Primary large cell neuroendocrine carcinoma of the common hepatic duct mimicking a Klatskin tumor

OUP accepted manuscript

Neuroendocrine carcinomas (NECs) arising from the extrahepatic bile duct (EHBD) are extremely rare, and their preoperative diagnosis is difficult. A small number of resected cases of EHBD NECs has been reported, and their prognosis is usually poor. A 62-year-old man presented with obstructive jaundice and liver disease. Radiological imaging revealed wall thickness and stricture of the distal common bile duct (CBD); however, lymph node or distant metastasis was not detected. Adenocarcinoma was detected on biopsy, and surgery was performed with a preoperative diagnosis of cholangiocarcinoma of the distal CBD. Pathological examination revealed adenocarcinoma of the CBD mucosa (20%) and NEC of the CBD wall (80%). The final pathological diagnosis was small-cell NEC of the EHBD. His post-operative course was good, and there was no recurrence for 4 months after surgery. Herein, we report a case of resected EHBD NEC and a literature review.

Primary hepatic neuroendocrine tumor with multiple liver metastases: A case report with literature review

Primary hepatic neuroendocrine tumors (PHNETs) are a group of extremely rare tumors that are difficult to differentiate from common hepatic malignancies on routine imaging studies. By presenting a case of PHNET, we herein introduce our experience with the diagnosis, differential diagnosis, and management of patients with this rare disease. The patient was preoperatively diagnosed with hepatic hydatidosis but postoperatively diagnosed with a PHNET with multiple liver metastases. He was successfully treated with transcatheter arterial chemoembolization. This case indicates that the clinical diagnosis of PHNET is a medical challenge. Although peptide receptor radionuclide therapy has been suggested as the mainstay of treatment for well-differentiated somatostatin receptor-positive PHNETs, patients with a large tumor burden may also benefit from transcatheter arterial chemoembolization.

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

Neuroendocrine neoplasm (NEN) comprises a group of tumors that exhibit neuroendocrine phenotypes. NEN is subclassified into neuroendocrine tumor (NET), neuroendocrine carcinoma (NEC) and mixed adenoendocrine carcinoma (MANEC), based on histopathological parameters. NEN in the extrahepatic biliary tract (EHBT) is uncommon. Little is known about its clinicopathological features and prognostic indicators. The present study presented a case of MANEC in the distal common bile duct (CBD) and reviewed previous cases of NENs in the EHBT to characterize the clinical settings of this disease entity and to identify influencing factors of survival outcomes. A 64-year-old Chinese woman presented with abdominal pain and jaundice. Imaging studies demonstrated malignant stenosis in the distal CBD. Bile duct brush cytology revealed small clusters of atypical cells. Following an initial diagnosis of distal cholangiocarcinoma (CCA), the patient underwent pancreaticoduodenectomy. Histological analysis combined with immunohistochemical investigation of the resected specimen revealed a collision tumor that was composed of poorly differentiated adenocarcinoma and NEC. Each histological component accounted for >30% of the tumor. The definitive diagnosis was a MANEC in the distal CBD. Multiple intrahepatic and pulmonary metastases were observed postoperatively over 8 months. The patient succumbed to the disease 12 months after surgery. In conclusion, NEN occurs infrequently in the EHBT, with NET being the predominant type. NEN in the EHBT is extremely challenging to diagnose preoperatively due to its tendency to mimic CCA. Patients with NEN in the EHBT exhibited extremely distinct oncology outcomes according to pathological types. Additionally, old age (>60 years) and the presence of tumor recurrence were associated with decreased survival of patients with NEN.

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

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.