Improved prognostic stratification of patients with isocitrate dehydrogenase-mutant astrocytoma.

Prognostic factors and standards of care for astrocytoma, isocitrate dehydrogenase (IDH)-mutant, CNS WHO grade 4, remain poorly defined. Here we sought to explore disease characteristics, prognostic markers, and outcome in patients with this newly defined tumor type. We determined molecular biomarkers and assembled clinical and outcome data in patients with IDH-mutant astrocytomas confirmed by central pathology review. Patients were identified in the German Glioma Network cohort study; additional cohorts of patients with CNS WHO grade 4 tumors were identified retrospectively at two sites. In total, 258 patients with IDH-mutant astrocytomas (114 CNS WHO grade 2, 73 CNS WHO grade 3, 71 CNS WHO grade 4) were studied. The median age at diagnosis was similar for all grades. Karnofsky performance status at diagnosis inversely correlated with CNS WHO grade (p < 0.001). Despite more intensive treatment upfront with higher grade, CNS WHO grade was strongly prognostic: median overall survival was not reached for grade 2 (median follow-up 10.4 years), 8.1 years (95% CI 5.4-10.8) for grade 3, and 4.7 years (95% CI 3.4-6.0) for grade 4. Among patients with CNS WHO grade 4 astrocytoma, median overall survival was 5.5 years (95% CI 4.3-6.7) without (n = 58) versus 1.8 years (95% CI 0-4.1) with (n = 12) homozygous CDKN2A deletion. Lower levels of global DNA methylation as detected by LINE-1 methylation analysis were strongly associated with CNS WHO grade 4 (p < 0.001) and poor outcome. MGMT promoter methylation status was not prognostic for overall survival. Histomolecular stratification based on CNS WHO grade, LINE-1 methylation level, and CDKN2A status revealed four subgroups of patients with significantly different outcomes. In conclusion, CNS WHO grade, global DNA methylation status, and CDKN2A homozygous deletion are prognostic in patients with IDH-mutant astrocytoma. Combination of these parameters allows for improved prediction of outcome. These data aid in designing upcoming trials using IDH inhibitors.

INTERCEPT H3: a multicenter phase I peptide vaccine trial for the treatment of H3-mutated diffuse midline gliomas.

INTRODUCTION: Diffuse midline gliomas (DMG) are universally lethal central nervous system tumors that carry almost unanimously the clonal driver mutation histone-3 K27M (H3K27M). The single amino acid substitution of lysine to methionine harbors a neoantigen that is presented in tumor tissue. The long peptide vaccine H3K27M-vac targeting this major histocompatibility complex class II (MHC class II)-restricted neoantigen induces mutation-specific immune responses that suppress the growth of H3K27M+ flank tumors in an MHC-humanized rodent model. METHODS: INTERCEPT H3 is a non-controlled open label, single arm, multicenter national phase 1 trial to assess safety, tolerability and immunogenicity of H3K27M-vac in combination with standard radiotherapy and the immune checkpoint inhibitor atezolizumab (ATE). 15 adult patients with newly diagnosed K27M-mutant histone-3.1 (H3.1K27M) or histone-3.3 (H3.3K27M) DMG will be enrolled in this trial. The 27mer peptide vaccine H3K27M-vac will be administered concomitantly to standard radiotherapy (RT) followed by combinatorial treatment with the programmed death-ligand 1 (PD-L1) targeting antibody ATE. The first three vaccines will be administered bi-weekly (q2w) followed by a dose at the beginning of recovery after RT and six-weekly administrations of doses 5 to 11 thereafter. In a safety lead-in, the first three patients (pts. 1-3) will be enrolled sequentially. PERSPECTIVE: H3K27M-vac is a neoepitope targeting long peptide vaccine derived from the clonal driver mutation H3K27M in DMG. The INTERCEPT H3 trial aims at demonstrating (1) safety and (2) immunogenicity of repeated fixed dose vaccinations of H3K27M-vac administered with RT and ATE in adult patients with newly diagnosed H3K27M-mutant DMG. TRIAL REGISTRATION: NCT04808245.

Undetected pseudoprogressions in the CeTeG/NOA-09 trial: hints from postprogression survival and MRI analyses.

