beadchip using the MGMT_STP27 model. Isocitrate dehydrogenase 1 and 2 (IDH) mutation (mt) status was assessed with glioma targeted Agilent SureSelect baits sequence using an Illumina HiSeq2500 Rapid PE100.

RESULTS

With a median follow-up of 56 months and 356 events, the hazard ratio (HR) for OS adjusted for stratification factors after concTMZ was 0.968 (99.1% CI 0.73, 1.28). 5-year OS was 50.2% with and 52.7% without concTMZ (95% CI [44.4, 55.7] and [46.9, 58.1]). An IDHmt was found in 335 of 480 assessed cases (70%). Median OS was 19 mo (95% CI 16.3, 22.3) in IDHwt tumors and 116 mo (95% CI 82.0, 116.6) in IDHmt tumors. The interaction test based on IDH status was significant (p=0.016) in the univariate HR analysis for OS after concTMZ (IDHwt, n=145, events=120, HR = 1.27, 95% CI 0.89, 1.82, p=0.19; IDHmt, n=335, events=92, HR= 0.67, 95% CI 0.44, 1.03, p=0.06). IDHmt was predictive of benefit from adjTMZ (IDHmt HR: 0.41, 95% CI 0.27, 0.64; IDHwt: HR 1.05, 95% CI 0.73, 1.52; interaction test p = 0.001). In IDHmt patients that received adjTMZ, the HR for OS after concTMZ was 0.71 (95% CI 0.35, 1.42, p=0.32). MGMTmeth was found in 288 of 410 assessed cases (70%), interaction test for concTMZ (p = 0.092) and adjTMZ (p = 0.166) did not reach statistical significance.

CONCLUSION

In the entire study cohort, concTMZ did not increase OS. However, in IDHmt tumors a trend towards benefit of concTMZ is present. AdjTMZ increased OS in IDHmt but not in IDHwt tumors. Further analyses and follow-up will allow full assessment of efficacy in the molecular subgroups.

PL3.2 Trabectedin for recurrent WHO grade II or III meningioma: a randomized phase II study of the EORTC Brain Tumor Group (EORTC-1320-BTG)

BACKGROUND

EORTC-1320-BTG investigated the activity, safety and quality of life of therapy with the tetrahydroisoquinoline alkaloid trabectedin (Yondelis®) in patients with recurrent higher-grade meningiomas. Trabectedin was originally derived from the Caribbean sea squirt, Ecteinascidia turbinata, and currently is manufactured by total synthesis.

METHODS

Adult patients with histological diagnosis of WHO grade II or III meningioma and radiologically documented progression after maximal feasible surgery and radiotherapy were randomly assigned in a 2:1 ratio to receive intravenous trabectedin (1.5 mg/m2every three weeks) or local standard of care (LOC). The primary endpoint was progression-free survival (PFS).

RESULTS

Within 22.1 months, we randomized a total of 90 patients (n=29 in LOC arm, n=61 in trabectedin arm) in 35 institutions and nine countries. In the LOC arm, the following treatments were administered: hydroxyurea (n=11), bevacizumab (n=9), none (n=4), chemotherapy (n=3), somatostatin analogue (n=1), combined chemotherapy and somatostatin analogue (n=1). With 71 PFS events, median PFS was 4.17 months in the LOC and 2.43 months in the trabectedin arm (hazard ratio [HR] for progression, 1.42; 80% CI, 1.00–2.03; p=0.204) with a PFS-6 rate of 29.1% (95% CI, 11.9%-48.8%) in the LOC and 21.1% (95% CI, 11.3%-32.9%) in the trabectedin arm. Median OS was 10.61 months in the LOC and 11.37 months in the trabectedin arm (HR for death, 0.98; 95% CI, 0.54–1.76; p=0.94).Grade 3 to 5 adverse events occurred in 44.4% (18.5% related, 4 serious adverse events, 0 lethal events) of the patients in the LOC and 59% (32.8% related, 57 serious adverse events and 2 toxic deaths) of patient in the trabectedin arm.

CONCLUSIONS

In this first prospective randomized trial performed in recurrent grade II or III meningioma, trabectedin did not improve PFS and OS and was associated with significantly higher toxicity as compared to LOC treatment. The data collected in this study may serve as benchmark for future clinical trials in this setting.

