EUS in drainage of pancreatic pseudocysts

Abstract

Pancreatic pseudocysts may develop as sequellae of acute or chronic pancreatitis, pancreatic trauma, or obstruction of the pancreatic duct by tumor. The pseudocyst may cause symptoms such as dyspepsia, pain, or abdominal fullness, but pseudocysts may also be asymptomatic. Severe complications such as infection, bleeding, and rupture may also occur. The natural history of a pseudocyst has been studied, and spontaneous resolution occurs in a significant number of patients, especially when the pseudocyst is of relatively small size.1,2 When pseudocysts are larger, spontaneous resolution occurs less frequently and the risk of developing complications rises. In general, small pseudocysts (6 cm or less) can be observed and do not need therapy unless indicated by symptoms. Timing of drainage of larger cysts is difficult because in acute pancreatitis even very large pseudocysts (>10 cm) can resolve completely after longer periods. Therefore the old wisdom that any pseudocyst larger than 6 cm and persistent more than 6 weeks should be drained has to be replaced by careful history taking and close observation of the pseudocysts. When symptoms worsen and/or size increases, drainage is indicated. When symptoms are minimal or diminishing and size is stable or decreasing, a “wait-and-see” policy can be adopted. Therapy for pancreatic pseudocysts can consist of surgical drainage, percutaneous drainage under radiologic guidance (transabdominal US or CTscan) or endoscopic drainage. Although surgical drainage has always been considered the reference standard, it is associated with significant morbidity (approximately 10%) and mortality (approximately 1%).3 In the past 20 years endoscopic and radiologic drainage have slowly become treatment of choice and surgery is nowadays reserved for recurrent pseudocysts or pseudocysts associated with other (pancreatic) abnormalities that require surgical therapy. It seems to be of paramount importance that patients with pancreatic pseudocysts are treated by a multidisciplinary team consisting of surgeons, radiologists, and gastroenterologists because there are specific indications for each type of procedure and these indications are also dependent on local expertise.