34th European Congress of Pathology - Abstracts

Background & objectives: KRAS mutation is frequently identified in advanced colorectal carcinoma (CRC)and its prognostic significance with histological features have remained to be clarified. The aim of this study is to evaluate the clinicopathological and histomorphological characteristics in K-ras mutated patients with CRC. Methods: In this retrospective study, 420 CRC patients who underwent surgical treatment in our hospital (January 2018- December 20200 have been included. K-ras mutation testing was performed in 265 patients, detected by Cobas K-ras mutation kit to identify frequent mutations (codons 12,13,61). Clinicopathological and histomorphological data were compared with the K-ras status and correlations were evaluating using Pearson’s Chi-square test. Results: K-ras mutations were found in 148 patients (39,2%), frequently identified in older males, and in advanced stages of the disease. There was association of the K-ras mutation with the degree of tumour differentiation (G3), tumour necrosis and inflammatory response of the tumour tissue (p<0.05). No association was found between the mutational status and the tumour extention, localization, lymphonodal status and tumour type. Conclusion: According to the certain limitations of this retrospective study using a single detection kit that include common codon changes in K-ras gene it is obvious that further studies on the histological results and their prognostic value of rare KRAS codon variants are necessary. From the other perspective, the present study demonstrated a moderate association between KRAS-mutated CRCs and specific histology, and, to a certain degree, an association between histology and prognosis, according to KRAS mutation status.