Oncogenic extrachromosomal DNA identification using whole-genome sequencing from formalin-fixed glioblastomas

Glioblastoma, an area of urgent unmet clinical need, is the most common intrinsic brain cancer and frequently contains extrachromosomal DNA (ecDNA). EcDNA is increasingly recognized as a driver of cancer evolution and a mediator of therapy resistance1,2. Recent studies have implicated ecDNA as a prognostic marker across many cancer types, and a driver of glioblastoma, with emerging clinical trials aiming to leverage knowledge of ecDNA status or therapeutically target ecDNA directly3.