Pancreatic ductal adenocarcinoma (PDAC) is the fourth most common cause of cancer-related death with a 5-year survival rate of <5% (Siegel et al. 2016). In contrary to many other forms of cancer the incidence of PDAC is rising and predicted to become the 2nd most common cause of cancer-related death by 2030 (Rahib et al. 2014). Its lethality can be attributed to late diagnosis, almost complete resistance to conventional chemo- and radiotherapy, and a lack of diagnostic biomarkers. Unlike breast or colorectal cancer, the only treatment with curative intent is surgery, for which < 20% of patients qualify; but even then the chance of survival is very low (Lohr 2006). Therefore, PDAC should be treated as a medical emergency (Lohr 2014). Risk factors for PDAC include chronic pancreatitis (CP) and around 5% of CP patients develop PDAC over time (Pinho et al. 2014; Garrido-Laguna and Hidalgo 2015). Both PDAC and CP are characterized by an excessive and reactive stroma, or desmoplasia, which makes it difficult to distinguish between the two conditions (Kloppel and Adsay 2009). The one FDA-approved biomarker for PDAC, carbohydrate antigen 19-9 (CA 19-9), is only useful for prognosis and detection of disease recurrence (Fong and Winter 2012). Therefore there is an urgent clinical need of a non-invasive diagnostic biomarker for PDAC.