Solid Pseudopapillary Neoplasm of the Pancreas with High-Grade Malignant Transformation Involving p16-RB Pathway Alterations

Abstract

Solid pseudopapillary neoplasm (SPN) of the pancreas has generally been regarded as a low-grade malignant tumour that preferentially develops in young women and can have a good prognosis with surgery. Among the few patients who have died from metastatic SPN are mostly those whose tumours harbour an undifferentiated component characterized by diffuse sheets of cells with increased nuclear atypia and proliferative index. We herein report a case of an aggressive, fatal, solid pseudopapillary neoplasm (SPN) of the pancreas in a 63-year-old woman complaining of epigastric pain. Despite having undergone surgical resection for a 10 cm pancreatic mass and multiple liver metastases, the patient later died due to uncontrollable metastases 36 months after the initial surgery. Histological examination showed that the tumour displayed unusual high-grade malignant features, showing diffuse sheets of cells with increased nuclear atypia and proliferative activity, along with conventional low-grade malignant features. The tumour was subsequently recognized as an SPN with foci of high-grade malignant transformation according to the 2010 World Health Organization classification. Immunohistochemical studies revealed that p16-RB pathway alterations contributed to the high-grade malignant transformation. The present case report suggests the necessity for developing diagnostic and treatment methods targeting p16 and RB for high-grade variants of SPN.

Pancreatic solid pseudopapillary neoplasm with concomitant left unilateral renal agenesis and bicornuate uterus: a case report

“…Among the few patients who die from metastatic SPN are mostly those whose tumors harbor an undifferentiated component that lacks pseudopapillary structures characterized by diffuse sheets of cells with increased nuclear atypia and proliferative index. These foci of high-grade malignant transformation are described as one histological subtype, SPN, with high-grade carcinoma in the latest edition 3 , 13 . Procedures such as distal pancreatectomy and splenectomy, spleen-preserving distal pancreatectomy, central pancreatectomy, pancreaticoduodenectomy, pylorus-preserving pancreaticoduodenectomy, and total pancreatectomy are the most common surgical procedures 8 .…”

Synchronous solid pseudopapillary neoplasm of the pancreas with intrahepatic cholangiocarcinoma in a young male patient: An unusual deadly occurrence

“…The clinical features associated with poor prognosis or malignancy include older age at presentation, males and tumour metastasis at the first operation. The histopathological features include perineural and angioinvasion, high mitotic rate, spindling of tumour cells, anaplastic giant cells, capsular invasion and necrosis [ 2 , [8] , [9] , [10] ].…”

SMARCB1/INI1-deficient pancreatic undifferentiated rhabdoid carcinoma mimicking solid pseudopapillary neoplasm: A case report and review of the literature

“…The tumor cells usually have a moderate amount of eosinophilic cytoplasm with perinuclear vacuoles, relatively uniform nuclei with finely textured chromatin, inconspicuous nucleoli and longitudinal grooves, and often containing intracytoplasmic hyaline globules. High-grade malignant transformation of SPN with an aggressive clinical course has been reported[ 20 - 23 ]. The morphological features predicting high-grade transformation include diffuse growth pattern, extensive tumor necrosis, significant nuclear atypia, high mitotic rate and presence of an undifferentiated component[ 20 ], while typical histologic architecture and cytological features of a SPN are always present.…”