Desmoplastic trichoepithelioma with nevus cell nevi

Among a total of 270,000 skin biopsies, 87 desmoplastic trichoepitheliomas were identified, 11 (12.6%) of which were associated with nevocytic nevi. Histopathologically we found nevocytes next to horn cysts and thin strands of monomorphous basaloid neoplastic cells in a dense desmoplastic stroma. The frequency of this association suggests that it may be a combined malformation rather than a chance occurrence. On clinical examination most cases had been misdiagnosed as basal cell carcinomas. Most biopsies were taken from the faces of fairly young women.