The maximum maxim.

We’ve known pretty much since CT scans were a thing that more complete resections of contrast-enhancing glioblastoma multiforme (GBM) are associated with better outcomes. In 2020 we have a much more sophisticated understanding of the biologic spectrum of GBM, most notably the distinction between IDH-wild type (terrible) and IDH-mutant (less terrible) tumors. This retrospective study with a development cohort treated at UCSF and validation cohorts at Mayo and Cleveland Clinic aimed to determine if this maxim holds true in the era of MRI and IDH-stains. Interestingly, when “complete” resection—defined as no post-op residual contrast-enhanced or non-contrast-enhanced T2-hyperintense tumor—was achieved in patients <65 years old, survival was the similar regardless of IDH status at a median of >3 years. What’s more, this outcome was equally likely across IDH status. TBL: Complete resection of all MR-visualized tumor may outweigh the prognostic implication of IDH status in younger patients with GBM. | Molinaro, JAMA Oncol 2020