High expression of the ligands of EGFR, epiregulin (EREG) and amphiregulin (AREG) at the RNA level was deemed highly predictive of therapeutic benefit with the antiEGFR agent panitumumab in KRAS/NRAS wildtype metastatic CRC in the PICCOLO trial (International Standard Randomised Controlled Trial Number (ISRCTN): 93248876)7, 10; however, routine assessment of these or other predictive tissue biomarkers is not routinely performed in CRC. Here, EREG is linked to colorectal carcinoma.