Table 2.

Differential diagnosis of IPMN.

	Intraductal papillary mucinous neoplasm	Mucinous cystic neoplasm	Retention cyst	Simple mucinous cyst
Demographics	More common in elderly men (7th–8th decade of life)	More common in women (5th decade)	F = M Any age	F = M Any age
Location	Often head of the pancreas (>80%)	Tail or body (>90%)	Anywhere in the pancreas	Anywhere in the pancreas
Imaging	Dilated main pancreatic duct or multilocular cyst Mural nodules may correspond to invasive carcinoma or high-grade dysplasia	Multilocular or unilocular thick-walled cyst No connection with the main pancreatic duct	Unilocular cyst	Unilocular cyst
Histology	Papillary projections With low-grade or high-grade dysplasia	No connection with the main duct Contain ovarian-type stroma (ER+, PR+)	Downstream obstruction Lined by flattened epithelium, and lack papillary projections	No obstructive process No papillary projections No ovarian-type stroma
Molecular	KRAS GNAS TP53/PIK3CA/PTEN RNF43 BRAF KLF4 P16/CDKN2A SMAD4 TGFBR2	KRAS SMAD4 TP53	No specific mutations	KRAS KMT2C BRAF RNF43 CDKN2A SMAD4 TP53
Cyst fluid analysis	Elevated CEA levels (of >200 ng/ml) High amylase level	Elevated CEA Low amylase	Variable CEA or amylase	Variable CEA or amylase