The Colon is the part of the Digestive System where the waste material is stored. The Rectum is the end of the Colon adjacent to the anus. Together, they form a long, muscular tube called the Large Intestine (also known as the large bowel).
Tumors of the Colon and Rectum is growths arising from the inner wall of the Large Intestine. Benign tumors of the Large Intestine are called Polyps. Malignant Tumors of the large intestine are called Cancers. Benign Polyps do not invade nearby tissue or spread to other parts of the body. Benign Polyps can be easily removed during Colonoscopy and are not life-threatening. If Benign Polyps are not removed from the Large Intestine, they can become Malignant (Cancerous) over time. Most of the cancers of the large intestine are believed to have developed from Polyps. Cancer of the Colon and Rectum (also referred to as Colorectal Cancer) can invade and damage adjacent tissues and organs. Cancer Cells can also break away and spread to other parts of the body (such as liver and lung) where new tumors form. The spread of Colon Cancer to distant organs is called Metastasis of the Colon Cancer. Once metastasis has occurred in Colorectal Cancer, a complete cure of the cancer is unlikely.
Causes of Colon Cancer
Factors that increase a person’s risk of Colorectal Cancer include
- High fat intake
- A family history of colorectal cancer and polyps
- The presence of polyps in the large intestine
- Chronic Ulcerative Colitis.
- Obesity: Obesity has been identified as a risk factor for colon cancer.
- Smoking: Cigarette smoking has been definitely linked to a higher risk for colon cancer.
Symptoms of Colon Cancer
Colon Cancer Symptoms are quite diverse and depend on where the cancer is located, where it has spread, and how big the tumor is. It is frequent for people with colon cancer to experience no symptoms in the earliest stages of the disease. However, when the cancer grows, symptoms include:
- Diarrhea or constipation
- Changes in stool consistency
- Narrow stools
- Rectal bleeding or blood in the stool
- Pain, cramps, or gas in the abdomen
- Pain during bowel movements
- Continual urges to defecate
- Weakness or fatigue
- Unexplained weight loss
- Irritable bowel syndrome (IBS)
- Iron deficiency (anemia)
If the cancer spreads, or metastasizes, additional symptoms can present themselves in the newly affected area.
Prevention of Colon Cancer
People with an average risk of colon cancer can consider screening beginning at age 50. But people with an increased risk, such as those with a family history of colon cancer, should consider screening sooner. Options may include:
- Annual fecal occult blood testing
- Flexible sigmoidoscopy every five years
- Colonoscopy every 10 years
- Virtual colonoscopy (CT colonography) every five years
- Stool DNA testing — though this is a new screening approach and it’s not clear how often it should be repeated
Change Life Style. Take following steps to change your life style:
- Eat a variety of fruits, vegetables and whole grains. Fruits, vegetables and whole grains contain vitamins, minerals, fiber and antioxidants, which may play a role in cancer prevention. Choose a variety of fruits and vegetables so that you get an array of vitamins and nutrients.
- Drink alcohol in moderation. If you choose to drink alcohol, limit the amount of alcohol you drink to no more than one drink a day for women and two for men.
- Stop smoking. Talk to your doctor about ways to quit that may work for you.
- Exercise most days of the week. Try to get at least 30 minutes of exercise on most days. If you’ve been inactive, start slowly and build up gradually to 30 minutes. Also, talk to your doctor before starting any exercise program.
- Maintain a healthy weight. If you have a healthy weight, work to maintain your weight by combining a healthy diet with daily exercise.
If you have an increased risk of colon cancer, discuss the benefits and risks of these preventive treatments with your doctor:
- Aspirin. Some evidence links a reduced risk of polyps and colon cancer to regular aspirin use. However, studies of low-dose aspirin or short-term use of aspirin haven’t found this to be true. It’s likely that you may be able to reduce your risk of colon cancer by taking large doses of aspirin over a long period of time. But using aspirin in this way carries a risk of side effects, such as gastrointestinal bleeding and ulcers.
