SUVmax and metabolic tumor volume: surrogate image biomarkers of KRAS mutation status in colorectal cancer

Abstract
Purpose: The objective of this study was to explore the association between KRAS mutation status and PET/CT metabolic parameters in colorectal cancer (CRC) patients. Materials and methods: One hundred and sixty-four CRC patients were enrolled in this study and received PET/CT examination before operation, then KRAS mutation status was analyzed through pathologically confirmed CRC samples. The association between tumor clinical characteristics and PET/CT metabolic parameters, including maximum standardized uptake value (SUVmax), SUVmean, and metabolic tumor volume (MTV), and KRAS mutation status was analyzed using chi-squared tests, Mann–Whitney U tests, and logistic regression analysis. Results: The KRAS mutation type patients exhibited high MTV and high SUVmax using a threshold of 17.8 cm3 and 8.7 respectively and the predictive accuracy was 0.772 and 0.603 respectively. High MTV (P=0.001; 95% CI: 1.119–1.296) and high SUVmax (P=0.048; 95% CI: 0.564–0.985) were independent predictors for KRAS mutation status. Conclusion: MTV and SUVmax were associated with KRAS mutation type in CRC patients. PET/CT metabolic parameters can be used for supplementing KRAS mutation status prediction in CRC patients.