Diagnostic evaluation of pancreatic cystic malignancies.

Cystic neoplasms of the pancreas are increasingly recognized because of expanding use and improved sensitivity of cross-sectional imaging studies. Major advances in the last decade have led to an improved understanding of the various types of cystic lesions and their biologic behavior. Despite significant improvement in imaging technology and the advent of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) the diagnosis and management of pancreatic cystic lesions remains a significant clinical challenge. Previous "operate in all cases of pancreatic cyst" strategies have been refined and largely replaced using EUS and cyst fluid analysis as the crux for a more practical management approach. The first diagnostic step remains the differentiation between pancreatic pseudocyst and cystic neoplasm. If a pseudocyst has been effectively excluded, the cornerstone issue becomes to determine the malignant potential of the pancreatic cystic neoplasm. In most cases the correct diagnosis and successful management is based not on a single test but on incorporating data from various sources including patient history, radiologic studies, endoscopic evaluation, in particular EUS, and cyst fluid analysis obtained during fine-needle aspirate. This review focuses on describing the various types of cystic neoplasms of the pancreas and their malignant potential, and provide the clinician with a comprehensive diagnostic approach.