PURPOSE: In the randomized CeTeG/NOA-09 trial, lomustine/temozolomide (CCNU/TMZ) was superior to TMZ therapy regarding overall survival (OS) in MGMT promotor-methylated glioblastoma. Progression-free survival (PFS) and pseudoprogression rates (about 10%) were similar in both arms. Further evaluating this discrepancy, we analyzed patterns of postprogression survival (PPS) and MRI features at first progression according to modified RANO criteria (mRANO). METHODS: We classified the patients of the CeTeG/NOA-09 trial according to long vs. short PPS employing a cut-off of 18 months and compared baseline characteristics and survival times. In patients with available MRIs and confirmed progression, the increase in T1-enhancing, FLAIR hyperintense lesion volume and the change in ADC mean value of contrast-enhancing tumor upon progression were determined. RESULTS: Patients with long PPS in the CCNU/TMZ arm had a particularly short PFS (5.6 months). PFS in this subgroup was shorter than in the long PPS subgroup of the TMZ arm (11.1 months, p = 0.01). At mRANO-defined progression, patients of the CCNU/TMZ long PPS subgroup had a significantly higher increase of mean ADC values (p = 0.015) and a tendency to a stronger volumetric increase in T1-enhancement (p = 0.22) as compared to long PPS patients of the TMZ arm. CONCLUSION: The combination of survival and MRI analyses identified a subgroup of CCNU/TMZ-treated patients with features that sets them apart from other patients in the trial: short first PFS despite long PPS and significant increase in mean ADC values upon mRANO-defined progression. The observed pattern is compatible with the features commonly observed in pseudoprogression suggesting mRANO-undetected pseudoprogressions in the CCNU/TMZ arm of CeTeG/NOA-09.

Long-term neurocognitive function and quality of life after multimodal therapy in adult glioma patients: a prospective long-term follow-up.

PURPOSE: Multimodal therapies have significantly improved prognosis in glioma. However, in particular radiotherapy may induce long-term neurotoxicity compromising patients' neurocognition and quality of life. The present prospective multicenter study aimed to evaluate associations of multimodal treatment with neurocognition with a particular focus on hippocampal irradiation. METHODS: Seventy-one glioma patients (WHO grade 1-4) were serially evaluated with neurocognitive testing and quality of life questionnaires. Prior to (baseline) and following further treatment (median 7.1 years [range 4.6-11.0] after baseline) a standardized computerized neurocognitive test battery (NeuroCog FX) was applied to gauge psychomotor speed and inhibition, verbal short-term memory, working memory, verbal and non-verbal memory as well as verbal fluency. Mean ipsilateral hippocampal radiation dose was determined in a subgroup of 27 patients who received radiotherapy according to radiotherapy plans to evaluate its association with neurocognition. RESULTS: Between baseline and follow-up mean performance in none of the cognitive domains significantly declined in any treatment modality (radiotherapy, chemotherapy, combined radio-chemotherapy, watchful-waiting), except for selective attention in patients receiving chemotherapy alone. Apart from one subtest (inhibition), mean ipsilateral hippocampal radiation dose > 50 Gy (Dmean) as compared to < 10 Gy showed no associations with long-term cognitive functioning. However, patients with Dmean < 10 Gy showed stable or improved performance in all cognitive domains, while patients with > 50 Gy numerically deteriorated in 4/8 domains. CONCLUSIONS: Multimodal glioma therapy seems to affect neurocognition less than generally assumed. Even patients with unilateral hippocampal irradiation with > 50 Gy showed no profound cognitive decline in this series.

Long-term survival with IDH wildtype glioblastoma: first results from the ETERNITY Brain Tumor Funders' Collaborative Consortium (EORTC 1419).