P14.108 Bevacizumab versus alkylating chemotherapy in recurrent glioblastoma

BACKGROUND

The use of alkylating chemotherapy versus bevacizumab for recurrent glioblastoma remains controversial. Here we tested the hypothesis that the activity of alkylators, but not that of bevacizumab, would be associated with the O6-methylguanine DNA methyltransferase (MGMT) promoter methylation status

PATIENTS AND METHODS

We analyzed a cohort of patients treated at centers of the German Glioma Network or the University Hospital Zurich with alkylating agent-based chemotherapy (n=260) or bevacizumab without or with irinotecan (n=84) for first recurrence of glioblastoma. Outcome was stratified for MGMT status and cross-over to bevacizumab or alkylators at further tumor progression.

RESULTS

Median post-recurrence survival-1 (PRS-1) for patients receiving alkylating agent chemotherapy at first recurrence was longer than for patients receiving bevacizumab (11.1 versus 7.4 months, p<0.001). The use of alkylating agents was associated with longer PRS-1 for patients with a methylated versus an unmethylated MGMT promoter (p=0.017). For patients receiving bevacizumab, PRS-1 was not different with or without MGMT promoter methylation. PRS-1 was longer in the group receiving alkylating chemotherapy compared to bevacizumab for patients with a methylated (p<0.001) or unmethylated MGMT promoter (p=0.034). For patients with alkylators at first recurrence receiving bevacizumab at any further recurrence, PRS-1 was longer than in patients receiving bevacizumab first and alkylators thereafter (p=0.002).

CONCLUSION

This study confirms limited value of bevacizumab in recurrent glioblastoma independent of MGMT status. Alkylating agents have activity in recurrent glioblastoma, especially in the context of a methylated MGMT promoter.

OS7.2 Measuring change in health-related quality of life: the added value of analysis on the individual patient level in glioma patients in clinical decision making

BACKGROUND

Health-related quality of life (HRQoL) is often used as an outcome in glioma research, reflecting the impact of disease and treatment on a patient’s functioning and wellbeing. Data on changes in HRQoL scores may provide important information for clinical decision-making, but different analytical methods may lead to different interpretations of the impact of treatment on HRQoL. This study aimed to examine three different methods to evaluate change in HRQoL, and to study whether these methods result in different interpretations.

MATERIAL AND METHODS

HRQoL and sociodemographical/clinical data from 15 randomized clinical trials were combined. Change in HRQoL scores was analyzed in three ways: (1) at the group level, comparing mean changes in scale/item scores between treatment arms over time, (2) at the patient level per scale/item by calculating the percentage of patients that deteriorated, improved or remained stable on a scale/item per scale/item, and (3) at the individual patient level combining all scales/items.

RESULTS

Baseline and first follow-up HRQoL data were available for 3727 patients. At the group scale/item level (method 1), only the item ‘hair loss’ showed a significant and clinically relevant change (i.e. ≥10 points) over time, whereas change scores on the other scales/items showed a statistically significant change only (all p<.001, range in change score: 0.1–6.2). Analyses on the patient level per scale (method 2) indicated that, while a large proportion of patients had stable HRQoL over time (range 27–84%), many patients deteriorated (range: 6–43%) or improved (range: 8–32%) on a specific scale/item. At the individual patient level (method 3), the majority of patients (86%) showed both deterioration and improvement, while only 1% of the patients remained stable on all scales. Clustering on clinical characteristics (WHO performance status, sex, tumor type, type of resection, newly diagnosed versus recurrent tumor and age) did not identify subgroups of patients with a specific pattern of change in their HRQoL score.

CONCLUSION

Different analytical methods of changes in HRQoL result in distinct interpretations of treatment effects, all of which may be relevant for clinical decision-making. Additional information about the joint impact of treatment on all outcomes, showing that most patients experience both deterioration and improvement, may help patients and physicians to make the best treatment decision.

P12.08 Immunocytokines are a novel immunotherapeutic approach against glioblastoma

BACKGROUND

Glioblastoma is the most common malignant primary brain tumor in adults with an urgent need for novel treatment options. The administration of pro-inflammatory cytokines could be a potent immunotherapeutic approach to shift the balance between tumor-associated immunosuppression and immune activation. However, the systemic administration of therapeutically active doses of pro-inflammatory cytokines is not feasible due to toxic side effects and there is a need for strategies that enable a targeted delivery of pro-inflammatory cytokines to the tumor site.

METHODS

We investigated different antibody-cytokine fusion products that enable a targeted delivery of interleukin (IL)-2, IL-12 or tumor necrosis factor (TNF)-α to the tumor site by binding to a tumor-specific epitope of fibronectin. We investigated the expression of this tumor-specific epitope ex vivo in tumor-bearing mouse brains and human glioblastoma samples. Subsequently, we assessed the anti-tumor activity of IL-2, IL-12 or TNF-α fused to an antibody targeting this tumor-specific epitope in orthotopic syngeneic mouse glioma models.

