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Transcript of Pancreatic cystic lesion by xiu
MR Imaging ofMR Imaging of Cystic Lesion of the PancreasCystic Lesion of the Pancreas
Present by : Ekksit Srithammasit, MDPresent by : Ekksit Srithammasit, MD
Kalb et al : Departments of Radiology , Surgery, and Pathology, Emory University School of Medicine, Atlanta.
2009;
IntroductionIntroduction
Pancreatic cystPancreatic cyst A common incidental finding in
cross-sectional imaging. Neoplastic VS Nonneoplastic
processes. Require surgical intervention VS
follow-up.
IntroductionIntroduction
The role of pancreatic cyst biopsy is debated.
Biopsy of a malignant fluid-containing lesion may lead to spread of malignant cells.
Histological analysis and chemical analysis produce a questionable diagnostic yield.
IntroductionIntroductionImaging detailed of pancreatic cyst : Cyst morphology Fluid content Communication with the pancreatic ductal
system. Entire pancreatic parenchyma
MRI = best suited for evaluating these features.MRI = best suited for evaluating these features.
Imaging ModalitiesImaging ModalitiesUltrasound
Lack of spatial resolution. Lack of soft-tissue
contrast resolution. Limited in large patients. Endoscopic US is
invasive.
Presence or absence of calcification : Presence or absence of calcification : notnot critical critical factor in the differentiation of pancreatic cyst.factor in the differentiation of pancreatic cyst.
CT Can depict small
pancreatic cysts. Limited to evaluated
internal septa of the cyst. Better demonstrated
Calcification.
Imaging ModalitiesImaging Modalities
MRI Good soft-tissue contrast. Clearer depiction of septa and other
cyst contents. Good to depiction of pancreatic ductal
system.
MRI = best suited for evaluating these features.MRI = best suited for evaluating these features.
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
MR Imaging TechniquesMR Imaging Techniques
T2W sequences.Fat saturation.MR cholangiopancreatography.
Dynamic 3D contrast enhanced T1W GRE sequences.
MR Imaging TechniquesMR Imaging Techniques
T2WI : coronal and axial planesT2WI : coronal and axial planes Cyst contents (fluid, septa) Pancreatic duct system.
Fat saturation. Allows the identification of acute
inflammatory changes. Improve depiction of the internal
architecture of a cyst.
MR Imaging TechniquesMR Imaging Techniques
MR cholangiopancreatography MR cholangiopancreatography (heavilyT2-weighted sequences)(heavilyT2-weighted sequences)Depiction of the ductal system Small communications between cystic
lesions and the pancreatic duct.
MR Imaging TechniquesMR Imaging TechniquesUnenhanced and contrastUnenhanced and contrast--enhanced T1-enhanced T1-
weighted imagesweighted images..
Enhancing soft-tissue components. The surrounding pancreatic parenchyma The pancreatic duct. Unenhanced T1WI:
Internal hemorrhage.Protein deposits.
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
PseudocystsPseudocysts
M/C cystic lesions of the pancreas.
Occur in the setting of pancreatitis: Hemorrhagic fat necrosis and encapsulation
by granulation tissue and a fibrous capsule.
PseudocystsPseudocysts
Irregularly marginated -> Well circumscribed, with a thickened.
Blood products and necrotic or proteinaceous debris. Intrinsically increased T1 signal intensity.
Acute or chronic pancreatitis.
PseudocystsPseudocysts Inflammation:
Increased SI surrounding a complicated pseudocyst on T2FS. Cause of inflammation is more likely to be chemical irritation than
infection Impossible to differentiate between an infectious process and
other possible causes on the basis of imaging features alone.
Dissect along abdominopelvic fascial planes to sites remote from the pancreas eg, liver, pleura, or mediastinum
Fistulation may occur between a pseudocyst and one or more vascular structures.
PseudocystsPseudocystsNo vascularized soft-tissue elements are present within
pseudocysts, and if vascularized elements are seen within a cystic lesion on contrast-enhanced MR
images, the lesion is not a pseudocyst.
