case_images: PMC7170100_01
case_images: High-resolution Computed Tomography (HRCT) shows multiple areas of consolidations, interlobular septal thickenings and ground-glass opacities, defining a peculiar "crazy-paving" pattern.
case_images: SVDLD-34-260-g001.jpg
case_images: PMC7170100_01_SVDLD-34-260-g001.jpg
case_images: F1
case_images: Chest X-rays documented multiple bilateral pulmonary consolidations and a High-Resolution Computed Tomography (HRCT) confirmed the presence of bilateral multiple areas of consolidations with frequent air bronchograms, interlobular septal thickenings and ground-glass opacities (Fig. 1).
case_images: At histology the pulmonary lesion are characterized by a dense and diffuse infiltrate of monomorphic lymphocytes and plasma-cells. The lymphoid population is composed of small lymphocytes with a moderate rim of clear cytoplasm obliterating the alveolar spaces (A). The mucosa of bronchial wall reveal lympho-epithelial lesions strongly indicative of extra-nodal MALT lymphoma (B). At immunohistochemistry, neoplastic cells are diffusely positive for CD20, demonstrating the B-cell phenotype and the clonal nature (CD20 immunohistochemistry, Hematoxylin counterstain, 20X (C). Mitotic activity evaluated with MIB-1/Ki-67 is low (3-5%) (MIB1 immunohistochemistry, Hematoxylin counterstain, 20X (D)
case_images: SVDLD-34-260-g002.jpg
case_images: PMC7170100_01_SVDLD-34-260-g002.jpg
case_images: F2
case_images: At histology, the lung parenchyma showed nodular lesions characterized by an infiltration monomorphic small lymphocites and plasma-cells obliterating the alveolar spaces (Fig. 2A) associated with lymphoepithelial lesions (Fig. 2B). At immunohistochemistry, neoplastic lymphocytes show a B-cell clonal phenotype (CD20 immunohistochemistry, Hematoxylin counterstain, 20X (Fig. 2C)); moreover, stain for MIB1 shows a low proliferative index of the neoplastic infiltrate (MIB1 immunohistochemistry, Hematoxylin counterstain, 20X (Fig. 2D)) accounting for 3-5%.