IMG-119. “The Spine’s Silent Aggressor: Imaging and Molecular Profile of MYCN -Amplified Ependymoma”

BACKGROUND MYCN-amplified spinal ependymoma is a recently classified, rare, and aggressive subtype of spinal cord tumor, first defined by the 2021 WHO CNS5 classification. It predominantly affects adults in their 30s, with a slight female predominance; fewer than 50 cases have been reported worldwide. PURPOSE To characterize the molecular, imaging, and clinical features of MYCN-amplified spinal ependymomas and highlight their distinctiveness to aid in early diagnosis and therapeutic planning. METHODS We retrospectively reviewed institutional cases of MYCN-amplified spinal ependymomas and performed a literature-based analysis. Data on imaging, histopathology, molecular profiles, and clinical outcomes were examined to identify distinguishing diagnostic and prognostic features. RESULTS These tumors are typically present as intradural extramedullary masses, often in the thoracic spine, with intense contrast enhancement and prominent peritumoral edema. A lack of a clear cleavage plane with the spinal cord, early leptomeningeal, and intracranial dissemination are hallmark features. Rare reports of systemic metastases (e.g., to the humerus and paraspinal muscle) exist. Histologically, they are high-grade (WHO grade III) anaplastic ependymomas with a distinct DNA methylation profile. MYCN amplification—commonly seen in medulloblastomas and glioblastomas—drives tumor aggressiveness. Clinically, these tumors are refractory to standard treatments, with high rates of recurrence or progression within 1–2 years post-treatment. The median overall survival is approximately seven years, significantly poorer than conventional spinal ependymomas. CONCLUSION MYCN-amplified spinal ependymomas represent a rare but highly aggressive tumor subtype with unique imaging, histological, and molecular features. Early recognition is critical given rapid progression and poor prognosis. Investigational therapies targeting MYCN—such as HDAC, PARP, Aurora A-kinase, and BET inhibitors—hold promise for improved outcomes.