Fig. 2.

CCH, dog. (a) Intra-epidermal nests of neoplastic cells (arrows). HE. (b) Neoplastic histiocytoma cells accompanied by diffuse T-lymphocytes (CD3+). Immunoperoxidase stain; DAB substrate; Mayer’s haematoxylin counterstain. (c) Neoplastic histiocytoma cells showing diffuse cytoplasmic MHCII expression. Immunoperoxidase stain; DAB substrate; Mayer’s haematoxylin counterstain. (d) Expression of E-cadherin in tumour cells, with strong expression in the subepidermal area of the tumour that gradually decreased in the deeper parts of the tumour. Immunoperoxidase stain; DAB substrate; Mayer’s haematoxylin counterstain