DESMOPLASTIC TRICHOEPITHELIOMA AND MULTIPLE EPIDERMAL CYSTS

Abstract

A 22‐year‐old peanut vendor presented with an asympto‐matic annular plaque of 2 years duration on his face. It began as a small, firm papule and gradually increased in size and extent. His occupation involved long hours of ex‐posure to sunshine, but there was no associated burning sensation or irritation.Dermatologic examination revealed an oval, annular plaque over the right temple, about 4 cm × 3 cm. The rim was studded with miliary white papules 1 to 2 mm in size, and the center was depressed (Fig. 1). It had an indurated feel and was freely mobile over the underlying structures. Clinically, a differential diagnosis of colloid milium, granu‐loma annulare, or annular elastolytic granuloma was enter‐tained. In addition, numerous milia were scattered over the cheeks. He also had multiple, well‐defined, firm, white scro‐tal swellings, 1 to 3 cm in size. Systemic examination did not reveal any abnormality.Skin biopsies of the plaque and a scrotal cyst were per‐formed, and the sections stained with hematoxylin and eosin. The annular plaque, showed mild hyperplasia of the epidermis, numerous keratin cysts, islands of basophilic cells in the dermis, and abundant fibrous tissue compress‐ing the tumor cells into narrow strands (Fig. 2). Tumor stro‐mal retraction was conspicuous by its absence. A diagnosis of desmoplastic trichoepithelioma was made.The scrotal nodule revealed an epidermal cyst lined by stratified squamous epithelium and containing laminated keratin (Fig. 3). The patient was referred to the department of plastic surgery, where the plaque was excised in toto, and the defect repaired.