Diagnostic Ultrasound - Abdomen and Pelvis

Mucinous Cystic Pancreatic Tumor
Diagnoses: Pancreas
TERMINOLOGY
• Synonyms: Mucinous cystic neoplasm, macrocystic
cystadenoma/carcinoma, mucinous
cystadenoma/carcinoma
IMAGING
• US: Not modality of choice: Difficult to visualize entire
pancreas due to overlying bowel or fat
○ Nonspecific hypovascular cystic mass
○ Cyst contents may be anechoic, echogenic with debris or
septations, ± solid component
• Contrast enhanced CT or MR used to accurately
characterize morphology and guide treatment
○ Solitary, uni- or multilocular cystic lesion in body or tail of
the pancreas
○ Typically fewer than 6 cystic components, which are each
> 2 cm in size
○ May contain peripheral calcification
○ No communication with pancreatic duct
KEY FACTS
• Endoscopic ultrasound (EUS): Invasive technique reserved
for when FNA is being considered
TOP DIFFERENTIAL DIAGNOSES
• Pseudocyst
• Intraductal papillary mucinous neoplasm
• Macrocystic variant of serous cystadenoma
• Solid pseudopapillary tumor
• Cystic pancreatic neuroendocrine tumor
CLINICAL ISSUES
• Seen almost exclusively in middle-aged women; termed
"mother lesion"
• Excellent prognosis without invasive carcinoma
• Worse prognosis when invasive carcinoma is present;
however better than with typical ductal-type
adenocarcinoma (75% vs. 5%)
(Left) Graphic shows a
multiseptated, cystic mass
in the tail of the pancreas.
Note that the pancreatic duct
ſt is displaced but not
obstructed. (Right) Transverse
oblique transabdominal
ultrasound shows a welldefined
cystic lesion arising
from the posterior body of the
pancreas with a thin
internal septation ſt and
posterior acoustic
enhancement st.
(Left) Transverse
transabdominal ultrasound
shows a well-defined, complex
cystic pancreatic mass
(calipers) with thick internal
septations ſt. (Right) Axial
CECT of the same lesion,
shows an encapsulated,
complex cystic mass with
internal septations ſt and
peripheral calcification st.
Note the few, relatively larger
cysts and unusual location in
the head of the pancreas.
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