Sacrococcygeal teratoma with spinal canal invasion

We report a case of a neonate with Altman typeⅠsacrococcygeal teratoma (SCT) with spinal canal involvement, in which ultrasonography was useful in the evaluation of the tumor progression into the spinal canal. The male fetus was diagnosed with Altman typeⅠSCT by fetal ultrasonography and magnetic resonance imaging (MRI) at 20 weeks gestation, and was born at 37 weeks gestation by Caesarean section. Abdominal MRI on postnatal day one revealed that the tumor originated from the sacral hiatus with spinal canal involvement, but the boundary between the tumor and spinal nerve was unclear. Ultrasonography of the spine clearly demonstrated that the tumor had grown into the spinal canal, it was 15 mm in length, and there was no tumor abutment of the filum terminale. The patient underwent a complete removal of the tumor with coccygectomy on postnatal day three. The postoperative course was uneventful, and the patient was discharged on the 18th day after surgery without any postoperative complications.