Fig. 3

Endoscopic ultrasound and histological analyses of specimen aspirated from the pancreatic tumor. A Endoscopic ultrasound image of a 7 mm-hypoechoic tumor of the pancreatic body. B Histological findings of specimen aspirated from the pancreatic tumor. Sections of the aspirated specimen were stained by hematoxylin and eosin as well as by chromogranin A, synaptophysin, insulin and Ki67 (Magnification × 400). Tumor cells were positive for chromogranin A and synaptophysin, which is typical of neuroendocrine tumors. The proliferation index, assessed by Ki67 immunostaining, was < 2.0%. Tumor cells were positive for insulin but not for glucagon, gastrin, or somatostatin (data not shown)