This document summarizes a radiology department meeting discussing the imaging and management of pancreatic cystic lesions. It provides an overview of different types of cystic pancreatic lesions including pseudocysts, serous cystadenomas, mucinous cystic neoplasms, and intraductal papillary mucinous neoplasms (IPMN). For each type, the document describes key imaging features, pathology, and clinical management considerations. Endoscopic ultrasound is also discussed as a useful adjunct for evaluating cystic lesions through aspiration and sampling. The document concludes with recommendations on follow-up imaging intervals and pearls to help differentiate different cystic pancreatic lesions based on factors like age, gender, location, presence of calcification, and duct

1. Imaging of Pancreatic
Cystic Lesions
John Murray MD, Bruce Stewart MD
& Alvin Yamamoto MD
NSMC Radiology Department Meeting
February 4, 2009

2. Outline
1. BS: Overview & Approach to Cystic
Pancreatic Lesions
2. JM: Intraductal Papillary Mucinous
Neoplasms (IPMN)
3. AY: NSMC Cases

3. Introduction
 Increasingly incidentally detected
 More than 1/3 asymptomatic
 Imaging important for determining
prognosis and management
 CT>MR generally preferred for
characterization except for IPMN
 Simple classification for approach to DDx
 DDx discussed here account for 90% lesions
 Role of Endoscopic US

4. Cystic Pancreatic lesions: A Simple
Imaging-based Classification System for
Guiding Management
Sahani DV, Kadavigere R, Saokar A,
Fernandez-del Castillo C, Brugge WR, Hahn PF.
Radiographics 2005 Nov-Dec;25(6):1471-84.

5. Classification of Cystic Pancreatic
Lesions
 Pseudocyst
 Common cystic pancreatic neoplasms
 Serous cystadenoma
 Mucinous cystic neoplasm
 IPMN
 Rare cystic pancreatic neoplasms
 Solid pseudopapillary tumor
 Acinar cell cystadenocarcinoma
 Lymphangioma
 Hemangioma
 Paraganglioma

6. Classification of Cystic Pancreatic
Lesions (cont)
 Solid pancreatic lesions with cystic degeneration
 Pancreatic adenocarcinoma
 Cystic islet cell tumor (insulinoma, glucagonoma,
gastrinoma)
 Metastasis
 Cystic teratoma
 Sarcoma
 True epithelial cysts*
*Associated with von Hippel–Lindau disease, autosomal
-dominant polycystic kidney disease, and cystic
fibrosis)

7. Four Morphologic Types of Cystic
Lesions of the Pancreas

8. Unilocular Cyst
 Pseudocyst
 IPMN occasionally
 Unilocular serous cystadenoma
 Lymphoepithelial cyst
 Multiple
 von Hippel-Lindau
 Pseudocysts

9. Pseudocyst
 Generally symptomatic (i.e. pain)
 If asymptomatic, think about another Dx
 History of acute or chronic pancreatitis
 Almost always pseudocyst with this history
 Look for associated findings
 Pancreatic inflammation, parenchymal calcifications,
atrophy, typical intraductal calcifications
 Can communicate with pancreatic duct
 Wide neck vs. narrow neck for IPMN
 Wall can calcify
 No mural nodules

10. Pseudocyst

11. Pseudocyst in a patient with a
recent history of pancreatitis

12. Side-branch IPMN manifesting as a
unilocular cyst

13. Multiple unilocular cysts in a patient with
von Hippel–Lindau disease

14. Microcystic Lesions
 Serous cystadenoma
 Only lesion included in this category
 Benign tumor
 “Grandmother Lesion”
 May grow up to approx 4 mm/year
 70% cases demonstrate:
 Polycystic/microcystic pattern
 Collection of cysts (>6)
 Range: few mm – 2 cm
 External lobulations
 Enhancing septa, walls
 30% demonstrate fibrous central scar +/- stellate calcifcation
 Other variants (macrocystic + oligocystic)

15. Serous cystadenoma in 2 patients

16. Serous cystadenoma
(macrocystic variant)

17. Macrocystic Lesions
 Mucinous cystic neoplasms
 Intraductal Papillary Mucinous Neoplasm
(IPMN)

18. Mucinous cystic neoplasms
 Mucinous cystadenomas & cystadenocarcinomas
 Multilocular with complex internal architecture
 May contain internal hemorrhage or debris
 Peripheral eggshell Ca++ predictive of malignancy
 Body & tail of pancreas
 Asymptomatic in 75% cases
 If symptoms, usually due to mass effect
 “Mother Lesion”
 High potential for malignancy
 Surgical resection yields good prognosis

19. Mucinous cystadenoma
manifesting as a multiseptated cyst

20. Mucinous cystadenocarcinoma

21. Mucinous cystic tumor

22. Mucinous cystadenoma

23. IPMN
Pathology: Borderline IPMN w/o in situ or invasive carcinoma
Radiographics 2005; 25:1451-1470

24. Endoscopic US
 Can provide detailed morphologic evaluation of cystic
lesions
 For detecting malignant tumors:
 Sensitivity: 40%
 Specificity: 100%
 Accuracy: 50%
 Advantage of aspiration of contents, sampling of cyst
wall, septa or mural nodule
 Less potential for tumor seeding than percutaneous sampling
 Highly viscous contents (mucin) consistent with mucinous
neoplasm
 Tumor markers, cytologic analysis, biochemical markers, fluid
amylase
 At NSMC, performed by Drs. Jeff Oringer & Khoa Do

25. Cysts with a solid component
 Unilocular or multilocular
 True cystic tumors or solid pancreatic neoplasms with
cystic component/degeneration
 Wide DDx
 Mucinous cystic neoplasms
 IPMNs
 Islet cell tumor
 Solid pseudopapillary tumor (SPEN)
 Adenocarcinoma
 Metastasis
 All malignant or have a high malignant potential
 Surgical management

26. Islet cell tumor manifesting as a
cyst with a solid component

27. Solid pseudopapillary tumor
manifesting as a cyst with a solid
component

28. Metastases manifesting as cysts with
solid components
Pancreatic Adenocarcinoma Malignant IPMN

29. Management

30. Follow-up
 No consensus
 6 month intervals for 1st year
 Annual imaging for 3 years

31. Pearls
 Age & Gender
 “Daughter Lesion”: SPEN
 “Mother Lesion”: Mucinous cystic
 “Grandmother Lesion”: Serous cystadenoma
 Location
 Head/neck for serous & side branch IMPN
 Body/tail for mucinous cystic neoplasm
 Calcification
 Peripheral in mucinous cystic
 Central in serous cystadenoma
 Mural Nodularity (enhancement = neoplasm)
 Duct communication (narrow neck) favors IPMN
From Stat Dx: Cystic Pancreatic Mass & Seminars in US, CT & MRI 2007; 28: 3389-356