the presentation is about benign and malignant cystic masses of pancreas , their diagnostic differentials and radiologic features.

1. Cystic masses of
pancreas
Dr sidra yonis
PGR radiology

2. Pancreatic Cystic lesions
• Are broadly classified as:
• Post inflammatory pseudocysts….most common
• Common cystic neoplasms: account for 90% of cystic neoplasms
• IPMN…Intraductal papillary mucinous neoplasm
• SCN…Serous cystic neoplasm
• MCN…Mucinous cystic neoplasm

3. Uncommon cystic neoplasms:
SPEN…. solid pseudopapillary epithelial neoplasm
Tumors with cystic degeneration : Adenocarcinoma , neuroendocrine
tumors , cystic islet tumors( insulinoma , glucagonoma),metastasis
True epithelial cysts……associated with VHL,ADPKD and cystic fibrosis

5. Pancreatic pseudocyst
• Most common cystic lesion of pancreas
• Develop after 4 weeks after acute pancreatitis if APFC don’t resolve
• Suspect pseudocysts when there is history of acute pancreatitis , alcohol
abuse , stone disease or abdominal trauma

6. Radiographic features
• Ultrasound:
• Hypoechoic or anechoic collections with dependent low-level echoes,
representing debris

7. Pancreatic pseudocyst

8. • CT:
• Pseudocysts appear as well-circumscribed, usually round or oval
peripancreatic fluid collections of homogeneously low attenuation , usually
surrounded by well defined enhancing wall.

9. CT:

10. • MRI:
T1
Hypointense(fluid signal) center
Wall demonstrates mild early enhancement , progressively becoming intense
T2
Hyperintense(fluid signal)
Layering debris , highly specific

11. T1 sequence

12. MRI features:

14. Serous cystadenoma/Microcystic adenoma
• Benign microcystic lobulated neoplasm composed of innumerable 1-20 mm sized
small honeycomb cysts , separated by thin connective tissue septa.
• Highly vascular tumor
• Accounts for app. 50% of all cystic pancreatic neoplasms.
• Mostly seen in elderly women with mean age of 65yrs(grandma lesion)
• Can affect any part of pancreas with slight predominance for pancreatic head and
neck.
• Associated with VHL syndrome

15. Radiographic features
• USG:
 US features of microcystic adenoma of the pancreas include more than six small (<2-cm) cysts, a
central stellate scar, and calcifications.
Appear as non-specific mass having hypo and hyperechoic areas
Or as predominantly solid echogenic mass

16. Transverse US image shows a mass in the
pancreatic head (arrow) containing numerous
small cysts (arrowheads).

18. Serous cystadenoma
• CT scan:
• typically appears as a multi cystic, lobulated mass in the pancreatic head giving
appearance of 'bunch of grapes'
• the individual cysts are typically <20 mm in size and greater than six in number
• a characteristic enhancing central scar may be present which can show associated
stellate calcification
• May appear solid mass , showing hyper vascular enhancement
• There is no communication between cysts and pancreatic duct

22. Serous cystadenoma
• MRI:
• T1: typically hypointense
• T2: Cluster of small hyperintense cysts , and central fibrous scar if present
appears hypointense with delayed post-contrast enhancement of scar
• If signal void seen in central scar…calcification
• T1+contrast: delayed enhancement of septa

23. T2WI sequence
Lesion is multi-cystic
Central low signal area , represents
scar with calcification

24. T2WI demonstrates a lobulated
hyperintense lesion with central scar,
which is characteristic of a SCN

25. Mucinous cystadenoma/Macrocystic
adenoma
• Accounts for 10% cases of pancreatic cystic neoplasms
• Thick-walled uni /multilocular low grade malignant tumor
• Commonly seen in middle aged women , mean age 47yrs(mother lesion)
• Often seen in pancreatic tail and body, rarely in head
• Composed of multi/unilocular large cysts >2 cm and number of cysts usually less
than 6
• Hypo vascular mass
• Amorphous discontinuous peripheral calcification seen in 10-15% of cases

26. Radiographic features
• USG:
A large well-defined cyst containing turbid
contents(low level echoes), likely arising from
the tail of the pancreas , seen in the epigastric
region

27. Mucinous cystadenoma
• CT Scan:
• Appear as rounded or ovoid pancreatic mass with associated peripheral
calcification
• mucinous contents of the lesion may be heterogenous in attenuation
• internal septations may be seen

28. CT-images of a 32 year-old
female
Shows a large cyst in the
pancreatic tail with peripheral
calcification

29. CT images of a 30 year old
female shows
A non-lobulated cystic lesion in the pancreatic
tail with internal enhancing septation

