Relationship between PET/CT images and KRAS gene mutations in colorectal cancer in Vietnamese patients.

OBJECTIVE: We conducted this study to determine the relationship among standardized uptake value (SUV), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) indexes of Flourine-18 fluorodeoxyglucose positron emission tomography/computed tomography18 (FDG-PET/CT) imaging and Kirsten rat sarcoma (KRAS) gene mutations in colorectal cancer (CRC).

PATIENTS AND METHODS: This cross-sectional study was conducted in Bach Mai Hospital from 2020 to 2022. It included newly diagnosed CRC patients who underwent PET/CT examination prior to primary tumor resection. The maximum SUV (SUVmax - SUVmean), MTV, and TLG were considered. All pathologically confirmed CRC patients were accepted with further KRAS mutation status analysis.

RESULTS: We enrolled 63 newly diagnosed CRC patients who underwent PET/CT examination prior to primary tumor resection. Among them, 31 (49.2%) patients had KRAS gene mutation. Patients with KRAS mutation status showed significantly different and higher SUVmax (p-value = 0.025), SUVmax t/b (p-value = 0.013), SUVmax t-b (p-value = 0.014), MTV (p-value = 0.023), and TLG (p-value = 0.011) than patients with WT KRAS. Other characteristics, including age, gender, tumor location, SUVb, SUVmean, SUVmax of lymph nodes, and SUVmax of liver metastasis, were insignificantly different between the two groups of patients with KRAS mutation status. Receiver operating curve analysis showed that the area under the curve was 0.672 for SUVmax (p-value = 0.019), SUVt/b (p-value = 0.045), and SUVt-b (p-value = 0.020).

CONCLUSIONS: We observed a relationship, considering the quantitative parameters (SUVmax, SUVmax, SUVmax t-b, MTV, and TLG), between 18FDG-PET/CT images and the KRAS gene mutation in CRC by analyzing 63 patients prior to treatment.