A case of preoperatively diagnosed intrapancreatic accessory spleen performed limited surgery for not being able to ruled out malignancy of cystic component

Incidental detection of pancreatic tumors has in recent years become more frequent owing to progress made in diagnostic imaging. We report a case of a preoperatively diagnosed intrapancreatic accessory spleen performed limited surgery for not being able to ruled out malignancy of cystic component. A 55-year-old woman with suspected appendicitis underwent computed tomography which detected a cystic lesion with a solid component 3cm in diameter at the pancreatic tail. We suspected the tumor to be an intrapancreatic accessory spleen because endoscopic ultrasonography showed identical image patterns for both the solid component of the tumor and spleen. Superparamagnetic iron oxide magnetic resonance imaging showed a decrease in signals, and 99mTc-Sn colloid scintigraphy indicated an uptake in both lesions. The patient was given a diagnosis of intrapancreatic accessory spleen, and informed that malignancy could not be ruled out completely upon which she requested surgery. The tumor at the pancreatic tail was soft, brownish, and 3cm in diameter, and spleen preserving pancreatic tail resection was performed confirming the diagnosis of intrapancreatic accessory spleen by intraoperative frozen section. The postoperative course was uneventful and she was discharged on postoperative day 16. To the best of our knowledge only 9 cases of preoperatively diagnosed intrapancreatic accessory spleen have been reported in the literature, and we therefore report this rare case.