CA9 and renal cell adenocarcinoma: In the series of Li et al. mean serum CAIX level was significantly higher in renal cell cancer patients than in healthy individuals (patients with metastatic renal cell cancer: mean 216.68 ± 67.02 pg/mL; patients with localized disease: mean 91.65 ± 13.29 pg/mL and healthy individuals: mean 14.59 ± 6.22 pg/mL).