30. Mucinous cystadenoma
• MRI:
Unilocular / mildly septated cystic lesion of homogenous T1 hypo intensity
and T2 hyperintensity
• Thick mildly enhancing septa
• Typically there is no
Communication with pancreatic duct
Or enhancing soft tissue component

31. TIWI post contrast image shows a
large hypointense cystic lesion in
pancreatic tail with mildly
enhancing internal septa

32. Axial T2WI Sequence shows
hyperintense encapsulated
unilocular pancreatic tail mass

33. Intra-ductal papillary tumors
• Are epithelial pancreatic cystic tumors of mucin-producing cells arising from
pancreatic duct.
• Most frequently identified in older patients,50-60yrs age referred as
“grandfather lesion”.
• Clinically , difficult to distinguish it from chronic pancreatitis . Patients present
with weight loss , obstructive jaundice , and recurrent pancreatitis.

34. IPMN…cont:
• Macroscopically , divided into:
• Main duct type: shows segmental or diffuse distribution , with highest
malignant potential.
• Branch duct type: mostly seen in the head and uncinate process, with
indolent behavior.
• Mixed type lesions

36. Radiographic features
• Most reliable diagnostic finding, communication between cystic lesion and
main pancreatic duct.(Best appreciated on MRCP)
• USG:
• Appear as small thin walled pancreatic cyst or dilated pancreatic duct.
• Diffuse main duct type appears indistinguishable from chronic pancreatitis ,
with duct dilatation and parenchymal atrophy.
• Mural nodule may appear hyper echoic within dilated duct.

37. CT Scan findings:
• Appear as single or multiple pancreatic cysts.
• Main pancreatic duct dilated >5mm
• Communication of mass with pancreatic duct may be difficult to
demonstrate on CT.

38. CT-images of an IPMN with a dilated pancreatic duct (blue arrows).
Note enhancing solid nodule in the pancreatic head (red arrow).

39. MRI features:
• Has largely replaced CT on imaging workup of these lesions
• Main duct IPMN: main pancreatic duct dilated more than 5mm.
• Either segment or entire pancreatic duct is dilated and filled with T1 hypo
and T2 hyper-intense material.
• Dilatation of major/minor papilla bulging into duodenal lumen.
• Pancreatic parenchymal atrophy may be noted.

40. • Signs of malignancy are:
• Pancreatic duct > 8 mm
• Solid nodule in duct , particularly if enhancning
• Mass around the pancreatic duct

41. Branch type IPMN
• Mainly seen in uncinate process>pancreatic tail
• Radiographic features include: dilatation of single or multiple side
branches. Main pancreatic duct may or may not be dilated.
• May have micro or macro-cystic appearance
• Micro-cystic variety has appearances similar to serous cystadenomas , but
communication with pancreatic duct is the diagnostic key.

45. On MRCP the cystic nature is better appreciated
and there is a connection to a widened duct (blue
arrow).

46. In a 73 year old male a hypoechoic lesion was found in the
pancreatic body, that looked like a cystic lesion.
CT also identifies the lesion but isn't of much help.

47. The heavily T2WI nicely
demonstrates the multicystic
lesion with the connection to the
pancreatic duct.
This was diagnosed as a branch-
duct IPMN

50. UNCOMMON NEOPLASMS
• Solid pseudo-papillary neoplasms:
• Rare and usually benign slow growing low grade tumor.
• Many tumors are completely solid and cystic components are secondary to
tumor degeneration
• Seen in young women in 2nd and 3rd decades of life(daughter tumor)
• Greater predilection for pancreatic tail

51. Radiographic features:
• Ultrasound: large well-defined mass with heterogeneous appearance due to
solid and cystic component.
• CT: appear as well-encapsulated lesion with varying solid and cystic
components.
• Enhancing solid areas are typically noted peripherally with cystic spaces seen
centrally.

52. CT-images of a 26 year old woman with a large mass in the
pancreatic head and metastases in the liver.
In the center there is lack of enhancement due to cystic or
necrotic degeneration.

53. MRI:
• Appear as well-defined lesion , with pure solid consistency seen in 80% of
cases.
• Hypo-intense fibrous capsule on T1W1 and T2WI(80-90%)
• Solid component : appears iso to hypo intense on T1WI as compared to
pancreas, and mildly hyper-intense on T2WI.
• High signal intensity foci on T1WI…represent hemoglobin degradation
products from internal hemorrhage(distinctive feature)

54. T2WI shows a well-encapsulated ovoid
hyper-intense mass arising from tail of
pancreas .

55. Axial T1 C+ with fat sat showing
enhancing solid mass with non-
enhancing cystic components.

56. Neuroendocrine tumors with cystic
degeneration
CT-image of a neuroendocrine tumor with
central necrosis.
Notice the peripheral enhancement.