BACKGROUND: Median survival with glioblastoma remains in the range of 12 months on population levels. Only few patients survive for more than 5 years. Patient and disease features associated with long-term survival remain poorly defined. METHODS: European Organization for Research and Treatment of Cancer (EORTC) 1419 (ETERNITY) is a registry study supported by the Brain Tumor Funders Collaborative in the US and the EORTC Brain Tumor Group. Patients with glioblastoma surviving at least 5 years from diagnosis were identified at 24 sites in Europe, US, and Australia. In patients with isocitrate dehydrogenase (IDH) wildtype tumours, prognostic factors were analysed using the Kaplan-Meier method and the Cox proportional hazards model. A population-based reference cohort was obtained from the Cantonal cancer registry Zurich. RESULTS: At the database lock of July 2020, 280 patients with histologically centrally confirmed glioblastoma (189 IDH wildtype, 80 IDH mutant, 11 incompletely characterised) had been registered. In the IDH wildtype population, median age was 56 years (range 24-78 years), 96 patients (50.8%) were female, 139 patients (74.3%) had tumours with O6-methylguanine DNA methyltransferase (MGMT) promoter methylation. Median overall survival was 9.9 years (95% confidence interval [95% CI] 7.9-11.9). Patients without recurrence experienced longer median survival (not reached) than patients with one or more recurrences (8.92 years) (p < 0.001) and had a high rate (48.8%) of MGMT promoter-unmethylated tumours. CONCLUSIONS: Freedom from progression is a powerful predictor of overall survival in long-term survivors with glioblastoma. Patients without relapse often have MGMT promoter-unmethylated glioblastoma and may represent a distinct subtype of glioblastoma.

Aurora B Kinase Inhibition by AZD1152 Concomitant with Tumor Treating Fields Is Effective in the Treatment of Cultures from Primary and Recurrent Glioblastomas.

Tumor Treating Fields (TTFields) were incorporated into the treatment of glioblastoma, the most malignant brain tumor, after showing an effect on progression-free and overall survival in a phase III clinical trial. The combination of TTFields and an antimitotic drug might further improve this approach. Here, we tested the combination of TTFields with AZD1152, an Aurora B kinase inhibitor, in primary cultures of newly diagnosed (ndGBM) and recurrent glioblastoma (rGBM). AZD1152 concentration was titrated for each cell line and 5-30 nM were used alone or in addition to TTFields (1.6 V/cm RMS; 200 kHz) applied for 72 h using the inovitro™ system. Cell morphological changes were visualized by conventional and confocal laser microscopy. The cytotoxic effects were determined by cell viability assays. Primary cultures of ndGBM and rGBM varied in p53 mutational status; ploidy; EGFR expression and MGMT-promoter methylation status. Nevertheless; in all primary cultures; a significant cytotoxic effect was found following TTFields treatment alone and in all but one, a significant effect after treatment with AZD1152 alone was also observed. Moreover, in all primary cultures the combined treatment had the most pronounced cytotoxic effect in parallel with morphological changes. The combined treatment of TTFields and AZD1152 led to a significant reduction in the number of ndGBM and rGBM cells compared to each treatment alone. Further evaluation of this approach, which has to be considered as a proof of concept, is warranted, before entering into early clinical trials.

Association of Autologous Tumor Lysate-Loaded Dendritic Cell Vaccination With Extension of Survival Among Patients With Newly Diagnosed and Recurrent Glioblastoma: A Phase 3 Prospective Externally Controlled Cohort Trial.

Importance: Glioblastoma is the most lethal primary brain cancer. Clinical outcomes for glioblastoma remain poor, and new treatments are needed. Objective: To investigate whether adding autologous tumor lysate-loaded dendritic cell vaccine (DCVax-L) to standard of care (SOC) extends survival among patients with glioblastoma. Design, Setting, and Participants: This phase 3, prospective, externally controlled nonrandomized trial compared overall survival (OS) in patients with newly diagnosed glioblastoma (nGBM) and recurrent glioblastoma (rGBM) treated with DCVax-L plus SOC vs contemporaneous matched external control patients treated with SOC. This international, multicenter trial was conducted at 94 sites in 4 countries from August 2007 to November 2015. Data analysis was conducted from October 2020 to September 2021. Interventions: The active treatment was DCVax-L plus SOC temozolomide. The nGBM external control patients received SOC temozolomide and placebo; the rGBM external controls received approved rGBM therapies. Main Outcomes and Measures: The primary and secondary end points compared overall survival (OS) in nGBM and rGBM, respectively, with contemporaneous matched external control populations from the control groups of other formal randomized clinical trials. Results: A total of 331 patients were enrolled in the trial, with 232 randomized to the DCVax-L group and 99 to the placebo group. Median OS (mOS) for the 232 patients with nGBM receiving DCVax-L was 19.3 (95% CI, 17.5-21.3) months from randomization (22.4 months from surgery) vs 16.5 (95% CI, 16.0-17.5) months from randomization in control patients (HR = 0.80; 98% CI, 0.00-0.94; P = .002). Survival at 48 months from randomization was 15.7% vs 9.9%, and at 60 months, it was 13.0% vs 5.7%. For 64 patients with rGBM receiving DCVax-L, mOS was 13.2 (95% CI, 9.7-16.8) months from relapse vs 7.8 (95% CI, 7.2-8.2) months among control patients (HR, 0.58; 98% CI, 0.00-0.76; P < .001). Survival at 24 and 30 months after recurrence was 20.7% vs 9.6% and 11.1% vs 5.1%, respectively. Survival was improved in patients with nGBM with methylated MGMT receiving DCVax-L compared with external control patients (HR, 0.74; 98% CI, 0.55-1.00; P = .03). Conclusions and Relevance: In this study, adding DCVax-L to SOC resulted in clinically meaningful and statistically significant extension of survival for patients with both nGBM and rGBM compared with contemporaneous, matched external controls who received SOC alone. Trial Registration: ClinicalTrials.gov Identifier: NCT00045968.

