We previously reported that high TRKB expression in head and neck squamous cell carcinoma (HNSCC) is correlated with vascular invasion and disease-free survival in patients with HNSCC and that tumor cells and tumor-associated vessels in clinical HNSCC tumors exhibit aberrant BDNF and TRKB expression14. This evidence concerns the gene NTRK2 and head and neck squamous cell carcinoma.