Hexokinase II positivity was associated with large tumor size (>4 cm) (r = 0.384, p = 0.046), CAIX positivity with vascular invasion (r = 0.545, p = 0.005), and MCT4 positivity with extrathyroidal extension (r = 0.418, p = 0.030) (Figure 5). This evidence concerns the gene CA9 and neoplasm.