TFF1 and neuroendocrine neoplasm: The highest rate of TFF1 positivity was found in mucinous carcinomas of the ovary (76.2%), colorectal adenomas and adenocarcinomas (47.1–75.0%), neoplasms of the breast (11.8–72.9%), bilio-pancreatic adenocarcinomas (42.1–62.5%), gastro-esophageal adenocarcinomas (40.4–50.0%), neuroendocrine neoplasms of various sites of origin (7.1–45.5%), adenocarcinomas of the cervix (39.1%), and in urothelial neoplasms (5.5–24.3%).