IDH-mutant glioma, a hard-to-treat brain tumour that disproportionately strikes younger adults, has always been defined by the visible mass on the scan. Research led by Professor Kang Seok-gu of Severance Hospital's neurosurgery department with Professor Lee Jeong-ho and Dr Park Jung-won of KAIST, published in Science and announced in January 2026, argues the disease starts much earlier and somewhere else entirely: in surrounding brain tissue that appears, by every conventional measure, normal.
Analysing tumour tissue alongside pathology-confirmed non-tumour cerebral cortex removed during extensive resection surgery, the team found cells carrying IDH mutations within the apparently healthy tissue. These cells bore the hallmarks of glial progenitor cells, the precursors of the brain's supporting cells, suggesting the tumour accumulates over a long period rather than erupting suddenly. Deep gene sequencing and spatial analysis, examining both where cells sit and what they are, underpinned the finding, and introducing the patient-derived genetic alterations into animal models reproduced tumour development.
The implications cut across the treatment pathway: how early such tumours might be detected, how widely surgeons should resect, and what postoperative therapy should target. The work extends a line of enquiry from the same collaboration, whose 2018 Nature study traced glioblastoma to neural stem cells in the subventricular zone, building a picture in which each glioma type has its own cell of origin and birthplace. Severance is now pursuing methods to detect and control the early-stage mutated cells themselves.