To clarify the anti-tumor efficacy of the blockade of BDNF/TrkB signaling in CRC, we would first need to confirm whether a BDNF blockade, such as an anti-BDNF antibody, and a TrkB blockade, such as a pharmacological pan-Trk inhibitor or an antagonistic anti-TrkB antibody, show anti-tumor effects on CRC in patients with various BDNF/TrkB expression statuses. This evidence concerns the gene NTRK2 and colorectal carcinoma.