The CAIX fraction increased at a greaterdistance to perfused vessels, while the CD45.2 fraction decreasedfurther away from the vasculature (Figure 6C–D), indicative of chronic, diffusion-limitedhypoxia being associated with CAIX positivity and immune cell limitation.CAIX and CD45.2 fractions did not correlate to tumor size. Here, CA9 is linked to neoplasm.