This rare neoplasm of the kidney is called angiomyolipoma. Note that it is solid and has a tan to yellowish-tan cut surface. It is also multifocal (a smaller nodule appears in the upper pole. Most of these tumors are incidental findings, but persons with a rare condition known as tuberous sclerosis often have these tumors. This neoplasm is one form of perivascular epithelioid cell tumor (PEComa) derived from the perivascular epithelioid cell (PEC), as elusive as the yeti, and not present in normal tissue. [Image contributed by John Nicholls, MD, Hong Kong University]