Summary

Immature teratoma of the stomach in the neonate is extremely rare.1^,2 This report outlines a case of giant immature teratoma of the stomach, which was detected by prenatal ultrasonography in the third trimester as an echogenic mass contiguous with the stomach bubble. It increased from 4.5 cm in diameter to 7 cm between 34 and 37 weeks gestation. The baby was delivered by elective caesarean section at 37 weeks gestation. Neonatal imaging highlighted a differential diagnosis of nephroblastoma, neuroblastoma, pancreatoblastoma and teratoma. The infant underwent surgical excision of the abdominal mass on the 10th day of life. Histology revealed grade III immature gastric teratoma arising from the posterior wall of stomach, outlining the unknown implications of such a designation in an extraovarian site. The infant made a good postoperative recovery and is currently well 9 months later, without adjuvant therapy, and with no evidence of recurrent disease.