Fig. 2

Biopsies of the PET-CT avid regions indicated scattered Epstein–Barr encoding region (EBER)-positive cells without evidence of lymphoma. a Hematoxylin and eosin (H&E) staining of sinonasal epithelium with underlying dense chronic inflammatory infiltrate, increased vasculature, thickened basement membrane, and increased goblet cells. Germinal center formation was present, with polarization and tingible body macrophages. Lymphoplasmacytic infiltrates were present in the interstitium. There were no areas of necrosis or mass lesions appreciated. b B cells predominately found in germinal centers were highlighted by CD20 positivity. c Increased scattered EBER–in situ hybridization-positive cells were seen as predominately small and stained. (×4 magnification)