Trichoepithelioma Misdiagnosed as Basal Cell Carcinoma.

Trichoepithelioma is a benign tumor which can be easily confused with basal cell carcinoma. Since both tumors are histologically similar, it is important to distinguish them correctly as the courses for treatment are very different. Basal cell carcinoma is malignant; therefore, it requires total surgical excision, including a wide healthy margin. In contrast, trichoepithelioma requires only simple excision. A study involving a 69-year-old woman with a simple mass on the nasal tip was described in this study. On examination, a single skin-colored, round protruding mass (approximately 0.5 × 0.5 cm) was observed. Simple excision was performed and basal cell carcinoma was diagnosed at the initial biopsy. However, clinically, we considered it to be a benign tumor; therefore, we sought a histologic reconfirmation. Consequently, trichoepithelioma was diagnosed on histopathologic examination. When a small, round protruding simple mass is histologically diagnosed to be a basal cell carcinoma, it is important to suspect trichoepithelioma and seek histologic reconfirmation.