Differentiation of benign and malignant solid pseudopapillary neoplasms of the pancreas

J Comput Assist Tomogr. 2009 Sep-Oct;33(5):689-94. doi: 10.1097/RCT.0b013e31818f2a74.


Objective: The aim of this study was to investigate differential imaging features between benign and malignant solid pseudopapillary neoplasms (SPN) of the pancreas on computed tomographic and magnetic resonance imagings.

Methods: Between January 2001 and January 2007, we identified 30 patients with confirmed SPN by surgery. The computed tomographic and magnetic resonance images were reviewed by 3 radiologists in consensus. Each tumor was analyzed for the following categories: location of tumor, tumor margin, proportion of solid component, morphology of capsule, growth pattern, calcification, and presence of upstream pancreatic ductal dilatation.

Results: Benign SPN usually had oval/round or smoothly lobulated margins, and malignant SPN more commonly had focal lobulated margins (P = 0.027). Presence of complete encapsulation was more frequently seen in benign SPN, whereas focal discontinuity of capsule was more commonly seen in malignant SPN (P = 0.005). There was no statistical difference between benign and malignant tumors in other imaging findings.

Conclusions: A focal lobulated margin and a focal discontinuity of the capsule may suggest malignant SPN, whereas a round or smoothly lobulated margin and a complete encapsulation were more commonly seen in benign SPN.

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Calcinosis / pathology
  • Carcinoma, Papillary / diagnosis*
  • Carcinoma, Papillary / pathology
  • Carcinoma, Papillary / secondary
  • Carcinoma, Papillary / surgery
  • Diagnosis, Differential
  • Female
  • Follow-Up Studies
  • Humans
  • Liver Neoplasms / secondary
  • Logistic Models
  • Lymphatic Metastasis
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Neoplasm Invasiveness / diagnosis
  • Pancreatectomy
  • Pancreatic Diseases / diagnosis
  • Pancreatic Diseases / pathology
  • Pancreatic Neoplasms / diagnosis*
  • Pancreatic Neoplasms / pathology
  • Pancreatic Neoplasms / surgery
  • Treatment Outcome
  • Young Adult