Table 2.

Immunohistochemical findings in spindle cell oncocytoma and the main differential diagnoses^a

Diagnoses	Immunohistochemical markers
Spindle cell oncocytoma	S-100 protein, vimentin and EMA are expressed
Oncocytic variant of meningioma	EMA is expressed, vimentin is expressed and S-100 protein is negative
Granular cell tumour	CD68 is expressed
Pituicytoma	GFAP is expressed
Oncocytic neoplasm originating from salivary gland remnants	Epithelial markers are expressed, S-100 protein and EMA are negative
Oncocytic variant of a pituitary adenoma	Synaptophysin and chromogranin are expressed

^aEMA, epithelial membrane antigen; GFAP, glial fibrillary acidic protein.