Liver Metastasis from Mixed Acinar-Endocrine Carcinoma of the Pancreas : A Case Report and Review of the Literature

Mixed acinar-endocrine carcinoma (MAEC) of the pancreas is an exceedingly rare tumor, and the clinicopathological and oncological behavior of this type of tumor is scarcely known. A 42-year-old male patient with MAEC and metachronous liver metastasis was referred to our hospital for the treatment of repeated pancreatitis. A computed tomography (CT) scan revealed a pancreatic tail mass 3x8cm in size with expansive growth into the main pancreatic duct. Endoscopic retrograde pancreatography showed a filling defect in the main pancreatic duct, and an endocrine tumor was suspected by cytology of the pancreatic juice. A distal pancreatectomy was performed, and the immunopathological diagnosis was MAEC of the pancreas. The patient received S-1 chemotherapy after the surgery. Two years later, dynamic CT showed 2 hyper vascular hepatic nodules, 14mm and 8mm in diameter, in segment 4 of the liver. Laparoscopic assisted partial hepatectomy was performed and histological findings were compatible with a metastatic MAEC. One year later, a 5-mm hepatic nodule was detected in segment 3 by magnetic resonance imaging. The hepatic tumor was resected by laparoscopic surgery and diagnosed as a metastatic MAEC. The patient is alive and disease-free 50months after the first operation.