Desmoplastic trichoepithelioma: A clinicopathological study of three cases and a review of the literature.

Desmoplastic trichoepithelioma (DTE) is a rare benign adnexal tumor with the characteristic features of asymptomatic, solitary, annular, indurated and centrally depressed papules or plaques, most commonly occurring in younger individuals on the face. Microscopically and clinically, DTE may be difficult to distinguish from other cutaneous adnexal neoplasms, particularly syringoma, cutaneous metastatic breast cancer, morpheaform basal cell carcinoma and microcystic adnexal carcinoma. The present study reports three cases of DTE. The first case was of a 45-year-old male with an asymptomatic flesh-colored plaque below the right edge of the outer canthus that had been present for seven years. The second case was of a 23-year-old female with an asymptomatic skin lesion on the right cheek that had slowly and progressively increased in size. The third case was of a 26-year-old female who presented with a hard yellowish-white plaque, which gradually grew and formed a rectangular, 3×4-cm patch, on the tip of the left brow. This plaque was present for three years without evident cause or subjective symptoms. In all three cases, the routine systemic examinations and laboratory findings were normal. Histopathological and immunohistochemical findings from incisional biopsies of the lesions were consistent with a diagnosis of DTE. DTE treatment methods and immunohistochemical markers were analyzed by reviewing clinical pathological aspects in order to avoid a misdiagnosis and to provide the best available treatment approach for DTE.