Imaging of Pancreatic Imaging of Pancreatic Cystic LesionsCystic Lesions

John Murray MD, Bruce Stewart MDJohn Murray MD, Bruce Stewart MD

& Alvin Yamamoto MD& Alvin Yamamoto MD

NSMC Radiology Department MeetingNSMC Radiology Department Meeting

February 4, 2009February 4, 2009

OutlineOutline

1.1. BS: Overview & Approach to Cystic BS: Overview & Approach to Cystic Pancreatic Lesions Pancreatic Lesions

2.2. JM: Intraductal Papillary Mucinous JM: Intraductal Papillary Mucinous Neoplasms (IPMN) Neoplasms (IPMN)

3.3. AY: NSMC CasesAY: NSMC Cases

IntroductionIntroduction

Increasingly incidentally detectedIncreasingly incidentally detectedMore than 1/3 asymptomaticMore than 1/3 asymptomatic

Imaging important for determining Imaging important for determining prognosis and managementprognosis and management

CT>MR generally preferred for CT>MR generally preferred for characterization except for IPMNcharacterization except for IPMN

Simple classification for approach to DDxSimple classification for approach to DDxDDx discussed here account for 90% lesionsDDx discussed here account for 90% lesions

Role of Endoscopic USRole of Endoscopic US

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.

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

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)

Four Morphologic Types of Cystic Lesions of the Pancreas

Unilocular CystUnilocular Cyst

PseudocystPseudocyst IPMN occasionallyIPMN occasionallyUnilocular serous cystadenomaUnilocular serous cystadenomaLymphoepithelial cystLymphoepithelial cystMultipleMultiple

von Hippel-Lindauvon Hippel-LindauPseudocystsPseudocysts

PseudocystPseudocyst Generally symptomatic (i.e. pain)Generally symptomatic (i.e. pain)

If asymptomatic, think about another DxIf asymptomatic, think about another Dx History of acute or chronic pancreatitisHistory of acute or chronic pancreatitis

Almost always pseudocyst with this historyAlmost always pseudocyst with this history Look for associated findingsLook for associated findings

Pancreatic inflammation, parenchymal calcifications, Pancreatic inflammation, parenchymal calcifications, atrophy, typical intraductal calcificationsatrophy, typical intraductal calcifications

Can communicate with pancreatic duct Can communicate with pancreatic duct Wide neck vs. narrow neck for IPMNWide neck vs. narrow neck for IPMN

Wall can calcifyWall can calcify No mural nodulesNo mural nodules

Pseudocyst

Pseudocyst in a patient with a recent history of pancreatitis

Side-branch IPMN manifesting as a unilocular cyst

Multiple unilocular cysts in a patient withvon Hippel–Lindau disease

Microcystic LesionsMicrocystic Lesions Serous cystadenomaSerous cystadenoma

Only lesion included in this categoryOnly lesion included in this category Benign tumorBenign tumor ““Grandmother Lesion”Grandmother Lesion” May grow up to approx 4 mm/yearMay grow up to approx 4 mm/year 70% cases demonstrate:70% cases demonstrate:

Polycystic/microcystic patternPolycystic/microcystic pattern Collection of cysts (>6)Collection of cysts (>6) Range: few mm – 2 cmRange: few mm – 2 cm External lobulationsExternal lobulations Enhancing septa, wallsEnhancing septa, walls

30% demonstrate fibrous central scar +/- stellate calcifcation30% demonstrate fibrous central scar +/- stellate calcifcation Other variants (macrocystic + oligocystic)Other variants (macrocystic + oligocystic)

Serous cystadenoma in 2 patients

Serous cystadenoma(macrocystic variant)

Macrocystic LesionsMacrocystic Lesions

Mucinous cystic neoplasmsMucinous cystic neoplasms Intraductal Papillary Mucinous Neoplasm Intraductal Papillary Mucinous Neoplasm

(IPMN)(IPMN)

Mucinous cystic neoplasmsMucinous cystic neoplasms

Mucinous cystadenomas & cystadenocarcinomasMucinous cystadenomas & cystadenocarcinomas Multilocular with complex internal architectureMultilocular with complex internal architecture

