PMC7511725_01
A) Thorax computerized tomography (CT) showed a heterogeneously enhancing mass-like consolidation in the right anteromedial basal segment of the lung B) Grossly, a white to grey-colored mass, 5.0 x 3.0 x 1.5 cm in size, with central necrosis was identified. C) Microscopically, the tumor was mainly composed of large mononucleated cells and multifocal giant cells. Sheets of neoplastic cells were admixed with an inflammatory component consisting mainly of neutrophils. D) At high magnification, 2 types of giant cells were observed. (arrow: emperipoletic giant cells, block arrow: syncytial shaped-multinucleated giant cells).
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Thorax computerized tomography (CT) identified a heterogeneously enhancing mass-like consolidation in the right anteromedial basal segment of the lung (Fig. 1-A). A white to grey-colored mass, 5.0 x 3.0 x 1.5 cm in size, with central necrosis was identified (Fig. 1-B). Sheets of neoplastic cells were admixed with an inflammatory component consisting mainly of neutrophils (Fig. 1-C). At high magnification, 2 types of giant cells were observed (Fig. 1-D). The first type included the syncytial shaped-multinucleated giant cells showing smudged nuclei and coarsely dispersed chromatin with nuclear molding (Fig. 1-D, block arrow). The multinucleated giant cells showed prominent cytoplasmic cell-in-cell features (Fig. 1-D, arrow).
Immunohistochemically, the tumor cells are positive for pan-cytokeratin (CK) (A), but negative for vimentin (B), TTF-1 (C), and p40 (D). The tumor cells were all positive for SP263 clone (E), SP142 clone (F), and 22C3 clone of PD-L1.
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Immunohistochemical stains revealed that these tumor cells, including giant cells expressed pan-cytokeratin (CK) (Fig. 2-A) while they were negative for vimentin, thyroid transcription factor 1 (TTF-1), and p40 expression (Fig. 2-B, C, and D). In the immunohistochemistry performed for immunotherapy, the tumor cells were all positive for SP263, SP142, and 22C3 clones of programmed death-ligand 1 (PD-L1) (Fig. 2-E, F).