![]() Tumors containing representatives of one layer only ( dermoid cysts, osteomata, chondromata, etc.).Tumors containing representatives of two germinal cell layers only.A tumor consisting of all three germinal layers.A portion of a second fetus in the orbit.A complete fetus implanted in the orbit (orbitopagus parasiticus).ClassificationĬlassification of Orbital Teratomas by Mizuo and Duke-Elder Most cases reported in the literature are cytologically benign, however in some cases, tumors may grow rapidly, and severe complications may ensue. A review of the literature showed that females are affected more than males in an approximately 2:1 ratio, with a propensity of the tumor to occur more frequently in the left than in the right orbit. Teratomas account for 6.6% of childhood tumors, most commonly occurring in the testes, ovaries, and retroperitoneum the orbit is a very rare site. Orbital teratomas reported so far have been unilateral, and tumors cited as bilateral seem to have been limbal dermoids. Teratomas, the most common of orbital germ cell tumors, probably arise from pluripotential embryonic stem cells that are carried to the orbit by blood circulation and escape regulatory influences, or from primordial germ cells that aim toward the pineal gland, even though other theories have also been proposed. Seven years later, Lawson reported an orbital teratoma that extended into the intracranial cavity, and in 1924 Prym briefly described an intracranial teratoma extending into the orbit. Holmes first reported an orbital tumor compatible with a teratoma in 1863, but due to the primitive histopathological methods available at that time, Broer and Weigert are credited with describing the first unquestionable orbital teratoma in 1876. ![]() ![]() The origin of teratoma has been derived from Greek word “Teratos” and “Oma”.The literal meaning of which accounts to teratos meaning unusual occurrence or phenomenon, monster and oma meaning complete set of, or a condition. įig.1: Frontal view of a huge orbital teratoma with compressed eyeball in a two day old female neonate. The orbit is a rare, but typical, location in which primary extragonadal germ cell tumors arise.
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