PseudocystsPseudocysts
DDx with Mucinous cystadenomaDDx with Mucinous cystadenoma Mucinous cystadenomas often persist
without a significant interval change on F/U images.
Evidence of acute or chronic pancreatitis almost always found in pancreatic pseudocyst, not in mucinous cystadenoma.
Pancreatic pseudocyst.
(a) a simple fluid collection. (b) with chronic pancreatitis.
Pancreatic pseudocyst with F/U 2 months
(a) Complex cyst with a fluid-debris level (b) Resolution of the pseudocyst.
Pancreatic pseudocyst
Common findings in pancreatic pseudocysts: hemorrhage, protein deposition.
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
Serous CystadenomasSerous Cystadenomas
Benign cystic neoplasms Occur frequently in older women (median age,
65 years). Usually discovered incidentally. Large cyst may cause abdominal pain or,
more rarely, jaundice. Multiple serous cystadenomas may occur in
von Hippel–Lindau disease.
Serous CystadenomasSerous Cystadenomas Composed of numerous
small cysts: honeycomb like formation.
Size typically less than 1 cm ( 0.1-2 cm ).
Lined by glycogen-rich epithelium.
Fibrous septa that radiate from a central scar.
Central scar may be calcified.
Serous CystadenomasSerous Cystadenomas
MR imaging: MR imaging: Classic type - microcystic formClassic type - microcystic form A cluster of small cysts of simple fluid SI. No visible communication between the cysts and the
pancreatic duct. Delayed enhance of thin fibrous septa between small
cysts. Central scar : with or without coarse calcification. Progressive enlargement ≥ 4 cm may be seen at
serial follow-up over a period of months.
Serous CystadenomasSerous Cystadenomas
MR imaging: MR imaging: Less common types:Less common types:
Oligocystic variant: Oligocystic variant: Cysts are larger and
fewer. May mimic that of a
mucinous cystadenoma.
Solid variant: Solid variant: Composed of microscopic
serous cysts that too small to be reliably depicted on MR images.
MRI: solid, well-circumscribed, well-vascularized mass.
Features that overlap with those of pancreatic neuroendocrine tumors.
Cluster of many small cysts
Serous cystadenomas.
Calcified scar and enhancement of the internal septa
Serous cystadenomas.
Enhancement of the internal septa
Oligocystic serous cystadenoma.
Large cysts and lacks internal enhancing soft-tissue components.
Imaging features overlap with mucinous cystadenoma
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
•Mucinous Nonneoplastic Cysts.
•Mucinous Cystadenomas.
•Mucinous Cystadenocarcinoma.
•Pancreatic IPMNs.
Mucinous Nonneoplastic CystsMucinous Nonneoplastic Cysts
Nonneoplastic cysts. No neoplastic potential.
Mucin Containing Cyst
Mucinous differentiation of the epithelial lining cyst. No ductal communication. Lack the surrounding ovarian stroma . No cellular atypia, or the papillary projections.
Mucinous Nonneoplastic CystsMucinous Nonneoplastic Cysts
MRI FindingsMRI Findings Typically small and unilocular or thinly
septate. Internal SI of simple fluid. No enhancing soft-tissue components.
Mucin Containing Cyst
Mucinous Nonneoplastic CystsMucinous Nonneoplastic CystsMucin Containing Cyst
DDx with mucinous cystadenomas.
May be indistinguishable, especially if the cyst is
large and has a thick wall.
Mucinous cystadenomas
Mucinous Nonneoplastic Cysts
Mucin Containing Cyst
Mucinous nonneoplastic pancreatic cyst .
Bi-lobed, smoothly marginated cyst No enhancing soft-tissue elements.
Mucinous CystadenomasMucinous Cystadenomas
10% of pancreatic cystic neoplasms. Majority (>95%) found in women (mean
age, 47 years). Malignant potential cyst.
