By comparison, beta-tubulin III (TUBB3), a potential biomarker for pRCC (Fig. 2C), showed variable IHC staining in pRCC with half of cases being more than 10% positive, but staining was negative in all ccRCC and less than 10% positive in all chRCC and RO. This evidence concerns the gene TUBB3 and chromophobe renal cell carcinoma.