The incidence of kras mutati̇on in colon adenocarci̇noma and association with LYMPH node metastasis

Colon cancer is the most common malignancy of the gastrointestinal tract and one of the main cause of mortality and morbidity. Latest point reached in the treatment of colorectal cancer is the use of EGFR-targeted agents. RAS mutation status plays a considerable role in decisions about treatment. In cancer, 90% of RAS mutations occur in the KRAS gene. Most of KRAS mutations are described in codon 12, 13, 59 and 61. In case of KRAS gene mutations in codons 12 and 13 they do not respond to the treatment of EGFR-targeted agents, of the wild-type KRAS gene are known to be suitable candidates for the treatment. Mutation screening before starting treatment is important because KRAS gene mutations are seen by 30-40% of colorectal cancers. A total of 120 moderately differentiated colon adenocarcinoma samples, 60 cases withv lymph node metastases and 60 without lymph node metastasis were taken from Firat University Faculty of Medicine Department of Pathology archives. In our study, KRAS mutation rate was seen by 35% of patients without lymph node metastasis (21/60), 40% with lymph node metastases (24/60) and 37.5% (45/120) in all cases. KRAS mutation rate was higher at patients with lymph node metastasis than without metastases, but there were no statistically significant differences (p> 0.05). KRAS mutations were detected as 33.3% of all cases in codons 12, 4.1% in codon 13; at patients without lymph node metastases 30% in codon 12, 5% in 13 codon; at patients with lymph node metastases of 36.6% codons 12 and 3.3% codon 13. There was no statistically significant difference between the groups in terms of distribution of KRAS mutations codon 12 and codon 13 (p> 0.05). In conclusion; In our study, KRAS mutations were observed 37.5% percentage at moderately differentiated adenocarcinomas of the colon, as 33.3% in codon 12, and 4.1% in codon 13. KRAS codon 61 mutation was not observed. There was no significant correlation between lymph node metastases with KRAS mutations.