May contain internal hemorrhage or debrisMay contain internal hemorrhage or debris Peripheral eggshell Ca++ predictive of malignancyPeripheral eggshell Ca++ predictive of malignancy Body & tail of pancreasBody & tail of pancreas

Asymptomatic in 75% casesAsymptomatic in 75% cases If symptoms, usually due to mass effectIf symptoms, usually due to mass effect

““Mother Lesion”Mother Lesion” High potential for malignancyHigh potential for malignancy Surgical resection yields good prognosisSurgical resection yields good prognosis

Mucinous cystadenoma manifesting as a multiseptated cyst

Mucinous cystadenocarcinoma

Mucinous cystic tumor

Mucinous cystadenoma

IPMNIPMNPathology: Borderline IPMN w/o in situ or invasive carcinoma

Radiographics 2005; 25:1451-1470

Endoscopic USEndoscopic US Can provide detailed morphologic evaluation of cystic Can provide detailed morphologic evaluation of cystic

lesionslesions For detecting malignant tumors:For detecting malignant tumors:

Sensitivity: 40%Sensitivity: 40% Specificity: 100%Specificity: 100% Accuracy: 50%Accuracy: 50%

Advantage of aspiration of contents, sampling of cyst Advantage of aspiration of contents, sampling of cyst wall, septa or mural nodulewall, septa or mural nodule Less potential for tumor seeding than percutaneous samplingLess potential for tumor seeding than percutaneous sampling Highly viscous contents (mucin) consistent with mucinous Highly viscous contents (mucin) consistent with mucinous

neoplasmneoplasm Tumor markers, cytologic analysis, biochemical markers, fluid Tumor markers, cytologic analysis, biochemical markers, fluid

amylaseamylase At NSMC, performed by Drs. Jeff Oringer & Khoa Do At NSMC, performed by Drs. Jeff Oringer & Khoa Do

Cysts with a solid componentCysts with a solid component Unilocular or multilocularUnilocular or multilocular True cystic tumors or solid pancreatic neoplasms with True cystic tumors or solid pancreatic neoplasms with

cystic component/degenerationcystic component/degeneration Wide DDxWide DDx

Mucinous cystic neoplasmsMucinous cystic neoplasms IPMNsIPMNs Islet cell tumorIslet cell tumor Solid pseudopapillary tumor (SPEN)Solid pseudopapillary tumor (SPEN) AdenocarcinomaAdenocarcinoma MetastasisMetastasis

All malignant or have a high malignant potentialAll malignant or have a high malignant potential Surgical managementSurgical management

Islet cell tumor manifesting as a cyst with a solid component

Solid pseudopapillary tumor manifesting as a cyst with a solid

component

Metastases manifesting as cysts with solid components

Pancreatic Adenocarcinoma Malignant IPMN

ManagementManagement

Follow-upFollow-up

No consensusNo consensus6 month intervals for 1st year6 month intervals for 1st yearAnnual imaging for 3 yearsAnnual imaging for 3 years

PearlsPearls Age & GenderAge & Gender

““Daughter Lesion”: SPENDaughter Lesion”: SPEN ““Mother Lesion”: Mucinous cysticMother Lesion”: Mucinous cystic ““Grandmother Lesion”: Serous cystadenomaGrandmother Lesion”: Serous cystadenoma

LocationLocation Head/neck for serous & side branch IMPNHead/neck for serous & side branch IMPN Body/tail for mucinous cystic neoplasmBody/tail for mucinous cystic neoplasm

CalcificationCalcification Peripheral in mucinous cysticPeripheral in mucinous cystic Central in serous cystadenomaCentral in serous cystadenoma

Mural Nodularity (enhancement = neoplasm)Mural Nodularity (enhancement = neoplasm) Duct communication (narrow neck) favors IPMNDuct communication (narrow neck) favors IPMN

From Stat Dx: Cystic Pancreatic Mass & Seminars in US, CT & MRI 2007; 28: 3389-356