[Preoperative diagnostics of pancreatic neoplasms]

While patients with clinico-radiologically diagnosed resectable pancreatic cancer usually undergo surgery without preoperative cytological or histopathological diagnostics, patients with inoperable tumors or ambiguous findings in imaging often undergo EUS-FNA or EUS-FNB (endoscopic ultrasound-guided fine-needle aspiration or endoscopic ultrasound-guided fine-needle biopsy). In many cases, this concerns pancreatic cystic lesions, which can range from benign inflammatory pseudocysts to invasive pancreatic cancer emerging from intraductal papillary mucinous neoplasms (IPMNs) or mucinous cystic neoplasms (MCNs). However, the evaluation of EUS-FNA material can be especially hampered by contamination with gastric or enteric cells or mucin, degenerative changes, or low or even no cellularity of the sample. Next-generation-sequencing-based molecular analyses, especially of cystic lesions, can significantly increase the accuracy of EUS-FNA diagnostics of the pancreas. Interpretation of morphological and molecular data considering each case's clinico-radiological context is crucial. While reliable molecular markers for the detection of mucinous and specific nonmucinous pancreatic neoplasms already exist, establishing valid markers for the detection of high-grade lesions is an urgent future goal.