Chondroid syringoma: a histological and immunohistochemical study of 15 cases.

Fifteen cases of chondroid syringoma have been studied histologically and by immunohistochemical methods in an attempt to establish their phenotypic profile and to elucidate their histogenesis. The epithelial elements were classified as tubuloglandular, solid nests and stromal cells. The inner cell layers of tubuloglandular components had distinct epithelial features, expressing cytokeratin, carcino-embryonic antigen and epithelial membrane antigen. The outer cell layers expressed vimentin, S-100 protein, neuron-specific enolase and muscle-specific actin and were negative for epithelial markers. The immunophenotypes of stromal cells and solid nests were similar to those of the outer cell layers. These data suggest that the stromal components may derive from the outer cell of tubuloglandular elements and that myo-epithelial cells have an important role in the histogenesis of these lesions and in their mesenchymal matrix production.