Pancreatic Cyst: A true cyst of the PANCREAS, distinguished from the much more common PANCREATIC PSEUDOCYST by possessing a lining of mucous EPITHELIUM. Pancreatic cysts are categorized as congenital, retention, neoplastic, parasitic, enterogenous, or dermoid. Congenital cysts occur more frequently as solitary cysts but may be multiple. Retention cysts are gross enlargements of PANCREATIC DUCTS secondary to ductal obstruction. (From Bockus Gastroenterology, 4th ed, p4145)Cyst Fluid: Liquid material found in epithelial-lined closed cavities or sacs.Cysts: Any fluid-filled closed cavity or sac that is lined by an EPITHELIUM. Cysts can be of normal, abnormal, non-neoplastic, or neoplastic tissues.Cystadenocarcinoma, Mucinous: A malignant cystic or semisolid tumor most often occurring in the ovary. Rarely, one is solid. This tumor may develop from a mucinous cystadenoma, or it may be malignant at the onset. The cysts are lined with tall columnar epithelial cells; in others, the epithelium consists of many layers of cells that have lost normal structure entirely. In the more undifferentiated tumors, one may see sheets and nests of tumor cells that have very little resemblance to the parent structure. (Hughes, Obstetric-Gynecologic Terminology, 1972, p184)Cystadenoma: A benign neoplasm derived from glandular epithelium, in which cystic accumulations of retained secretions are formed. In some instances, considerable portions of the neoplasm, or even the entire mass, may be cystic. (Stedman, 25th ed)Pancreatic Pseudocyst: Cyst-like space not lined by EPITHELIUM and contained within the PANCREAS. Pancreatic pseudocysts account for most of the cystic collections in the pancreas and are often associated with chronic PANCREATITIS.Cystadenoma, Serous: A cystic tumor of the ovary, containing thin, clear, yellow serous fluid and varying amounts of solid tissue, with a malignant potential several times greater than that of mucinous cystadenoma (CYSTADENOMA, MUCINOUS). It can be unilocular, parvilocular, or multilocular. It is often bilateral and papillary. The cysts may vary greatly in size. (Dorland, 27th ed; from Hughes, Obstetric-Gynecologic Terminology, 1972)Cystadenoma, Mucinous: A multilocular tumor with mucin secreting epithelium. They are most often found in the ovary, but are also found in the pancreas, appendix, and rarely, retroperitoneal and in the urinary bladder. They are considered to have low-grade malignant potential.Cystadenocarcinoma: A malignant neoplasm derived from glandular epithelium, in which cystic accumulations of retained secretions are formed. The neoplastic cells manifest varying degrees of anaplasia and invasiveness, and local extension and metastases occur. Cystadenocarcinomas develop frequently in the ovaries, where pseudomucinous and serous types are recognized. (Stedman, 25th ed)Neoplasms, Cystic, Mucinous, and Serous: Neoplasms containing cyst-like formations or producing mucin or serum.Endosonography: Ultrasonography of internal organs using an ultrasound transducer sometimes mounted on a fiberoptic endoscope. In endosonography the transducer converts electronic signals into acoustic pulses or continuous waves and acts also as a receiver to detect reflected pulses from within the organ. An audiovisual-electronic interface converts the detected or processed echo signals, which pass through the electronics of the instrument, into a form that the technologist can evaluate. The procedure should not be confused with ENDOSCOPY which employs a special instrument called an endoscope. The "endo-" of endosonography refers to the examination of tissue within hollow organs, with reference to the usual ultrasonography procedure which is performed externally or transcutaneously.