CA9 and Familial prostate cancer: CAIX FL% was lower in controls than in urogenital cancers when taken together (p < 0.001) (Table 2) and split on the basis of tumor primary site (prostate p = 0.005; kidney p = 0.021; bladder p = 0.001) Furthermore, CAIX FL% was lower in BPH than in prostate cancer patients (p = 0.010, Figure 1).