DOI: 10.1093/noajnl/vdag263 ISSN: 2632-2498
Sarcomatous transformation of an IDH-mutant oligodendroglioma matching to methylation class oligosarcoma despite vorasidenib use, a case report
Lucy P Evans, Janet La, Matija Snuderl, Vyshak A Venur, Samuel N Emerson, Kristyn GalbraithLay Summary
Oligodendroglioma is a brain tumor that usually grows relatively slowly but can become more aggressive over time. We describe a rare case in which an oligodendroglioma progressed and transformed into oligosarcoma, a recently recognized aggressive tumor type, despite treatment with vorasidenib, a drug targeting the IDH mutation that drives these tumors. Genetic testing confirmed that the transformed tumor remained related to the original cancer while acquiring additional important molecular changes. This case demonstrates that tumor evolution may continue despite targeted IDH therapy and highlights the importance of repeat biopsies and molecular testing when tumors progress or behave in unexpected ways.