A 38-year-old male patient presented with a two-month history of abdominal discomfort associated with obstructive jaundice and asthenia over the past 20 days.
CT and cholangio-MRI showed a partially calcified 2 cm mass with intense contrast uptake dependent on the extrahepatic bile duct, causing retrograde dilatation of the proximal biliary tree without signs of local extension or distant extension.
Tumor markers (CEA, CA 19.9, AFP) were normal.
A block resection of the extrahepatic bile duct was performed with the mass, cholecystectomy and regional lymphadenectomy.
Preoperative examination of the surgical specimen suggested a neuroendocrine tumor (NET) of the common bile duct with free margins.
The postoperative course of the patient was satisfactory and she was discharged 6 days after surgery without complications.
The final pathology report showed a 2 cm tumor with a fibrous stroma in its central part with small and homogeneous cells organized in pseudo-acinar formations.
On the periphery, the tumor differentiated with large cells with abundant and clear cytoplasm, microvaccinated and rounded nucleus.
There was also perineural and lymphatic involvement.
The definitive diagnosis was neuroendocrine carcinoma with high expression of CD56 and CK7, chromogranin and moderate expression synaptophysin, and with a Ki67 index of 15% (G2), without lymph node involvement.
