KRAS and colorectal carcinoma: First, a recent retrospective analysis of multiple phase-III trials unexpectedly concluded that patients with KRAS codon 13 mutation (G13D) seem to benefit from the treatment [6], and our recent observation on a mouse clinical trial (MCT) using a cohort of randomly selected CRC patient-derived xenografts (PDXs) also clearly supported the same conclusion [7, 8].