Here in our study, we found BEST1 was elevated on monocytes in HNSCC, different from the previous intracellular detectable proteins such as TKTL1.[55] Surface vestige of tumor education on the most abundant classical monocytes could be easily detected by flow cytometry, which made the detection easily to be adapted into clinical application. Here, TKTL1 is linked to head and neck squamous cell carcinoma.