Relationship Between KRAS Mutation and Diffusion Weighted Imaging in Colorectal Liver Metastases; Preliminary Study

Abstract Purpose We aimed to investigate whether there are any differences in apparent diffusion coefficient (ADC) values obtained from colorectal liver metastases (CRLM) according to Kirsten rat sarcoma (KRAS) gene mutation status. Method In this retrospective study, we included 22 patients with 65 liver metastases due to colorectal cancer and performed KRAS gene mutation tests. We divided the patients into two groups as KRAS mutation positive (+) (n:10, 30 lesions) and the wild-type group (n:12, 35 lesions). In the comparisons of the ADC and ADCmean values of the two groups, the Mann-Whitney U test was used. In addition, we performed receiver-operating characteristic (ROC) analysis of the discrimination of the two groups in terms of their ADC and ADCmean values. Results The ADC and ADCmean values were found to be statistically significantly lower in the KRAS (+) group compared to the wild-type group. ROC curve analysis revealed a statistically significant difference in terms of ADC and ADCmean with area under the curve (AUC) values of 0.680 and 0.760, respectively. The cut-off values for ADC and ADCmean were 986 × 10-6  mm2/s and 823 × 10-6  mm2/s, respectively. Conclusion In our study, the lower ADC and ADCmean values of CRLM are associated with presence of KRAS mutation. ADC and ADCmean values derived from liver metastases due to the colorectal cancer can be used to differentiate KRAS mutation status.