A 41-year-old man with an 8 mm-sized nodule in the pancreatic head revealed by abdominal ultrasonography was referred to our hospital for further examination. To make a pathological diagnosis, we firstly performed an EUS-FNA. However, we couldn't obtain sufficient specimens to diagnose pathologically. Seven months later, we performed an EUS-FNB for the nodule and the histopathological findings showed spindle-shaped tumor cells proliferating in bundles. With immunostaining, the specimen was negative for c-kit, CD34, and desmin but positive for S-100 protein. Based on these findings above, the lesion was diagnosed as a pancreatic schwannoma. Therefore, we decided to follow up the patient with careful observation rather than surgical resection of the lesion. Pancreatic schwannoma is difficult to diagnose preoperatively because of the lack of imaging characteristics. However, adequate pathological diagnosis using biopsy specimen provide crucial information for clinical decision. Therefore, EUS-FNB is considered to be useful modality for the diagnosis of pancreatic tumor.
