Adnexal tumor and a pigmented nevoid lesion in a benign cystic ovarian teratoma.

We describe a case of an unusual adnexal lesion and concurrent collections of dendritic melanocytes of the type occurring in a blue nevus in a mature cystic teratoma of the ovary. To our knowledge, there have been no previous reports of benign skin adnexal tumors in an ovarian dermoid cyst. This rarity would indicate that the cutaneous adnexal tissue in a benign teratoma is not unduly prone to undergo further more-specialized secondary tumorigenesis. The combination of the three benign lesions is therefore probably purely coincidental.