Calcifying Pseudotumor of the Neural Axis —Case Report—

Abstract

A 22-year-old female presented with a calcifying pseudotumor of the neural axis manifesting as generalized convulsive seizure twice within 1 year. Computed tomography revealed a small, calcified mass lesion located in the right parietal lobe adjacent to the skull. The tumor was composed of an ex tensively calcified mass with accompanying peripheral epithelioid cells and focal mature bone struc ture, consistent with the diagnosis of a calcifying pseudotumor of the neural axis. Following complete excision of the tumor, the patient has been free from seizures for 8 years.

Calcifying Pseudoneoplasms of the Neuraxis: CT, MR Imaging, and Histologic Features

“…[2][3][4][5][6][7][8]10 Most reported lesions have been extra-axial, but several intra-axial cases have also been reported. 1,2 The lesions seem to be slow growing with presenting symptoms related to local compression or irritation of adjacent tissues.…”

“…Since the original pathologic description by Rhodes and Davis, 1 there have been approximately 32 reported cases. [2][3][4][5][6][7][8][9] We found 32 additional cases reported in the literature: 11 spine CAPNON and 21 intracranial CAPNON. Of the intracranial lesions, most were extra-axial and were located at the skull base.…”

Calcifying Pseudoneoplasms of the Skull Base Presenting with Cranial Neuropathies: Case Report and Literature Review

“…Calcified, fibro-osseous lesions known as calcifying pseudoneoplasms of the neuraxis, cerebral calculi, or brain stones are extremely rare and are usually seen at the cranial base, commonly adjacent to the dura mater or the arachnoid 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29. However, they can occur anywhere within the neuraxis 2,3,5.…”

“…The patients with intracranial type most commonly presented with seizure (31.6%) followed by headache (13.2%) and cerebellar sign (5.3%) 1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23. Three patients (8.1%) were found incidentally, and seven cases (18.9%) were autopsy findings.…”

“…Microscopically, the differential diagnosis of calcifying pseudoneoplasms includes a variety of reactive lesions such as granulomatous disease, herniated disk material, and even neoplastic lesions like chondroid chordoma, chondroma, chondrosarcoma, metaplastic meningioma, or calcified primary parenchymal central nervous system tumors 6. In most cases, immunohistochemistry findings for vimentin were positive, with negative staining for glial fibrillary acidic protein and S-100 3,5,6,17,19. Vimentin immunoreactivity was noted in peripheral palisading cells, but the intensity varied from case to case 5,17.…”