Abstract

A solid pseudopapillary tumour (also known as solid pseudopapillary neoplasm or, more formally, solid pseudopapillary tumour/neoplasm of the pancreas) is a low-grade malignant neoplasm of the pancreas of architecture that typically afflicts young women.

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.