Atypical meningeal hemangiopericytoma presenting with punched-out calvarial erosion

Abstract

Meningeal hemangiopericytoma (HPC) is an infrequent but distinct entity affecting the craniospinal axis. A previously healthy 48-year-old man sustained a gradually progressing motor weakness in the left lower extremity. CT showed a hyperdense mass in the right frontal lobe. On MRI, it was 29 × 30 × 36 mm in dimension, appeared isointense on T1 and hyperintense on T2, and was intensely enhanced with erosive changes in the inner table adjacent to the tumor. The patient underwent tumor resection. Reflection of the bone flap revealed a punched-out erosion in the inner table with a defect of the dura over the upper part of the tumor. Microscopic findings were consistent with grade III HPC with dural invasion. A punched-out calvarial erosion and dural defect caused by an extra-axial tumor may be a high-grade HPC that requires extensive surgical resection.

Are bone erosion and peripheral feeding vessels hallmarks of intracranial solitary fibrous tumor/hemangiopericytoma?

“…In addition, the dura mater covering the portion of the tumor with upward protrusion was eroded, which is an uncommon finding for meningiomas of the calvarial convexity. These findings were also identified in previously reported SFT/HPC cases [ 4 , 5 , 7 , 9 ].…”

“…SFT/HPCs occasionally mimic meningioma but tend to lead to a worse overall prognosis and lower survival rate due to local recurrence and distant, extracranial metastasis [ 2 , 3 ]. The presence of bone erosion, absence of hyperostosis, sunburst flow void, and intratumoral calcification, and differing values of apparent diffusion coefficient have been proposed as radiological findings differentiating between meningiomas and SFT/HPCs [4] , [5] , [6] , [7] , [8] , [9] , [10] . In contrast, meningiomas accompanying bone erosion and SFT/HPCs with calcifications have also been reported [ 11 , 12 ].…”