Coexistence of <i><i>KRAS</i></i> and <i>BRAF</i> Mutations in Colorectal Cancer: A Case Report Supporting The Concept of Tumoral Heterogeneity.

Abstract

The detection of <i>KRAS</i> and <i>BRAF</i> mutations is a crucial step for the correct therapeutic approach and predicting the epidermal growth factor receptor (EGFR)-targeted therapy resistance of colorectal carcinomas. The concomitant <i>KRAS</i> and <i>BRAF</i> mutations occur rarely in the colorectal cancers (CRCs) with the prevalence of less than 0.001% of the cases. In patients with <i>KRAS</i>-mutant tumors, <i>BRAF</i> mutations should not regularly be tested unless the patient is participating in a clinical trial enriching for the presence of <i>KRAS</i> or <i>BRAF</i>-mutated tumor. The current report demonstrates a case with advanced adenocarcinoma of the colon showing the coexistence of <i>KRAS</i> and <i>BRAF</i> mutations and may have profound clinical implications for disease progression and therapeutic responses.