Mid-term treatment-related cognitive sequelae in glioma patients.

PURPOSE: Cognitive functioning represents an essential determinant of quality of life. Since significant advances in neuro-oncological treatment have led to prolonged survival it is important to reliably identify possible treatment-related neurocognitive dysfunction in brain tumor patients. Therefore, the present study specifically evaluates the effects of standard treatment modalities on neurocognitive functions in glioma patients within two years after surgery. METHODS: Eighty-six patients with World Health Organization (WHO) grade 1-4 gliomas were treated between 2004 and 2012 and prospectively followed within the German Glioma Network. They received serial neuropsychological assessment of attention, memory and executive functions using the computer-based test battery NeuroCog FX. As the primary outcome the extent of change in cognitive performance over time was compared between patients who received radiotherapy, chemotherapy or combined radio-chemotherapy and patients without any adjuvant therapy. Additionally, the effect of irradiation and chemotherapy was assessed in subgroup analyses. Furthermore, the potential impact of the extent of tumor resection and histopathological characteristics on cognitive functioning were referred to as secondary outcomes. RESULTS: After a median of 16.8 (range 5.9-31.1) months between post-surgery baseline neuropsychological assessment and follow-up assessment, all treatment groups showed numerical and often even statistically significant improvement in all cognitive domains. The extent of change in cognitive functioning showed no difference between treatment groups. Concerning figural memory only, irradiated patients showed less improvement than non-irradiated patients (p = 0.029, η2 = 0.06). Resected patients, yet not patients with biopsy, showed improvement in all cognitive domains. Compared to patients with astrocytomas, patients with oligodendrogliomas revealed a greater potential to improve in attentional and executive functions. However, the heterogeneity of the patient group and the potentially selected cohort may confound results. CONCLUSION: Within a two-year post-surgery interval, radiotherapy, chemotherapy or their combination as standard treatment did not have a detrimental effect on cognitive functions in WHO grade 1-4 glioma patients. Cognitive performance in patients with adjuvant treatment was comparable to that of patients without.

Prognostic impact of obesity in newly-diagnosed glioblastoma: a secondary analysis of CeTeG/NOA-09 and GLARIUS.

PURPOSE: The role of obesity in glioblastoma remains unclear, as previous analyses have reported contradicting results. Here, we evaluate the prognostic impact of obesity in two trial populations; CeTeG/NOA-09 (n = 129) for MGMT methylated glioblastoma patients comparing temozolomide (TMZ) to lomustine/TMZ, and GLARIUS (n = 170) for MGMT unmethylated glioblastoma patients comparing TMZ to bevacizumab/irinotecan, both in addition to surgery and radiotherapy. METHODS: The impact of obesity (BMI ≥ 30 kg/m2) on overall survival (OS) and progression-free survival (PFS) was investigated with Kaplan-Meier analysis and log-rank tests. A multivariable Cox regression analysis was performed including known prognostic factors as covariables. RESULTS: Overall, 22.6% of patients (67 of 297) were obese. Obesity was associated with shorter survival in patients with MGMT methylated glioblastoma (median OS 22.9 (95% CI 17.7-30.8) vs. 43.2 (32.5-54.4) months for obese and non-obese patients respectively, p = 0.001), but not in MGMT unmethylated glioblastoma (median OS 17.1 (15.8-18.9) vs 17.6 (14.7-20.8) months, p = 0.26). The prognostic impact of obesity in MGMT methylated glioblastoma was confirmed in a multivariable Cox regression (adjusted odds ratio: 2.57 (95% CI 1.53-4.31), p < 0.001) adjusted for age, sex, extent of resection, baseline steroids, Karnofsky performance score, and treatment arm. CONCLUSION: Obesity was associated with shorter survival in MGMT methylated, but not in MGMT unmethylated glioblastoma patients.

