Chromophobe renal cell carcinoma with extensive calcification and ossification.

A 39-year-old woman presenting with microscopic hematuria was found to have an extensively calcified mass in the upper pole of the right kidney. Gross and histologic examination of the nephrectomy specimen revealed a 9.3-cm renal tumor composed of solid trabecular sheets of polygonal epithelial cells with clear cytoplasm and distinct cell borders characteristic of a chromophobe renal cell carcinoma. Electron microscopy showed the presence of numerous intracytoplasmic microvesicles, thereby confirming the diagnosis. However, the unique additional feature of this tumor included the presence of dense calcification and ossification throughout the tumor. To our knowledge, we report the first case of chromophobe renal cell carcinoma with the concomitant presence of extensive calcification and ossification. A literature review on chromophobe renal cell carcinoma with either calcification or ossification is performed. Copyright 2002, Elsevier Science (USA). All rights reserved.