Analysis of the serum levels of BDNF revealed that the serum level of BDNF in patients with CRC (10.64 ± 3.84 ng/mL) was significantly higher than the level in HC (4.69 ± 1.69 ng/mL; p < 0.0001) and patients with adenomas (5.97 ± 2.09 ng/mL; p < 0.001) (Figure 1(a)). Here, BDNF is linked to adenoma.