A Case Report and Literature Review of Fetus in Fetu – A Rare Aberration of Embryogenesis in a 22-month old Infant


  • Ma. Femie Japitana West Visayas State University Medical Center
  • Josefa Hilado West Visayas State University Medical Center
  • Lysa Lynn Libanan West Visayas State University Medical Center


fetus-in-fetu, teratoma, intra-abdominal mass, fetoid


Fetus in fetu (FIF) is an uncommon pathology resulting from an abnormal embryogenesis occurring in a diamnionic, monochorionic twinning during pregnancy. It is so rare that there is only one underdocumented case reported in the Philippines. We are faced with a curious case of a 22-month old male child who presented with a gradually enlarging abdomen, diagnosed as FIF as confirmed by radiologic studies. After undergoing the necessary laboratory and radiologic work-ups, the patient was stabilized and eventually cleared for surgery. He underwent exploratory laparotomy with excision of FIF, from which a fetoid structure was recovered. Thorough gross and further radiologic evaluation of the recovered fetoid structure reveals findings that fulfilled the diagnostic criteria of a FIF.


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Author Biographies

Ma. Femie Japitana, West Visayas State University Medical Center

Medical Officer III/Resident Pathologist Level II

Josefa Hilado, West Visayas State University Medical Center

Medical Officer IV

Resident Pathologist Level III

Lysa Lynn Libanan, West Visayas State University Medical Center

Training officer-Anatomic Pathology


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How to Cite

Japitana, M. F., Hilado, J., & Libanan, L. L. (2016). A Case Report and Literature Review of Fetus in Fetu – A Rare Aberration of Embryogenesis in a 22-month old Infant. PJP, 2(1), 30. Retrieved from https://philippinejournalofpathology.org/index.php/PJP/article/view/44



Case Reports