Lumbar Psammomatous Spinal Meningioma with Osseous Metaplasia: A Rare Location and Diagnostic Challenge

Psammomatous meningiomas are rare, low-grade spinal tumors characterized by the presence of psammoma bodies, which often overlap with metaplastic meningiomas that exhibit osseous components. This overlap presents a diagnostic challenge due to the presence of both shared and distinct pathological features. This case report describes the case of a 76-year-old woman who presented with chronic left buttock pain and progressive difficulty in ambulation. Imaging studies, including lumbar radiography, magnetic resonance imaging, and computed tomography, revealed a well-defined calcified intradural extramedullary mass at the L1 level of the spinal canal. Under general anesthesia with intraoperative neuromonitoring, T12 subtotal laminectomy and L1 total laminectomy were performed, enabling en bloc resection of the tumor. Histopathological analysis confirmed psammomatous meningioma with osseous metaplasia, characterized by psammoma bodies surrounded by meningothelial cells and metaplastic bone formation. This case highlights the importance of differentiating overlapping pathological entities to achieve accurate diagnosis and optimal surgical management.