Are Mutations of the EGFR Gene Promising Predictive Markers for Anti-EGFR mAbs in Colorectal Carcinomas?

way [6]. Nonetheless, at the present time, mutation of KRAS is the only negative molecular marker to anti-EGFR mAbs treatment [2, 5]. Recently, a somatic mutation of the EGFR kinase domain was initially reported in lung cancer and later in colorectal carcinomas. In lung cancer, mutations in the EGFR gene are associated with a high response rate to EGFR tyrosine kinase inhibitors and are prognostic for a favorable outcome. In this paper, the authors reported the incidence of the EGFR mutation in colorectal carcinomas as 22.41%. The incidence was higher than reports in Western countries, and the EGFR mutation was increased in earlier stages and in the absence of lymph node metastasis. Also exon 20 was the only mutation site, which is different from reports in Japan (mutations in exon 19 and 20). The EGFR mutation state may be an important determinant in the resistance to anti-EGFR mAbs treatment. To address this, larger studies are needed, and hopefully it will be another predictive marker for anti-EGFR mAbs therapy in mCRC [7].