Abstract

A pancreatic pseudocyst is a circumscribed collection of fluid rich in pancreatic enzymes, blood, and necrotic tissue, typically located in the lesser sac of the abdomen. Pancreatic pseudocysts are usually complications of pancreatitis, although in children they frequently occur following abdominal trauma. Pancreatic pseudocysts account for approximately 75% of all pancreatic masses.

Signs/symptoms

Signs and symptoms of pancreatic pseudocyst include abdominal discomfort and indigestion.

Signs/symptoms | Complications

Complication of pancreatic pseudocyst include infection, hemorrhage, obstruction and rupture. For obstruction, it can cause compression in the GI tract from the stomach to colon, compression in urinary system, biliary system, and arteriovenous system.

Causes

The cause of pancreatic pseudocyst can occur due to a variety of reasons, among them pancreatitis (chronic), pancreatic neoplasm and/or pancreatic trauma.

Pathophysiology

Pancreatic pseudocysts are sometimes called false cysts because they do not have an epithelial lining.The wall of the pseudocyst is vascular and fibrotic, encapsulated in the area around the pancreas. Pancreatitis or abdominal trauma can cause its formation. Treatment usually depends on the mechanism that brought about the pseudocyst. Pseudocysts take up to 6 weeks to completely form.

Diagnosis

Diagnosis of Pancreatic pseudocyst can be based on cyst fluid analysis:

- Carcinoembryonic antigen (CEA) and CEA-125 (low in pseudocysts and elevated in tumors);

- Fluid viscosity (low in pseudocysts and elevated in tumors);

- Amylase (usually high in pseudocysts and low in tumors)

The most useful imaging tools are:

- Ultrasonography – the role of ultrasonography in imaging the pancreas is limited by patient habitus, operator experience and the fact that the pancreas lies behind the stomach (and so a gas-filled stomach will obscure the pancreas).

- Computerized tomography – this is the gold standard for initial assessment and follow-up.

- Magnetic resonance cholangiopancreatography (MRCP) – to establish the relationship of the pseudocyst to the pancreatic ducts, though not routinely used

Treatment

Pancreatic pseudocyst treatment should be aimed at avoiding any complication (1 in 10 cases become infected). They also tend to rupture, and have shown that larger cysts have a higher likelihood to become more symptomatic, even needing surgery. If no signs of infection are present, initial treatment can include conservative measures such as bowel rest (NPO), parenteral nutrition (TPN), and observation. Serum amylase levels can be trended. If symptoms do not improve by 6 weeks, surgical intervention may be appropriate.

In the event of surgery:

- Cystogastrostomy: In this surgical procedure a connection is created between the back wall of the stomach and the cyst such that the cyst drains into the stomach.

- Cystjejunostomy: In this procedure a connection is created between the cyst and the small intestine so that the cyst fluid directly into the small intestine.

- Cystduodenostomy: In this procedure a connection is created between the duodenum (the first part of the intestine) and the cyst to allow drainage of the cyst content into duodenum. The type of surgical procedure depends on the location of the cyst. For pseudocysts that occur in the head of the pancreas a cystduodenostomy is usually performed.