Xanthogranuloma of the Erdheim-Chester type within the sellar region: case report.

Manifestations of Erdheim-Chester disease in the central nervous system are very rare. Cases with localization in the retroorbital space, hypothalamic area and posterior pituitary as well as intracerebral lesions are known. In our neurosurgical unit, a 51-year-old male patient with a history of hypophyseal insufficiency and visual deficits underwent surgery for a pituitary lesion. Histological and immunohistochemical examination revealed a xanthogranulomatous lesion composed of very large CD68-positive foam cells with small nuclei and some Touton-like giant cells, histiocytes, as well as loci with small lymphocytes and isolated eosinophilic granuolcytes, embedded in fibrotic tissue. Based on these findings, the histological diagnosis was a xanthogranuloma of the Erdheim-Chester type.