Diagnostic Ultrasound - Abdomen and Pelvis

Solid Pseudopapillary Neoplasm
Diagnoses: Pancreas
TERMINOLOGY
• Epithelial tumor of exocrine pancreas with low-grade
malignant potential and solid and cystic features
IMAGING
• Large, well-demarcated mass with solid and heterogeneous
cystic areas due to hemorrhage and necrosis; typically in
pancreatic tail
• US: Heterogeneous mass due to mixture of isoechoic soft
tissue and hypoechoic central necrosis/hemorrhage
• Best imaging tool: CT and MR for demonstrating
intratumoral hemorrhage and enhancing capsule/solid
components
TOP DIFFERENTIAL DIAGNOSES
• Mucinous cystic pancreatic tumor
• Pancreatic neuroendocrine tumor
• Pancreatic serous cystadenoma
• Pancreatic ductal carcinoma
KEY FACTS
PATHOLOGY
• Fibrous, hypervascular capsule with solid and
pseudopapillary tissue surrounding hemorrhagic and
necrotic center
• Low malignant potential
CLINICAL ISSUES
• Very rare, < 3% of all pancreatic tumors
• Typically in asymptomatic, young, non-Caucasian women;
termed "daughter lesion"
• Excellent prognosis after surgical excision
• < 10% metastasize or recur
DIAGNOSTIC CHECKLIST
• Consider diagnosis if encapsulated pancreatic tail mass with
solid, cystic, and hemorrhagic components is found in
young non-Caucasian female and there is no pancreatic
ductal dilation
(Left) Graphic shows a large
encapsulated mass in the
pancreatic tail with solid ſt
and cystic or hemorrhagic
components. (Right)
Transverse transabdominal
ultrasound demonstrates a
large, well-defined,
heterogeneous cystic mass ſt
in the pancreatic tail.
(Courtesy A. Kamaya, MD.)
(Left) Axial CECT
demonstrates an
encapsulated, complex cystic
mass in the pancreatic tail
with enhancing peripheral
components ſt. (Courtesy A.
Kamaya, MD.) (Right)
Intraoperative US shows a
mass with peripheral soft
tissue ſt surrounding a
complex cystic center with
internal echoes reflecting
hemorrhage and necrosis.
(Courtesy A. Kamaya, MD.)
388