A. Jouret-Mourin MD, PhD, C. Cuvelier MD, PhD, P. Demetter MD, PhD, N. D’Haene MD, PhD, A. Driessen MD, PhD, A. Hoorens MD, PhD, N. Nagy MD, X. Sagaert MD, P. Pauwels MD, PhD, On behalf of the Working Group of Digestive Pathology and the Belgian Society of Pathology.
There is an urgent need for predictive biomarkers in several cancers. In colorectal cancers, KRAS exon 2 mutation analyses were mandatory when considering anti-epidermal growth factor antibody therapy with agents such as cetuximab or panitumumab. However, since the introduction of this testing, a cohort of patients still did not appear to benefit from this therapy. Recently, additional testing for KRAS exon 3 and 4, and NRAS considerably improved the predictive power for therapy success. Therefore, an update of the Belgian guidelines for RAS testing was urgently needed.