Xanthogranuloma of the Sellar Region

Fig. 23.1

(a) Sagittal T1-weighted post-gadolinium image. (b) Coronal T1-weighted pre-gadolinium image. (c) Coronal T1-weighted post-gadolinium image. There is a lobulated cystic lesion in the sella containing T1 hyperintense material. The pituitary stalk is displaced anteriorly

23.3 Histopathology

Extensive inflammation with no readily identifiable epithelium is seen in the majority of cases [1, 8].
Frequent histopathological findings include cholesterol clefts, macrophages, chronic inflammatory infiltrates, necrotic debris, foamy histiocytes, and hemosiderin deposits [4].
Because these lesions may not have an epithelial lining, immunohistochemistry for cytokeratins is negative [8].
Although they have been reported to comprise a distinct entity, it remains unknown whether they are derived from RCCs, craniopharyngiomas, and/or other lesions.
Features of xanthogranuloma have been reported to be more consistent with RCCs than with craniopharyngiomas; they have demonstrated a high association with squamous metaplasia of these lesions [8], as seen in Fig. 22.22d.