The emerging role of endoscopic ultrasound-guided core biopsy for the evaluation of solid pancreatic masses.

Pancreatic ductal adenocarcinoma is a lethal cancer with a 5-year survival rate of less than 5%. Surgical resection is the only curative treatment but only 20% are eligible for resection at the time of diagnosis. Early detection of cancer is of paramount importance in the management. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is the preferred modality for obtaining tissue diagnosis of pancreatic masses. However, the diagnostic accuracy of EUS-FNA may be limited by several factors like availability of onsite cytopathology, adequacy of tissue core for histology, location of the mass, presence of underlying chronic pancreatitis, and experience of the endoscopist. Modern oncology is focusing on personalizing treatment based on tissue analysis of genetic aberrations and molecular biomarkers which are now available. Core tissue also aids in the diagnosis of disease entities like lymphoma, metastatic tumors, neuroendocrine tumors and autoimmune pancreatitis whose diagnosis rely on preserved tissue architecture and immunohistochemistry. Making accurate diagnosis of solid pancreatic masses is critical to avoid unnecessary resections in patients with benign lesions like focal lesions of chronic pancreatitis and autoimmune pancreatitis which mimic cancer. To overcome the limitations of FNA and to obtain adequate core tissue, a Tru-Cut biopsy needle was developed which met with variable success due to stiffness, cumbersome operation and technical failure using it in the duodenum/pancreatic head. More recently fine needle biopsy needles, with reverse bevel technology have become available in different sizes (19, 22, 25-gauge). The aim of this article was to review the emerging role of core biopsy needles in acquiring tissue in solid pancreatic masses and discuss its potential role in personalized medicine.