Neuroendocrine carcinoma of the extrahepatic bile duct: Case report and literature review

Figure 2 Histologic features of the hilar neoplasm. A: The tumor cells were arranged in cellular nests and sheets with little intervening fibrovascular stroma [Hematoxylin and eosin (HE), × 200]; B: The tumor cells had a small to moderate amount of amphophilic cytoplasm and medium to large hyperchromatic nuclei with fine to coarse granular chromatin and occasional small nucleoli (HE, × 400); C: The tumor cells were strongly positive for synaptophysin (× 400); D: 70%-80% of the tumor cells were positive for Ki-67 (× 200).