Phase I/II trial of meclofenamate in progressive MGMT-methylated glioblastoma under temozolomide second-line therapy-the MecMeth/NOA-24 trial.

BACKGROUND: Glioblastoma is the most frequent and malignant primary brain tumor. Even in the subgroup with O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation and favorable response to first-line therapy, survival after relapse is short (12 months). Standard therapy for recurrent MGMT-methylated glioblastoma is not standardized and may consist of re-resection, re-irradiation, and chemotherapy with temozolomide (TMZ), lomustine (CCNU), or a combination thereof. Preclinical results show that meclofenamate (MFA), originally developed as a nonsteroidal anti-inflammatory drug (NSAID) and registered in the USA, sensitizes glioblastoma cells to temozolomide-induced toxicity via inhibition of gap junction-mediated intercellular cytosolic traffic and demolishment of tumor microtube (TM)-based network morphology. METHODS: In this study, combined MFA/TMZ therapy will be administered (orally) in patients with first relapse of MGMT-methylated glioblastoma. A phase I component (6-12 patients, 2 dose levels of MFA + standard dose TMZ) evaluates safety and feasibility and determines the dose for the randomized phase II component (2 × 30 patients) with progression-free survival as the primary endpoint. DISCUSSION: This study is set up to assess toxicity and first indications of efficacy of MFA repurposed in the setting of a very difficult-to-treat recurrent tumor. The trial is a logical next step after the identification of the role of resistance-providing TMs in glioblastoma, and results will be crucial for further trials targeting TMs. In case of favorable results, MFA may constitute the first clinically feasible TM-targeted drug and therefore might bridge the idea of a TM-targeted therapeutic approach from basic insights into clinical reality. TRIAL REGISTRATION: EudraCT 2021-000708-39 . Registered on 08 February 2021.

Improved efficiency of patient admission with electronic health records in neurosurgery.

BACKGROUND: Electronic health records (EHRs) may be controversial but they have the potential to improve patient care. We investigated whether the introduction of an electronic template-based admission form for the collection of information about the patient's medical history and neurological and clinical state at admission in the neurosurgical unit might have an impact on the quality of documentation in a discharge record and the amount of time taken to produce this documentation. METHOD: A new digital template-based admission form (EHR) was developed and assessed with QNOTE, an assessment tool of medical notes with standardised criteria and the possibility to benchmark the quality of documentations. This was compared to 30 prior paper-based handwritten documentations (HWD) regarding the utilisation of these medical notes for dictation of medical discharge records. RESULTS: Implementation of the EHR significantly improved the quality of patient admission documentation with a QNOTE mean grand score of 87 ± 22 (p < 0.0001) compared to prior HWD with 44 ± 30. The mean documentation time for HWD was 8.1 min ± 4.1 min and the dictation time for discharge records was 10.6 min ± 3.5 min. After implementation of EHR, the documentation time increased slightly to 9.6 min ± 2.3 min (n.s.), while the time for dictation of discharge records was reduced to 5.1 min ± 1.2 min (p < 0.0001). There was a clear correlation between a higher quality of documentation and a higher needed documentation time as well as higher quality of documentation and lower dictation times of discharge records. CONCLUSION: Implementation of the EHR improved the quality of patient admission documentation and reduced the dictation time of discharge records. IMPLICATIONS: It is crucial to involve stakeholders and users of EHRs in a timely manner during the stage of development and implementation phase to ensure optimal results and better usability.

A vaccine targeting mutant IDH1 in newly diagnosed glioma.

