Recurrent myxopapillary ependymoma: A diagnostic challenge.

INTRODUCTION: Myxopapillary ependymomas are a subset of spinal ependymomas that arise almost exclusively in the conus medullaris and filum terminale, and most commonly affect young adults. However, multifocality has been described, originating in the cervicothoracic spinal cord, the lateral ventricle, the fourth ventricle, and the brain. Spinal myxopapillary ependymomas are associated with a favourable prognosis in children and adults, with 10-year overall survival rates > 90%. Many patients, however, live with persistent disease and require repeated operations and adjuvant therapy, because myxopapillary ependymomas often resist complete removal owing to locally advanced growth and/or cerebrospinal fluid-borne seeding of the thecal sac or more rostral neuraxis.

CASE REPORT: We present a case of a 27-year-old woman who underwent gross-total resection and adjuvant radiotherapy for an L2-L3 spinal tumour, which was diagnosed histologically as ependymoma, but developed a recurrent tumour of myxopapillary ependymoma after a long-term symptom-free period. The recurrent tumour is larger, multifocal, heterogeneously enhancing and extending from the lumbar into the sacrum, resulting in local effects on the bones. Previously, the diagnosis of ependymoma was based solely on histomorphology, with no molecular confirmation of DNA methylation profiling.

DISCUSSION: This case highlights the importance of diagnostic accuracy when molecular testing is limited, emphasising the crucial role of clinical and histopathological correlation. Hence, a histo-molecular classification is vital for risk stratification and tailored surveillance.