Contributed by Lin Liu, MD, PhD and Sara E Monaco, MD
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An 81-year-old man with a previous history of lymphoma and a gastric mass presented with multiple liver masses. Ultrasound-Guided FNA of a liver mass was performed with on-site cytopathology evaluation (Figures 1-4).
Figure 1 (Diff-Quik stain; Left. x200 magnification; Right. x400 magnification)
Figure 2 (Diff-Quik stain; x400 magnification)
Figure 3 (Papanicolaou stain, x400 magnification)
Figure 4 (H&E, Pankeratin and C-Kit stains of the cell block)
Cytological examination of the aspirate smears from the liver fine needle aspiration (FNA) are cellular and demonstrate loosely cohesive and discohesive epithelioid cells, in a background of benign hepatocytes (Figures 1, 2 and 3). These cells have moderate nuclear pleomorphism, increased nuclear-to-cytoplasmic ratios, and moderate amounts of dense-to-glassy cytoplasm. In addition, there is a conspicuous presence of metachromatic extracellular material intermingled with the cells on the aspirate smears, and most easily visualized on the air-dried Diff-Quik stained smears (Figure 2).
Immunohistochemical stains revealed that the tumor cells are positive for CD117/c-Kit (Figure 4), and negative for Pan-cytokeratin (Figure 4), Vimentin, Smooth muscle actin, S100 and CD34.