Calcifying Pseudoneoplasm of the Neuraxis: A Case Illustrating Natural History over 17 Years of Radiologic Surveillance.

Abstract

Calcifying pseudoneoplasm of the neuraxis (CAPNON) is a rare central nervous system lesion that can occur in both the brain and the spine. Although this entity is poorly understood, radiologic and histological features have been identified. We report a unique case of a 31-year-old patient who was managed with antiepileptic medication for 17 years before requiring neurosurgical intervention for tumor progression. T2-weighted magnetic resonance imaging revealed hyperintensity within the tumor with extensive associated vasogenic edema, which is not normally associated with CAPNON. Resection was successful with no complications. The present case illustrates the long-term natural history of CAPNON before resection and highlights the variations in radiologic appearance that may be associated with this poorly understood entity.