Calcifying pseudoneoplasm of the neuraxis (CAPNON)

New Insights into CAPNON: A 20-Year Radiologic-Pathologic Study of 37 Cases.:

Related Articles

New Insights into CAPNON: A 20-Year Radiologic-Pathologic Study of 37 Cases.

Histopathology. 2020 Jan 19;:

Authors: Ho ML, Eschbacher KL, Paolini MA, Raghunathan A

Abstract

AIMS: Calcifying pseudoneoplasm of the neuraxis (CAPNON) is a rare entity that can occur anywhere within the central nervous system. At histology, CAPNON has been characterized as a benign, calcified, fibro-osseous lesion with characteristic chondromyxoid fibrillary matrix with dense calcification and varying degrees of spindle, epithelioid, fibrous, meningothelial, and giant cells. The underlying etiology for CAPNON is controversial and incompletely understood. The objective of our study was to perform a comprehensive radiologic and histologic review to further characterize this entity.

METHODS AND RESULTS: In this paper, we review our institutional 20-year experience including 37 cases of CAPNON with detailed pathologic analysis, evaluation of concurrent lesions, correlation with radiologic imaging, and critical review of the literature. The classic histologic finding of chondromyxoid matrix was present in one third of cases. Underlying or dual pathologies were a frequent feature and include diverse underlying conditions. Radiologically, dense calcification and dural attachment were the most common features. Enhancement was often low, but was more prominent in the setting of inflammatory changes, aggressive growth, and dual pathology.

CONCLUSION: Our results suggest that CAPNON represents a spectrum of reactive processes that can arise in association with diverse underlying pathologies including inflammatory, degenerative, vascular, and neoplastic lesions.

PMID: 31955449 [PubMed - as supplied by publisher]