Object: Central nervous system primary germ cell tumors are typically pineal or suprasellar. Primary germ cell tumors of the spinal axis are very rare, with only a few case reports of germinomas and teratomas described in the literature.
Methods: We present the unique case of a 25-year-old woman with an intradural, extramedullary primary yolk sac tumor (YST) at and below the level of the conus medullaris. The patient was treated with a subtotal resection and within a month had rapid regrowth of her YST. She was subsequently treated with four cycles of chemotherapy (intravenous cisplatin and etoposide), 40-Gy fractionated focal external beam radiation to the spine, and consolidation with four additional cycles of chemotherapy (intravenous carboplatin, vinblastine, etoposide, and bleomycin). Despite an initial reduction in tumor size and clinical improvement in her neurologic exam, she re-presented a year after surgery with gross enlargement of her spinal tumor and CSF dissemination with metastasis to her brain. Despite further chemotherapy and radiotherapy, the patient died from her disseminated YST.
Conclusions: This case demonstrates that primary YSTs may occur in the spine, and like their intracranial counterparts, are associated with poor prognosis and dissemination through the neuroaxis. When feasible (no evidence of CSF dissemination, metastasis, or multifocal disease), optimal treatment includes as extensive resection of tumor as possible followed by adjuvant chemotherapy and radiation. The authors review the available literature on the treatment of intracranial malignant germ cell tumors, extrapolated to apply to the much rarer spinal lesions.