Acinar cell carcinoma of the pancreas differs from ductal adenocarcinoma in several ways. Which serum tumour marker is characteristically elevated in acinar cell carcinoma but NOT in pancreatic ductal adenocarcinoma, and is associated with a specific paraneoplastic syndrome?

• A CA 19-9; associated with biliary obstruction
• B Lipase; associated with subcutaneous fat necrosis and polyarthritis (lipase hypersecretion syndrome) ✓
• C CEA; associated with mucinous differentiation
• D Alpha-fetoprotein; associated with hepatoid differentiation in acinar carcinoma

Explanation

Acinar cell carcinoma of the pancreas can secrete large quantities of lipase and other exocrine enzymes directly into the circulation, causing the lipase hypersecretion syndrome: subcutaneous fat necrosis (tender erythematous nodules), polyarthritis, and peripheral blood eosinophilia. Serum lipase is markedly elevated. This is pathognomonic for acinar cell carcinoma and does not occur in ductal adenocarcinoma (which does not retain secretory exocrine function). CA 19-9 is the marker for ductal adenocarcinoma.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.