Snapshot A 43-year-old woman presents to the clinic for complaints of abdominal discomfort for the past 3 weeks. He reports some dull, 3/10 pain around the epigastric region especially after he eats. His past medical history is significant for 1 episode of gallstone pancreatitis 5 weeks ago. A physical examination demonstrates an abdominal mass at the epigastric region. Introduction Clinical definition describes a circumscribed collection of fluid containing pancreatic enzymes, blood, and necrotic tissue occurring outside the pancreas the capsule is a non-epithelialized wall consisting of fibrous, granulation tissue usually develops within several weeks after the onset of pancreatitis Associated conditions acute pancreatitis alcoholism gallstone chronic pancreatitis abdominal trauma Epidemiology Demographics accounts for approximately 75% of all pancreatic masses male predominance, which mirrors the demographic distrubtion seen in pancreatitis ETIOLOGY Pathogenesis most commonly occurs following acute pancreatitis and abdominal trauma but can also occur due to chronic pancreatitis abdominal trauma is the more common cause in children can also be single or multiple, though multiple cysts are more frequently seen in patients with alcoholism the condition seems to stem from disruptions of the pancreatic duct occurs due to pancreatitis and/or extravasation of enzymatic material Presentation Symptoms abdominal pain usually with a history of pancreatitis anorexia indigestion nausea Physical exam abdominal mass tender abdomen fever scleral icterus pleural effusion peritoneal signs if cyst rupture or infection imaging Abdominal computed tomography (CT) with contrast preferred diagnostic test positive findings include a well-circumscribed fluid collection that is typically extra-pancreatic with homogenous fluid density with no internal septae Magnetic resonance imaging (MRI) more sensitive test compared to CT allows for better differentiation between pancreatic pseudocyst and other diagnosis (e.g., pseudoaneurysm) Endoscopic ultrasound (EUS) indicated in patients where the imaging findings or clinical setting is unclear/atypical can assess for features suggestive of a cystic neoplasm (e.g., internal septations) allows for treatment planning Studies Diagnostic testing diagnostic approach diagnosis is primarily based on clinical presentation and patient history and confirmed via imaging studies serum amylase and lipase may be normal or elevated serum bilirubin and liver function tests may be elevated if there is involvement of the biliary tree cystic fluid analysis low levels of carcinoembryonic antigen (CEA) and CEA-125 low fluid viscosity high amylase Differential Cystic neoplasm differentiating factors MRI can often differentiate between pseudocyst and cystic neoplasm; if the diagnosis is still uncertain, EUS and fine-needle aspiration of the fluid can be evaluated cystic fluid analysis will demonstrate high CEA-125, high fluid viscosity, and low amylase Treatment Most pseudocysts resolve without interference and require only supportive care First-line observation with follow-up imaging every 3-6 weeks supportive care nasogastric feeding if needed for pain relief proton pump inhibitor octreotide to reduce pancreatic secretions Second-line drainage of the pseudocyst is indicated in patients who are symptomatic, have rapidly enlarging pseudocysts, or have complications (e.g., infection of the cyst) endoscopic drainage preferred method of drainage complications include bleeding, performation, and secondary infection percutaneous catheter drainage higher morbidity, longer hospital stays, and longer duration of indwelling drains compared to endoscopic drainage Third-line surgery indicated in patients with infected pancreatic necrosis and symptomatic sterile necrosis Complications Bleeding/hemorrhage erosion of the pseudocyst into a vessel GI obstruction Pseudocyst rupture Peritonitis