organ system benign neoplasm_____
gastrointestinal system disease__|
                                 gastrointestinal system benign neoplasm
                                  |__hepatobiliary benign neoplasm
                                      |__biliary tract benign neoplasm
                                      |   |__ampulla of Vater benign neoplasm(+)
                                      |   |__bile duct adenoma(+)
                                      |   |__bile duct cystadenoma(+)
                                      |   |__biliary papillomatosis(+)
                                      |   |__biliary tract intraductal papillary mucinous neoplasm
                                      |   |__common bile duct neoplasm
                                      |   |__extrahepatic bile duct leiomyoma
                                      |   |__extrahepatic bile duct lipoma
                                      |   |__gallbladder benign neoplasm(+)
                                      |__liver benign neoplasm
                                          |__hemangioma of liver
                                          |__hepatic angiomyolipoma
                                          |__hepatocellular adenoma(+)
                                          |__liver fibroma
                                          |__liver leiomyoma
                                          |__liver lipoma