Mutational analysis and clinical correlation of 185 consecutive metastatic colorectal patients: Similarities and differences between colon and rectal patients| 2011 ASCO Abstract

Conclusions:

Rectal and colon patients have similar rates of KRAS and PIK3CA mutations. However, BRAF mutations are more common in colon cancer. NRAS mutations are exclusively found in rectosigmoid cancers and may have a different biology than other colorectal cancers. These data suggest that primary tumor location may provide a means to enrich a population for a genotype-directed study.