Correlations among KRAS Mutation, Microsatellite Instability, and (18)F-FDG Uptake in Colon Cancer

OBJECTIVE: This study aimed to evaluate the correlation of the maximum standardized uptake value (SUVmax) with the Kirsten ras sarcoma viral oncogene (KRAS) mutation and microsatellite instability (MSI) status in colon cancer. METHODS: This retrospective study included 195 patients with colon cancer who underwent (18)F-fluorodeoxyglucose positron emission tomography ((18)F-FDG PET/CT) before surgery between January 2014 and December 2017. All patients underwent KRAS mutation and MSI analyses using surgical specimens of the primary tumor. The associations of SUVmax with KRAS mutation and MSI were analyzed. RESULTS: The SUVmax differed significantly between the microsatellite stable (MSS) and MSI groups (14.5 ± 7.0 vs. 19.1 ± 10.9; P = 0.0249), and between the KRAS wild-type and KRAS mutation groups (14.1 ± 7.6 vs. 17.5 ± 7.9; P = 0.0017). CONCLUSIONS: SUVmax obtained using (18)F-FDG PET/CT showed significant differences in relation to KRAS mutation and MSI status. (18)F-FDG PET/CT could be used as a supplemental modality for assessing KRAS mutations and MSI status in colon cancer.