[Locally invasive oncocytoma of the nasal cavity]

Reported is a nasal oncocytoma with locally invasive properties in a 86 year old man. The tumor was histologically found to consist of cells rich in cytoplasm, with striking eosinophilia, granularity, and predominance of glandular architecture. Electron microscopy revealed typical oncocytes with abundant mitochondria in the cytoplasm, with many of them compressing the nuclei of tumor cells. The tumor reported was distinguished from unambiguously benign oncocytomas by its mitotic activity and locally invasive character. These properties should be noted in histologic diagnosis. Locally delimited but radical tumor removal is the adequate therapy.