Clinical implication of KRAS mutation variants in patients with resected colon cancer.

Abstract

179 Background: This study evaluated the clinical implication of KRAS mutation variants in patients with resected colon cancer (CC). Methods: We retrospectively reviewed 482 patients diagnosed with CC and underwent curative surgical resection at Kyungpook National University Chilgok Hospital. The inclusion criteria were: pathologically diagnosed with primary CC; stage I–III CC according to the 7th edition of American Joint Committee on Cancer staging system; and with available test results for KRAS mutation status. In total, 345 patients met these criteria and were included in this study. Results: Among the 345 patients, 140 (40.6%) exhibited KRAS mutations, with their incidences as follows: 90/140 (64.3%) in Exon 2 Codon 12, 37/140 (26.4%) in Exon 2 Codon 13, 1/140 (0.1%) in Exon 3 Codon 59, 7/140 (5.0%) in Exon 3 Codon 61, and 5/140 (3.6%) in Exon 4 Codon 146. KRAS mutation status was not a significant prognostic factor for disease-free survival (DFS) or overall survival (OS). Although, there were no significant differences in survival between patients with Exon 2 Codon 12 and Exon 2 Codon 13 mutations, poorer DFS ( p = 0.085) and OS ( p = 0.005) were seen in those with Exon 3 Codon 61 mutation than in others. Conclusions: KRAS mutation status was not correlated with survival, but Exon 3 Codon 61 mutation might be a poor prognostic factor in resected CC patients.