Somatic mutations in the isocitrate dehydrogenase genes IDH1 and IDH2 occur at high frequency in several tumour types. Even though these mutations are confined to distinct hotspots, we show that... Show moreSomatic mutations in the isocitrate dehydrogenase genes IDH1 and IDH2 occur at high frequency in several tumour types. Even though these mutations are confined to distinct hotspots, we show that gliomas are the only tumour type with an exceptionally high percentage of IDH1(R132H) mutations. Patients harbouring IDH1(R132H) mutated tumours have lower levels of genome-wide DNA-methylation, and an associated increased gene expression, compared to tumours with other IDH1/2 mutations ("non-R132H IDH1/2 mutations"). This reduced methylation is seen in multiple tumour types and thus appears independent of the site of origin. For 1p/19q non-codeleted glioma (astrocytoma) patients, we show that this difference is clinically relevant: in samples of the randomised phase III CATNON trial, patients harbouring tumours with IDH mutations other than IDH1(R132H) have a better outcome (hazard ratio 0.41, 95% CI [0.24, 0.71], p = 0.0013). Such non-R132H IDH1/2-mutated tumours also had a significantly lower proportion of tumours assigned to prognostically poor DNA-methylation classes (p < 0.001). IDH mutation-type was independent in a multivariable model containing known clinical and molecular prognostic factors. To confirm these observations, we validated the prognostic effect of IDH mutation type on a large independent dataset. The observation that non-R132H IDH1/2-mutated astrocytomas have a more favourable prognosis than their IDH1(R132H) mutated counterpart indicates that not all IDH-mutations are identical. This difference is clinically relevant and should be taken into account for patient prognostication. Show less
Simple Summary: Health-related quality of life (HRQoL) is an important outcome in glioma patients, as it reflects the patient's perspective on their functioning and wellbeing through the disease... Show moreSimple Summary: Health-related quality of life (HRQoL) is an important outcome in glioma patients, as it reflects the patient's perspective on their functioning and wellbeing through the disease course. The aim of our systematic review was to provide an overview of how HRQoL data is currently analyzed and interpreted in glioma studies. We found that the number of studies including HRQoL data increased in the past decade, but that assessment and analytical methods were highly variable. Ways to maximize information obtained with HRQoL questionnaires include appropriate and complementary analyses at both the group and individual level, comprehensive reporting of HRQoL results, and adherence to existing guidelines on the assessment, analysis, reporting and interpretation of patient-reported outcomes. This may ultimately result in high quality information that is relevant to inform physicians, patients and their relatives about the impact of the disease and its treatment on the patients' functioning and well-being.Background: Health-related quality of life (HRQoL) has become an increasingly important patient-reported outcome in glioma studies. Ideally, collected HRQoL data should be exploited to the full, with proper analytical methods. This systematic review aimed to provide an overview on how HRQoL data is currently evaluated in glioma studies, focusing on the research objectives and statistical analyses of HRQoL data. Methods: A systematic literature search in the databases PubMed, Embase, Web of Science and Cochrane was conducted up to 5 June 2020. Articles were selected based on predetermined inclusion criteria and information on study design, HRQoL instrument, HRQoL research objective and statistical methods were extracted. Results: A total of 170 articles describing 154 unique studies were eligible, in which 17 different HRQoL instruments were used. HRQoL was the primary outcome in 62% of the included articles, and 51% investigated >= 1 research question with respect to HRQoL, for which various analytical methods were used. In only 42% of the articles analyzing HRQoL results over time, the minimally clinical important difference was reported and interpreted. Eighty-six percent of articles reported HRQoL results at a group level only, and not at the individual patient level. Conclusion: Currently, the assessment and analysis of HRQoL outcomes in glioma studies is highly variable. Opportunities to maximize information obtained with HRQoL data include appropriate and complementary analyses at both the group and individual level, comprehensive reporting of HRQoL results in separate articles or supplementary material, and adherence to existing guidelines about the assessment, analysis and reporting of patient-reported outcomes. Show less
Najafabadi, A.Z.; Meer, P. van der; Boele, F.; Nabuurs, R.; Koekkoek, J.; Lagerwaard, F.; ... ; Peerdeman, S. 2018
