Calcifying pseudoneoplasms of the neuraxis (CAPNON). A case report

Area of Science:

• Neuropathology
• Neuroimaging
• Genetics

Background:

• Calcifying pseudoneoplasms of the neuraxis (CAPNON) are uncommon, benign lesions of the central nervous system.
• These lesions are frequently misdiagnosed due to their varied presentation and slow growth.
• Accurate diagnosis is crucial to avoid misclassification as neoplastic or infectious processes.

Observation:

• A 56-year-old woman presented with a six-year history of recurrent headaches.
• MRI revealed a 2.3 cm right frontal lobe mass with dense calcification, avid enhancement, and surrounding edema.
• Initial diagnosis was oligodendroglioma, but histopathology confirmed CAPNON.

Findings:

• Histopathological examination of the resected lesion was essential for definitive CAPNON diagnosis.
• Genetic analysis identified a nonsense mutation in the CUL4B gene.
• The observed condition was interpreted as a reactive process rather than a true neoplasm.

Implications:

• Increased awareness of CAPNON among clinicians is necessary to improve diagnostic accuracy.
• Histopathological confirmation is key to differentiating CAPNON from other intracranial pathologies.
• Avoiding unnecessary diagnostic workups and potentially harmful treatments for misdiagnosed CAPNON is critical.