75–95% of<unk>  cases occur in people with little or no genetic risk. Risk factors include older age, male sex, high intake of fat, sugar, alcohol, red meat, processed meats, obesity, smoking, and a lack of physical exercise. Approximately 10% of cases are linked to insufficient activity. The risk from alcohol appears to increase at greater than one drink per day. Drinking 5 glasses of water a day is linked to a decrease in the risk of<unk>  and adenomatous polyps. Streptococcus gallolyticus is associated with<unk> . Some strains of Streptococcus bovis/Streptococcus equinus complex are consumed by millions of people daily and thus may be safe. 25 to 80% of people with Streptococcus bovis/gallolyticus bacteremia have concomitant<unk>  tumors. Seroprevalence of Streptococcus bovis/gallolyticus is considered as a candidate practical marker for the early prediction of an underlying bowel lesion at high risk population. It has been suggested that the presence of antibodies to Streptococcus bovis/gallolyticus antigens or the antigens themselves in the bloodstream may act as markers for the carcinogenesis in the colon. Pathogenic Escherichia coli may increase the risk of<unk>  by producing the genotoxic metabolite, colibactin. Inflammatory bowel disease People with inflammatory bowel disease (ulcerative colitis and Crohn's disease) are at increased risk of colon<unk> . The risk increases the longer a person has the disease, and the worse the severity of inflammation. In these high risk groups, both prevention with aspirin and regular colonoscopies are recommended. Endoscopic surveillance in this high-risk population may reduce the development of<unk>  through early diagnosis and may also reduce the chances of dying from colon<unk> . People with inflammatory bowel disease account for less than 2% of colon<unk>  cases yearly. In those with Crohn's disease, 2% get<unk>  after 10 years, 8% after 20 years, and 18% after 30 years. In people who have ulcerative colitis, approximately 16% develop either a<unk>  precursor or<unk>  of the colon over 30 years. Genetics Those with a family history in two or more first-degree relatives (such as a parent or sibling) have a two to threefold greater risk of disease and this group accounts for about 20% of all cases. A number of genetic syndromes are also associated with higher rates of<unk> . The most common of these is hereditary nonpolyposis<unk>  (HNPCC or Lynch syndrome) which is present in about 3% of people with<unk> . Other syndromes that are strongly associated with<unk>  include Gardner syndrome and familial adenomatous polyposis (FAP). For people with these syndromes,<unk>  almost always occurs and makes up 1% of the<unk>  cases. A total proctocolectomy may be recommended for people with FAP as a preventive measure due to the high risk of malignancy. Colectomy, removal of the colon, may not suffice as a preventive measure because of the high risk of rectal<unk>  if the rectum remains. The most common polyposis syndrome affecting the colon is serrated polyposis syndrome, which is associated with a 25-40% risk of<unk> . Mutations in the pair of genes (POLE and POLD1) have been associated with familial colon<unk> . Most deaths due to colon<unk>  are associated with metastatic disease. A gene that appears to contribute to the potential for metastatic disease, metastasis associated in colon<unk>  1 (MACC1), has been isolated. It is a transcriptional factor that influences the expression of hepatocyte growth factor. This gene is associated with the proliferation, invasion and scattering of colon<unk>  cells in cell culture, and tumor growth and metastasis in mice. MACC1 may be a potential target for<unk>  intervention, but this possibility needs to be confirmed with clinical studies. Epigenetic factors, such as abnormal DNA methylation of tumor suppressor promoters, play a role in the development of<unk> . Ashkenazi Jews have a 6% higher risk rate of getting adenomas and then colon<unk>  due to mutations in the APC gene being more common.
Colorectal cancer
Irritable bowel syndrome
Anal cancer
Gastrointestinal cancer
Pancreatic cancer
Small intestine cancer
Colitis
Liver cancer