A malignant epithelial neoplasm composed of a mixture of neuroendocrine cells with morphologic and immunohistochemical characteristics of carcinoid tumor and malignant glandular cells. The disease is combined carcinoid and adenocarcinoma (Monarch Disease Ontology entry MONDO_0021659). Also known as: adenocarcinoid neoplasm, adenocarcinoid tumor, adenocarcinoid tumour, combined carcinoid neoplasm and adenocarcinoma, combined carcinoid tumor and adenocarcinoma, combined carcinoid tumour and adenocarcinoma, composite carcinoid, composite carcinoid neoplasm.