Neuroendocrine carcinoma in the extrahepatic biliary tract

Abstract

Rationale:Neuroendocrine carcinoma (NEC) arising from the extrahepatic biliary tracts (EHBTs) is rare, and thus its management and prognosis remain poorly clarified. We herein describe a case of NEC in the perihilar EHBTs, and review the literature, together with a comparison between NECs in the perihilar and distal EHBTs, to elucidate the management strategy and oncological outcome of this rare entity.Patient concerns:A 62-year-old Chinese male was admitted with complaints of painless jaundice. Imaging studies revealed a 2-cm mass in the hepatic hilum, regional lymph node involvement, and severe stenosis at the junction of the common hepatic ducts.Diagnoses:The histopathological examination of the resected specimen demonstrated small tumor cells with round hperchromatic nuclei and scant cytoplasm. A detailed immunohistochemical analysis showed that the tumor was strongly positive for synaptophysin, CD56 and chromogranin A, with a Ki-67 labeling index greater than 80%. These results led to a diagnosis of NEC in the perihilar bile duct.Interventions:The patient underwent surgical resection including a left hemihepatectomy, cholecystectomy, lymphadenectomy and Roux-en-Y hepaticojejunostomy.Outcomes:During the two months of follow-up, repeated imaging studies indicated tumor recurrence in the liver. The patient died 6 months after surgery.Lessons:NEC in the EHBTs is extremely challenging to diagnose preoperatively because of mimicking other bile duct cancers. The prognosis of this disease entity is dismal, and most patients die within 2 years after diagnosis. Subtyping of NECs into perihilar NECs and distal NECs is beneficial for clinical applications, including guiding therapy selection and predicting survival.

Rapidly progressed neuroendocrine carcinoma in the extrahepatic bile duct: a case report and review of the literature

“…Another possible reason is that cytology specimens stained with Papanicolaou and biopsy specimens stained with Hematoxylin-Eosin (HE) alone may have a high false negative rate for diagnosing NEC [3]. Immunohistochemical staining is usually required for a definitive diagnosis of NEC, but pathologists do not always conduct this unless NEC is suspected.…”

“…We searched the PubMed database using the terms “neuroendocrine carcinoma,” “bile duct,” “endocrine carcinoma,” and “mixed adeno-neuroendocrine carcinoma.” Excluding NECs in the intrahepatic bile duct, gallbladder, and ampulla of Vater, only 24 resected cases of primary EHBD NECs were found [ 3 , 10 – 32 ]. We briefly summarized these clinical and pathological features (Tables 1 and 2 ).…”

“…The most common primary site of digestive system was the small intestine (1.05 per 100,000 persons), followed by the rectum (1.04 per 100,000 persons) and the pancreas (0.84 per 100,000 persons) [2]. Only 0.32% of NENs occur in the extrahepatic bile duct (EHBD), and almost all of them are well-differentiated neuroendocrine tumors (NETs) [3]. Poorly differentiated neuroendocrine carcinomas (NECs) of the EHBD are rare, reportedly accounting for only 0.19% of EHBD malignancies [4].…”

“…EHBD NEC is also known for being difficult to diagnose preoperatively [3]. Many reported cases were resected with a diagnosis of cholangiocarcinoma and then diagnosed as NEC after surgery.…”

Mixed adenoendocrine carcinoma in the extrahepatic biliary tract: A case report and literature review

“…Several attempts have been made to clarify the clinical settings of this unusual disease. However, prior studies only focused on a single pathological type (mainly NET or NEC) (8–10). Additionally, currently, the prognostic factors of NEN in the EHBT have not been investigated (11).…”