STILL BORN WITH BONY MASS IN ABDOMEN

Fetus in fetu {FIF} is a rare developmental abnormality {incidence of 1 in 5,00,000 live births} in which a mass of tissue resembling a fetus forms inside the body. {1} The FIF complex is characteristically composed of a fibrous membrane {equivalent to the chorioamniotic complex} that contains some fluids {equivalent to the amniotic fluid} and a fetus suspended by a cord or pedicle. {2} There are two main theories about the development of fetus in fetu. {3} Teratoma Theory proposes fetus in fetu as a highly differentiated form of mature teratoma and a Parasitic Twin Theory proposes Fetus in fetu as a parasitic twin fetus growing within its host twin. The parasitic twin is usually anencephalic and lacks some internal organs, and as such is almost always unable to survive on its own. Most FIF are located retroperitoneally, while other rare reported sites include the cerebral ventricles, liver, pelvis, scrotum, and mediastinum. {4} FIF is a benign condition, but the mass may compress the surrounding organs and tissue. Therefore symptoms of FIF are primarily due to its mass effect. Although the prognosis for FIF is more favorable than for cystic teratoma, the presence of immature elements nevertheless indicates the need for close clinical, radiological and serological {AFP} follow-up.

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References :

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