%0 Journal Article
%T Diagnosis of Mixed Adenoneuroendocrine Carcinoma (MANEC) after Neoadjuvant Chemotherapy for Pancreatic and Gastric Adenocarcinoma: Two Case Reports and a Review of the Literature
%A Alberto Zaniboni
%A Barbara Liserre
%A Denise Bianchi
%A Ester Oneda
%A Fausto Zorzi
%A Giordano Savelli
%A Luigina Rota
%J Archive of "Case Reports in Oncology".
%D 2019
%R 10.1159/000501200
%X Mixed adenoneuroendocrine carcinoma (MANEC) is a rare tumor of the gastrointestinal tract involving both epithelial and neuroendocrine (NE) components, each of which represents at least 30% of the tumor. Because of the low frequency of this histotype, only a few cases have been described. In this report we discuss two cases treated with neoadjuvant chemotherapy: a pancreatic adenocarcinoma and a gastric adenocarcinoma. The histopathological specimens examined after surgery showed an additional NE component with a possible indication of the MANEC histotype. We hypothesize two possible explanations: tumor NE cells are more chemo-resistant than adenocarcinoma cells, and cytotoxic injury induces NE differentiation in tumor cells. The clinical significance and prognostic value of endocrine differentiation, however, remain controversial issues
%K Mixed adenoneuroendocrine carcinoma
%K Neoadjuvant chemotherapy
%K Neuroendocrine differentiation
%U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6600038/