Giant epidermoid cyst of the posterior neck.

A 49-year-old man was presented for evaluation of a painless mass on his right posterior neck. The mass had gradually enlarged for a 25-year period without inflammation or rupture. On physical examination, a round, nontender, soft-tissue mass, 8 cm in diameter, was noted on the right posterior neck. The neck is a common site of epidermoid cysts, but a mass more than 5 cm in diameter is rare. A contrast-enhanced neck computed tomographic (CT) scan revealed a 7.6 × 6.5 × 5.7 cm unilocular hypodense mass adjacent to the posterior neck muscles.The mass was completely excised under general anesthesia. A histopathologic examination of the excised specimen resulted in a diagnosis of an epidermoid cyst. The patient was discharged from the hospital on the third postoperative day. There were no recurrences in a 2-year follow-up period.