J Neuropathol Exp Neurol 2021 Nov 28. Epub 2021 Nov 28.
From the Department of Pediatrics, University of Colorado School of Medicine, Children's Hospital Colorado, Aurora, Colorado, USA (KTL); Department of Pediatrics, University of Colorado School of Medicine, Morgan Adams Foundation Pediatric Brain Tumor Research Program, Aurora, Colorado, USA (HVC, JD, PC, BS, AD, CAE, AJK, ALG); and Department of Pathology, University of Colorado School of Medicine, Aurora, Colorado, USA (KD, NW, AG).
Brain tumors are the most common solid tumor in children, and low-grade gliomas (LGGs) are the most common childhood brain tumor. Here, we report on 3 patients with LGG harboring previously unreported or rarely reported RAF fusions: FYCO1-RAF1, CTTNBP2-BRAF, and SLC44A1-BRAF. We hypothesized that these tumors would show molecular similarity to the canonical KIAA1549-BRAF fusion that is the most widely seen alteration in pilocytic astrocytoma (PA), the most common pediatric LGG variant, and that this similarity would include mitogen-activated protein kinase (MAPK) pathway activation. Read More