MYCN-amplified spinal ependymomas: a rare aggressive subtype. Illustrative cases.

BACKGROUND

Spinal ependymomas are typically slow-growing tumors with a favorable prognosis. Recently, a new aggressive subtype has emerged with its own distinct histopathological and molecular features characterized by MYCN amplification. However, this subtype of spinal ependymoma is rare, and studies on its imaging characteristics are limited. In this case series, the authors present the imaging findings of three patients with MYCN-amplified spinal ependymoma from their institution.

OBSERVATIONS

Unlike typical spinal ependymomas, the MYCN-amplified spinal ependymomas were intradural extramedullary in location in the thoracic and lumbar spine. Imaging revealed T1 isointensity and T2 hyperintensity with avid enhancement and peritumoral edema. The tumor masses were adherent to the spinal cord with filling of the canal and resultant cord compression. There were focal areas without a clear tissue plane between the mass and the cord, which was concerning for cord infiltration. Thus, complete resection was difficult to achieve, and all patients demonstrated residual tumor in the resection bed. Their clinical course was also characterized by early central nervous system (CNS) dissemination, including one case with intracranial involvement.

LESSONS

This case series highlights three instances of MYCN-amplified spinal ependymoma, a rare and aggressive subtype with distinctive imaging features, including an intradural extramedullary location and CNS dissemination at recurrence. https://thejns.org/doi/10.3171/CASE24696.