Diagnosis

To diagnose colon cancer, a physician will ask about symptoms and medical and family history. We also use advanced diagnostic procedures and technology to effectively diagnose, inform treatment and carefully monitor the condition. Diagnostic procedures can include:

Blood tests: There is no one blood test for colon cancer, but blood tests that monitor levels of kidney and liver health over time will provide information about overall health. Blood tests can also show if a certain substance produced by some colon cancers is present.

Colonoscopy: During this procedure, a long, flexible, lighted tube with a video camera attached is inserted through the rectum to view the colon from a screen. A small amount of tissue may be removed to examine under a microscope to see if cancer is present.

Double contrast barium enema: For the procedure, an enema that contains barium, a dye for contrast, is given and air is put into the rectum before X-rays are taken of the colon. The barium allows physician to more easily see any polyps in the colon.

Causes

In most cases, the cause of colon cancer is unknown. But many lifestyle factors can lead to the development of colon cancer, including: 

• Regular, heavy use of alcohol 
• Having diabetes or being insulin resistant 
• Eating high-fat, low-fiber foods and also eating a lot of red meat 
• Having a body mass index of 30 or higher 
• A lack of exercise 
• Tobacco use 

Risk Factors

Risk factors that can contribute to colon cancer include:

Age: People older than age 45 are at greater risk for developing colon cancer.

Genetics: If family members have genetic syndromes such as Lynch syndrome or familial adenomatous polyposis, or have a family history of colon cancer, the risk increases for developing colon cancer.

History of colorectal cancer or polyps: Previously having either condition raises the risk of getting colon cancer.

Intestinal conditions: Diseases of the colon that are inflammatory and chronic, including Crohn’s disease and ulcerative colitis, can increase the risk for developing colon cancer.

Race and ethnicity: African-Americans and Ashkenazi Jews are at greater risk for developing colon cancer.

Radiation exposure: Previous radiation treatment of the abdomen can lead to colon cancer.

Prevention

While some risk factors like age and heredity cannot be controlled, there are ways you can help prevent colon cancer:

Don’t smoke: Lower the risk of getting colon cancer by not smoking.

Get screenings: People 45 and over and/or who have a family history that raises risk factors for colon cancer need routine screenings to detect colon cancer early. Screenings can include a colonoscopy and fecal occult blood test.

Limit alcohol: Reduce the risk of getting colon cancer by having only one alcoholic drink a day.

Maintain a healthy weight or lose weight: Aim for a body mass index no higher than 25 to avoid development of colon cancer. 

Practice good health: Eat a healthy low-fat diet that includes plenty of fruit and vegetables, and exercise daily.

Prognosis

The prognosis for colon cancer depends upon how early the cancer is diagnosed and the size of the tumor. The highest survival rate for colon cancer occurs for people diagnosed and treated early. Screenings can detect colon cancer in the early stages.

Treatment and Recovery

Colon cancer treatment depends upon how far the condition has progressed. It may be treated with surgery, chemotherapy, radiation or a combination of treatments. 

Surgery

The type of surgery for colon cancer can depend on the location and stage of the tumor. Options include:

• Polypectomy: During this procedure, a long tube with a video camera attached is inserted through the anus to view the colon. A tiny tool is used to remove cancerous polyps.
• Colectomy: During this procedure, the tumors and some surrounding healthy tissue are removed. Some lymph nodes are also removed for examination under a microscope to see if they are cancerous. The surgeon then reconnects parts of the colon. If it is not possible to reconnect the colon, an opening will be made to allow for elimination of waste into a colostomy bag.
• Endoscopic mucosal resection: During this procedure on a small tumor located on the surface of the colon, saltwater is injected through the wall of the colon to create a bubble underneath the tumor to remove it.

Chemotherapy

Chemotherapy uses special drugs designed to kill cancer cells. The treatments can be given as a pill or injected into the bloodstream. Chemotherapy can be administered before surgery to make the tumor smaller or after surgery to keep cancer from reoccurring. 

Radiation therapy

High-energy radiation is directed specifically to the colon to kill cancer cells. Treatments can be given before surgery to shrink tumors or after surgery to reduce the risk of cancer returning. Most often radiation treatments are given five days a week for several weeks. 

Targeted therapy

Targeted therapy can include a combination of oral and intravenous (injected into the vein) drugs or other substances, to attack the way colon cancer cells develop, multiply and interact with other cells. 

Complications

Colon cancer can return after treatment or spread to other parts of the body. Complications of colon cancer and colon cancer treatment can include:

• Intestinal obstruction 
• Nausea, vomiting or diarrhea