Primary meningeal inflammatory pseudotumor

Abstract

Inflammatory pseudotumors (IPs) encompass a wide spectrum of pathological entities of varying nomenclatures such as plasma cell granuloma, xanthomatous pseudotumor, and hypertrophic pachymeningitis. Majority of them are of uncertain etiology. Such tumor-mimicking lesions have been described in the lungs, liver, peritoneum, and retroperitoneal spaces. Primary convexity meningeal occurrence without intracerebral extension or extracranial presence is uncommon. We present one such rare case of a 50-year-old woman having a convexity primary meningeal IP with a 4-year follow-up post-excision. Radiology of IP may be nonspecific and pathological diagnosis is necessary in most cases to rule out meningeal neoplasms or infections, autoimmune/vasculitic, and other unusual mimics. Although surgical excision is warranted, complete resection may not be necessary if the frozen report is diagnostic. The differential diagnosis and treatment options are discussed further and a flowchart is provided depicting the meningeal tumor mimics.