Ependymoma and intraparenchymal calcifying pseudoneoplasm of the neural axis: incidental collision or unique reactive phenomenon?
The so-called "calcifying pseudoneoplasm of the neural axis" is a rare tumefactive lesion presumed to be reactive in nature. To our knowledge, association with a true neoplasm has not been previously reported. We recently encountered the case of a 67-year-old woman who underwent resection of an incidentally discovered cerebellar cystic mass with a distinct, calcified component. Histology demonstrated a partially ossified, lobulated, chondrocalcific lesion surrounded by chronic inflammation, spindle to epithelioid cells, and occasional multinucleated giant cells-all features of calcifying pseudoneoplasm of the neural axis. A low-grade ependymoma associated with marked piloid gliosis was found contiguous to the lesion. The unique combination of an ependymoma with marked reactive gliosis and a calcifying pseudoneoplasm supports the reactive nature of the latter.
Rodriguez
Fausto J
FJ
Department of Laboratory Medicine and Pathology, Mayo Clinic, 200 First Street, SW, Rochester, MN 55905, USA. rodriguez.fausto@mayo.edu
Scheithauer
Bernd W
BW
Fourney
Daryl R
DR
Robinson
Christopher A
CA
D000368:Aged; D001927:Brain Diseases / Q000150:complications* / Q000473:pathology; D002114:Calcinosis / Q000150:complications* / Q000473:pathology; D002528:Cerebellar Neoplasms / Q000150:complications* / Q000473:pathology; D004806:Ependymoma / Q000150:complications* / Q000473:pathology; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D014057:Tomography, X-Ray Computed