Solid pseudopapillary tumour

A rare type of pancreatic tumor

Solid pseudopapillary tumour (SPT), also known as solid pseudopapillary neoplasm (SPN), is a rare type of pancreatic neoplasm that primarily affects young women. It is characterized by its low malignant potential and distinctive histological features.

Epidemiology

SPT accounts for approximately 1-2% of all pancreatic tumors. It predominantly occurs in young females, with a mean age of diagnosis around 30 years. Although rare, it can also occur in males and older individuals.

Relative incidence of pancreatic neoplasms

Pathophysiology

The exact pathogenesis of SPT is not well understood. However, it is believed to arise from the pancreatic ductal epithelium. Genetic studies have shown mutations in the CTNNB1 gene, which encodes for beta-catenin, a protein involved in the Wnt signaling pathway.

Histopathology

SPT is characterized by a combination of solid and pseudopapillary patterns. The tumor cells are typically arranged around blood vessels, forming pseudopapillae. The presence of these pseudopapillae is a hallmark of the tumor.

Histopathology of solid pseudopapillary tumor

Papillae vs pseudopapillae

Cytopathology

On cytological examination, SPT shows a mixture of solid and cystic areas. The cells are usually uniform with eosinophilic cytoplasm and round to oval nuclei. Nuclear grooves and intranuclear cytoplasmic inclusions may be present.

Cytopathology of solid pseudopapillary neoplasm

Immunohistochemistry

SPT typically shows positive staining for beta-catenin, vimentin, and CD10. The nuclear accumulation of beta-catenin is a characteristic finding.

Beta-catenin immunohistochemistry in solid pseudopapillary tumor

Clinical Presentation

Patients with SPT often present with non-specific symptoms such as abdominal pain or a palpable abdominal mass. Due to its indolent nature, the tumor may grow to a large size before detection.

Diagnosis

Diagnosis of SPT is typically made through imaging studies such as CT scan or MRI, followed by histological examination of a biopsy or surgical specimen.

Treatment

The primary treatment for SPT is surgical resection. Due to its low malignant potential, complete surgical removal often results in a good prognosis. Recurrence is rare but can occur.

Prognosis

The prognosis for patients with SPT is generally favorable, with a high survival rate following complete surgical resection. Malignant transformation and metastasis are uncommon.

Related pages

• Pancreatic cancer
• Pancreatic cysts
• Neoplasm