Erdheim-Chester disease mimicking a primary brain tumor. Case report.

Erdheim-Chester disease (ECD) is a rare systemic histiocytic disease. The authors present a case report detailing the presentation and treatment of a 26-year-old man diagnosed with seizures and a well-circumscribed temporoparietal mass that had been demonstrated on imaging studies. Both preoperative and intraoperative diagnoses were consistent with a low-grade astrocytic neoplasm. Subsequent pathological examination indicated a histiocytic proliferation positive for CD68 and factor VIII, and negative for CD1a and S100, with Touton giant cells characteristic of ECD. This case represents the first isolated occurrence of intracranial ECD and its potential to mimic glial neoplasms.