Six weeks after severe acute biliary pancreatitis, a 42-year-old woman has a persistent 8 cm lesser sac collection. Aspirate shows amylase 15,000 U/L and CEA 3 ng/mL. The histological hallmark of the wall of this lesion is:
- A Granulation tissue and dense fibrosis without any epithelial lining ✓
- B A single layer of mucin-producing columnar epithelium with ovarian-type stroma
- C Stratified squamous epithelium overlying lymphoid tissue
- D Cuboidal epithelium with papillary fronds and ovarian-type stroma
Correct answer: A. Granulation tissue and dense fibrosis without any epithelial lining
Explanation
A pancreatic pseudocyst forms after 4 weeks when a walled-off collection of enzyme-rich fluid becomes enclosed by granulation tissue and fibrous collagen. It lacks any epithelial lining, which is the defining feature separating it from true cysts and all cystic neoplasms such as mucinous cystic neoplasm, whose columnar epithelium with ovarian-type stroma is option B. Very high fluid amylase reflects ongoing duct disruption communicating with the collection.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.