Combination of plasma microRNAs with serum CA19‐9 for early detection of pancreatic cancer

This study was performed to identify plasma microRNAs (miRNAs) as diagnostic biomarkers for pancreatic cancer (PCa) and to assess their supplementary role with serum CA19-9 in early identification of tumors. Plasma RNAs were extracted from 140 PCa patients, 111 chronic pancreatitis (CP) patients and 68 normal controls, and the relative abundances of seven miRNAs (miR-16, 21, 155, 181a, 181b, 196a and 210) were measured using real-time PCR. Their diagnostic utility for PCa and correlation with clinical characteristics were analyzed. All seven miRNAs were significantly aberrantly upregulated in the PCa group compared with both the CP and normal groups, between which only four miRNAs (miR-155, 181a, 181b and 196a) were significantly different. Logistic modeling proved that only miR-16 and miR-196a possessed an independent role in discriminating PCa from normal and CP. Furthermore, after including serum CA19-9 in the logistic model, the combination of miR-16, miR-196a and CA19-9 was more effective for discriminating PCa from non-PCa (normal+CP) (AUC-ROC, 0.979; sensitivity, 92.0%; specificity, 95.6%), and for discriminating PCa from CP (AUC-ROC, 0.956; sensitivity, 88.4%; specificity, 96.3%) compared with the miRNA panel (miR-16+miR-196a) or CA19-9 alone. Most significantly, the combination was effective at identification of tumors in Stage 1 (85.2%). In conclusion, plasma miRNAs were effective for distinguishing PCa from non-PCa (normal+CP). The combination of miR-16, miR-196a and CA19-9 was more effective for PCa diagnosis, especially in early tumor screening.