Mutated isocitrate dehydrogenase 1 (IDH1) defines a molecularly distinct subtype of diffuse glioma1-3. The most common IDH1 mutation in gliomas affects codon 132 and encodes IDH1(R132H), which harbours a shared clonal neoepitope that is presented on major histocompatibility complex (MHC) class II4,5. An IDH1(R132H)-specific peptide vaccine (IDH1-vac) induces specific therapeutic T helper cell responses that are effective against IDH1(R132H)+ tumours in syngeneic MHC-humanized mice4,6-8. Here we describe a multicentre, single-arm, open-label, first-in-humans phase I trial that we carried out in 33 patients with newly diagnosed World Health Organization grade 3 and 4 IDH1(R132H)+ astrocytomas (Neurooncology Working Group of the German Cancer Society trial 16 (NOA16), ClinicalTrials.gov identifier NCT02454634). The trial met its primary safety endpoint, with vaccine-related adverse events restricted to grade 1. Vaccine-induced immune responses were observed in 93.3% of patients across multiple MHC alleles. Three-year progression-free and death-free rates were 0.63 and 0.84, respectively. Patients with immune responses showed a two-year progression-free rate of 0.82. Two patients without an immune response showed tumour progression within two years of first diagnosis. A mutation-specificity score that incorporates the duration and level of vaccine-induced IDH1(R132H)-specific T cell responses was associated with intratumoral presentation of the IDH1(R132H) neoantigen in pre-treatment tumour tissue. There was a high frequency of pseudoprogression, which indicates intratumoral inflammatory reactions. Pseudoprogression was associated with increased vaccine-induced peripheral T cell responses. Combined single-cell RNA and T cell receptor sequencing showed that tumour-infiltrating CD40LG+ and CXCL13+ T helper cell clusters in a patient with pseudoprogression were dominated by a single IDH1(R132H)-reactive T cell receptor.

Telomerase reverse transcriptase promoter mutation- and O6-methylguanine DNA methyltransferase promoter methylation-mediated sensitivity to temozolomide in isocitrate dehydrogenase-wild-type glioblastoma: is there a link?

AIM OF THE STUDY: Benefit from temozolomide (TMZ) chemotherapy in the treatment of isocitrate dehydrogenase (IDH)-wild-type glioblastoma is essentially limited to patients with O6-methylguanine DNA methyltransferase (MGMT) promoter-methylated tumours. Recent studies suggested that telomerase reverse transcriptase (TERT) promoter hotspot mutations may have an impact on the prognostic role of the MGMT status in patients with glioblastoma. METHODS: MGMT promoter methylation and TERT promoter mutation status were retrospectively assessed in a prospective cohort of patients with IDH-wild-type glioblastoma of the German Glioma Network (GGN) (n = 298) and an independent retrospective cohort from Düsseldorf, Germany, and Zurich, Switzerland (n = 302). RESULTS: In the GGN cohort, but not in the Düsseldorf/Zurich cohort, TERT promoter mutation was moderately associated with inferior outcomes in patients with MGMT promoter-unmethylated tumours (hazard ratio 1.74; 95% confidence interval: 1.07-2.82; p = 0.026). TERT promoter mutations were not associated with better outcomes in patients with MGMT promoter-methylated tumours in either cohort. The two different TERT promoter hotspot mutations (C228T and C250T) were not linked to distinct outcomes. CONCLUSIONS: Analysis of two independent cohorts of patients with glioblastoma did not confirm previous data, suggesting that TERT promoter mutations confer an enhanced benefit from TMZ in patients with MGMT promoter-methylated glioblastoma. Thus, diagnostic testing for TERT promoter mutations may not be required for prediction of TMZ sensitivity in patients with IDH-wild-type glioblastoma.

Final Results of the Prospective Biomarker Trial PETra: [11C]-MET-Accumulation in Postoperative PET/MRI Predicts Outcome after Radiochemotherapy in Glioblastoma.

PURPOSE: This prospective trial investigates the association of time to recurrence (TTR) in glioblastoma with [11C]methionine (MET) tracer uptake before postoperative radiochemotherapy (RCT) aiming to guide radiotherapy boost regions. EXPERIMENTAL DESIGN: Between 2013 and 2016, 102 patients with glioblastoma were recruited. RCT was performed with concurrent and adjuvant temozolomide to a total dose of 60 Gy. Tumor residues in postresection PET and MRI were together defined as gross tumor volumes for radiotherapy treatment planning. [11C]methionine (MET)-PET/MRI was performed before RCT and at each follow-up. RESULTS: The primary hypothesis of a longer TTR for patients without increased tracer accumulation in postoperative MET-PET was confirmed in 89 patients. With 18.9 months (95% confidence interval, 9.3-28.5 months), median TTR was significantly (P < 0.001) longer for patients without (n = 29, 32.6%) as compared with 6.3 months (3.6-8.9) for patients with MET accumulation (n = 60, 67.4%) in pre-RCT PET. Although MRI often did not detect all PET-positive regions, an unfavorable impact of residual tumor in postsurgical MRI (n = 38, 42.7%) on TTR was observed [4.6 (4.2-5.1) vs. 15.5 months (6.0-24.9), P < 0.001]. Significant multivariable predictors for TTR were MRI positivity, PET-positive volume, and O6-methylguanine DNA methyltransferase (MGMT) hypermethylation. CONCLUSIONS: Postsurgical amino acid PET has prognostic value for TTR after RCT in glioblastoma. Because of the added value of the metabolic beyond the pure structural information, it should complement MRI in radiotherapy planning if available with reasonable effort, at least in the context of maximal therapy. Furthermore, the spatial correlation of regions of recurrence with PET-positive volumes could provide a bioimaging basis for further trials, for example, testing local radiation dose escalation.

