Teratomas are neoplasms that are composed of a mixture of tissues, more than one of which exhibits neoplastic proliferation.They are congenitally acquired and are usually found in the ovary. Rare examples, either arising from the oral cavity or protruding into the oral cavity from the base of the skull, have been described in children. The finding of various organlike structures (ie, teeth, tissue, hair, and skin) in these tumors and their common location in the ovary may give the
misleading impression that they are fetal malformations rather than neoplastic growths of developing tissue; the latter is the currently accepted understanding and clearly provides a more convincing explanation for oral teratomas than does the former. Teratomas that arise from the base of the skull often extend into the cranial cavity as well as the oral cavity, and
newborn infants with such lesions rarely survive. No single histologic picture is characteristic although the usual appearance of disorganized neoplastic tissues of various types readily identifies the lesion to the pathologist.
Some teratomas of the ovary are primarily cystic; these are often referred to as dermoid cysts because they may include epidermal tissue and even hair follicles. Dermoid cysts
of the oral cavity are most commonly encountered in the floor of the mouth although they may arise in other soft-tissue locations (Figures 7-18 and 7-19). These cysts also feature epidermal tissues and (even) hair follicles, sweat and sebaceous glands in the cyst wall, and keratin and sebum in the cyst cavity. Cysts that harbor tissues from all three germ layers are more correctly referred to as teratoid cysts.
Some teratomas of the ovary are primarily cystic; these are often referred to as dermoid cysts because they may include epidermal tissue and even hair follicles. Dermoid cysts
of the oral cavity are most commonly encountered in the floor of the mouth although they may arise in other soft-tissue locations (Figures 7-18 and 7-19). These cysts also feature epidermal tissues and (even) hair follicles, sweat and sebaceous glands in the cyst wall, and keratin and sebum in the cyst cavity. Cysts that harbor tissues from all three germ layers are more correctly referred to as teratoid cysts.