Pancreatic neuroendocrine neoplasms coexisting with biliary intraductal papillary mucinous neoplasm: A case report and review of literature

BACKGROUND Pancreatic neuroendocrine neoplasms (pNENs) are rare, heterogeneous tumors accounting for 1%-2% of pancreatic tumors, with significant malignant potential. Intraductal papillary mucinous neoplasm of the bile duct (IPMN-B) is a rare precancerous lesion in the bile duct system, with potential for malignancy. The combination of pNENs and IPMN-B is exceptionally rare and often leads to misdiagnosis. This study aims to report a rare case of pNENs combined with IPMN-B treated at Yanbian University Hospital to improve understanding and management of this unusual tumor combination. CASE SUMMARY We retrospectively analyzed a case from Yanbian University Hospital. We reviewed clinical records, imaging findings, endoscopic retrograde cholangiopancreatography, surgical exploration, and histopathological examination. The patient was diagnosed with pNENs and IPMN-B. Surgical treatment was performed, with follow-up showing effective management and no significant recurrence. CONCLUSION This case represents the first report of pNENs combined with IPMN-B. It highlights the need for thorough diagnostic evaluation to prevent misdiagnosis and improve treatment strategies.