VIM and viral infectious disease: Immunohistochemistry showed atypical, subepithelial cells positive for vimentin and negative for leukocyte common antigen, cytokeratins, smooth muscle actin, HHF35, CD68, S100, and cytomegalovirus antibody; these results suggested sarcoma with muscle or histiocytic differentiation, malignant lymphoma, malignant melanoma, and viral infection as unlikely for diagnosis (Figure 2(c); stain: immunohistochemistry with anti-vimentin antibody; original magnification: 400x).