CA9 and neoplasm: For the combined treatment arm analyses of IHC tumor biomarkers, there were no statistically significant associations between TTP and OS with either HIF-1α or CA-IX percent of tumor expression; however, in the analysis of HIF-1α percent of tumor expression, PFS was statistically significantly different between groups 0–2 (i.e., 0–50 % or low expression) versus groups 3–4 (i.e., 51–100 % or high expression) before multiple testing.