A Rare Case of the Coexistence of Pancreaticobiliary Maljunction and Gastrointestinal Tumor in Neurofibromatosis Type 1

Neurofibromatosis type 1 (NF1) is a congenital condition characterized by "café au lait" spots and subcutaneous fibromas. There are various combined diseases, such as malignant tumors in the abdominal organs or brain tumors. Here, we present a case of a 35-year-old patient with a rare combination of NF1 with a gastrointestinal stromal tumor (GIST) and pancreaticobiliary maljunction (PBM). At the first visit, her main symptom was right upper abdominal pain. Radiological investigations revealed a common bile duct stone, submucosal tumor in the duodenum, PBM, and abnormal findings in the intrahepatic bile ducts. After the common bile duct stone was removed by endoscopic intervention, the patient underwent laparoscopic cholecystectomy, resection of the duodenal submucosal tumor, and liver biopsy. Pathological examination revealed chronic cholecystitis, GIST of the duodenum, and chronic inflammation of the intrahepatic bile ducts. This is the first case report of the rare coexistence of GIST and PBM in a patient with NF1.