Mucin Containing Cyst
sampling of the cyst lining must be performed
Mucinous CystadenomasMucinous Cystadenomas
Typically involve body or tail of the pancreas.
Thickened walls, lined by mucin-producing columnar epithelium.
Presence of a surrounding ovarian-type stroma.
No communicate with the pancreatic ductal system.
Mucin Containing Cyst
Mucinous CystadenomasMucinous CystadenomasMRI FindingsMRI Findings Unilocular or mildly septate cystic lesion. Thicked and delayed enhanced wall. Contained fluid : typically mucin filled
More common - simple fluid SI Less common - Increased T1 SI
Often internal septal enhancement. Presence of internal enhancing soft tissue
elements is indicative of carcinoma.
Mucin Containing Cyst
Mucin Containing Cyst
Mucinous cystadenoma.
A single large lobulated cyst without internal enhancing soft-tissue elements.
Mucin Containing Cyst
Mucinous cystadenoma.
A rounded thick-walled cystic structure with thickened enhancing septa.
Mucinous CystadenocarcinomasMucinous Cystadenocarcinomas Older on average than those with diagnosis of
mucinous cystadenoma Progression from cystadenoma to
cystadenocarcinoma
Mucinus cyst with surrouding ovarian type stoma.
Invasive carcinomatous elements.
Mucin Containing Cyst
MRI Findings:MRI Findings: Large complex cysts. Intracystic enhancing soft tissue.
Mucinous CystadenocarcinomasMucinous CystadenocarcinomasMucin Containing Cyst
In a retrospective review of 163 resected In a retrospective review of 163 resected mucinous cysts with surrounding mucinous cysts with surrounding
ovarian-type stromaovarian-type stroma
17.5% of the cysts contained elements of invasive carcinoma at histologic analysis.
All of the lesions with an invasive carcinomatous component had a size of 4 cm or more and demonstrated soft-tissue nodularity.
Hence, any enhancing soft tissue within a cystic neoplasm depicted on MR images is considered an indication for resection.
Mucin Containing Cyst
Mucinous cystadenocarcinoma.
A large, complex cystic lesion with enhancing mural soft-tissue elements.
Pancreatic IPMNsPancreatic IPMNs Intraductal papillary mucinous neoplasms Most frequently in men (mean age, 65 years).
Noninvasive neoplasms with varying degrees of epithelial dysplasia.
Foci of carcinoma in situ. Frank invasive adenocarcinoma.
Mucin Containing Cyst
Pancreatic IPMNsPancreatic IPMNs Mucinous transformation of the pancreatic
ductal epithelium. Usually demonstrates papillary projections. Involves the main pancreatic duct or isolated
side branches. Main duct: 60%–70% invasive carcinoma Side branches: 22% foci of carcinoma.
Frequently multifocal, and 5%–10% involve the entire pancreas
Mucin Containing Cyst
Pancreatic IPMNsPancreatic IPMNsERCPERCP Excessive mucin production results in
cystic dilatation of the pancreatic duct. Possibly,spillage of mucin from the
ampulla of Vater : a classic finding at endoscopic retrograde cholangiopancreatography.
Mucin Containing Cyst
Pancreatic IPMNsPancreatic IPMNsMRI finding: MRI finding: Modality of choice Cyst with ductal communication. Main pancreatic duct dilatation or dilatation of
multiple side branches. Adenocarcinoma in association with an IPMN.
Enhancing soft-tissue nodularity Size more than 3.5 cm Thick walls.
Mucin Containing Cyst
Mucin Containing Cyst
IPMN with involvement of the main pancreatic duct. .
Diffuse dilatation of the main pancreatic duct with a focal cystic lesion.The lesion communicates with the distended main pancreatic duct.
Mucin Containing Cyst
IPMN with involvement of the side-branches.
Focal dilatation of ductal side-branches in the pancreatic head.
Mucin Containing Cyst
Invasive adenocarcinoma in association with an IPMN.
A complex cystic lesion with ductal communication and enhancing soft tissue component.
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
•Mucinous Nonneoplastic Cysts.
