Gliosarcoma (GS) is a rare subtype of glioblastoma (GBM) characterized by both glial and mesenchymal components. Unlike GBM, there are no specific prognostic markers, and optimized treatments for patients with GS do not exist. Recent reports describe BRAF mutation in malignant peripheral nerve sheath tumors, and aberrant Wnt signaling and CTNNB1 (β-catenin gene) mutations have been described in GBM. We sought to determine whether GS tumors harbor BRAF mutations or aberrant Wnt signaling, as indicated by nuclear localization of β-catenin, by immunohistochemical detection. Forty-eight (48) cases of primary and secondary adult GS (including recurrent ones) were evaluated by immunohistochemical techniques for the presence of nuclear β-catenin and the BRAF mutation. A small subset (6/46, 13%) showed nuclear localization of β-catenin. None of the cases harbored BRAF mutations (0/48). These results are the first to describe the presence of Wnt signaling pathway abnormalities, manifested by nuclear β-catenin, in a subset, as well as the lack of BRAF mutation in GS. We propose a potential role for Wnt pathway alterations in the pathogenesis of a subset of GS.
We found 18 patients with immunophenotype consistent with classic hairy cell leukemia (HCL) and BRAF mutations other than just V600E. Twelve had 1 non-V600E BRAF mutation and 6 had V600E with 1 (n=5) or 2 (n=1) non-V600E BRAF co-mutations.
Introduction: BRAFV600E mutation (BRAF) is common in papillary thyroid cancer (PTC), and most patients have an excellent outcome. However, a TERT-promoter mutation (pTERT) in the presence of BRAF (BRAFpTERT) has been demonstrated to confer a more aggressive behavior to PTC. Lymphocytic infiltration is often present in PTC.
Multiple myeloma (MM) remains incurable despite novel therapeutics. A major contributor to the development of relapsed/refractory and resistant MM is extraosseous extramedullary disease (EMD), whose molecular biology is still not fully understood. We analyzed 528 MM patients who presented to our institution between 2014 and 2021 and who had undergone molecular testing.
Pilocytic astrocytomas (PAs) are benign grade 1 gliomas according to the World Health Organization (WHO). They are common in children but rare in adults in whom they may have a worse prognosis. Pediatric PAs are usually associated with dysregulation of the mitogen-activated protein kinase (MAPK) pathway, often involving BRAF alterations such as the KIAA1549::BRAF (K-B) fusion or V600E mutation.
Background: Langerhans cell histiocytosis (LCH) is the most prevalent histiocytic disorder in pediatric populations, with a highly heterogeneous clinical presentation. Currently, the correlation between clinical phenotypes and molecular alterations in childhood LCH, besides the BRAF mutation, has not been sufficiently studied.
Methods: This study presented data on 33 pediatric LCH patients treated at our center who exhibited various molecular alterations other than the BRAF mutation.
