WOFAPS 2025 8th World Congress of Pediatric Surgery

Ali Samady Khanghah ¹, Anahita Abdolzadeh ¹, Mahdi Parvizi-Mashhadi ², Khashayar Atqiaee ²

¹ Ardabil University of Medical Sciences
² Mashhad University of Medical Sciences

Purpose: The fetus in fetu (FIF) expression refers to an infrequent congenital phenomenon characterised by a second fetus growing into the body of the healthy twin. This study aimed to review the few cases located in the thoracic cavity.

Method: We searched the central medical databases of PubMed/Medline, Web of Science, Scopus, ScienceDirect, and Google Scholar, as well as the references of the articles, to collect nine cases of FIF in pediatric patients' thoraxes. The inclusion criteria were full-text available literature and those published for individuals under 19 years old. Intra-abdominal or extra-thoracic cases and the presence of malignant components made our exclusion criteria.

Results: There was only one case diagnosed during adolescence. The remaining children were under 10 months old at the time of intervention. There were four males, three females, and two cases with non-declared sex. The entire mass was found in the mediastinum, but one was located intrapulmonary. All cases had undergone thoracotomy. The minimum survival time mentioned in the literature was five months. The adipose tissue was the most frequently identified tissue among the resected masses, with eight cases reported, followed by the vertebral column and bony tissues, with six and five cases mentioned, respectively.

Conclusion: An infant suffering from respiratory distress or even recurrent infections, particularly with a mass revealed in its chest radiography, should raise a suspicion of FIF. This doubt will be strengthened if an axial skeleton or bony densities are found.