This summary of the “state of the art” in the field of iCHT response monitoring in head and neck cancer patients shows even more negative findings reported by multiple authors, e.g., p16 protein (30–32) or FDG PET maximum-standardized uptake value (42–44) as well as inconsistent findings, e.g., primary tumor or nodal stage (14, 46, 57). This evidence concerns the gene CDKN2A and head and neck cancer.