A case of fetus-in-fetu

ABSTRACT

Fetus-in-fetu is a very rare condition in which a malformed monozygotic twin lies within the body of its fellow, usually in the retroperitoneal cavity. Today it is generally accepted that the distinction between fetus-in-fetu and teratoma is largely determined by whether an axial skeleton system is present. We experienced a 6 months female infant who was admitted to our unit because of incidental abdominal mass. a plain abdominal X-ray showed that the mass contained completely formed fetal skeletal system. It was removed by surgery. By pathologic and radiologic study of mass, We confirmed as a fetus-in-fetu. We report the case with brief review of related literatures.