Oncocytic carcinoma of the pancreas.

A large firm 12.5 cm mass at the tail of pancreas was surgically resected in a 73-year-old white man. The tumor was composed of solid sheets of cells with abundant finely granular eosinophilic cytoplasm. Electron microscopic study revealed tumor cells which were packed with mitochondria, a feature characteristic of the oncocyte. Perineural invasion and direct extension into the parenchyma of the spleen was present, as well as metastasis to a lymph node. There appears not to be a report of a similar case.