Ampulla of Vater: A dilation of the duodenal papilla that is the opening of the juncture of the COMMON BILE DUCT and the MAIN PANCREATIC DUCT, also known as the hepatopancreatic ampulla.Common Bile Duct Neoplasms: Tumor or cancer of the COMMON BILE DUCT including the AMPULLA OF VATER and the SPHINCTER OF ODDI.Pancreaticoduodenectomy: The excision of the head of the pancreas and the encircling loop of the duodenum to which it is connected.Fallopian Tubes: A pair of highly specialized muscular canals extending from the UTERUS to its corresponding OVARY. They provide the means for OVUM collection, and the site for the final maturation of gametes and FERTILIZATION. The fallopian tube consists of an interstitium, an isthmus, an ampulla, an infundibulum, and fimbriae. Its wall consists of three histologic layers: serous, muscular, and an internal mucosal layer lined with both ciliated and secretory cells.Duodenal Neoplasms: Tumors or cancer of the DUODENUM.Duodenoscopy: Endoscopic examination, therapy or surgery of the luminal surface of the duodenum.Cholangiopancreatography, Endoscopic Retrograde: Fiberoptic endoscopy designed for duodenal observation and cannulation of VATER'S AMPULLA, in order to visualize the pancreatic and biliary duct system by retrograde injection of contrast media. Endoscopic (Vater) papillotomy (SPHINCTEROTOMY, ENDOSCOPIC) may be performed during this procedure.Duodenoscopes: Endoscopes for examining the interior of the duodenum.Common Bile Duct Diseases: Diseases of the COMMON BILE DUCT including the AMPULLA OF VATER and the SPHINCTER OF ODDI.Carcinoma, Signet Ring Cell: A poorly differentiated adenocarcinoma in which the nucleus is pressed to one side by a cytoplasmic droplet of mucus. It usually arises in the gastrointestinal system.Anus, Imperforate: A congenital abnormality characterized by the persistence of the anal membrane, resulting in a thin membrane covering the normal ANAL CANAL. Imperforation is not always complete and is treated by surgery in infancy. This defect is often associated with NEURAL TUBE DEFECTS; MENTAL RETARDATION; and DOWN SYNDROME.Bile Duct Neoplasms: Tumors or cancer of the BILE DUCTS.Jaundice: A clinical manifestation of HYPERBILIRUBINEMIA, characterized by the yellowish staining of the SKIN; MUCOUS MEMBRANE; and SCLERA. Clinical jaundice usually is a sign of LIVER dysfunction.Biliary Tract Neoplasms: Tumors or cancer in the BILIARY TRACT including the BILE DUCTS and the GALLBLADDER.Duodenum: The shortest and widest portion of the SMALL INTESTINE adjacent to the PYLORUS of the STOMACH. It is named for having the length equal to about the width of 12 fingers.Sperm Transport: Passive or active movement of SPERMATOZOA from the testicular SEMINIFEROUS TUBULES through the male reproductive tract as well as within the female reproductive tract.Adenoma, Villous: An adenoma of the large intestine. It is usually a solitary, sessile, often large, tumor of colonic mucosa composed of mucinous epithelium covering delicate vascular projections. Hypersecretion and malignant changes occur frequently. (Stedman, 25th ed)Pancreatic Ducts: Ducts that collect PANCREATIC JUICE from the PANCREAS and supply it to the DUODENUM.Krukenberg Tumor: Mucocellular carcinoma of the ovary, usually metastatic from the gastrointestinal tract, characterized by areas of mucoid degeneration and the presence of signet-ring-like cells. It accounts for 30%-40% of metastatic cancers to the ovaries and possibly 1%-2% of all malignant ovarian tumors. The lesions may not be discovered until the primary disease is advanced, and most patients die of their disease within a year. In some cases, a primary tumor is not found. (From Dorland, 27th ed; Holland et al., Cancer Medicine, 3d ed, p1685)Gallstones: Solid crystalline precipitates in the BILIARY TRACT, usually formed in the GALLBLADDER, resulting in the condition of CHOLELITHIASIS. Gallstones, derived from the BILE, consist mainly of calcium, cholesterol, or bilirubin.Adenocarcinoma: A malignant epithelial tumor with a glandular organization.Carcinoid Tumor: A usually small, slow-growing neoplasm composed of islands of rounded, oxyphilic, or spindle-shaped cells of medium size, with moderately small vesicular nuclei, and covered by intact mucosa with a yellow cut surface. The tumor can occur anywhere in the gastrointestinal tract (and in the lungs and other sites); approximately 90% arise in the appendix. It is now established that these tumors are of neuroendocrine origin and derive from a primitive stem cell. (From Stedman, 25th ed & Holland et al., Cancer Medicine, 3d ed, p1182)Common Bile Duct: The largest bile duct. It is formed by the junction of the CYSTIC DUCT and the COMMON HEPATIC DUCT.Carcinoma, Neuroendocrine: A group of carcinomas which share a characteristic morphology, often being composed of clusters and trabecular sheets of round "blue cells", granular chromatin, and an attenuated rim of poorly demarcated cytoplasm. Neuroendocrine tumors include carcinoids, small ("oat") cell carcinomas, medullary carcinoma of the thyroid, Merkel cell tumor, cutaneous neuroendocrine carcinoma, pancreatic islet cell tumors, and pheochromocytoma. Neurosecretory granules are found within the tumor cells. (Segen, Dictionary of Modern Medicine, 1992)Duodenal Diseases: Pathological conditions in the DUODENUM region of the small intestine (INTESTINE, SMALL).Ovum Transport: Transport of the OVUM or fertilized ovum (ZYGOTE) from the mammalian oviduct (FALLOPIAN TUBES) to the site of EMBRYO IMPLANTATION in the UTERUS.Keratin-7: A type II keratin found associated with KERATIN-19 in ductal epithelia and gastrointestinal epithelia.Neoplasms, Multiple Primary: Two or more abnormal growths of tissue occurring simultaneously and presumed to be of separate origin. The neoplasms may be histologically the same or different, and may be found in the same or different sites.Biliary Tract Surgical Procedures: Any surgical procedure performed on the biliary tract.Hair Cells, Ampulla: Sensory cells in the ampullary crest of each of the semicircular ducts, with their apical STEREOCILIA embedded in a wedge-shaped gelatinous cupula. These hair cells sense the movement of ENDOLYMPH resulting from angular acceleration of the head, and send signals via the VESTIBULAR NERVE to the brain to maintain balance.Endolymph: The lymph fluid found in the membranous labyrinth of the ear. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Semicircular Canals: Three long canals (anterior, posterior, and lateral) of the bony labyrinth. They are set at right angles to each other and are situated posterosuperior to the vestibule of the bony labyrinth (VESTIBULAR LABYRINTH). The semicircular canals have five openings into the vestibule with one shared by the anterior and the posterior canals. Within the canals are the SEMICIRCULAR DUCTS.Pancreatic Neoplasms: Tumors or cancer of the PANCREAS. Depending on the types of ISLET CELLS present in the tumors, various hormones can be secreted: GLUCAGON from PANCREATIC ALPHA CELLS; INSULIN from PANCREATIC BETA CELLS; and SOMATOSTATIN from the SOMATOSTATIN-SECRETING CELLS. Most are malignant except the insulin-producing tumors (INSULINOMA).