Multiple schwannomas synchronously occurring in the porta hepatis, liver, and gallbladder: first case report

Background: Schwannomas are mesenchymal neoplasms that arise from Schwann cells with low malignant potential. Schwannomas originating from the porta hepatis or intra-abdominal organs are extremely rare. To our knowledge, multiple schwannomas synchronously occurring in the porta hepatis, liver, and gallbladder have not been reported so far and we first report one in the present case. Case summary: A 31-year-old female was referred to our hospital because of repeated abdomen discomfort, slight abdominal distension, and occasional abdominal pain for seven years. Ultrasound and computed tomography and magnetic resonance cholangiopancreatography found multiple intrahepatic and extrahepatic cystic lesions with the dilation of intrahepatic and extrahepatic bile ducts. By exploratory laparotomy, multiple tumors were found in the porta hepatis, liver, and gallbladder, the biggest one was 11 x 6 cm in size. We completely resected these tumors combined with the left lateral liver lobe, gallbladder, and the invaded left and right hepatic arteries, and then severed vessels were reconstructed. Microscopically, the tumor cells were spindle shaped and palisading arrangement. Atypical cells or signs of malignancy were not found. Immunohistochemical investigation showed the protein S-100 was positive, while SMA, CD34, and CD117 negative. Finally, these tumors were diagnosed as schwannomas in the porta hepatis, liver, and gallbladder. The patient is followed-up for 70 months and has been doing well without any complications. Conclusion: We report the first patient with multiple schwannomas synchronously occurring in the porta hepatis, liver, and gallbladder. Accurate preoperative diagnosis of these tumors is difficult. Due to closely adhering to the surrounding important tissues, complete removal is challenging.