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).von Hippel-Lindau Disease: An autosomal dominant disorder caused by mutations in a tumor suppressor gene. This syndrome is characterized by abnormal growth of small blood vessels leading to a host of neoplasms. They include HEMANGIOBLASTOMA in the RETINA; CEREBELLUM; and SPINAL CORD; PHEOCHROMOCYTOMA; pancreatic tumors; and renal cell carcinoma (see CARCINOMA, RENAL CELL). Common clinical signs include HYPERTENSION and neurological dysfunctions.Adenocarcinoma, Mucinous: An adenocarcinoma producing mucin in significant amounts. (From Dorland, 27th ed)Incidental Findings: Unanticipated information discovered in the course of testing or medical care. Used in discussions of information that may have social or psychological consequences, such as when it is learned that a child's biological father is someone other than the putative father, or that a person tested for one disease or disorder has, or is at risk for, something else.Cholangiopancreatography, Magnetic Resonance: Non-invasive diagnostic technique for visualizing the PANCREATIC DUCTS and BILE DUCTS without the use of injected CONTRAST MEDIA or x-ray. MRI scans provide excellent sensitivity for duct dilatation, biliary stricture, and intraductal abnormalities.Ovarian Cysts: General term for CYSTS and cystic diseases of the OVARY.Pancreatectomy: Surgical removal of the pancreas. (Dorland, 28th ed)Biopsy, Fine-Needle: Using fine needles (finer than 22-gauge) to remove tissue or fluid specimens from the living body for examination in the pathology laboratory and for disease diagnosis.Epidermal Cyst: Intradermal or subcutaneous saclike structure, the wall of which is stratified epithelium containing keratohyalin granules.Carcinoma, Pancreatic Ductal: Carcinoma that arises from the PANCREATIC DUCTS. It accounts for the majority of cancers derived from the PANCREAS.Pancreas: A nodular organ in the ABDOMEN that contains a mixture of ENDOCRINE GLANDS and EXOCRINE GLANDS. The small endocrine portion consists of the ISLETS OF LANGERHANS secreting a number of hormones into the blood stream. The large exocrine portion (EXOCRINE PANCREAS) is a compound acinar gland that secretes several digestive enzymes into the pancreatic ductal system that empties into the DUODENUM.Carcinoembryonic Antigen: A glycoprotein that is secreted into the luminal surface of the epithelia in the gastrointestinal tract. It is found in the feces and pancreaticobiliary secretions and is used to monitor the response to colon cancer treatment.Mediastinal Cyst: Cysts of one of the parts of the mediastinum: the superior part, containing the trachea, esophagus, thoracic duct and thymus organs; the inferior middle part, containing the pericardium; the inferior anterior part containing some lymph nodes; and the inferior posterior part, containing the thoracic duct and esophagus.Mucins: High molecular weight mucoproteins that protect the surface of EPITHELIAL CELLS by providing a barrier to particulate matter and microorganisms. Membrane-anchored mucins may have additional roles concerned with protein interactions at the cell surface.Synovial Cyst: Non-neoplastic tumor-like lesions at joints, developed from the SYNOVIAL MEMBRANE of a joint through the JOINT CAPSULE into the periarticular tissues. They are filled with SYNOVIAL FLUID with a smooth and translucent appearance. A synovial cyst can develop from any joint, but most commonly at the back of the knee, where it is known as POPLITEAL CYST.Bone Cysts: Benign unilocular lytic areas in the proximal end of a long bone with well defined and narrow endosteal margins. The cysts contain fluid and the cyst walls may contain some giant cells. Bone cysts usually occur in males between the ages 3-15 years.Bronchogenic Cyst: A usually spherical cyst, arising as an embryonic out-pouching of the foregut or trachea. It is generally found in the mediastinum or lung and is usually asymptomatic unless it becomes infected.Tomography, X-Ray Computed: Tomography using x-ray transmission and a computer algorithm to reconstruct the image.Dermoid Cyst: A tumor consisting of displaced ectodermal structures along the lines of embryonic fusion, the wall being formed of epithelium-lined connective tissue, including skin appendages, and containing keratin, sebum, and hair. (Stedman, 25th ed)Molecular Diagnostic Techniques: MOLECULAR BIOLOGY techniques used in the diagnosis of disease.