Background. Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with rapid tumor progression and poor prognosis. This study was motivated by the lack of sensitive and specific PDAC biomarkers and aimed to identify a diagnostic, serum protein signature for PDAC. Methods. To mimic a real life test situation, a multicenter trial comprising a serum sample cohort, including 338 patients with either PDAC or other pancreatic diseases (OPD) and controls with nonpancreatic conditions (NPC), was analyzed on 293-plex recombinant antibody microarrays targeting immunoregulatory and cancer-associated antigens. Results. Serum samples collected from different hospitals were analyzed and showed that (i) sampling from five different hospitals could not be identified as a preanalytical variable and (ii) a multiplexed biomarker signature could be identified, utilizing up to 10 serum markers that could discriminate PDAC from controls, with sensitivities and specificities in the 91-100% range. The first protein profiles associated with the location of the primary tumor in the pancreas could also be identified. Conclusions. The results demonstrate that robust enough serum signatures could be identified in a multicenter trial, potentially contributing to the development of a multiplexed biomarker immunoassay for improved PDAC diagnosis.

This study was supported by VINNOVA and the SSF Strategic Center for Translational Cancer Research (CREATE Health); EU FP7 Grant Agreement 241481 (AFFINOMICS: Protein Binders for Characterization of Human Proteome Function: Generation, Validation, Application); Fondo de Investigaciones Sanitarias (FIS no. PI09-02102, no. PI12-00815, and no. PI13-00020) and Red Tematica de Investigación Cooperativa en Cancer (RTICC no. RD12/0036/0050), Instituto de Salud Carlos III (ISCIII), Spanish Ministry of Economy and Competitiveness; European Commission (EU-7FPHEALTH-259737 CANCERALIA) and European Cooperation in Science and Technology (COST Action no. BM1204: EU Pancreas).