Non-neoplastic Cysts

Question 1

What are congenital pancreatic cysts?

Answer 1

Unilocular, thin-walled cysts that arise from anomalous development of the pancreatic ducts.

Range in size from microscopic to 5cm in diameter.

Lined by uniform cuboidal epithelium, enclosed in a thin fibrous capsule and filled with a clear serous fluid.

Question 2

Whilst congenital pancreatic cysts may be sporadic, they may also be part of an inherited condition - what are two examples?

Answer 2

1. Autosomal dominant polycystic kidney disease

2. Von Hippel-Lindau disease

Question 3

What is a pancreatic pseudocyst?

Answer 3

Localised collection of necrotic and haemorrhagic material rich in pancreatic enzymes and lacking an epithelial lining (hence pseudo). Walled off by fibrous and granulation tissue, ranging from 2-30cm in diameter. Often located in the lesser omental sac, the retroperitoneum, between the stomach and transverse colon or between the stomach and liver. Sometimes within the pancreas.

Question 4

What percentage of pancreatic cysts do pseudocysts account for?

Answer 4

75%

Question 5

What are the causes of pseudocysts?

Answer 5

Usually arise following a bout of acute pancreatitis, particularly one superimposed on chronic alcoholic pancreatitis.

Traumatic injury to the pancreas can also give rise to pseudocysts.

Question 6

What is the natural history of a pseudocyst?

Answer 6

Many spontaneously resolve.

Some become secondarily infected.

Larger pseudocysts may compress or even perforate into adjacent structures.