Primary CNS sarcoma, DICER1-mutant with rhabdomyoblastic differentiation arising within the thoracic spine:...

Primary CNS sarcoma, DICER1-mutant is almost exclusively found in the supratentorial compartment. Isolated spinal lesions are exceedingly rare.

The authors present a case of thoracic intradural extramedullary primary CNS sarcoma, DICER1-mutant. An adult male with a remote history of a left cerebellar lesion resection with unknown pathology presented with sensation changes extending caudally from the torso. He subsequently underwent laminectomy and tumor resection of the lesion. The patient experienced recurrence at 1.5 months requiring re-resection for palliative decompression.

Molecular characterization is essential for accurate diagnosis of this rare entity given its substantial overlap with histological mimics. Following resection and tissue identification of the tumor, patients should be monitored closely for local recurrence. While no standardized treatment exists, adjuvant chemoradiation therapy may improve time to progression and overall survival in an otherwise aggressive disease. https://thejns.org/doi/10.3171/CASE26660.