EGFR and colorectal carcinoma: It has been proposed that the abundance of phosphorylated EGFR (pEGFR), which reflects better the receptor utilization by tumors, could be useful to predict the response of CRC to this drug; in fact, lower levels of pEGFR detected by immunohistochemistry were found in CRC patients with a more unsatisfactory response to cetuximab-based therapy [115].