•Mucinous Cystadenomas.
•Mucinous Cystadenocarcinoma.
•Pancreatic IPMNs.
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
Lymphoepithelial CystsLymphoepithelial Cysts Rare benign pancreatic cysts. The imaging findings are not well described in
the literature. Most common: in men (mean age, 55 years)
The cysts are lined by squamous epithelium and surrounded by dense lymphoid tissue.
Their MR appearances vary: unilocular or multilocular.
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
Ductal adenocarcinoma with cystic features
Pseudopapillary tumors of the pancreas
Cystic neuroendocrine tumors
Ductal adenocarcinoma Ductal adenocarcinoma with cystic featureswith cystic features
The most common pancreatic neoplasms. (90%)
The most lethal tumor of the pancreas. (5-year survival of less than 3%).
Predominantly solid. 8% cyst like features:
cystic degeneration, retention cysts, and attached pseudocysts.
Solid Pancreatic Tumor with Cystic Degeneration
Ductal adenocarcinoma Ductal adenocarcinoma with cystic featureswith cystic features
Usually infiltrative growth pattern. Obstruction of the pancreatic duct or
CBD. Invasion of adjacent vasculature.
Solid Pancreatic Tumor with Cystic Degeneration
Ductal adenocarcinoma Ductal adenocarcinoma with cystic featureswith cystic features
MRI Findings:MRI Findings: Infiltrative soft-tissue lesion. Delayed enhancement (contrast material
gradually seeps into the tumor interstitium) Ductal obstruction. Complex cystic areas within or adjacent to the
primary soft-tissue lesion Pseudocysts, internal tumor necrosis, or side-
branch ductal obstruction.
Solid Pancreatic Tumor with Cystic Degeneration
Ductal adenocarcinoma Ductal adenocarcinoma with cystic featureswith cystic features
DDx Contain enhancing soft tissue and DDx Contain enhancing soft tissue and cystic components:cystic components:
Ductal Adenocarcinomas with Cystic Features. Infiltrative pattern of the primary tumor. Combined with ductal obstruction and vascular
invasion
Cystic neoplasms such as solid pseudopapillary tumor and mucinous cystadenocarcinoma.
Solid Pancreatic Tumor with Cystic Degeneration
Solid Pancreatic Tumor with Cystic Degeneration
Ductal adenocarcinoma with cystic changes.
A poorly vascularized infiltrative tumor with a central necrosis and pseudocyst.
Solid Pancreatic Tumor with Cystic Degeneration
Ductal adenocarcinoma with cystic changes.
A pancreatic tumor obstructed pancreatic and common bile duct with distention of the pancreatic duct side-branches.
Solid Pseudopapillary TumorsSolid Pseudopapillary Tumors Solid and cystic papillary epithelial neoplasm
of the pancreas. Papillary cystic neoplasm.
Uncommon lesions. Predominantly in women (mean age, 28
years). Low-grade malignant potential.
The cellular lineage remains uncertain: Epithelial VS neuroendocrine.
Solid Pancreatic Tumor with Cystic Degeneration
Solid Pseudopapillary TumorsSolid Pseudopapillary Tumors
MRI Findings:MRI Findings: Predominantly solid. Well circumscribed increased T2 signal
intensity. Gradual uniformly enhancing soft-tissue. Cystic components - secondary to tumor
degeneration. Hemorrhage - common
Solid Pancreatic Tumor with Cystic Degeneration
Solid Pseudopapillary TumorsSolid Pseudopapillary Tumors
DDx DDx Neuroendocrine tumor Mucinous
cystadenocarcinoma.
Solid Pancreatic Tumor with Cystic Degeneration
However, because all three entities require surgical
resection, their preoperative differentiation may not
be important in the clinical setting.
Solid pseudopapillary tumor of the pancreas.
A gradual enhancing solid tumor with internal hemorrhage.
