Key points are not available for this paper at this time.
• The main factors that impact glioma overall and diffuse lower-grade glioma incidences are reviewed. • Estimate of the 2024 French glioma incidence is 6.6/100,000 person-years. • For the first time we provided incidence and prevalence estimates of diffuse IDH-mutant glioma in France. • French incidence estimates of diffuse IDH-mutant gliomas are 1/0.5/0.3/0.2, for all grade (g), g2, g3, g4 /100,000 p-y, respectively. • Grade 2 IDH-mutant glioma prevalence would be greater than 6.57/100,000 persons. The recent advent of anti-IDH therapies and changes in the WHO classification of gliomas implies estimating the number of patients who could benefit (or not) from anti-IDH treatment. As published data on the current incidence of different subtypes of IDH-mutant gliomas (based on the latest histomolecular WHO classification) are lacking in many countries. The present analysis aims to review the main factors impacting the incidence of gliomas and lower-grade gliomas and to estimate the incidence and prevalence of IDH-mutant gliomas in France. Our analysis was based on data from the French Brain Tumor DataBase and literature. Case definition, recording methods, histological classifications, age, sex, ethnicity, ancestry, environment, genetics, etc., impact the incidence of gliomas overall and lower-grade gliomas. In France, for the year 2024, the incidence estimates of all gliomas and all adult-type diffuse IDH-mutant gliomas are 6.6/100,000 and 1/100,000 person-years, respectively. The incidence estimates of grades 2, 3, and 4 diffuse IDH-mutant gliomas are 0.5, 0.3, 0.2 per 100,000 person-years, respectively. Of note, the incidence estimate of grade 3 diffuse IDH-mutant glioma versus grade 2 or 4 is slightly more difficult to assess due to the possible variability in histological criteria to define tumor grade. The prevalence of diffuse IDH-mutant grade 2 glioma would be more than 6.57/100,000 persons. Our epidemiological analysis provides estimates of potential number of patients, but large prospective real-world studies are required to determine the positioning of anti-IDH treatments among all therapeutic strategies surgery(ies), chemotherapy(ies), radiotherapy(ies), clinical/radiological follow-up, etc..
Bauchet et al. (Fri,) studied this question.