MGMT promoter methylation analysis for allocating combined CCNU/TMZ chemotherapy: Lessons learned from the CeTeG/NOA-09 trial.

The CeTeG/NOA-09 trial showed a survival benefit for combined CCNU/TMZ therapy in MGMT-promoter-methylated glioblastoma patients (quantitative methylation-specific PCR [qMSP] ratio > 2). Here, we report on the prognostic value of the MGMT promoter methylation ratio determined by qMSP and evaluate the concordance of MGMT methylation results obtained by qMSP, pyrosequencing (PSQ) or DNA methylation arrays (MGMT-STP27). A potential association of qMSP ratio with survival was analyzed in the CeTeG/NOA-09 trial population (n = 129; log-rank tests, Cox regression analyses). The concordance of MGMT methylation assays (qMSP, PSQ and MGMT-STP27) was evaluated in 76 screened patients. Patients with tumors of qMSP ratio > 4 showed superior survival compared to those with ratios 2-4 (P = .0251, log-rank test). In multivariate analysis, the qMSP ratio was not prognostic across the study cohort (hazard ratio [HR] = 0.88; 95% CI: 0.72-1.08). With different cutoffs for qMSP ratio (4, 9, 12 or 25), the CCNU/TMZ benefit tended to be larger in subgroups with lower ratios (eg, for cutoff 9: HR 0.32 for lower subgroup, 0.73 for higher subgroup). The concordance rates with qMSP were 94.4% (PSQ) and 90.2% (MGMT-STP27). Discordant results were restricted to tumors with qMSP ratios ≤4 and PSQ mean methylation rate ≤25%. Despite a shorter survival in MGMT-promoter-methylated patients with lower methylation according to qMSP, these patients had a benefit from combined CCNU/TMZ therapy, which even tended to be stronger than in patients with higher methylation rates. With acceptable concordance rates, decisions on CCNU/TMZ therapy may also be based on PSQ or MGMT-STP27.

Exome sequencing identifies frequent genomic loss of TET1 in IDH-wild-type glioblastoma.

Glioblastoma (GBM) is the most common and malignant brain tumor in adults. Genomic and epigenomic alterations of multiple cancer-driving genes are frequent in GBM. To identify molecular alterations associated with epigenetic aberrations, we performed whole exome sequencing-based analysis of DNA copy number variations in 55 adult patients with IDH-wild-type GBM. Beside mutations in common GBM driver genes such as TERTp (76%), TP53 (22%) and PTEN (20%), 67% of patients were affected by amplifications of genes associated with RTK/Rb/p53 cell signaling, including EGFR (45%), CDK4 (13%), and MDM2/4 (both 7%). The minimal deleted region at chromosome 10 was detected at the DNA demethylase TET1 (93%), mainly due to a loss-of-heterozygosity of complete chromosome 10 (53%) or by a mono-allelic microdeletion at 10q21.3 (7%). In addition, bi-allelic TET1 deletions, detected in 18 patients (33%), frequently co-occurred with EGFR amplification and were associated with low levels of TET1 mRNA expression, pointing at loss of TET1 activity. Bi-allelic TET1 loss was not associated with global concentrations of 5-hydroxymethylcytosine, indicating a site-specific effect of TET1 for DNA (de)methylation. Focal amplification of EGFR positively correlated with overall mutational burden, tumor size, and poor long-term survival. Bi-allelic TET1 loss was not an independent prognostic factor, but significantly associated with poor survival in patients with concomitant EGFR amplification. Rates of genomic TET1 deletion were significantly lower in a cohort of IDH1-mutated patients. Despite the relevance of TET1 for DNA demethylation and as potential therapeutic target, a frequent genomic loss of TET1 has not previously been reported in GBM.

