97 IOS Press MGMT methylation status: The advent of stratified therapy in glioblastoma?

Abstract. Glioblastomas are the most malignant gliomas with median survival times of only 15 months despite modern therapies. All standard treatments are palliative. Pathogenetic factors are diverse, hence, stratified treatment plans are warranted considering the molecular heterogeneity among these tumors. However, most patients are treated with "one fits all" standard therapies, many of them with minor response and major toxicities. The integration of clinical and molecular information, now becoming available using new tools such as gene arrays, proteomics, and molecular imaging, will take us to an era where more targeted and effective treatments may be implemented. A first step towards the design of such therapies is the identification of relevant molecular mechanisms driving the aggressive biological behavior of glioblastoma. The accumulation of diverse aberrations in regulatory processes enables tumor cells to bypass the effects of most classical therapies available. Molecular alterations underlying such mechanisms comprise aberrations on the genetic level, such as point mutations of distinct genes, or amplifications and deletions, while others result from epigenetic modifications such as aberrant methylation of CpG islands in the regulatory sequence of genes. Epigenetic silencing of the MGMT gene encoding a DNA repair enzyme was recently found to be of predictive value in a randomized clinical trial for newly diagnosed glioblastoma testing the addition of the alkylating agent temozolomide to standard radiotherapy. Determination of the methylation status of the MGMT promoter may become the first molecular diagnostic tool to identify patients most likely to respond that will allow individually tailored therapy in glioblastoma. To date, the test for the MGMT-methylation status is the only tool available that may direct the choice for alkylating agents in glioblastoma patients, but many others may hopefully become part of an arsenal to stratify patients to respective targeted therapies within the next years

Developing an Integrative Treatment Program for Cancer-Related Fatigue Using Stakeholder Engagement – A Qualitative Study

Background: Although cancer-related fatigue (CRF) has gained increased attention in the past decade, it remains difficult to treat. An integrative approach combining conventional and complementary medicine interventions seems highly promising. Treatment programs are more likely to be effective if the needs and interests of the people involved are well represented. This can be achieved through stakeholder engagement. Objectives: The aim of the study was to develop an integrative CRF treatment program using stakeholder engagement and to compare it to an expert version. Method: In a qualitative study, a total of 22 stakeholders (4 oncologists, 1 radiation-oncologist, 1 psycho-oncologist, 5 nurses/nurse experts, 9 patients, 1 patient family member, 1 representative of a local Swiss Cancer League) were interviewed either face-to-face or in a focus group setting. For data analysis, qualitative content analysis was used. Results: With stakeholder engagement, the integrative CRF treatment program was adapted to usual care using a prioritizing approach and allowing more patient choice. Unlike the expert version, in which all intervention options were on the same level, the stakeholder engagement process resulted in a program with 3 different levels. The first level includes mandatory nonpharmacological interventions, the second includes nonpharmacological choice-based interventions, and the third includes pharmacological interventions for severe CRF. The resulting stakeholder based integrative CRF treatment program was implemented as clinical practice guideline at our clinic (Institute for Complementary and Integrative Medicine, University Hospital Zurich). Conclusion: Through the stakeholder engagement approach, we integrated the needs and preferences of people who are directly affected by CRF. This resulted in an integrative CRF treatment program with graded recommendations for interventions and therefore potentially greater sustainability in a usual care setting

MGMT promoter methylation in malignant gliomas: ready for personalized medicine?

