The right colic flexure or hepatic flexure (as it is next to the liver) is the sharp bend between the ascending colon and the transverse colon. Note that "right" refers to the patient's anatomical right, which may be depicted on the left of a diagram. The right colic flexure is also known as the hepatic flexure, and the left colic flexure is also known as the splenic flexure. doi:10.1148/radiol.In the anatomy of the human digestive tract, there are two colic flexures, or curvatures in the transverse colon. Sigmoid Cancer Versus Chronic Diverticular Disease: Differentiating Features at CT Colonography. BRAF-Mutated Colorectal Cancer: Clinical and Molecular Insights. Association Between Streptococcus Bovis and Colon Cancer. Spiral CT of Colon Cancer: Imaging Features and Role in Management. Current Medical Diagnosis & Treatment 2007. Robbins and Cotran Pathologic Basis of Disease. Vinay Kumar, Stanley Leonard Robbins, Abul K. Other imaging differential considerations on CT include: On CT colonography, the two most useful discriminators of colorectal carcinoma and diverticular disease are absence of diverticula within the structured segment, and shouldered edges, with both features having a high negative and positive predictive value for carcinoma 8. Other features pointing to carcinoma include a shorter segment length, destroyed mucosal folds, straightening of the segment, absence of thickened fascia, and more and larger locoregional nodes. for first-degree relatives of patients with colon cancer: screening should start at age 40.polyps 50 years of age: an annual fecal occult blood test (often a fecal immunochemical test (FIT)) and sigmoidoscopy/ barium enema every 3 to 5 years.Radiographic features Fluoroscopy Barium enema primary colorectal small cell carcinoma: extremely rareĬolorectal cancers can be found anywhere from the cecum to the rectum, in the following distribution 2,5:Īpproximately 10% of colorectal cancers have a BRAF mutation, which is more common in females, right colon colorectal cancer, advanced stage at diagnosis, and a mucinous histology 7.Metastases may be widespread in advanced disease, although the liver is by far the most common site involved. These are typically scirrhous adenocarcinomas (signet-ring type). Rarely the malignant cells will widely invade the submucosa, analogous to linitis plastic a of the stomach. left-sided tumors present earlier with altered bowel habitĬolorectal cancers, 98% of which are adenocarcinomas, arise in the vast majority of cases from pre-existing colonic adenomas ( neoplastic polyps), which progressively undergo a malignant transformation as they accumulate additional mutations 2 (so-called multi-hit hypothesis).right-sided tumors are larger and present with a mass, distant disease or iron deficiency anemia.bacteremia or bacterial endocarditis with Streptococcus bovis ( Streptococcus gallolyticus) 6.respiratory symptoms from lung metastases) However initial manifestation may be acute: iron-deficiency anemia (chronic occult blood loss).altered bowel habit (constipation and/or diarrhea).hereditary non-polyposis colon cancer syndrome (HNPCC)Ĭlinical presentation is typically insidious:.familial adenomatous polyposis syndrome (FAP).Recognized hereditary syndromes are seen in 6% of colorectal cancers. a family history of benign/malignant colorectal tumors.Crohn disease (particularly in bypassed loops/in vicinity of chronic fistula).low fiber and high fat and animal protein diet.Risk factorsĪ number of predisposing factors have been identified, including: There is also a slight male predilection for rectal cancers, not found in tumors elsewhere in the colon. Colorectal cancer is common, accounting for 15% of all newly diagnosed cancers, and tends to be a disease of the elderly, with the median age of diagnosis between 60 and 80 years of age 2, slightly younger for rectal cancer.
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