RESULTS

The tumor-specfic extra domain B of fibronectin is expressed in murine glioma models and human glioblastoma samples. A fluorochrome-labeled antibody targeting this tumor-specific epitope accumulated at the tumor site in the brain in vivo upon systemic administration. IL-2, IL-12, or TNF-α fused to this antibody conferred a survival benefit in orthotopic tumor-bearing mice and cured a fraction of tumor-bearing mice. Mechanistically, antibody-fused TNF-α induced tumor necrosis and increased the activation of tumor-infiltrating natural killer (NK) cells, whereas antibody-fused IL-12 mainly boosted an anti-tumor immune response mediated by NK cells and T cells.

CONCLUSION

We demonstrate the expression of a tumor-specific epitope of fibronectin in glioblastoma and exploit this for the targeted delivery of IL-2, IL-12 or TNF-α to the tumor site. Our preclinical assessments indicate potent anti-tumor activity in orthotopic, syngneic glioma mouse models and reveal the mode of action for the different immunocytokines. Based on these findings, we initiated a phase I/II clinical trial in patients with recurrent glioma to investigate the targeted delivery of TNF-α (ClinicalTrials.gov identifier NCT03779230).

P14.124 EORTC 1709/CCTG CE.8: A phase III trial of marizomib in combination with standard temozolomide-based radiochemotherapy versus standard temozolomide-based radiochemotherapy alone in patients with newly diagnosed glioblastoma

BACKGROUND

The standard of care for patients with newly diagnosed glioblastoma includes maximal debulking surgery followed by radiotherapy (RT), and concomitant as well as maintenance therapy with the alkylating agent, temozolomide (TMZ). However, the prognosis remains poor and novel treatment strategies are urgently needed. Targeting the proteasome has been considered a promising anti-cancer approach for several years. Marizomib is a novel, irreversible and pan-proteasome inhibitor, which crosses the blood-brain barrier and has been assessed in phase I trials in patients with newly diagnosed or recurrent glioblastoma.

MATERIAL AND METHODS

EORTC 1709/CCTG CE.8 is a randomized, controlled, open label phase III superiority trial. Patients with histologically confirmed newly diagnosed glioblastoma and a performance status >70 are eligible. Patients are randomized in a 1:1 ratio to receive standard of care (TMZ/RT→TMZ) alone or TMZ/RT→TMZ plus marizomib. The study aims at enrolling 750 patients. Stratification factors include study site, age, performance status and extent of resection. The primary objective of this trial is to compare overall survival in patients receiving marizomib in addition to standard of care with those receiving standard treatment only. The testing strategy specifies the determination of this objective in the intent-to-treat population as well as the subgroup of patients with MGMT-unmethylated tumors. Secondary endpoints include progression-free survival, safety, neurocognitive function and quality of life. A translational research program has been set up. The study will be activated at approximately 50 EORTC sites across Europe, 25 sites in Canada and additional sites in the US. Patient recruitment started in June 2018 and as of April 29, 2019, a total of 164 patients have been randomized. An update on the enrolment status will be provided at the EANO meeting. ClinicalTrials.gov Identifier: NCT03345095

P11.08 Defining EGFR amplification status for clinical trial inclusion

BACKGROUND

Precision medicine trials targeting the epidermal growth factor receptor (EGFR) in glioblastoma patients require selection for EGFR-amplified tumors. However, there is currently no golden standard in determining the amplification status of EGFR or EGFRvIII expression. Here, we aimed to determine which technique and which cut-offs are suitable to determine EGFR amplification status.

MATERIAL AND METHODS

We compared fluorescent in-situ hybridization (FISH) and RT-qPCR data from patients screened for trial inclusion into the Intellance 2 clinical trial, with data from a panel-based next generation sequencing (NGS) platform (both DNA and RNA).

RESULTS

By using data from >1000 samples, we show which cut-offs are optimal to determine EGFR gene amplification by FISH. Our data also show that gene amplification (as determined by FISH) correlates with EGFR expression levels (as determined by RT-qPCR) with ROC analysis showing an under the curve area of up to 0.902. EGFR expression as assessed by RT-qPCR therefore may function as a surrogate marker for EGFR amplification. Our NGS data shows that EGFR copy numbers can strongly vary between tumors with levels ranging from 2 to more than 100 copies per cell. Levels exceeding 5 gene copies can be used to define EGFR-amplification by NGS; below this level FISH detects very few (if any) EGFR amplified nuclei and none of the samples express EGFRvIII.

CONCLUSION

Our data from central laboratories and diagnostic sequencing facilities, using material from patients eligible for clinical trial inclusion, help defining the optimal cut-off for various techniques to determine EGFR amplification for diagnostic purposes.