A case of mixed adeno-neuroendocrine carcinoma with liver metastasis of neuroendocrine tumor component after adjuvant chemotherapy: a case report and literature review

Abstract

We report a rare case of pancreatic cancer, mixed adeno-neuroendocrine carcinoma. A 47-year-old man was admitted to our hospital because of jaundice. Abdominal enhanced computed tomography showed an unclear demarcated mass 36mm in the head of the pancreas. ERCP showed a stenosis in main pancreatic duct and distal bile duct. On FDG/PET-CT, the tumor showed high SUVmax=3.9. With a diagnosis of pancreatic carcinoma, the patient underwent a pylorus preserving pancreatoduodenectomy. Histological and immunohistochemical examinations revealed that the tumor consisted of ductal component and neuroendocrine component. By these findings, the tumor was diagnosed as mixed ductal-neuroendocrine carcinoma. The patient received biweekly gemcitabine and S-1 chemotherapy for 20 months as adjuvant chemotherapy. Twenty-one months after the surgery, CT revealed multiple liver metastases. The patient received gemcitabine and S-1 chemotherapy for metastatic disease. Thirty months after the surgery, the patient underwent liver biopsy. Histological and immunohistochemical examinations of the liver specimen showed that the tumor consisted of neuroendocrine tumor without ductal carcinoma component. The patient was treated with 10mg of everolimus orally as a treatment for the neuroendocrine tumor. Seven years and 3 months after the surgery, the patient is still undergoing treatment.