Fetiform teratoma: a rare cause of retroperitoneal mass: A case report
Fetiform teratoma is a rare highly developed mature teratoma with organoid differentiation although it is not as developed as fetus in fetus which is the only differential diagnosis of this entity. It should be distinguished from the fetus in fetu by absence of the axial skeleton. However, there is controversy in the distinction between Fetus in Fetu and fetiform teratoma and that both entities could represent two aspects of the same pathology at different stages of maturation.