renal oncocytoma

Full Definition

Renal oncocytoma is a benign epithelial tumor of the kidney composed of large cells with eosinophilic, granular cytoplasm packed with mitochondria. These tumors typically present as well-circumscribed masses with a characteristic central scar on imaging. Oncocytomas can be difficult to distinguish from chromophobe renal cell carcinoma preoperatively, often requiring surgical resection for definitive diagnosis. They may occur sporadically or in association with Birt-Hogg-Dubé syndrome.

Usage

Usage note: Often shortened to 'oncocytoma' when context is clear; derived from Greek 'onkos' (swelling) and 'kytos' (cell).

In Context

• "The central stellate scar on MRI was suggestive of renal oncocytoma rather than malignancy." — Radiology report
• "Final pathology confirmed renal oncocytoma with negative margins following partial nephrectomy." — Surgical pathology report