Late dissemination of fourth ventricle ependymoma: a case report.

Dissemination of benign ependymoma is relatively rare, especially when a local tumor is under control. The majority of the failures take place within a few years after surgery. However, we experienced a case in which multiple spinal cord dissemination was found 13 years after resection of the fourth ventricle ependymoma without a local failure. A 38-year-old man had undergone a subtotal resection of the fourth ventricle ependymoma and radiation therapy to the posterior fossa when he was 25 years old. Follow-up MR imaging repeated once every one or two years detected no recurrence until he began to complain of lumbago and numbness of the right foot 13 years after the surgery. MR imaging revealed multiple nodules along the whole spinal cord. Examination of the cerebrospinal fluid detected tumor cells with ependymal cell features. He underwent radiation therapy to the whole spine, and remained stable at 18 months after the therapy. This case alerts us to the necessity for long-term radiological follow-up including the spinal cord even in benign ependymomas, although it is still not certain for how long and how often we should do it.