We report a rare case of @entity957 (SCC) of the cheek skin probably arising from @entity9284 . An 80-year-old @entity1 was referred to our clinic because of a black skin nodule in the right cheek. The nodular lesion was 1 cm in diameter, dome-shaped, hard, sharply demarcated, partially erosive and telangiectatic at the border. The lesion was completely excised under the clinical diagnosis of probable @entity24113 . Microscopically, cutaneous horn and mildly atypical squamous epithelia suggestive of previous @entity9284 were present in the surface of the lesion. The lesion consisted of atypical squamous cells with keratinization and intercellular bridges, and it was regarded as SCC. The SCC cells were seen to invade lightly into the upper dermis, where lymphocytic infiltrations and melanophages were noted. Characteristically, heavy deposition of melanin pigment was recognized in the SCC cells as well as in proliferated dendritic and pigment blockade melanocytes that were scattered or colonized within the SCC cell nests. Masson-Fontana stain revealed numerous melanin granules in the SCC cells, as well as in dendritic and pigment blockade melanocytes. Immunohistochemically, the SCC cells were positive for cytokeratins and epithelial membrane antigen, and negative for @entity4483 protein and HMB45 antigen. Dendritic and pigment blockade melanocytes were negative for cytokeratins, epithelial membrane antigen, and HMB45 antigen, but positive for @entity4483 protein. The present case suggests that SCC cells of the skin may induce proliferation of melanocytes. The differential diagnosis and the histogenesis of pigmented SCC of the skin are discussed.

@entity957 of the cheek skin probably arising from XXXX .

@entity1 :: ('9606', 'Species') :: ['man'] @entity957 :: ('MESH:D002294', 'Disease') :: ['pigmented squamous cell carcinoma'] @entity4483 :: ('6285', 'Gene') :: ['S-100'] @entity9284 :: ('MESH:D007642', 'Disease') :: ['solar keratosis'] @entity24113 :: ('MESH:D017492', 'Disease') :: ['seborrheic keratosis']
@entity9284 :: (MESH:D007642,Disease) :: ['solar keratosis']
