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Colon polyps

MEDICAL ENCYCLOPEDIA 
Colon polyps
Colon polyps
Causes and Risk Factors
Colon polyp symptoms
Diagnosis
Treatment

Colon Polyps
Polyps are one of the most common conditions that affect the colon and rectum, occurring in 15 to 20 percent of the adult population. Although most polyps are benign, certain polyps can be related to cancer. In fact, nearly all colon cancers develop from polyps, but the polyps grow slowly, usually over a period of years. But what types of colonic polyps do doctors describe? And what are colonic polyps to begin?

Digestive anatomy
The digestive tract stretches from the mouth to the anus. As food travels along this 30-foot tract, nutrients are broken down to be absorbed by the body and used to build cells and produce energy. The last part of the digestive tract is a long muscular tube called the large intestine. The large intestine absorbs water from stool and changes it from a liquid to a solid. Stool is the waste that passes through the rectum and anus as a bowel movement.

Colon - The colon is the upper 4 to 6 feet of the large intestine. The colon's main function is to absorb water, salt and other minerals from colon contents.

Rectum - The rectum makes up the lower 8 to 10 inches of the large intestine. The rectum stores waste until it's eliminated from the body.

What is a colon polyp?
Healthy cells in the body grow and divide in an orderly way — a process that's controlled by two groups of genes. Mutations in any of these genes can cause cells to continue dividing even when new cells aren't needed. In the colon and rectum, this unregulated growth can cause polyps to form.

A colon polyp is a small clump of cells (or growth) that forms on the surface lining of the large intestine. Polyps can occur throughout the large intestine or rectum, but are more commonly found in the left colon, sigmoid colon, or rectum. Sometimes, a person can have more than one colon polyp. Colon polyps can be small or large and flat (sessile) or raised and attached with a stalk-like base (pedunculated). Colon polyps can also have a wide base (villous) or a thin base (mushroom or filament). Over a long period of time, some of these polyps may become malignant cancer, especially villous polyps. In general, the larger a polyp, the greater the likelihood of cancer.

Types of colon polyps
Although most colon polyps are harmless, some become cancerous over time The majority of polyps aren't cancerous (malignant). Yet like most cancers, polyps are the result of abnormal cell growth. But some types of polyps may already be cancer or can become cancer. The main types of colon polyps include:

  1. Adenomatous - Most polyps fall under this category. Only a small percentage of these polyps actually become cancerous.

  2. Hyperplastic - These polyps occur most often in the left descending colon and rectum. Usually less than 0.5 centimeters, they're very rarely malignant.

  3. Inflammatory - These polyps may follow ulcerative colitis or Crohn's disease of the colon and are not a significant threat of colon cancer.

  4. Inherited colonic polyps - A small percentage of colon cancers result from gene mutations. Some of these cancers are inherited from one defective gene from either one of your parents, giving you a 50 percent chance of inheriting the mutation. Although inheriting a defective gene greatly increases your risk, not everyone with a mutated gene develops cancer. Types of genetically inherited colonic polyps include:
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    • Familial adenomatous polyposis (FAP) - A rare, hereditary disorder that causes the development of hundreds or thousands of polyps in the lining of the colon from teenage years.

    • Gardner's syndrome - This condition causes polyps to develop throughout the colon and small intestine and can also cause the development of noncancerous tumors in other parts of the body, including the skin (sebaceous cysts and lipomas), bones(osteomas) and abdomen (desmoids).

    • Lynch syndrome - Also known as hereditary nonpolyposis colorectal cancer (HNPCC) is the most common form of inherited colon cancer. People with Lynch syndrome tend to develop relatively few colon polyps, but those polyps can quickly become malignant. Or, people diagnosed with Lynch syndrome may develop tumors in other organs, including the breast, stomach, small intestine, urinary tract and ovaries.

    • MYH-associated polyposis (MAP) - This inherited condition is characterized by the development of multiple adenomatous polyps and colon cancer at a young age which is caused by mutations in the MYH gene.

    • Peutz-Jeghers syndrome (PJS) - This genetic condition usually begins with freckles developing all over the body, including the lips, gums and feet and is followed by the development of benign polyps develop throughout the intestines.

    • Polyposis coli – This genetic condition causes thousands of adenomatous polyps throughout the bowel.

Do doctors know what cause colonic polyps? And are you at risk of developing one? Click here to learn more about minimizing your risk for colon polyps and what causes polyps in colon.

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Tags: Colon Cancer, adenomatous polyps, polyps, adenomatous polyposis, ulcerative colitis, Crohn's Disease, large intestine, small intestine, abnormal cell, adenomatous, intestine, abdomen, anatomy, stomach, Colitis, period, breast, Cancer, affect, absorb
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Colon Polyps
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