A 55-year-old woman is found to have a 2 cm cystic pancreatic lesion communicating with the main pancreatic duct on MRCP. Biopsy shows mucin-producing columnar epithelium with papillary projections. Fluid cytology shows high CEA (>192 ng/mL). This lesion, with significant malignant potential, is best classified as:

• A Serous cystadenoma
• B Solid pseudopapillary neoplasm
• C Intraductal papillary mucinous neoplasm (IPMN) ✓
• D Mucinous cystic neoplasm (MCN)

Explanation

IPMN is defined by intraductal mucin-producing neoplasia communicating with the pancreatic duct system, distinguishing it from MCN (which does not communicate with ducts and shows ovarian-type stroma). IPMNs have significant malignant potential: main duct IPMNs carry ~60-70% risk of malignancy, while branch duct IPMNs have lower but clinically significant risk. High cyst fluid CEA (>192 ng/mL) and amylase distinguish mucinous from serous lesions. Solid pseudopapillary neoplasm occurs mainly in young women and is a solid-cystic tumor.

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

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.