We report a rare case of glucagonoma of the pancreas, in which intra-operative cytology was helpful. By histological examination of a frozen section, it was difficult to determine whether the tumor was endocrine tumor, acinar cell carcinoma, or invasive ductal carcinoma. Cytologically it was diagnosed as endocrine tumor from the cytological features of noncohensive clusters, scanty, granular and rich cytoplasm, and round nuclei with even granular chromatin, there by excluding other malignant tumors.
