Our team and others have reported that MUC1 (i) is consistently overexpressed in cRCC with a high expression correlated to worse prognosis [11, 18], (ii) cytoplasmic immunostaining is associated with metastatic status [11] and (iii) is a target gene of HIF-1 transcription factor which is a master key of the hypoxia pathway, the main renal carcinogenetic pathway [11]. This evidence concerns the gene MUC1 and chromophobe renal cell carcinoma.