Summary

Solid pseudopapillary neoplasms (SPNs) of the pancreas are rare tumors arising from pancreatic tissue, predominantly affecting young women and possessing low malignant potential. Extrapancreatic SPNs are exceedingly uncommon. According to data from the English literature, only 30 cases of extrapancreatic SPNs had been reported by 1990, accounting for less than 1% of all reported SPNs from 2004 to 2018. The testis, paratesticular region, and ovary are the more frequently documented sites of these tumors [1,2]. Notably, to the best of our knowledge, no cases of SPN originating in the diaphragm have been reported in the English literature to date. The prevailing theory suggests that SPNs behave similarly regardless of whether they originate in the pancreas or in extrapancreatic locations.

We present the case of a 79-year-old female with a history of lung and endometrial cancer, who was diagnosed with a liver lesion during a routine follow-up ¹⁸F-fluorodeoxyglucose positron-emission tomography/computed tomography (¹⁸F-FDG PET/CT). During surgery, the lesion was resected from the diaphragm and was confirmed to be consistent with the pathological findings of SPN.