Pancreatic Pseudocyst
l A fluid collection contained within a well-defined capsule of fibrous or granulation tissue or a combination of both
l Does not possess an epithelial lining
l Persists > 4 weeks
l May develop in the setting of acute or chronic pancreatitis
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 pancreas
l Large pseudocysts can extend into the paracolic gutters, pelvis, mediastinum, neck or scrotum
l May be loculated
Composition
l Thick fibrous capsule – not a true epithelial lining
l Pseudocyst fluid
l Similar electrolyte concentrations to plasma
l High concentration of amylase, lipase, and enterokinases such as trypsin
Pathophysiology
l Pancreatic ductal disruption 2° to
l Acute pancreatitis – Necrosis
l Chronic pancreatitis – Elevated pancreatic duct pressures from strictures or ductal calculi
l Trauma
l Ductal obstruction and pancreatic neoplasms
Presentation
l Symptoms
l Abdominal pain > 3 weeks (80 – 90%)
l Nausea / vomiting
l Early satiety
l Bloating, indigestion
l Signs
l Tenderness
l Abdominal fullness
Diagnosis
l CT scan
l MRI / MRCP
l Ultrasonography
l 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 Initial
l NPO
l TPN
l Octreotide
l Antibiotics if infected
l 1/3 – 1/2 resolve spontaneously
Intervention
l Indications for drainage
l Presence of symptoms (> 6 wks)
l Enlargement of pseudocyst ( > 6 cm)
l Complications
l Suspicion of malignancy
l Intervention
l Percutaneous drainage
l Endoscopic drainage
l Surgical drainage
Percutaneous 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 pseudocysts
Endoscopic Drainage
l Transenteric drainage
l Cystogastrostomy
l Cystoduodenostomy
l Transpapillary drainage
l 40-70% of pseudocysts communicate with pancreatic duct
l ERCP with sphincterotomy, balloon dilatation of pancreatic duct strictures, and stent placement beyond strictures
Surgical 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 drainage
l Approaches
l Pancreatitis 2° to biliary etiology ® extraluminal approach w/ concurrent laparoscopic cholecystectomy
l 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