- Other pain relievers. Other pain relievers, such as ibuprofen (Advil, Motrin, others) and naproxen (Aleve, others), have also been studied as a way to prevent colon cancer. Some studies have found these other pain relievers may reduce the risk of precancerous polyps and colon cancer. But side effects include ulcers and gastrointestinal bleeding. Some of these other pain relievers have been linked to an increased risk of heart problems.
- Celecoxib (Celebrex). Celecoxib and other drugs known as COX-2 inhibitors provide pain relief. Some evidence suggests COX-2 drugs can reduce the risk of precancerous polyps in people who’ve been diagnosed with these polyps in the past. But COX-2 drugs carry a risk of heart problems, including heart attack. Two COX-2 inhibitor drugs were removed from the market because of these risks.
- Surgery to prevent cancer. In cases of rare, inherited syndromes such as familial adenomatous polyposis, or inflammatory bowel disease such as ulcerative colitis, your doctor may recommend removal of your entire colon and rectum in order to prevent cancer from occurring.
Treatment of Colon Cancer
Treatment depends on many things, including the stage of the cancer. In general, treatments may include:
- Surgery (most often a Colectomy) to remove cancer cells
- Chemotherapy to kill cancer cells
- Radiation Therapy to destroy cancerous tissue
Colon Cancer Diet
- Eat less total fat. Limit your daily fat intake to no more than 20 percent of your total food calories.
- Increase Your Fiber Intake. In all the research between food and cancer, the evidence for a relationship between a high fiber diet and lower chances of colorectal cancer is the most conclusive.
- Eat lots of raw fruits and vegetables. The consensus of the hundreds of studies exploring the link between diet and cancer is that eating more fruits and vegetables reduces the risk of all types of cancers.
- Switch from red meat to seafood. Populations who eat the most red meat and fat in their diet have the highest incidence of colon cancer.
- Switch from an animal-based diet to a plant-based diet. One of the theories on the high incidence of cancer in modern times is the belief that the switch from plant based to animal based diets correlates with the increase in cancer.
- Eat more soy products. Soy is a more healthful source of protein than meat. The primary anti- cancer value of soy seems to come from phytonutrients (for example, isoflavones) which inhibit the growth of new blood vessels necessary for tumor survival. Soy also protects against colon cancer by blocking the carcinogenic effects of bile acids (a process called angiogenesis).
- Change your oils. Oils that are rich in omega-3 fatty acids (i.e., fish and flax oils) have anti-cancer properties.
- Eat foods containing calcium. Studies have shown that populations with a high intake of calcium (e.g., people in Sweden) have a lower incidence of colorectal cancer.
- Eat a diet high in antioxidants. While there are many unsubstantiated claims about the benefits of antioxidants, there is reliable scientific evidence that beta carotene, vitamin C and vitamin E definitely lower the risk of colorectal cancer.
- Drink less alcohol.
- Eat other anti-cancer nutrients. Increasing several other daily nutrients can also lower your risk of cancer.
- Flaxseeds contain two cancer-preventive compounds: omega 3 fatty acids and lignans, which may reduce the risk of breast cancer and colon cancer.
Survival Rates for Colon Cancer by stage
|Stage||5-year Survival Rate|
*In this study, survival was better for some stage IIIA than for some stage IIB. The reasons for this are not clear.
|Colon Cancer Signs||Tumors of the Colon and Rectum||Benign Polyps,|
|Colonoscopy||Large Intestine||Colorectal Cancer|
|Causes of Colon Cancer||Colon Cancer View||Symptoms of Colon Cancer|
|Prevention of Colon Cancer||preventive treatments||Treatment of Colon Cancer|
|Colon Cancer Foods||Survival Rates for Colon Cancer by stage|
- Aspirin and Colon Cancer (nlm.nih.gov)
- Simpler Colon Screen May Be Enough for Many Women (nlm.nih.gov)
- Aspirin may be big help against some colon cancer, major study shows (cbsnews.com)