Non-neoplastic pancreatic cysts: congenital cysts and pseudocysts
- Lesion
A pseudocyst is a pocket of pancreatic fluid walled off by scar after pancreatitis; it has no lining of cells.
What it is
Most cystic lesions of the pancreas are either pseudocysts or neoplasms. Pseudocysts follow acute pancreatitis or trauma, when liquefied necrotic tissue and enzyme-rich fluid are walled off by granulation tissue and fibrosis without an epithelial lining. True congenital cysts are lined by epithelium and arise from anomalous duct development; multiple cysts occur in autosomal dominant polycystic kidney disease, von Hippel-Lindau disease and cystic fibrosis.
Structure
- Pseudocyst: single cavity, often next to the pancreas in the lesser sac; wall of fibrous and granulation tissue with hemosiderin and macrophages, no epithelium.
- Congenital cyst: unilocular thin-walled cyst with serous fluid and an epithelial lining.
Step by step
- Acute pancreatitis or trauma causes necrosis of pancreatic and peripancreatic tissue.
- Necrotic tissue liquefies and enzyme-rich fluid collects.
- Granulation tissue surrounds the collection.
- Over weeks, fibrous tissue matures into a wall without epithelium.
- The cyst persists, resolves, or becomes infected or bleeds.
Pseudocyst vs congenital cyst
| Feature | Pseudocyst | Congenital cyst |
|---|---|---|
| Lining | None (fibrous and granulation tissue) | Epithelium |
| Origin | After pancreatitis or trauma | Developmental duct anomaly |
| Fluid | Enzyme-rich, turbid or bloody | Clear serous |
| Associations | Alcohol, gallstone pancreatitis | ADPKD, von Hippel-Lindau, cystic fibrosis |
Test yourself
Think of the answer, then tap the question to see it.
What feature makes a pancreatic pseudocyst a 'pseudo' cyst?
It has no epithelial lining; its wall is granulation and fibrous tissue.
What usually precedes a pancreatic pseudocyst?
An episode of acute pancreatitis (often alcoholic) or pancreatic trauma.
Which inherited diseases cause true pancreatic cysts?
Autosomal dominant polycystic kidney disease, von Hippel-Lindau disease and cystic fibrosis.
Connections
Educational content on the mechanisms of disease; not a diagnostic or treatment guide and no substitute for a health professional's advice. No doses are given.
Sources: Pancreatic pseudocyst: MedlinePlus Medical Encyclopedia (MedlinePlus, US National Library of Medicine, 2026).
Spotted a mistake?We are always improving for the community. Tell us what is wrong and our team will review it.Report a mistake
Representative model, for educational purposes only.