F8Ch44: The cells, forming the whorl near the center of the field, have vacuolated cytoplasm; in addition, there are dyskeratotic features. There is some degree of nuclear pleomorphism.
This lesion is a carcinoma with marked atypia and mitotic activity. It is confined to the dermis on the available sections, but the solid character of the lesion and the uniform degree of atypia are worrisome features. Many of the histologic features can be related to features of tricholemmal differentiation. There are other options, such as clear cell squamous cell carcinoma. A metastasis should also be mentioned in the diagnosis. There are in situ patterns in the neighboring epidermis, but this feature does not entirely exclude metastatic carcinoma.