Supplementary Material for: Colorectal Cancer with BRAF D594G Mutation Is Not Associated with Microsatellite Instability or Poor Prognosis

Abstract

<i>Objective:</i><i>BRAF</i> D594G mutations in colorectal cancer patients are not clearly understood. We retrospectively investigated the clinicopathological features of colorectal cancers with <i>BRAF</i> D594G mutations. <i>Methods:</i> We selected 908 colorectal cancer patients who underwent surgical resection from January 2008 to January 2013, and assessed <i>BRAF</i>, <i>KRAS</i>, microsatellite instability, and CpG island methylator phenotype (CIMP). <i>Results:</i> We detected <i>BRAF</i> D594G in 7 patients and <i>BRAF</i> V600E in 45 patients. The clinicopathological features of cancers with <i>BRAF</i> D594G mutation were similar to those with <i>BRAF</i> wild-type, but differed from those with <i>BRAF</i> V600E mutations. Regarding microsatellite instability status, 44.4% of cases with <i>BRAF</i>V600E mutations exhibited high microsatellite instability, compared to 14.3% of those with <i>BRAF</i> D594G mutations and 4.4% of those with <i>BRAF</i> wild-type. There were no CIMP-positive tumors in cancers with <i>BRAF</i> D594G mutations, whereas 67.8% of tumors with <i>BRAF</i> V600E mutations were CIMP-positive. In stage IV cancers, the survival rates of patients at 2 years were 8.5, 50.0, and 68.2% in the <i>BRAF</i> V600E mutation, <i>BRAF</i> D594G mutation, and <i>BRAF</i> wild-type groups, respectively.<i>Conclusion:</i> Colorectal cancers with <i>BRAF</i> D594G mutations exhibit similar clinicopathological features, microsatellite instability status, and prognosis as those with <i>BRAF</i> wild-type