Retrospective study on the background pancreas on endoscopic ultrasonography in pancreatic tumors

Pancreatic cancer is a malignant tumor with a poor prognosis, and the incidence rate of pancreatic cancer-related morbidity and the rate of mortality are increasing.Abdominal ultrasonography is recommended as a screening tool for pancreatic cancer.High echogenicity (brightness) of the pancreas has attracted attention in recent years.However, its significance is unknown.An association was found between strong echogenicity of the pancreas and lifestyle-related diseases.However, the background pancreatic parenchyma ("background pancreas") in pancreatic diseases has not been analyzed extensively with endoscopic ultrasonography (EUS) .For the early detection of pancreatic cancer, we EUS was used to analyze the background pancreas in cases of pancreatic ductal adenocarcinoma (PDAC) and intraductal papillary mucinous tumor (IPMN) .The association between the background pancreas and PDAC/IPMN and between the background pancreas and life history of the patients was investigated.The current study enrolled 42 patients with PDAC and 40 with IPMN who underwent EUS at Showa University Hospital from August 1, 2021, to July 31, 2023.To measure the pancreas-kidney brightness ratio, the echogenicity (brightness) of the background pancreas of the patients was compared using the ImageJ software.The association between the appearance of the background pancreas and patients healthrelated habits was analyzed.The background pancreas was relatively dim in patients with PDAC.However, it was relatively bright in patients with IPMN.Further, the brightness of the background pancreas of was correlated with body mass index, hemoglobin A1c level, and serum triglyceride level in patients with IPMN.In terms of EUS and histopathological findings, patients with IPMN presented with fat deposition.Further, patients with PDAC exhibited parenchymal atrophy and fibrosis in the background pancreas.Analyzing the background pancreas on EUS may identify an association between lifestyle-related diseases and the diagnosis of pancreatic tumors.