Nuclear β-Catenin Expression is Frequent in Sinonasal Hemangiopericytoma and Its Mimics.
Sinonasal hemangiopericytoma (HPC) is a tumor showing pericytic myoid differentiation and which arises in the nasal cavity and paranasal sinuses. CTNNB1 mutations appear to be a consistent aberration in sinonasal HPC, and nuclear expression of β-catenin has been reported. Our aim was to evaluate the frequency of β-catenin expression in sinonasal HPC and its histologic mimics in the upper aerodigestive tract. Cases were retrieved from the surgical pathology and consultation files. Immunohistochemical staining for β-catenin was performed on 50 soft tissue tumors arising in the sinonasal tract or oral cavity, and nuclear staining was recorded semiquantitatively by extent and intensity. Nuclear reactivity for β-catenin was present in 19/20 cases of sinonasal HPC; 17 showed moderate-to-strong multifocal or diffuse staining, and 2 had moderate focal nuclear reactivity. All solitary fibrous tumors (SFT) (10/10) showed focal-to-multifocal nuclear staining, varying from weak to strong in intensity. Most cases of synovial sarcoma (9/10) showed nuclear β-catenin expression in the spindle cell component, ranging from focal-weak to strong-multifocal. No cases of myopericytoma (0/10) showed any nuclear β-catenin expression. β-catenin expression is prevalent in sinonasal HPC, but is also frequent in SFT and synovial sarcoma. Our findings indicate that β-catenin is not a useful diagnostic tool in the evaluation of spindle cell tumors with a prominent hemangiopericytoma-like vasculature in the sinonasal tract and oral cavity, and that definitive diagnosis relies on the use of a broader immunohistochemical panel.
Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA. vjo@partners.org.
Vickie Y
VY
Jo
Department of Pathology, Brigham and Women's Hospital, Harvard Medical School, 75 Francis Street, Boston, MA, 02115, USA.
Christopher D M
CDM
Fletcher
D014408:Biomarkers, Tumor / Q000032:analysis*; D002467:Cell Nucleus / Q000378:metabolism; D006393:Hemangiopericytoma / Q000175:diagnosis*; D006801:Humans; D009669:Nose Neoplasms / Q000175:diagnosis*; D010255:Paranasal Sinus Neoplasms / Q000175:diagnosis*; D051176:beta Catenin / Q000032:analysis / Q000096:biosynthesis*
D014408:Biomarkers, Tumor; C495270:CTNNB1 protein, human; D051176:beta Catenin
Myopericytoma; Sinonasal; Sinonasal hemangiopericytoma; Soft tissue; Solitary fibrous tumor; Synovial sarcoma; β-Catenin