Background: Long non-coding ribonucleic acid (lncRNA) ELFN1 antisense RNA 1 (ELFN1-AS1) is involved in the pathogenesis of many different cancers. But the current research on the relationship between lncRNA ELFN1-AS1 and pancreatic cancer is still blank. Methods:We investigated the role of lncRNA ELFN1-AS1 in the pathogenesis of pancreatic cancer using bioinformatics, in vitro and in vivo experiments in pancreatic cancer cell lines, and surgically removed clinical samples.Results: Through bio-information analysis and in vitro and in vivo experiments, we found that LncRNA ELFN1-AS1 was highly enriched in pancreatic cancer data sets and highly expressed in pancreatic cancer cell lines and tissues. The knocking down of lncRNA ELFN1-AS1 significantly increased cancer cell death and growth arrest. Xenografts in nude mice showed that the growth of SW1990 cells in the mice group with a stable knock down of lncRNA ELFN1-AS1 was significantly slower than that in the control group. Conclusions:The experimental results show that the expression of LncRNA ELFN1-AS1 is related to the growth and invasion ability of pancreatic cancer cells. By further studying the function of LncRNA ELFN1-AS1 in pancreatic cancer, LncRNA ELFN1-AS1 was found to be involved in the epithelial-mesenchymal transition process in pancreatic cancer.

We have newly defined a type of pancreatitis based on clinical practice experience, namely pancreatic tumorassociated pancreatitis (PTP). PTP has many new features in terms of diagnosis and treatment, and it is therefore necessary to describe it in detail.AP has various causes and a complex pathogenesis, and its occurrence and development are affected by many factors.

Inflammatory myofibroblastic tumor (IMT) is a rare disease of unknown etiology. It usually occurs in abdominal soft tissues and lung, and is extremely rare in the pancreas. IMT can occur in any part of a person at any age, however, it mostly affects children and young people. Its clinical manifestations are atypical, imaging examinations are not specific, and the differential diagnosis of pancreatic malignancies is difficult, making it easily misdiagnosed. Surgical resection is the preferred method of treatment for IMT. In this case report, we report a rare case of IMT in the neck of the pancreas and reviewed the relevant literature.In our case, the patient was a 57-year-old woman with an IMT in the neck of the pancreas. Abdominal pain was the only clinical symptom, and imaging features were not specific. She underwent surgery to remove the pancreatic mass, and the final diagnosis of IMT was based on histopathology and immunohistochemistry.After 6 months of regular follow-up, the patient had no complications or further incidents. The purpose is to emphasize the difficulty of the preoperative diagnosis of pancreatic IMT and the difficulty of distinguishing it from pancreatic malignancies. It is hoped that clinicians can gain a deeper understanding of pancreatic IMT through this case report.

Objective: Although considerable progress has been made in our understanding of intraductal papillary mucinous neoplasm (IPMN) of the pancreas, there are still some problems to be solved.Background: IPMN is one of the most important precancerous lesions of pancreatic cancer, but the relationship between IPMN and pancreatic cancer, and the specific mechanism of the development from IPMN to invasive carcinoma, remain to be explored in depth. With the development of imaging, the detection rate of IPMN has been greatly improved. However, the degree of malignancy of IPMN is difficult to assess, and its classification criteria and surgical treatment strategies are still controversial. Therefore, there is an urgent need for the best treatment plan for IPMN and research that can better predict IPMN recurrence and tumor malignancy.Methods: From the online database Web of Science (https://webofknowledge.com/) and PubMed (https:// pubmed.ncbi.nlm.nih.gov/), we use specific retrieval strategies to retrieve relevant articles based on the topics we discussed, and we review and discuss them.Conclusions: This paper discusses the related research and progress of IPMN in recent years to improve the understanding of the incidence, diagnosis, treatment, and prognosis of this disease. The follow-up and monitoring of IPMN is particularly important, but the specific strategy also remains controversial.

We report an extremely rare case of primary gastric melanoma with pancreatic metastasis. As far as we know, the concept of primary gastrointestinal melanoma is currently controversial, because there are very few reports of primary gastrointestinal melanoma. At the same time, isolated pancreatic metastases are also very rare. The patient was admitted to the hospital with a main complaint of decreased appetite, and then underwent gastroscopy and found a mass in the stomach. The mass was initially diagnosed as poorly differentiated adenocarcinoma following a gastroscopic biopsy. The patient underwent radical total gastrectomy, pancreatic body and tail resection, splenectomy, and Roux-en-Y esophagojejunostomy. After further immunohistochemical examination of the surgically removed tissue, malignant melanoma was diagnosed. The tumor cells were arranged in sheets or nests with infiltrating growth, the cell sizes were inconsistent, nucleoli were obvious, and melanin particles were seen in the cytoplasm of some cells. The tumor cells were positive for MITF and S-100. Detailed systemic and imaging examinations did not find any other primary lesions. The patient denied any melanoma and skin lesion history. We believe this is a manifestation of primary gastric melanoma. We report this rare case of gastric melanoma with the aim of increasing clinicians' awareness of non-cutaneous melanoma and its treatment methods.