P-0177 - KRAS Mutation Status in Colombian patients with colorectal cancer. Analysis of 1104 consecutive cases

Date 28 June 2014
Event World GI 2014
Session Poster Session
Topics Diagnostics
Colon Cancer
Rectal Cancer
Presenter Rocio Lopez Panqueva
Citation Annals of Oncology (2014) 25 (suppl_2): ii14-ii104. 10.1093/annonc/mdu165
Authors D. Cañon1, N. Ospina2, L. Vasquez1, L. Barrera3, J. Alvarez4
  • 1Fundación Santa Fe de Bogotá, Bogotá/CO
  • 2Fundación Santa Fe de Bogota, Bogotá/CO
  • 3Fundacion Santa Fe de Bogota, Bogota/CO
  • 4Fundacion Santa Fe de Bogota, Bogotá/CO

Abstract

Introduction

Colorectal cancer (CRC) is the third most common type of cancer in women and the fourth among men worldwide. The KRAS oncogene mutational status is used as a biomarker in CRC. It is estimated that almost 40% of patients present mutations at codons 12 and 13 of the genes and became resistant to treatment with Epidermal Grow Factor Receptor (EGFR) inhibitors.

Methods

Between January 2009 and December 2013, 1104 consecutive samples were analyzed with a confirmed CRC diagnosis; direct sequencing from embedded tissue paraffin assessed the mutational status of codons 12 and 13 of the KRAS gene.

Results

The mean age of patients was 56 years (16-87 years), 51.4% were female and 48.6% male. The percentage of wild and mutated KRAS was 64.2% and 35.8% in women and 62.4% and 33.6% respectively in men. No statistically significant association in the percentage of patients with mutated KRAS and gender (p > 0.05) was found. From the 383 mutated cases, 75% were in codon 12 versus the remaining 25% in codon 13. In the group of women and men no differences between frequencies of mutations in codon 12 and 13 (74.4 and 25.6% in women and 75.5 and 24.5% in men) were found. Patients were grouped according age (≤ 49, 50-64 and ≥ 65 years) and no statistically significant differences between each of these groups and KRAS status was noted. In 93% of cases the material was suitable for molecular studies.

Conclusion

The KRAS status in Colombian patients is similar to the reported in other populations. Additionally, different from other studies with higher mutations percentage described in women, we found no differences in percentages between mutation in codons 12 and 13 of the KRAS in both men and women; patients age was not associated with oncogene mutational status.