Solid pseudopapillary tumour

Signs and symptoms

Solid pseudopapillary tumours are often asymptomatic and are identified incidentally on imaging performed for unrelated reasons. Less often, they may cause abdominal pain. Solid pseudopapillary tumours tend to occur in women, and most often present in the third decade of life.

Diagnosis

The gold standard for diagnosing solid pseudopapillary tumour of the pancreas is cytopathology by endoscopic ultrasound (EUS) guided fine needle aspiration (FNA) of the lesion. After surgical excision, the tumor can undergo histopathology evaluation for cancer staging.

Gross morphology

Solid pseudopapillary tumours are typically round, well-demarcated, measuring 2–17 cm in diameter (average 8 cm), with solid and cystic areas with hemorrhage on cut sections.

Histomorphology

Solid pseudopapillary tumours consist of solid sheets of cells that are focally dyscohesive. The cells in the lesion usually have uniform nuclei with occasional nuclear grooves, eosinophilic or clear cytoplasm and PAS positive eosinophilic intracytoplasmic globules. Necrosis is usually present and, as cell death preferentially occurs distant from blood vessels, lead to the formation of pseudopapillae.

Immunohistochemistry

Solid pseudopapillary tumours show positive nuclear staining for beta catenin, as well as positive immunostaining for CD10, CD56, vimentin, alpha 1-antitrypsin, and neuron specific enolase; they are negative for chromogranin and pancreatic enzymes. File:Histopathology of solid pseudopapillary tumor.png|Histopathology of solid pseudopapillary tumor File:Solid pseudopapillary tumour - high mag.jpg|Histopathology of a solid pseudopapillary tumour. H&E stain. This case also shows the key feature of intracytoplasmic hyaline globules. File:Relative incidence of pancreatic neoplasms.png|Relative incidence of various pancreatic neoplasms, with solid pseudopapillary neoplasm annotated at center right. File:Beta-catenin immunohistochemistry in solid pseudopapillary tumor.jpg|β-catenin immunohistochemistry in solid pseudopapillary tumor, staining the nuclei in 98% of such cases. Cytoplasm is also staining in this case.

Management

In most cases, solid pseudopapillary tumours should be resected surgically, as there is a risk of malignancy (cancer).

References

References

1. (2014). "Cytological criteria of high-grade epithelial atypia in the cyst fluid of pancreatic intraductal papillary mucinous neoplasms.". Cancer Cytopathol.
2. (2006). "Solid pseudopapillary neoplasm of the pancreas: a single institution experience of 14 cases". HPB.
3. (May 2014). "Solid pseudopapillary tumor: a rare neoplasm of the pancreas". Gastroenterol Rep (Oxf)..
4. (2018). "The importance of endoscopic ultrasound fine-needle aspiration in the diagnosis of solid pseudopapillary tumor of the pancreas: two case reports". Journal of Medical Case Reports.
5. Fletcher CDM. (2007). "Diagnostic Histopathology of Tumors". Elsevier.
6. (November 2008). "Revision 2: an immunohistochemical approach and evaluation of solid pseudopapillary tumour of the pancreas". J. Clin. Pathol..
7. (March 1991). "Solid and cystic pancreatic tumors. Clinical, histochemical, and electron microscopic features in ten cases". Cancer.
8. (November 1992). "Papillary cystic tumor of the pancreas: A clinicopathologic study of 20 cases with cytologic, immunohistochemical, ultrastructural, and flow cytometric observations, and a review of the literature". [[American Journal of Clinical Pathology]].
9. Pooja Navale, M.D., Omid Savari, M.D., Joseph F. Tomashefski, Jr., M.D., Monika Vyas, M.D.. "Solid pseudopapillary neoplasm".
10. (2011). "Diffusion-weighted MR imaging of solid and cystic lesions of the pancreas.". Radiographics.
11. Pooja Navale, M.D., Omid Savari, M.D., Joseph F. Tomashefski, Jr., M.D., Monika Vyas, M.D.. "Solid pseudopapillary neoplasm".