Although the co-occurring frequency of MGMT-silencing in the setting of germline MMR deficiency, and the role of MGMT promoter methylation in modulating TMZ sensitivity in pediatric patients is unclear, recent studies suggest that MGMT promoter methylation is common in certain molecular subtypes such as H3.3-G34R and H3K27M wild-type tumors56–59. This evidence concerns the gene MGMT and mismatch repair cancer syndrome 1.