The Role of Histopathology and Immunohistochemistry in the Diagnosis of Neuroendocrine Biliary Duct Tumor.
Neuroendocrine tumors of the biliary tract are rare entities developed form Kulchitsky cells which undergo a process of malignant transformation. However, the differential diagnostic between neuroendocrine tumors of the biliary tract and hilar cholangiocarcinoma is very difficult to be established during the preoperative workup; therefore, most patients are submitted to surgery with radical intent and the final diagnostic remains to be confirmed through histopathological and immunohistochemistry studies of the specimen of resection. We present the case of a 60 year old patient who was submitted to en bloc extended right hepatectomy (including segment IV and caudate lobe) with extra hepatic biliary tree resection and left hepatic duct preservation, left cholangiojejunostomy (Roux-En-Y technique), celiac and common hepatic arteries lymphadenectomy and segmental portal vein resection with end-to-end anastomosis for a tumor of the biliary carrefour extended to the right biliary duct and invading the portal vein. The histopathological and immunohistochemistry studies confirmed the presence of a grade 1 neuroendocrine tumor, the staining being positive for Chromogranin A, Neuron-Specific Enolase (NSE) and Ki-67 (1% nuclear positive). At 24 months follow-up the patient is free of recurrent disease.