✓Fetus-in-fetu is a very rare condition in which one fetus is contained within another. About 100 cases have been reported, and in most of these the fetus was located in the retroperitoneum. The authors describe an extremely rare case of an intracranial fetus-in-fetu in an extraaxial location. This is the eighth intracranial fetus-in-fetu to be reported, the first intracranial extraaxial case, and involves the oldest documented patient with this condition.
Histopathological analysis of the mass revealed a degenerated amnionic membranelike tissue, well-differentiated extremities (including fingerlike structures), skin, matured lungs, well-formed intestines, cerebellar and cerebral tissue, and a notochord with ganglion cells. DNA analysis using short tandem repeat polymorphisms confirmed that the fetus-in-fetu mass and the host infant had heterozygous alleles and were of identical sex and genotype.
Abbreviations used in this paper: CT = computed tomography; MR = magnetic resonance; STR = short tandem repeat.
Address correspondence to: Seung-Ki Kim, M.D., Ph.D., Division of Pediatric Neurosurgery, Seoul National University Children's Hospital, 103 Daehangno, Jongno-gu, Seoul 110-799, Republic of Korea. email:
BärWBrinkmannBBudowleBCarracedoAGillPLincolnP: DNA recommendations. Further report of the DNA Commission of the ISFH regarding the use of short tandem repeat systems International Society for Forensic Haemogenetics. Int J Legal Med110:175–1761997