Fetus in fetu: an institutional experience.

The objective of this article is to present an analysis of cases of fetus in fetu (FIF) diagnosed at our institute and to compare our data to that of the published literature. This is a retrospective analysis of cases of FIF diagnosed at our institute from January 2000 to December 2012. Details of clinical and investigational data pertaining to cases of FIF were retrieved from hospital records, and were analyzed and summarized. Literature was reviewed and our data were compared to that of published cases. We evaluated seven cases (4 males and 3 females) of FIF during the study period. The age of patients ranged from two days to 15 years. The most common site of occurrence in our study was the retroperitoneum, with the most common presenting feature being an abdominal mass. Radiology showed a solid-cystic mass. Pathologic findings were diagnostic of FIF. Most findings of our study matched with those reported in literature. The condition of FIF must be included in the differential diagnosis of abdominal masses, especially in children. This entity must be differentiated from the more commonly occurring teratoma, which can be done based on its unique clinical, radiologic, and pathologic characteristics. To our knowledge, this is the longest series of cases of FIF reported from a single institute.