EUS-FNAB and somatostatin-receptor scintigraphy enabled diagnosis and detection of multiple metastatic sites in a patient with diffuse pancreatic enlargement: A case of pancreatic neuroendocrine tumor

Abstract

A 60-year old man was referred to our department after diffuse pancreatic enlargement was detected with computed tomography (CT) prior to surgery for bladder cancer. Autoimmune pancreatitis (AIP) was strongly suspected due to the findings of diffuse pancreatic enlargement and multiple narrowing in the pancreatic duct. However, histopathological diagnosis via endoscopic ultrasound-guided fine-needle aspiration biopsy (EUS-FNAB) identified a neuroendocrine tumor (NET, Ki-67 index 7%). Somatostatin-receptor scintigraphy, which was performed to find systemic metastases, showed diffuse uptake in the pancreas, as well as a hepatic metastatic lesion and numerous bone metastatic lesions that had not been detected on CT. Subsequent pathological reevaluation determined that the bladder tumor was also an NET. Accordingly, pancreatic NET and systemic multiple metastases were determined to be the final diagnosis.