RAS mutations in patients with metastatic colorectal cancer in Central America and the Caribbean.

Abstract

e15126 Background: Metastatic colorectal cancer (MCRC) survival has been improved in the last decade due to the identification of predictive and prognostic factors such as RAS gene status and also by the addition of targeted therapies to chemotherapy schemes. RAS mutation, a prognostic factor but must importantly a predictive factor for tumor response to monoclonal antibodies against the epidermal growth factor receptor in MCRC, has been reported between 16.3% and 43.6%. The aim of this study is to determine the frequency of RAS mutations in patients with MCRC in Central America and the Caribbean. Methods: This is a retrospective-descriptive analysis of RAS mutations performed in patients with MCRC in Central America and the Caribbean. An informed consent was required for the mutational analysis. The information obtained has been kept in an anonymized database. Results: 2,138 tissue samples were analyzed by real time PCR. RAS mutations were documented in 46.7% of the cases, of these 94.8% correspond to mutations in kRAS and 5.2% to mutations in nRAS. 67.5% of RAS mutations were found in codon 12, 21.3% in codon 13, 5.8% in codon 146 and 4% in codon 61. 51.5% of the mutations were in males and 48.5% in females. RAS mutations in central american population were identified in a 45.8% and in a 42.5% in the caribbean. Conclusions: This is the first report of RAS mutations in patients with MCRC in Central America and the Caribbean. Our findings are similar to the data reported in other regions of the world. A clinical and epidemiological analysis and correlation of these findings is underway.