Intra-ampullary papillary-tubular neoplasm combined with ampullary neuroendocrine carcinoma: A case report

Figure 3 Combined intra-ampullary papillary-tubular neoplasm and neuroendocrine carcinoma. A: Low power magnification depicting abrupt transition from the papillary tumor (upper and middle left) to solid nodular proliferation (middle and right); B: Higher magnification of the solid component, consistent with poorly differentiated neuroendocrine carcinoma; C: Immunohistochemistry for insulinoma-associated protein 1 depicting diffuse nuclear positivity; D: Immunohistochemistry revealing a 100% Ki-67 index in tumor cells.