Quantitative detection and the significance of K-ras12 and K-ras13 mutations in peripheral blood of the population with high risk of pancreatic cancer / 中华消化杂志

ABSTRACT

Objective To explore the clinical significance of the detection of K-ras12 and K-ras13 mutations in the peripheral blood of population with high risk group of pancreatic cancer.Methods From May 2010 to November 2011,a total of 160 patients with clear diagnosis and high risk of pancreatic cancer were collected.Among those patients,36 cases were finally diagnosed as pancreatic cancer,36 cases were chronic pancreatitis (CP),six cases were autoimmune pancreatitis (AIP),16 cases were other malignant tumor,13 cases were pancreatic benign tumor,13 cases were bile duct stones and 40 cases were other benign diseases.Fasting peripheral venous blood was collected in all selected candidates.The condition of K-ras12 and K-rasl3 mutation was detected by peptide nucleic acid-mediated real time fluorescen quantitative polymerase chain reaction.Mann-Whitney U test was performed to compare the mutation between the two groups.Chi-square test was used to compare the rates.According to the receiver operator characteristic (ROC) curve,the mutation positive decision value and the mutation positive rate of K-ras12 and K-ras13 were calculated.Results There were significant differences in K-ras12 mutation between pancreatic cancer group (1154(2207)) and other benign diseases (476(973)),CP group (446(808)),bile duet stones group (357(568)) (U=502,446 and 117,all P＜0.05).There were no significant differences in K-ras13 mutation between pancreatic cancer group and other benign diseases,CP group,bile duct stones group (all P＞0.05).When the mutation positive decision value of K-ras12 was set as mutation copy over 1000,the positive mutation rate of pancreatic cancer and non-pancreatic cancer was 55.6％ (20/36) and 25.0％ (31/124),respectively.When the area under the ROC curve of K-ras12 was 0.664,there was differential diagnostic value in identifying pancreatic cancer and non-pancreatic cancer (P=0.003).When the area under the ROC curve of K-ras13 was 0.522,there was no differential diagnostic value in identifying pancreatic cancer and non-pancreatic cancer (P=0.695).There was significant difference in K-ras13mutation between smokers and non-smokers (943 (1510) and 571 (964)).Conclusion K-ras12mutation in peripheral venous blood may be used for pancreatic cancer screening.