Melanoma brain metastases - Interdisciplinary management recommendations 2020.

Melanoma brain metastases (MBM) are common and associated with a particularly poor prognosis; they directly cause death in 60-70% of melanoma patients. In the past, systemic treatments have shown response rates around 5%, whole brain radiation as standard of care has achieved a median overall survival of approximately three months. Recently, the combination of immune checkpoint inhibitors and combinations of MAP-kinase inhibitors both have shown very promising response rates of up to 55% and 58%, respectively, and improved survival. However, current clinical evidence is based on multi-cohort studies only, as prospectively randomized trials have been carried out rarely in MBM, independently whether investigating systemic therapy, radiotherapy or surgical techniques. Here, an interdisciplinary expert team reviewed the outcome of prospectively conducted clinical studies in MBM, identified evidence gaps and provided recommendations for the diagnosis, treatment, outcome evaluation and monitoring of MBM patients. The recommendations refer to four distinct scenarios: patients (i) with 'brain-only' disease, (ii) with oligometastatic asymptomatic intra- and extracranial disease, (iii) with multiple asymptomatic metastases, and (iv) with multiple symptomatic MBM or leptomeningeal disease. Changes in current management recommendations comprise the use of immunotherapy - preferably combined anti-CTLA-4/PD-1-immunotherapy - in asymptomatic MBM minus/plus stereotactic radiosurgery which remains the mainstay of local brain therapy being safe and effective. Adjuvant whole-brain radiotherapy provides no clinical benefit in oligometastatic MBM. Among the systemic therapies, combined MAPK-kinase inhibition provides, in BRAFV600-mutated patients with rapidly progressing or/and symptomatic MBM, an alternative to combined immunotherapy.

Label-free multiphoton microscopy as a tool to investigate alterations of cerebral aneurysms.

Cerebral aneurysms are abnormal focal dilatations of arterial vessel walls with pathological vessel structure alterations. Sudden rupture can lead to a subarachnoid hemorrhage, which is associated with a high mortality. Therefore, the origin of cerebral aneurysms as well as the progression to the point of rupture needs to be further investigated. Label-free multimodal multiphoton microscopy (MPM) was performed on resected human aneurysm domes and integrated three modalities: coherent anti-Stokes Raman scattering, endogenous two-photon fluorescence and second harmonic generation. We showed that MPM is a completely label-free and real-time powerful tool to detect pathognomonic histopathological changes in aneurysms, e.g. thickening and thinning of vessel walls, intimal hyperplasia, intra-wall haemorrhage, calcification as well as atherosclerotic changes. In particular, the loss or fragmentation of elastin as well as fibromatous wall remodelling appeared very distinct. Remarkably, cholesterol and lipid deposits were clearly visible in the multiphoton images. MPM provides morphological and biochemical information that are crucial for understanding the mechanisms of aneurysm formation and progression.

Establishment and Characterisation of Heterotopic Patient-Derived Xenografts for Glioblastoma.

Glioblastoma is an aggressive brain tumour with a patient median survival of approximately 14 months. The development of innovative treatment strategies to increase the life span and quality of life of patients is hence essential. This requires the use of appropriate glioblastoma models for preclinical testing, which faithfully reflect human cancers. The aim of this study was to establish glioblastoma patient-derived xenografts (PDXs) by heterotopic transplantation of tumour pieces in the axillae of NMRI nude mice. Ten out of 22 patients' samples gave rise to tumours in mice. Their human origin was confirmed by microsatellite analyses, though minor changes were observed. The glioblastoma nature of the PDXs was corroborated by pathological evaluation. Latency times spanned from 48.5 to 370.5 days in the first generation. Growth curve analyses revealed an increase in the growth rate with increasing passages. The methylation status of the MGMT promoter in the primary material was maintained in the PDXs. However, a trend towards a more methylated pattern could be found. A correlation was observed between the take in mice and the proportion of Sox2+ cells (r = 0.49, p = 0.016) and nestin+ cells (r = 0.55, p = 0.007). Our results show that many PDXs maintain key features of the patients' samples they derive from. They could thus be used as preclinical models to test new therapies and biomarkers.