Adenomatous Polyps: Benign neoplasms derived from glandular epithelium. (From Stedman, 25th ed)Colonic Polyps: Discrete tissue masses that protrude into the lumen of the COLON. These POLYPS are connected to the wall of the colon either by a stalk, pedunculus, or by a broad base.Polyps: Discrete abnormal tissue masses that protrude into the lumen of the DIGESTIVE TRACT or the RESPIRATORY TRACT. Polyps can be spheroidal, hemispheroidal, or irregular mound-shaped structures attached to the MUCOUS MEMBRANE of the lumen wall either by a stalk, pedunculus, or by a broad base.Adenomatous Polyposis Coli: A polyposis syndrome due to an autosomal dominant mutation of the APC genes (GENES, APC) on CHROMOSOME 5. The syndrome is characterized by the development of hundreds of ADENOMATOUS POLYPS in the COLON and RECTUM of affected individuals by early adulthood.Intestinal Polyps: Discrete abnormal tissue masses that protrude into the lumen of the INTESTINE. A polyp is attached to the intestinal wall either by a stalk, pedunculus, or by a broad base.Adenoma: A benign epithelial tumor with a glandular organization.Colonoscopy: Endoscopic examination, therapy or surgery of the luminal surface of the colon.Adenomatous Polyposis Coli Protein: A negative regulator of beta-catenin signaling which is mutant in ADENOMATOUS POLYPOSIS COLI and GARDNER SYNDROME.Colorectal Neoplasms: Tumors or cancer of the COLON or the RECTUM or both. Risk factors for colorectal cancer include chronic ULCERATIVE COLITIS; FAMILIAL POLYPOSIS COLI; exposure to ASBESTOS; and irradiation of the CERVIX UTERI.Colonic Neoplasms: Tumors or cancer of the COLON.Nasal Polyps: Focal accumulations of EDEMA fluid in the NASAL MUCOSA accompanied by HYPERPLASIA of the associated submucosal connective tissue. Polyps may be NEOPLASMS, foci of INFLAMMATION, degenerative lesions, or malformations.Sigmoidoscopy: Endoscopic examination, therapy or surgery of the sigmoid flexure.Colonography, Computed Tomographic: A non-invasive imaging method that uses computed tomographic data combined with specialized imaging software to examine the colon.Colon: The segment of LARGE INTESTINE between the CECUM and the RECTUM. It includes the ASCENDING COLON; the TRANSVERSE COLON; the DESCENDING COLON; and the SIGMOID COLON.Hyperplasia: An increase in the number of cells in a tissue or organ without tumor formation. It differs from HYPERTROPHY, which is an increase in bulk without an increase in the number of cells.Rectal Neoplasms: Tumors or cancer of the RECTUM.Intestinal Mucosa: Lining of the INTESTINES, consisting of an inner EPITHELIUM, a middle LAMINA PROPRIA, and an outer MUSCULARIS MUCOSAE. In the SMALL INTESTINE, the mucosa is characterized by a series of folds and abundance of absorptive cells (ENTEROCYTES) with MICROVILLI.Rectum: The distal segment of the LARGE INTESTINE, between the SIGMOID COLON and the ANAL CANAL.Barium Sulfate: A compound used as an x-ray contrast medium that occurs in nature as the mineral barite. It is also used in various manufacturing applications and mixed into heavy concrete to serve as a radiation shield.Gardner Syndrome: A variant of ADENOMATOUS POLYPOSIS COLI caused by mutation in the APC gene (GENES, APC) on CHROMOSOME 5. It is characterized by not only the presence of multiple colonic polyposis but also extracolonic ADENOMATOUS POLYPS in the UPPER GASTROINTESTINAL TRACT; the EYE; the SKIN; the SKULL; and the FACIAL BONES; as well as malignancy in organs other than the GI tract.Cecal Neoplasms: Tumors or cancer of the CECUM.Enema: A solution or compound that is introduced into the RECTUM with the purpose of cleansing the COLON or for diagnostic procedures.Genes, APC: Tumor suppressor genes located in the 5q21 region on the long arm of human chromosome 5. The mutation of these genes is associated with familial adenomatous polyposis (ADENOMATOUS POLYPOSIS COLI) and GARDNER SYNDROME, as well as some sporadic colorectal cancers.Precancerous Conditions: Pathological processes that tend eventually to become malignant. (From Dorland, 27th ed)Sulindac: A sulfinylindene derivative prodrug whose sulfinyl moiety is converted in vivo to an active NSAID analgesic. Specifically, the prodrug is converted by liver enzymes to a sulfide which is excreted in the bile and then reabsorbed from the intestine. This helps to maintain constant blood levels with reduced gastrointestinal side effects.Rectal Diseases: Pathological developments in the RECTUM region of the large intestine (INTESTINE, LARGE).Sigmoid Neoplasms: Tumors or cancer of the SIGMOID COLON.Adenocarcinoma: A malignant epithelial tumor with a glandular organization.