Fetus-in-fetu arising from the palate treated with ex-utero intrapartum treatment

Riku Suzui1, Hiroshi Sato2, Makiko Ikeda2

  • 1Gynecology and Obstetrics, Hyogo Prefectural Amagasaki General Medical Center, Amagasaki, Japan r_suzui@kuhp.kyoto-u.ac.jp.

BMJ Case Reports
|August 13, 2026
PubMed

Epignathus, a teratoma arising from the palate or pharynx, is extremely rare and palatal fetus-in-fetu represents an even rarer anomaly. We report a prenatally diagnosed palatal fetus-in-fetu successfully managed with ex utero intrapartum treatment (EXIT). A 4 cm oral mass detected at 23 weeks caused polyhydramnios and gastric shrinkage, suggesting impaired swallowing and potential airway obstruction. Multidisciplinary evaluation determined the need for EXIT to secure the airway under placental circulation. At 34+5 weeks of gestation, caesarean delivery with EXIT was performed; a 14 cm tumour was delivered and tracheostomy followed by staged resection was undertaken. Histopathology revealed multiple differentiated tissues-including nerve, gastrointestinal tract, adrenal gland, skin, bone and teeth-meeting Spencer's criteria for fetus-in-fetu. The infant recovered well and was discharged 96 days postnatally. EXIT proved invaluable for airway management in high-risk epignathus, and fetus-in-fetu differs from teratoma by its lower malignant potential, emphasising individualised prenatal planning and team collaboration.

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