In this study, serial sections of rat pancreatic tissue were examined using light and transmission electron microscopy to determine the epithelial cellular arrangement. One or more large-sized acinar cells with secretory canaliculi were discovered wedged into a small-sized intercalated duct cell line and connected with sequential acinar cells. These cells were shown to have direct contact with the outer surface of the intercalated duct without a basement membrane, forming secretory canaliculi branching from an intercalated ductal lumen along with the intercalated duct cells. Most islets of Langerhans lacked portions of peripheral basement membranes, thus allowing acinar cells or intercalated duct cells to have direct contact with endocrine cells in the peripheral islets. This resulted in formation of secretory canaliculi or intercalated ducts along with those endocrine cells. Based on these findings, it is speculated that differentiated endocrine or acinar cells wedged into peripheral portions of immature pancreatic duct cell lines individually proliferate out of the pancreatic ducts, with adjacent clusters of endocrine cells merged into an islet, after which the proliferating acinar cells along with secretory canaliculi establish direct contact with the outer surfaces of pancreatic ducts and islets.

【Background】It is important for general practitioners to be able to find pancreatic cancers of ≤1cm from abdominal ultrasound and risk factors. 【Objective】Here we report the results of an awareness survey on pancreatic cancer. 【Methods】Questionnaires were distributed to 1,465 members of the Kanagawa Physicians Association, and 126 people responded (age M=61.6 y). 【Results】Ninety-one percent of facilities were equipped with ultrasound machines, and there was high awareness of predictive signs of pancreatic cancer based on ultrasonography and high-risk factors. Physicians specializing in gastroenterology were significantly (P < 0.05) superior to others regarding expert knowledge of normal diameter and ability to visualize the main pancreatic duct of an ultrasonography. While imaging tests were performed at the time of exacerbation, there was a significant tendency for tests not to be performed on patients with diabetes at the time of the first visit (P < 0.05), despite it being a high-risk factor. 【Conclusion】To support early detection of pancreatic cancer, physicians should be more proactive with imaging tests for patients with diabetes.

After undergoing prolactin-producing pituitary adenoma removal surgery at age 9, a 34-year-old female was diagnosed with adult growth hormone deficiency and began hormone replacement therapy. Four months later, abdominal CT showed an incidental cystic lesion 50mm in diameter in the pancreatic tail. In addition to hypergastrinemia and hyperglucagonemia, the patient had mildly elevated intact PTH. Somatostatin receptor scintigraphy revealed high levels of accumulation in the lesion. Although pancreatic neuroendocrine tumor (pNET) was suspected, a definitive diagnosis by EUS-FNA was difficult because the lesion was predominantly cystic. Based on ultrasound endoscopy, the preoperative diagnosis was mucinous cystic tumor followed by laparoscopic resection of the pancreatic body tail tumor. Because gastrin-producing tumors were observed in areas other than the thickened wall and limbs of the cyst, the patient was diagnosed with MEN1 presenting with pNET. Differential diagnosis of pancreatic tumors with cysts is difficult and requires multiple viewpoints. A large number of cases of pNET should be accumulated to build up evidence for postoperative adjuvant treatment.

A male in his 60s aware of an abdominal mass for 14 years but asymptomatic had not visited a medical institution. During a medical checkup, he was informed of his mass and admitted. Imaging revealed an upper abdomen 26-cm tumor with a mixture of cystic and substantial portions. A mixed-type pancreatic serous cystic neoplasm (SCN) was suspected; however, surgery was contraindicated due to common hepatic arterial penetration and varicose veins around the tumor. Regular follow-up was scheduled, but the patient experienced repeated bleeding from gastric varices six years later. Edoscopic hemostasis was ineffective. After a definitive SCN diagnosis by percutaneous tumor biopsy, the patient underwent endovascular treatment for hepatopatal gastric varices with abundant tumor blood flow. The left gastric vein was punctured under ultrasonographic guidance, and there was improvement following N-butyl-2-cyanoacrylate injection into embolized gastric varices. This is the first case report of a patient with an inoperably large SCN requiring percutaneous embolization of varicose veins.

A 69-year-old man suffering from recurring epigastralgia for over 30 years presented to our department with epigastric pain. Contrast-enhanced computed tomography revealed acute pancreatitis, dorsal pancreatic duct dilation, aplasia of the pancreatic uncinate process, and intestinal malrotation. Magnetic resonance cholangiopancreatography revealed the pancreas divisum and showed the ventral pancreatic duct was located more cranial than the dorsal pancreatic duct, which we diagnosed as ventral pancreas malrotation. It is believed that this occurred during the development of the pancreas, when rotation of the ventral pancreas was hindered by intestinal malrotation and the ventral pancreas fused with the dorsal pancreas at the upper pancreatic head. Pancreatitis resolved without drainage of the dorsal pancreatic duct via the accessory papilla. The coexistence of ventral pancreas malrotation and pancreas divisum has not been previously reported, and findings were indicated by detailed image evaluations.