Background: Nevus sebaceus (NS) of Jadassohn is a common congenital lesion associated with numerous benign and malignant tumors. However, mucoepidermoid carcinoma (MEC) has not been described in association with NS.
Methods: We describe an unusual case of MEC arising within NS.
Results: A 72-year-old man presented with an enlarging plaque on his forehead, along the hairline. Physical examination revealed a mounded, erythematous lesion that was completely excised. Histological evaluation revealed a typical MEC with areas of squamous and adenomatous differentiation with foci of typical intermediate cells.
Conclusion: The diagnosis of MEC is an important one, because it portends a poor prognosis, requiring long follow-up. This is, to our knowledge, the first report of MEC arising within NS.