A Rare Presentation of Basal Cell Carcinoma Arising within Trichoepithelioma: A Diagnostic Challenge.

Differentiating between trichoepithelioma and basal cell carcinoma (BCC) is sometimes diagnostically challenging. We present a case of a 61-year-old male with a BCC arising within a trichoepithelioma, which is rarely reported in the literature. Clinical and histological diagnosis of trichoepithelioma is sometimes complicated by its many similarities to BCC. Therefore, immunohistochemical analysis and adequate tissue sampling are essential in suspicious lesions. In addition, as represented by our patient's presentation, it is important for clinicians to remember that the presence of a concurrent malignant neoplasm may be masked by the benign nature of a trichoepithelioma and that a superficial shave biopsy may not be sufficient for accurately diagnosing such suspicious lesions.