Pancreas
Exocrine tumors / carcinomas
Intraductal papillary mucinous neoplasm (IPMN)

Author: Diana Agostini-Vulaj D.O.
Editor: Raul S. Gonzalez, M.D.

Revised: 1 August 2018, last major update July 2018

Copyright: (c) 2002-2018, PathologyOutlines.com, Inc.

PubMed Search: Intraductal papillary mucinous neoplasm[TI] pancreas[TI] free full text[sb]

Cite this page: Agostini-Vulaj, D. Intraductal papillary mucinous neoplasm (IPMN). PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/pancreasipmn.html. Accessed August 15th, 2018.
Definition / general
Essential features
  • Grossly visible (> 1 cm) cystic pancreatic neoplasm usually in head of pancreas
  • > 90% 5 year survival with complete resection
  • Roughly 1/3 of cases have an associated invasive carcinoma
  • Further subtyped into gastric, intestinal and pancreatobiliary types based on epithelium (note: intraductal oncocytic papillary neoplasm (IOPN) is now considered a distinct and separate entity)
Terminology
  • Low grade to intermediate grade dysplasia previously termed: intraductal papillary mucinous adenoma
  • High grade dysplasia previously termed: intraductal papillary mucinous carcinoma, noninvasive
  • With an associated invasive carcinoma previously termed: intraductal papillary mucinous carcinoma, invasive
  • Other previous terms include: mucin producing tumor, mucinous duct ectasia, ductectatic mucinous cystadenoma / cystadenocarcinoma, villous adenoma or papillary adenoma / carcinoma (Bosman: WHO Classification of Tumours of the Digestive System, 4th Edition, 2010)
ICD-10 coding
  • D13.6: benign neoplasm of pancreas
Epidemiology
Sites
  • Main duct IPMN mostly involves head of pancreas, 1/3 in body, 1/3 in tail (Hum Pathol 2012;43:1)
  • Branch duct IPMN mostly involves head of pancreas or uncinate process, with multiple distinct lesions seen in ~1/3 of cases (Hum Pathol 2012;43:1)
Etiology
Diagrams / tables

Images hosted on PathOut server:

AFIP

Four prototypes of IPMN



Images hosted on other servers:

Proposed neoplastic pathways

Clinical features
Diagnosis
  • Radiographic / endoscopic findings
  • Surgical specimen
Laboratory
Radiology description
  • CT:
    • Main duct IPMN causes distention of main pancreatic duct
    • Branch duct IPMN produces multilocular grape-like cystic appearance
  • ERCP: pancreatic ductal filling defects may be seen / ductal dilation
  • MRCP: additional imaging option which does not produce radiation
  • EUS: can also allow FNA and cyst fluid analysis
Prognostic factors
  • Without an invasive carcinoma has > 90% 5 year survival; those associated with an invasive carcinoma carry a worse prognosis (about half die of disease) (Ann Surg 2016;263:162)
  • Main duct IPMN: 60% have high grade dysplasia and 45% are associated with an invasive carcinoma (Hum Pathol 2012;43:1)
  • Branch duct IPMN: most are low grade, 25% have high grade dysplasia and 20% are associated with an invasive carcinoma (Hum Pathol 2012;43:1)
  • Invasive carcinoma associated with IPMN includes:
    • Tubular (ductal) adenocarcinoma: seen in about half of cases, with slightly better prognosis than non IPMN associated pancreatic ductal adenocarcinoma
    • Colloid carcinoma: seen in half of cases, with much better prognosis than pancreatic ductal adenocarcinoma (Ann Surg 2016;263:162)
Treatment
  • Main duct IPMN: surgical resection for all cases
  • Branch duct IPMN: indications for resection include symptomatic, association with mural nodule, dilated main duct and positive cytology (if size > 3 cm without any of the prior characteristics, can be observed) (Pancreatology 2012;12:183)
Gross description
Gross images

Images hosted on PathOut server:

Contributed by
Dennis R. Dening, PA (ASCP)CM

Main duct IPMN



 AFIP

Main duct involvement: left sided pancreatectomy specimen

Sticky mucin



Images hosted on other servers:

Branch duct
involvement (arrows
in figure on right are
main pancreatic duct)

Main duct involvement

Microscopic (histologic) description
Microscopic (histologic) images

Images hosted on PathOut server:

Contributed by Diana Agostini-Vulaj D.O.

IPNM intestinal 20x

IPMN gastric at 40x

IPMN gastric at 100x

MUC1

MUC2



AFIP

Branch duct

Epithelial papillary proliferations

Low grade dysplasia

Intermediate grade dysplasia:
lining epithelium of papillae is
characterized by nuclear enlargement,
stratification and crowding

High grade dysplasia and invasion (left)

  

High grade dysplasia:
cells have varying sized
nuclei, some show thick
nucleoli and mitoses (arrow)


High grade dysplasia:
severely atypical epithelium
forms irregular projections
without any tissue stalk

High grade dysplasia:
the atypical epithelium
shows branching and
bridging

Tall columnar mucin producing epithelium

PAS

CEA



Images hosted on other servers:

Gastric papillae

       

Gastric papillae top: low grade (blue arrows)
and intermediate grade dysplasia (black arrows);
bottom: high grade dysplasia (black arrows) with
cribriform formation and marked nuclear atypia

Comparison of subtypes:
gastric, intestinal,
pancreaticobiliary,
oncocytic

Intestinal papillae

Intestinal papillae (H&E and CDX2+)


   

Intestinal papillae:
intermediate grade
dysplasia (top) and
high grade dysplasia (bottom)

Invasive (colloid carcinoma, figure 9)

Noninvasive (figure 4)

  

Pancreaticobiliary papillae:
intermediate grade dysplasia
(top) and high grade
dysplasia (bottom)


Patient with both gastric and intestinal papillae

Loss of mismatch repair in patient with Lynch syndrome

Positive stains
Negative stains
Molecular / cytogenetics description
Differential diagnosis
Board review question #1
Which subtype of IPMN is more likely to arise from a branched pancreatic duct?

  1. Gastric
  2. Intestinal
  3. Pancreatobiliary
  4. Invasive
Board review answer #1
A.
Board review question #2
Based on the below clinical scenario which would most likely represent an IPMN?

  1. 29 year old woman with 8 cm solid and cystic pancreatic tail mass
  2. 45 year old woman with 3 cm cystic pancreatic tail mass
  3. 58 year old man with 3 cm solid pancreatic head mass
  4. 66 year old man with 2 cm cystic pancreatic head mass
  5. None of the above
Board review answer #2
D. 66 year old man with 2 cm cystic pancreatic head mass