CK7 is expressed at low levels in CCRCC, which is the most common clear-cell subtype; unusually high CK7 expression can definitely rule out the possibility of CCRCC, whereas diffuse CK7 positivity is strongly supportive of ChRCC (100%), but less certainty is reported for negative or focal staining [9]. This evidence concerns the gene KRT7 and chromophobe renal cell carcinoma.