case_images: PMC4720802_01
case_images: MRI and histologic findings of 59-year-old woman with immunoglobulin G4 (IgG4)-related sclerosing disease.. A, B. Coronal T1-weighted (A) and T2-weighted (B) MR images demonstrate diffuse enlargement of both palatine tonsils (arrows). Lesion appears isointense on T1-weighted- and slightly hyperintense on T2-weighted-images, as compared with muscle. Note focal asymmetric bulging in right palatine tonsil (arrowheads). C. Axial fat-saturated T2-weighted image reveals striated pattern in bilateral tonsils (arrows). D-G. Microscopic examinations show dense lymphoplasmacytic infiltrate (D, hematoxylin and eosin [H&E], x 40) and storiform fibrosis with lymphoplasmacytic inflammatory infiltration (E, H&E, x 400). Immunochemical studies demonstrate many IgG4-positive plasma cells (> 50/high power field) (F). Ratio of IgG4- (F, x 200) to total IgG- (G, x 200) expressing cells is > 40%.
case_images: kjr-17-147-g001.jpg
case_images: PMC4720802_01_kjr-17-147-g001.jpg
case_images: F1
case_images: Lesions appeared as isointense on T1-weighted (Fig. 1A) and slightly hyperintense on T2-weighted MRI images (Fig. 1B), as compared with muscle. Both palatine tonsils showed a striated pattern on the fat suppressed T2-weighted image (Fig. 1C). 18F-fluorodeoxyglucose positron emission tomography (PET)-CT showed increased uptake at both palatine tonsils with maximum standardized uptake value of 7.9. Histological examination showed dense infiltration of plasma cells with storiform-type fibrosis (IgG4 positive cells > 50/high power field), and a ratio of IgG4-expressing to total IgG-expressing cells of > 40% on immunohistochemistry (Fig. 1D-G).