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)Occult Blood: Chemical, spectroscopic, or microscopic detection of extremely small amounts of blood.Diverticulum, Colon: A pouch or sac opening from the COLON.Colon, Transverse: The segment of LARGE INTESTINE between ASCENDING COLON and DESCENDING COLON. It passes from the RIGHT COLIC FLEXURE across the ABDOMEN, then turns sharply at the left colonic flexure into the descending colon.Germ-Line Mutation: Any detectable and heritable alteration in the lineage of germ cells. Mutations in these cells (i.e., "generative" cells ancestral to the gametes) are transmitted to progeny while those in somatic cells are not.beta Catenin: A multi-functional catenin that participates in CELL ADHESION and nuclear signaling. Beta catenin binds CADHERINS and helps link their cytoplasmic tails to the ACTIN in the CYTOSKELETON via ALPHA CATENIN. It also serves as a transcriptional co-activator and downstream component of WNT PROTEIN-mediated SIGNAL TRANSDUCTION PATHWAYS.Anti-Inflammatory Agents, Non-Steroidal: Anti-inflammatory agents that are non-steroidal in nature. In addition to anti-inflammatory actions, they have analgesic, antipyretic, and platelet-inhibitory actions.They act by blocking the synthesis of prostaglandins by inhibiting cyclooxygenase, which converts arachidonic acid to cyclic endoperoxides, precursors of prostaglandins. Inhibition of prostaglandin synthesis accounts for their analgesic, antipyretic, and platelet-inhibitory actions; other mechanisms may contribute to their anti-inflammatory effects.Case-Control Studies: Studies which start with the identification of persons with a disease of interest and a control (comparison, referent) group without the disease. The relationship of an attribute to the disease is examined by comparing diseased and non-diseased persons with regard to the frequency or levels of the attribute in each group.Endoscopy: Procedures of applying ENDOSCOPES for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. transluminal, to examine or perform surgery on the interior parts of the body.Fibromatosis, Aggressive: A childhood counterpart of abdominal or extra-abdominal desmoid tumors, characterized by firm subcutaneous nodules that grow rapidly in any part of the body but do not metastasize. The adult form of abdominal fibromatosis is FIBROMATOSIS, ABDOMINAL. (Stedman, 25th ed)Risk Factors: An aspect of personal behavior or lifestyle, environmental exposure, or inborn or inherited characteristic, which, on the basis of epidemiologic evidence, is known to be associated with a health-related condition considered important to prevent.Mutation: Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.Duodenal Neoplasms: Tumors or cancer of the DUODENUM.Biopsy: Removal and pathologic examination of specimens in the form of small pieces of tissue from the living body.Mass Screening: Organized periodic procedures performed on large groups of people for the purpose of detecting disease.Immunohistochemistry: Histochemical localization of immunoreactive substances using labeled antibodies as reagents.Cytoskeletal Proteins: Major constituent of the cytoskeleton found in the cytoplasm of eukaryotic cells. They form a flexible framework for the cell, provide attachment points for organelles and formed bodies, and make communication between parts of the cell possible.Carcinoma: A malignant neoplasm made up of epithelial cells tending to infiltrate the surrounding tissues and give rise to metastases. It is a histological type of neoplasm but is often wrongly used as a synonym for "cancer." (From Dorland, 27th ed)Intestinal Neoplasms: Tumors or cancer of the INTESTINES.Vegetables: A food group comprised of EDIBLE PLANTS or their parts.Adenomatosis, Pulmonary: A neoplastic disease in which the alveoli and distal bronchi are filled with mucus and mucus-secreting columnar epithelial cells. It is characterized by abundant, extremely tenacious sputum, chills, fever, cough, dyspnea, and pleuritic pain. (Stedman, 25th ed)Retrospective Studies: Studies used to test etiologic hypotheses in which inferences about an exposure to putative causal factors are derived from data relating to characteristics of persons under study or to events or experiences in their past. The essential feature is that some of the persons under study have the disease or outcome of interest and their characteristics are compared with those of unaffected persons.