Solid pseudopapillary tumours of the pancreas: spectrum of imaging findings with histopathological correlation

Solid pseudopapillary tumour (SPT) is an uncommon cystic exocrine pancreatic neoplasm. The typical patient is a female in the third decade of life presenting with pain and/or palpable mass. Classic imaging characteristics include large size, mixed solid and cystic nature, encapsulation and haemorrhage. A pancreatic mass with these features in a young adult female should raise suspicion for an SPT. Although typically a non-aggressive neoplasm with surgery curative in most cases, SPT may exhibit more aggressive features such as local invasion, metastases or recurrence in up to 20% of cases.Solid papillary tumour (SPT) is an uncommon exocrine pancreatic neoplasm first described by Frantz [1]. It accounts for 6% of all exocrine pancreatic tumours in some series published since 2000 [2]. In our retrospective review, SPT represented 2.4% of all pancreatic specimens from 2000 to 10.The accepted nomenclature for this tumour has varied through the years, including solid and papillary epithelial neoplasm (SPEN), as well as solid and cystic papillary epithelial neoplasm, among others. After the World Health Organization (WHO) reclassification, SPT is now classified as an epithelial tumour under the “Borderline (Uncertain Malignant Potential)” subcategory. Pathologically, SPT is classified as a “rare cystic pancreatic neoplasm”.About 90% of cases involve females, with the mean age of patients being in their third decade of life. The most common presenting symptom is abdominal pain followed by upper abdominal mass. Mean tumour size is 6–8 cm, with the most common site being the pancreatic head (34–40%) or the pancreatic tail (24–36%). With the increased use of cross-sectional imaging, however, an increasing number of cases are being detected incidentally.