CA9 and neoplasm: The comparison of KRAS mutant and wild-type tumor groups confirmed significant differences as KRAS mutant samples presented with much higher CAIX scores and the correlation of CAIX expression proved to be statistically significant in NAT biopsies, surgical samples, and UT biopsies, but not in UT surgical samples, according to the Fisher’s exact test (p < 0.05) (Figure 7A–D).