Pancreatic Pseudocyst
l A fluid collection contained within a well-defined capsule of fibrous or granulation tissue or a combination of bothl Does not possess an epithelial liningl Persists > 4 weeks l Most common cystic lesions of the pancreas, accounting for 75-80% of such masses l Location l Lesser peritoneal sac in proximity to the pancreasl Large pseudocysts can extend into the paracolic gutters, pelvis, mediastinum, neck or scrotuml May be loculatedComposition l Thick fibrous capsule – not a true epithelial liningl Pseudocyst fluidl Similar electrolyte concentrations to plasmal High concentration of amylase, lipase, and enterokinases such as trypsinPathophysiology l Pancreatic ductal disruption 2° tol Acute pancreatitis – Necrosis l Chronic pancreatitis – Elevated pancreatic duct pressures from strictures or ductal calculi l Traumal Ductal obstruction and pancreatic neoplasmsPresentation l Symptomsl Abdominal pain > 3 weeks (80 – 90%)l Nausea / vomitingl Early satietyl Bloating, indigestionl Signsl Tendernessl Abdominal fullnessDiagnosis l CT scanl MRI / MRCPl Ultrasonographyl Endoscopic Ultrasonography (EUS)l ERCP Pseudocyst compressing the stomach wall posteriorly EUS showing pseudocyst Complications l Infection l S/S – Fever, worsening abd pain, systemic signs of sepsis l CT – Thickening of fibrous wall or air within the cavity l GI obstruction l Perforation l Hemorrhage l Thrombosis – SV (most common) l Pseudoaneurysm formation – Splenic artery (most common), GDA, PDA Treatment l Initiall NPOl TPNl Octreotidel Antibiotics if infectedl 1/3 – 1/2 resolve spontaneouslyIntervention l Indications for drainage l Presence of symptoms (> 6 wks)l Enlargement of pseudocyst ( > 6 cm)l Complicationsl Suspicion of malignancyl Intervention l Percutaneous drainagel Endoscopic drainagel Surgical drainagePercutaneous Drainage l Continuous drainage until output < 50 ml/day + amylase activity ↓ l Failure rate 16% l Recurrence rates 7% l Complications l Conversion into an infected pseudocyst (10%) l Catheter-site cellulitis l Damage to adjacent organs l Pancreatico-cutaneous fistula l GI hemorrhage Endoscopic Management l Indications l Mature cyst wall < 1 cm thick l Adherent to the duodenum or posterior gastric wall l Previous abd surgery or significant comorbidities l Contraindications l Bleeding dyscrasias l Gastric varices l Acute inflammatory changes that may prevent cyst from adhering to the enteric wall l CT findings l Thick debris l Multiloculated pseudocystsEndoscopic Drainage l Transenteric drainagel Cystogastrostomyl Cystoduodenostomyl Transpapillary drainagel 40-70% of pseudocysts communicate with pancreatic ductl ERCP with sphincterotomy, balloon dilatation of pancreatic duct strictures, and stent placement beyond stricturesSurgical Options l Excision l Tail of gland & a/w proximal strictures – distal pancreatectomy & splenectomy l Head of gland with strictures of pancreatic or bile ducts – pancreaticoduodenectomy l External drainage l Internal drainage l Cystogastrostomy l Cystojejunostomy l Permanent resolution confirmed in b/w 91%–97% of patients* l Cystoduodenostomy l Can be complicated by duodenal fistula and bleeding at anastomotic site Laparoscopic Management l The interface b/w the cyst and the enteric lumen must be ≥ 5 cm for adequate drainagel Approachesl Pancreatitis 2° to biliary etiology ® extraluminal approach w/ concurrent laparoscopic cholecystectomyl Non-biliary origin ® intraluminal (combined laparoscopic/endoscopic) approach
References Swayer et al. Pancreatic pseudocyst. http://www.emedicine.com/radio/topic576.htm Bradley III et al. A clinically based classification system for acute pancreatitis: summary of the International Symposium on Acute Pancreatitis, Arch Surg. 1993;128:586-590 Cohen et al. Pancreatic pseudocyst. In: Cameron JL, ed. Current Surgical Therapy . 7th ed.; 2001: 543-7 Gumaste et al: Pancreatic pseudocyst. Gastroenterologist 1996 Mar; 4(1): 33-43 Nealon et al, Analysis of surgical success in preventing recurrent acute exacerbations in chronic pancreatitis. Ann Surg . 2001;233:793–800 Nealon et al. Surgical management of complications associated with percutaneous and/or endoscopic management of pseudocyst of the pancreas. Ann Surg . 2005 Jun;241(6):948-57
