Surgical resection and full-thickness skin grafting for sebaceoma extending into the external auditory canal: a case report.

Sebaceoma is a rare benign cutaneous adnexal neoplasm with sebaceous differentiation that typically occurs in the head and neck region of elderly individuals. Sebaceoma extending into the external auditory canal is extremely uncommon. We report the case of an 85-year-old woman who presented with an enlarging mass involving the left tragus and extending into the external auditory canal. Histopathological examination demonstrated dermal nests of basaloid cells with sebaceous differentiation, and immunohistochemical analysis showed focal positivity for epithelial membrane antigen and Ber-EP4, leading to a diagnosis of sebaceoma. Complete excision and reconstruction with a full-thickness skin graft were performed. The postoperative course was uneventful, with complete graft survival, preservation of external auditory canal patency, and no evidence of recurrence at 6 months postoperatively. This case highlights the rarity of sebaceoma involving the external auditory canal and the importance of considering possible associations with Muir-Torre syndrome.