Abstract
A 62-year-old man who visited a neighboring hospital because of headache was referred to our hospital. A CT scan of the whole body revealed left chronic subdural hemangioma and tumorous lesions at the pancreas tail and the spleen. He was then referred to our department. Upper and lower gastrointestinal endoscopy showed no malignant findings. No tumor markers were elevated. The IL2R and IgG4 levels were elevated to 1,500 U/ml and 181.0 mg/dl, respectively. FDG-PET scan offered a suspicion of malignant lymphoma. The patient was thus admitted for the purpose of operation. Operative findings included a 6-cm splenic tumor and a 7-cm tumor at the pancreas tail, each of which had smooth surface and was white in color and hard. We performed associated resection of the pancreas body and tail and the spleen. After the operation he developed fistula of pancreas, but it was conservatively treated. He was discharged from the hospital on the 27th postoperative day. On histopathology, a possibility of malignant lymphoma was ruled out, and inflammatory pseudotumor was diagnosed. The elevated IgG4 level was normalized and neurotic symptoms subsided, suggesting the most likely diagnosis of IgG4-related autoimmune pancreatitis.
