We present a case of nasopharyngeal immature teratoma, also called epignathus teratoma.

Imaging demonstrated the following findings:

• Image 1, Video 1,2: Our ultrasound examination performed at 25 and 27 weeks revealed an unusual oropharyngeal mass with unusual echoic spots that did not look like facial bones.
• Image 2, Video 3-5: Follow up ultrasound at 31 weeks of pregnancy demonstrated rapid growth of the mass that was now protruding out of the oral cavity, pushing the tongue down and out. It was a solid mass with some internal echos, most likely calcifications or ossifications.
• Images 3-8: MRI examination showed the extent of the mass, filling both the oropharynx and nasopharynx, and protruding through the base of the skull next to the pituitary fossa, likely extending through foramens (ovale and round foramen) around the sphenoid bone.

The fetus died in utero at 32 weeks of pregnancy. Placental examination revealed a massive retroplacental hematoma, which was likely the cause of intrauterine demise.

Autopsy examination revealed a tumor arising from the nasopharynx/cavum, protruding through the oropharynx and oral cavity, and also invading the central base of the skull around the pituitary fossa (Images 9-12). The fetus had normal morphology with mild intrauterine growth restriction (-2 weeks gestation). Histology of the tumor showed a mix of epithelial, bone, chondroid and immature nervous tissues (Image 13).

Our final diagnosis was nasopharyngeal immature teratoma, also called epignathus teratoma.

References
[1] Sleurs E, de Catte L. "Case of the Week #37." TheFetus.net. https://thefetus.net/content/case-of-the-week-37, publish date 10/2000.