Extrapancreatic solid pseudopapillary neoplasm: report of a unique case of primary posterior mediastinum origin and review of the literature

Solid pseudopapillary neoplasm (SPN) is an uncommon and low grade malignant tumor that traditionally occurs in pancreas. SPN accounts for 0.3% to 2.7% of all pancreatic exocrine tumors (1). SPNs have been seen in men and women aged 2 to 85 years but are most frequently associated with younger women aged 20 to 30 years, with a slight predilection for the pancreatic head and tail (2,3). Extrapancreatic SPN is extremely rare. The first extrapancreatic SPN was reported by Ishikawa et al. in 1990 (4). To our knowledge, only approximately 50 cases of extrapancreatic SPNs have been reported so far in the English literature (5). Testis/paratesticular area and ovary are the most common location of extrapancreatic SPN (6,7), followed by retroperitoneum, mesentery, omentum, and so on. SPN in mediastinum has not been reported in the literature. Herein, we report an additional extrapancreatic SPN in a 62-year-old woman, and this is the first case of mediastinal SPN