This study aimed to: (1) Identifying KRAS mutation in ctDNA (mutKRAS ctDNA) in patients with pancreatic cancer (PC) and thoses with benign pancreatic diseases using ddPCR; (2) Investigating the association between mutKRAS ctDNA and the clinical stages of PC. Materials and methods: 49 patients with PC and 47 patients with benign pancreatic diseases were measured mutKRAS ctDNA using ddPCR. Results: The positive mutKRAS ctDNA accounted for 69.4% in the PC group, which was statistically significantly higher than that in the benign pancreatic tumor/cyst group (21.1%) and the chronic pancreatitis group (7.1%), p<0.0001. KRAS mutant allele fraction (KRAS MAF) in ctDNA associated with the clinical stages of PC categorized by the TNM staging system, the mean KRAS MAF in ctDNA of the stage IV group was 8.4 ± 12.2%, which was statistically significantly higher than that of stage III group (2.8 ± 2.4%) and stage I-II group (1.1 ± 1.6%). The KRAS MAF had predictive significance for metastatic PC, with a cut-off value > 5.55%, AUC=0.739, p=0.019. Conclusion: ddPCR identified a significant prevalence of patients with PC harboring mutKRAS ctDNA. The KRAS MAF in ctDNA had the prognostic value for severe progression in PC.

This study aimed to: (1) Identifying KRAS mutation in ctDNA (mutKRAS ctDNA) in patients with pancreatic cancer (PC) and thoses with benign pancreatic diseases using ddPCR; (2) Investigating the association between mutKRAS ctDNA and the clinical stages of PC. Materials and methods: 49 patients with PC and 47 patients with benign pancreatic diseases were measured mutKRAS ctDNA using ddPCR. Results: The positive mutKRAS ctDNA accounted for 69.4% in the PC group, which was statistically significantly higher than that in the benign pancreatic tumor/cyst group (21.1%) and the chronic pancreatitis group (7.1%), p<0.0001. KRAS mutant allele fraction (KRAS MAF) in ctDNA associated with the clinical stages of PC categorized by the TNM staging system, the mean KRAS MAF in ctDNA of the stage IV group was 8.4 ± 12.2%, which was statistically significantly higher than that of stage III group (2.8 ± 2.4%) and stage I-II group (1.1 ± 1.6%). The KRAS MAF had predictive significance for metastatic PC, with a cut-off value > 5.55%, AUC=0.739, p=0.019. Conclusion: ddPCR identified a significant prevalence of patients with PC harboring mutKRAS ctDNA. The KRAS MAF in ctDNA had the prognostic value for severe progression in PC.