Solid Pancreatic Tumor with Cystic Degeneration
Solid pseudopapillary tumor of the pancreas.
varying degrees of cysticdegeneration
Solid Pancreatic Tumor with Cystic Degeneration
Cystic Neuroendocrine TumorsCystic Neuroendocrine Tumors
Occur in adults (mean age, 53 years) without sex predilection.
Neuroendocrine tumors - Typically solid and well vascularized.
Cystic change - Uncommon.Secondary to tumor degeneration
Solid Pancreatic Tumor with Cystic Degeneration
Cystic Neuroendocrine TumorsCystic Neuroendocrine Tumors
Neoplastic neuroendocrine cells lining the cyst periphery
Solid Pancreatic Tumor with Cystic Degeneration
Cystic Neuroendocrine TumorsCystic Neuroendocrine Tumors
MRI Findings:MRI Findings: Well
circumscribed Avidly rim
enhacement in arterial phase.
Solid Pancreatic Tumor with Cystic Degeneration
A patient with a cystic neuroendocrine tumor is significantly
more likely tohave an underlying multiple
endocrine neoplasiasyndrome than a patient with a
uniformly solidneuroendocrine tumor.
Cystic neuroendocrine tumor.
A well define cyst with avidly enhancing thickening rim on arterial phase image.
Solid Pancreatic Tumor with Cystic Degeneration
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
Ductal adenocarcinoma with cystic features
Pseudopapillary tumors of the pancreas
Cystic neuroendocrine tumors
Table of ContentsTable of Contents MRI Technique Overview of lesions
PseudocystSerous CysadenomasMucin Containing CystLymphoepithelial CystSolid Pancreatic Tumor with Cystic
Degeneration
ConclusionsConclusions Common incidental finding in cross-
sectional imaging.
Neoplastic VS Nonneoplastic processes.
MRI is the best modality for evaluating pancreatic cyst.Good soft-tissue contrast and good to
depiction of pancreatic ductal system.
Which of the following modalities is optimal for depicting internal complexity of a pseudocyst?
A) MR imaging. B) Radiography. C) Multidetector CT. D) Endoscopic retrograde
cholangiopancreatography.
Which of the following cystic lesions of the pancreas is the most common overall?
A) Solid pseudopapillary tumor.B) Mucinous cystadenoma.C) Pseudocyst.D) Lymphoepithelial cyst.
Which of the following imaging methods best depicts vascularized soft tissue within a pancreatic cystic lesion?
A) Unenhanced and contrast-enhanced 3D MR imaging with T1-weighted sequences.
B) Axial thin-section 3D MR cholangiopancreatography.
C) Axial single-shot T2-weighted MR imaging. D) Coronal thick-slab MR
cholangiopancreatography.
Which of the following clinical or demographic characteristics is most common among patients with mucinous cystadenomas?
A) Presence of chronic or recurrent pancreatitis. B) Presence of von Hippel-Lindau disease. C) Age of less than 20 years. D) Female sex.
Which of the following pancreatic cystic lesions may occur in the setting of von Hippel-Lindau disease?
A) Mucinous cystadenoma.B) Serous cystadenoma.C) Ductal adenocarcinoma with cystic features.D) IPMN.
Which of the following characteristics of an IPMN is most commonly associated with invasive carcinoma?
A) Localization to a pancreatic duct side branch. B) Involvement of the main pancreatic duct. C) Absence of soft-tissue nodularity. D) Size of less than 3 cm.
Which of the following pancreatic cystic lesions does not include a vascularized soft-tissue component?
A) Mucinous cystadenocarcinoma. B) Solid pseudopapillary tumor. C) Mucinous nonneoplastic cyst of the pancreas. D) Ductal adenocarcinoma with cystic features.
Which of the following statements does not accurately characterize cystic pancreatic neuroendocrine tumors?
A) They are rarer than solid neuroendocrine tumors.B) They are more commonly associated with multiple endocrine neoplasia than are solid neuroendocrine tumors.C) They may include a vascularized soft-tissue component.D) They usually demonstrate poor margination and an infiltrative growth pattern.