Glassy hyaline globules in granular cell carcinoma, chromophobe cell carcinoma, and oncocytoma of the kidney.

The presence of glassy hyaline globules (GHG) in renal carcinomas has been rarely emphasized in the literature. We studied the frequency of these globules in numerous renal carcinomas, including granular cell, mixed clear cell/granular cell, papillary renal cell, and chromophobe renal cell carcinoma, as well as oncocytomas. GHG are eosinophilic bodies in the hematoxylin-eosin stained sections with a size ranging from 1 to 30 micrometer and strongly positive with the periodic acid-Schiff (PAS) histochemical stain. Ultrastructurally, they are seen as amorphous secretion inside of the cisternae of the rough endoplasmic reticulum. GHG were found in 49 of 64 cases of granular cell and mixed clear cell/granular cell renal carcinomas and in 5 of 33 papillary renal cell carcinomas. No GHG were found in 22 cases of chromophobe cell carcinomas and 26 renal oncocytomas. Our findings suggests that GHG are a characteristic feature of granular cell carcinomas, mixed clear cell/granular cell renal carcinomas, and in a small minority of papillary renal cell carcinomas. In addition, it suggests that the presence of GHG in a renal cell tumor may be of aid for excluding a diagnosis of chromophobe cell carcinoma or oncocytoma.