case_images: PMC4296274_01
case_images: 80-year-old man with primary pleural lymphoma (marginal zone B-cell lymphoma).. A. Contrast-enhanced CT showing pleural effusion and diffuse homogeneous pleural mass invading into extrapleural space in right hemithorax. Intercostal artery is enveloped by parietal pleural and extrapleural masses, demonstrating sandwich sign (arrows). B. F-18-fluorodeoxyglucose positron emission tomography showing diffuse hypermetabolism in right pleural mass. C. Pleural biopsy revealing diffuse infiltration of small to medium-sized lymphoid cells with scant to moderate amount of clear cytoplasm which is consistent with marginal zone B-cell lymphoma (hematoxylin and eosin stain, 400 x magnification).
case_images: kjr-16-213-g001.jpg
case_images: PMC4296274_01_kjr-16-213-g001.jpg
case_images: F1
case_images: The intercostal arteries enveloped by the mass were well visualized on axial CT images showing the sandwich sign (Fig. 1A). F-18-fluorodeoxyglucose positron emission tomography (FDG-PET) showed hypermetabolism in the right pleural mass (Fig. 1B). Histopathological and immuno-histochemical examinations revealed monotonous infiltration of small B-cells expressing CD-20 antigen (Fig. 1C).
case_images: PMC4296274_02
case_images: Sandwich sign in 68-year-old man with primary pleural lymphoma (diffuse large B-cell lymphoma).. A. Axial image of contrast-enhanced CT showing right pleural effusion and diffuse pleural mass extending into extrapleural space and paraspinal region. Sandwiching of intercostal artery by conglomerated pleural and extrapleural masses is noted by arrows. B. Pleural fluid cell block specimen showing numerous large atypical lymphoid cells (hematoxylin and eosin stain, x 400 magnification).
case_images: kjr-16-213-g002.jpg
case_images: PMC4296274_02_kjr-16-213-g002.jpg
case_images: F2
case_images: It invaded into the extrapleural space with encasement of the intercostal arteries, demonstrating a sandwich sign (Fig. 2A). Cytological examination of the pleural fluid showed many large atypical lymphoid cells (Fig. 2B).