Primary Endodermal Sinus Tumor of the Intraspinal Cavity: A Case Report and Review of the Literature.

Endodermal sinus tumor (EST) occurs most frequently in the gonads and is relatively rare in other sites, particularly in the spinal cavity. We report a 19-year-old woman who presented with back pain and weakness of both lower extremities who was found to have an EST in the spinal canal cavity. She had severely elevated serum alpha-fetoprotein (AFP) level at presentation. Magnetic resonance imaging (MRI) revealed the mass in the spinal canal. The tumor was excised. Serum AFP returned to normal after three cycles of chemotherapy. We describe the imaging findings and the macroscopic and microscopic features of this rare tumor. EST is a relatively rare malignant germ cell tumor that usually originates in the gonads and has poor prognosis. This is a rare case of the primary EST in the spinal canal. Radiologists need to be aware of the MRI appearance of extragonadal EST.