Prenatal Diagnosis of Oral Teratoma by Ultrasound

A pregnant woman had a normal second-trimester anatomic survey at 22 weeks gestation. She was revealed to have a fetal oral mass with polyhydramnios and invisible stomach bubble by ultrasound at 28 weeks. A 50 mm × 36 mm × 42 mm, solid mass was found in the fetal mouth, filling the entire oral cavity. Fetal magnetic resonance imaging showed a homogeneous solid mass in the oral cavity compressing the hypopharynx. At 33 weeks, preterm labor occurred because of the continuation of increased amniotic fluid volume, and a female infant was vaginally delivered. The infant died shortly after tracheal intubation attempt failed. Autopsy confirmed the prenatal sonographic finding. The final pathologic diagnosis was oral immature teratoma. Our study indicates that although oral teratomas are rare, they are readily apparent at prenatal sonographic examinations. Respiratory compromise is the frequent complication of oral teratomas, which is associated with high perinatal mortality.

Mature Triphyllic Cystic Teratoma of the Posterior Mediastinum in a Fetus: A Case Report and Literature Review

A teratoma is a neoplasm composed of cell populations or tissues that are reminiscent, in their appearance, of normal elements derived from at least two embryonic layers. Fetal mature teratomas are normally benign, cystic, and typically occur along the midline, while they are rare in the posterior mediastinum. Teratomas are frequently solitary; however, they may sometimes be associated with other congenital anomalies and/or with chromosomal abnormalities. Clinically, they are often asymptomatic but can occasionally cause compression symptoms. Prenatal diagnoses are uncommon and made with ultrasonography; differential diagnosis with other congenital conditions is mandatory. We report the case of a 21 weeks of gestational age old fetus with a mature triphyllic fetal cystic teratoma, grade 0, located in the right posterior mediastinum. The tumor presented as a 3 cm wide cystic mass that caused a contralateral shift of the surrounding structures. Histological examination later revealed the presence of derivatives of the three germ layers, such as hyaline cartilage, smooth muscle, nervous tissue, and a respiratory-type epithelium.

Prenatal diagnosis and outcomes of fetal teratomas

PURPOSE

Our aim was to evaluate the diagnostic performance of ultrasonography (US) in the prenatal identification of teratomas and the perinatal outcome of the fetuses with those teratomas.

METHODS

In this retrospective case series study, we searched the archives using the keywords "fetal mass" or "fetal tumor" or "fetal teratoma" and "sacrococcygeal teratoma," diagnosed between 2009 and 2014, within the US database of our center.

RESULTS

One hundred seven fetuses were prenatally diagnosed as having a cystic or solid mass, tumor, or teratoma. Nineteen of those cases were diagnosed prenatally as having fetal teratoma, but that diagnosis could not be verified in three cases. In one fetus, the prenatal diagnosis could not be confirmed. The sensitivity of US in identifying fetal teratoma was 100% and the false-positive rate, 3.3%. Six pregnancies complicated by a fetal teratoma were terminated. A normal karyotype was identified in all fetuses that underwent karyotyping. Among the nine women who continued their pregnancy, polyhydramnios was identified in four fetuses; although high-output heart failure was also identified in two of those fetuses during prenatal follow-up, none developed hydrops. On delivery, nine infants were born alive, but three (33.3%) of them died within the early neonatal period.

CONCLUSIONS

US has very high sensitivity and low false-positive rates in identifying fetal teratoma prenatally. The risk of chromosomal abnormalities is very low in fetuses with teratoma, and their prognosis depends on the location and size of the tumor and any associated perinatal complications.