Ovarian cystic teratoma: Determined phenotypic response of keratocytes and uncommon intracystic floating balls appearance on sonography and computed tomography

Ovarian cystic tumors (dermoid cysts), derived from totipotent cells, are composed mainly of a cyst lined entirely or partly by epithelium resembling keratinized epidermis with sebaceous and sweat glands. The term dermoid emphasizes the preponderance of ectodermal tissue, with the elements derived from other germ layers being inevitably present. Sonography and computed tomography (CT) can easily facilitate diagnosis of these benign cystic fatty tumors. Generally, cystic teratomas are classified into 1 of 3 categories on the basis of their configuration and components. The first type shows layering of floating debris within a tumor; the second type has nodular or palm tree-like mural protrusions; and the third type shows a fat-fluid level. We report a case of a dermoid cyst that had none of the classic sonographic features. Instead, multiple mobile fat balls were seen within the cyst, and no features of calcification, tooth, or bone were shown on sonography and CT. Also, the golden brown color of the hair in the dermoid was similar to that of the patient's scalp hair. To our knowledge, that feature, showing the determined nature of keratocytes, has not been discussed before in the literature. We present unusual sonographic and CT features of a cystic ovarian teratoma with intracystic mobile spherical masses. The spherical fat balls, some of which were admixed with hair, caused the striking feature of multiple floating masses in the cyst.