EGFR and colorectal cancer: Therefore, the advantage in meaningful clinical activity of cetuximab over panitumumab in SCCHN may be partially attributed to their effects beyond EGFR inhibition (notably, panitumumab is a very potent EGFR inhibitor), i.e., to the differential induction of immune response, which seems to be highly relevant in SCCHN (Figure 2) but less relevant in colorectal cancer.