Borderline Resectable and Locally Advanced Pancreatic Cancers: A Review of Definitions, Diagnostics, Strategies for Treatment, and Future Directions.

ABSTRACT Locally advanced and borderline resectable pancreatic cancers are being increasingly recognized as a result of significant improvements in imaging modalities. The main tools used in diagnosis of these tumors include endoscopic ultrasound, computed tomography, magnetic resonance imaging, and diagnostic laparoscopy. The definition of what constitutes a locally advanced or borderline resectable tumor is still controversial to this day. Borderline resectable tumors have been treated with neoadjuvant therapy approaches that aim at reducing tumor size, thus improving the chances of an R0 resection. Both chemotherapy and radiotherapy (solo or in combination) have been used in this setting. The main chemotherapy agents that have shown to increase resectability and survival are FOLFORINOX (a combination of folinic acid, fluorouracil, irinotecan, and oxaliplatin) and gemcitabine-nab-paclitaxel. Surgery on these tumors remains a significantly challenging task for pancreatic surgeons. More studies are needed to determine the best agents to be used in the neoadjuvant and adjuvant settings, biologic markers for prognostic and operative predictions, and validation of previously published retrospective results.