An Extremely Rare Case of Back and Hip Pain due to the Metastasis of Late Recurrent Myxopapillary Ependymoma to the Inguinal Lymph Node

Abstract

Myxopapillary ependymomas (ME) are rare and slowly growing gliomas usually with spinal cord localization originating from the ectopic ependymal residues. They are commonly located in the conus medullaris, cauda equina and filum terminale. ME is known to be more aggressive in childhood, but has a good prognosis in adults with a very low metastasis risk.(1,2) If successfully excised, ME are usually cured completely. However, in adults, ME at the sacrococcygeal region metastasizing to organs outside central nervous system has rarely been reported so far.(3-5) Herein, we report an extremely rare case of an inguinal lymph node metastasis developed 19 years after removal of primary ME at the sacrococcygeal region, which presented with unusually severe back and hip pain. Because the metastasis of ME to the lymph node after such a long time is rare, our case may contribute to improving the differential diagnosis of extremely rare metastatic ME cases and identifying their unexpected role in the pain of unknown origin.