[Benign cutaneous fibrohistiocytoma. Morphological analysis of 176 cases].

We report a review of the morphologic and topographic characteristics of 176 cases of cutaneous fibrous histiocytoma. We confirm its prevalence in females with greater incidence of location in the limbs. Among the morphologic varieties the most frequent is the fibro-collagenous.

[Sporadic dysplastic nevus syndrome. ULtrastructural observations].

A case of sporadic dysplastic nevus syndrome is presented, with light and electronic microscopy. The absence of macromelanosomes in the ultrastructural studies of the nevoid lesion supports the nosological identity of the disease (histological marker).

[Basocellular epithelioma. Considerations on its histogenesis].

Twenty-nine cases of basal cell carcinoma were studied with immunoperoxidase techniques for the detection of carcinoembryonic antigen. Results presented in the text would indicate that a high percentage of basal cell carcinomas have sweat gland histogenetic origins and that this is independent of its morphologic features. The use of immunohistochemical techniques in the detection of biological markers demonstrates once again their value not only in identifying a disease but also in determining its histogenetic origins.