KRAS and colorectal carcinoma: Since the effect of anti-EGFR therapy on CRC is associated with KRAS status, many studies have estimated the prognostic value of KRAS status in CRC patients [8–10], and some studies showed that mutation of KRAS indicated a poor prognosis of CRC patients, but there were also some reports have failed to show the similar result [14–17, 19], thus, the current conclusions regarding the prognostic value of KRAS status remain inconclusive.