PIVKA-II: A biomarker for diagnosing and monitoring patients with pancreatic adenocarcinoma.

Abstract

Pancreatic adenocarcinoma (PDAC) is an incurable cancer without adequate tumor markers. Our previous study has showed a better diagnostic performance of Protein Induced by Vitamin K Absence II (PIVKA-II) compared to currently used PDAC biomarkers. To corroborate our previous data with a larger sample size and to assess a possible role of PIVKA-II in predicting surgical success. Additionally, to further evaluate the hypothesis of a direct PIVKA-II production by PDAC cells, we examined PIVKA-II tissue expression in a case of PDAC using immunofluorescence. We enrolled 76 newly diagnosed PDAC patients and selected 11 patients to determine PIVKA-II levels also after surgical resection. An immunofluorescence (IF) study of PIVKA-II tissue expression was carried out in one of them. PIVKA-II serum values were measured by chemiluminescent enzyme immunoassay method (CLEIA) on LUMIPULSE G1200 (Fujirebio-Europe, Belgium). PIVKA-II serum levels were above the cut-off at baseline in 71 patients (94%) with a median value of 464 mAU/Ml (range 27-40783 mAU/mL); the sensitivity and specificity were 78.67% and 90.67% respectively. Patients with pre-operative PIVKA-II positivity showed a significant decrease (P < 0.015) of median PIVKA-II serum concentrations after surgery: 820 (91-40783) mAU/mL at diagnosis vs 123 (31-4666) mAU/mL post-operatively. IF assay on PDAC sections demonstrated PIVKA-II expression in cancer cells. These data are the first showing a decreased PIVKA-II serum levels after surgery in PDAC patients and reporting PIVKA-II expression in PDAC tissue. Further studies are needed to confirm these findings and to determine PIVKA-II usefulness in diagnosing and monitoring PDAC patients.