Colorectal cancer

Colorectal cancer includes cancerous growths in the colon, rectum, anus, and appendix. It is a major killer among the different forms of cancer.

There are different types of colon cancers, however 95% of colon cancers are Adenocarcinoma.

Most colorectal cancers are thought to arise from polyps in the colon. These mushroom-like growths are usually benign, but some may develop into cancer over time.

Table of contents

1 Risk Factors 2 Symptoms 3 Treatment 4 Prevention and Screening 5 External links

Risk Factors

The cause of colon cancer is not known but certain factors increase a person's risk of developing the disease. These include:

• Age. The risk of developing colorectal cancer increases as people get older.
• History of Cancer. Women who have had cancer of the ovary, uterus, or breast are at higher risk of developing colorectal cancer. People who have a family history of colorectal cancer also at a higher risk.
• Smoking. Smokers are more likely to die of colorectal cancer than non-smokers.
• Diet. Some studies have shown that people who have diets high in fresh fruit and vegetables and low in red meat are at reduced risk of colorectal cancer.
• Physical inactivity. People who are physically active are at lower risk of developing colorectal cancer.

Symptoms

Symptoms of colorectal cancer include

• Change in bowel habits.
• Blood in stools.
• Unexplained weight loss.
• Anemia

It is also possible that there will no symptoms at all. This is one reason why screening for the disease is recommended.

Treatment

The treatment depends on the staging of the cancer (a classification of severity based on the degree of mucosal penetration and on spread to lymph nodes or other organs). When colorectal cancer is caught at early stages (with little spread) it is likely to be curable. However when it is detected at later stages (when distant metastases are present) it it less likely to be curable.

Treatments include:

• local tumor resection
• radiation therapy
• chemotherapy (with, for example, 5-FU/LV)
• regional colon resection

Prevention and Screening

Because colorectal cancer can take many years to develop, and detecting colorectal cancer early greatly improves the chances of a cure, screening for the disease is recommended in individuals who are at increased risk. There are several different tests available for this purpose.

• Digital rectal exam (DRE): The doctor inserts a lubricated, gloved finger into the rectum to feel for abnormal areas.
• Fecal occult blood test (FOBT): A test for blood in the faeces.
• Sigmoidoscopy: A lighted probe (sigmoidoscope) is inserted into the rectum and lower colon to check for polyps and other abnormalities.*
• Colonoscopy: A lighted probe called a colonoscope is inserted into the rectum and the entire colon to look for polyps and other abnormalities that may be caused by cancer.
• Double contrast barium enema (DCBE): An enema containing barium, which helps the outline of the colon and rectum stand out on X-rays, is given to the patient. The doctor then takes a series of X-rays of the colon and rectum.

A Colonoscopy has the advantage that if polyps are found during the procedure they can be immediately removed. Tissue can also be taken for biopsy.

External links

• http://www.cancer.gov/cancerinfo/wyntk/colon-and-rectum
• Information about the condition can also be found at http://www.colorectal-cancer.net/