The DNA repair enzyme O(6)-methylguanine-DNA methyltransferase (MGMT) antagonizes the genotoxic effects of alkylating agents. MGMT promoter methylation is the key mechanism of MGMT gene silencing and predicts a favorable outcome in patients with glioblastoma who are exposed to alkylating agent chemotherapy. This biomarker is on the verge of entering clinical decision-making and is currently used to stratify or even select glioblastoma patients for clinical trials. In other subtypes of glioma, such as anaplastic gliomas, the relevance of MGMT promoter methylation might extend beyond the prediction of chemosensitivity, and could reflect a distinct molecular profile. Here, we review the most commonly used assays for evaluation of MGMT status, outline the prerequisites for standardized tests, and evaluate reasons for difficulties in reproducibility. We critically discuss the prognostic and predictive value of MGMT silencing, reviewing trials in which patients with different types of glioma were treated with various chemotherapy schedules, either up-front or at recurrence. Standardization of MGMT testing requires comparison of different technologies across laboratories and prospectively validated cut-off values for prognostic or predictive effects. Moreover, future clinical trials will need to determine, for each subtype of glioma, the degree to which MGMT promoter methylation is predictive or prognostic, and whether testing should become routine clinical practice

Feasibility study of 21-day-on/7-day-off temozolomide in children with brain tumors

Temozolomide (TMZ) is an oral alkylating agent with proven antitumoral activity in preclinical and clinical studies in adults with high-grade glioma (HGG). However, only limited efficacy has been reported in children with HGG using the 5-day schedule. This study investigated the safety of administering TMZ to children and adolescents with brain tumors over an extended period. Extended schedules have been proven to overcome chemoresistance without any major toxicity. The toxicity of TMZ, administered at 70 mg/m(2)/day orally for 21 consecutive days every 28 days, was assessed in children with brain tumors. A total of 156 courses of TMZ were given to 17 patients (median age 12.5 years, range 1-17 years), who were recruited into the study. Eleven patients had progressive or relapsing disease, and six patients were newly diagnosed. In this cohort no cases of toxic death or nonhematological toxicity were reported. In comparison with the 5-day schedule, thrombocytopenia and neutropenia were noted to be less frequent. Grades 3 and 4 lymphopenia occurred in 10.8 and 22.4% of courses, respectively; among the lymphopenic patients there was one case of disseminated zoster (meningoencephalitis and cutaneous involvement), one case of rotavirus gastroenteritis, and two cases of herpetic stomatitis reported. The objective response rate was 11.8%. Overall, 82.3% of patients showed stable disease. The prolonged TMZ schedule appeared to be well tolerated, with few cases of neutropenia or thrombocytopenia recorded. Nevertheless, prolonged exposure to TMZ was associated with lymphopenia and may lead to a higher rate of viral infections

Oncolytic DNX-2401 virotherapy plus pembrolizumab in recurrent glioblastoma: a phase 1/2 trial.

Immune-mediated anti-tumoral responses, elicited by oncolytic viruses and augmented with checkpoint inhibition, may be an effective treatment approach for glioblastoma. Here in this multicenter phase 1/2 study we evaluated the combination of intratumoral delivery of oncolytic virus DNX-2401 followed by intravenous anti-PD-1 antibody pembrolizumab in recurrent glioblastoma, first in a dose-escalation and then in a dose-expansion phase, in 49 patients. The primary endpoints were overall safety and objective response rate. The primary safety endpoint was met, whereas the primary efficacy endpoint was not met. There were no dose-limiting toxicities, and full dose combined treatment was well tolerated. The objective response rate was 10.4% (90% confidence interval (CI) 4.2-20.7%), which was not statistically greater than the prespecified control rate of 5%. The secondary endpoint of overall survival at 12 months was 52.7% (95% CI 40.1-69.2%), which was statistically greater than the prespecified control rate of 20%. Median overall survival was 12.5 months (10.7-13.5 months). Objective responses led to longer survival (hazard ratio 0.20, 95% CI 0.05-0.87). A total of 56.2% (95% CI 41.1-70.5%) of patients had a clinical benefit defined as stable disease or better. Three patients completed treatment with durable responses and remain alive at 45, 48 and 60 months. Exploratory mutational, gene-expression and immunophenotypic analyses revealed that the balance between immune cell infiltration and expression of checkpoint inhibitors may potentially inform on response to treatment and mechanisms of resistance. Overall, the combination of intratumoral DNX-2401 followed by pembrolizumab was safe with notable survival benefit in select patients (ClinicalTrials.gov registration: NCT02798406)