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Colorectal cancer

Also listed as: Cancer - colorectal


Colorectal cancer -- cancer of the colon and rectum -- is the second most commonly diagnosed cancer in American men and women. Colorectal cancer develops in the digestive system, which processes food for energy and rids the body of solid waste. Together, the colon and rectum form a muscular tube about 5 feet long known as the large intestine. The colon (the first and largest part of the large intestine) absorbs water and nutrients from food and serves as a storage place for solid waste. The waste moves from the colon into the rectum (the final 6 inches of the large intestine) where it passes out of the body through the anus. Cancers affecting either of these organs are called colorectal cancer. Most colorectal cancers arise from benign polyps (abnormal masses of tissue) that begin growing on the inner lining of the colon or rectum. These growths spread very slowly, taking from 10 - 20 years to become cancerous. Once colorectal cancer is diagnosed, the prognosis depends on how far the cancer has spread.

The American Cancer Society estimates that about 150,000 cases of colorectal cancer are diagnosed every year in the United States. Most cases of colorectal cancer occur in people older than 50 years of age. Although colorectal cancer is expected to be responsible for about 56,000 deaths this year, the death rate from this form of cancer has been dropping steadily for the past 15 years. Some researchers speculate that the lowering death rate is due to prevention and early treatment of the disease.


Signs and Symptoms

Unfortunately, most people with colorectal cancer will not begin to experience symptoms until the disease is already at a late stage. In fact, some people may experience no symptoms at all. This is the reason that screening tests, such as a colonoscopy, are so important.

In general, signs and symptoms of colorectal cancer can include the following:

These symptoms may be caused by colorectal cancer or by other conditions such as infections, hemorrhoids, and inflammatory bowel disease. It is important to bring any of these symptoms to the attention of your health care provider to determine the cause of your symptoms.


Causes

Although more than half of all colorectal cancers occur without any clear cause, studies suggest that genetic factors may play an important role in the development of the disease. For example, many people with colorectal cancer carry specific genetic mutations (genes that normally suppress cancer growth are mutated and actually promote cancer growth) or have relatives with the condition. Those with a family history of specific genetic syndromes -- such as familial adenomatous polyposis, Lynch syndrome, juvenile polyposis, and Peutz-Jeghers syndrome -- are also at an increased risk for developing colorectal cancer. Dietary and lifestyle factors, such as smoking and high-fat intake, also influence the development of colorectal cancer. Some researchers speculate that genetic factors predispose a person to colorectal cancer, but that dietary and lifestyle factors play a strong role in determining which "at-risk" individuals go on to develop the disease.


Risk Factors


Diagnosis

After obtaining a complete medical history, a health care provider will perform a physical exam and may order one or more tests to diagnose colorectal cancer. As mentioned in the Preventive Care section, standard tests used to diagnose colorectal cancer include the sigmoidoscopy, colonoscopy, and barium enema. At the time of either a sigmoidoscopy or a colonscopy, a biopsy (sample of tissue) is removed from the colon or rectum and examined under a microscope in order to detect abnormal growths. If the doctor finds cancer, a series of tests (chest x-ray, abdominal CT scan, and blood tests to check liver function) will be performed to determine if the cancer has spread and to help determine the stage (or extent) of the disease. Stages of colorectal cancer include:


Preventive Care

Screening

Colorectal cancer is highly preventable, even curable, when detected early. Regular screening for colorectal cancer helps detect the presence of polyps before they become cancerous. The American Cancer Society recommends the following standard screening practices for individuals who are not at high risk for colorectal cancer and who have no symptoms of the disease:

Those with a family history of colorectal cancer should undergo colonoscopy every 3 - 5 years, starting at least 10 years before the age of the relative at the time of his or her diagnosis. Those with a family history of familial adenomatous polyposis (a condition causing thousands of polyps along the inner lining of the colon) or other similar genetic syndromes (listed under Causes) should start having colonoscopies at age 10.

Diet and Exercise

People may also lower their chances of developing colorectal cancer by managing the risk factors they can control, such as diet and exercise. For example, eating plenty of fruits and vegetables as well as foods rich in omega-3 fatty acids (such as salmon and halibut) and calcium (such as sea vegetables and kale) can help reduce the risk of colorectal cancer. Limiting alcohol consumption, quitting smoking, and reducing the intake of high-fat and fried foods, particularly red meats, may also protect developing colorectal cancer.

Physical activity also will decrease the risk factors associated with developing colorectal cancer. Obesity and a sedentary lifestyle increases the risk of colorectal cancer. Even small amounts of exercise on a regular basis can be helpful, and the American Cancer Society recommends at least 30 minutes of physical activity on most days.

Other Preventive Measures

Preliminary studies also suggest that aspirin may prevent tumor growth and that hormone replacement therapy (HRT) may reduce the risk of colorectal cancer in women. However, HRT may increase the chances of developing other cancers, such as breast and ovarian. It is recommended to choose diet and lifestyle changes along with dietary supplements to protect against the risk factors associated with colorectal cancer.


Treatment

Surgery to remove the tumor is the only way to cure the disease, and early detection is the best preparation for successful treatment. Depending on the stage of the cancer, surgery is generally followed with chemotherapy. If the tumor is particularly large, radiation may be necessary before or after surgery.

Certain medications or supplements may help prevent the development of polyps and/or colorectal cancer. Modifying lifestyle, particularly avoiding red meat, losing weight, quitting smoking, and increasing physical activity, may help prevent the disease -- even in individuals with a family history of the condition.

Lifestyle

An unhealthy lifestyle may increase the risk of colorectal cancer even in people who have no family history of the condition. Some experts believe that adjusting lifestyle habits may decrease the likelihood of developing colorectal cancer by as much as 70% in some individuals.

Findings from studies support the association between colorectal cancer and physical inactivity and obesity. Research continues to point to the idea that exercise and low-calorie diets can help to prevent colorectal cancer.

A large, population-based study of men and women in Hawaii found that the following lifestyle factors were linked with colorectal cancer:

Medications

After surgery, chemotherapy (the use of anticancer drugs to destroy cancer cells) may be given to kill any cancerous cells that remain in the body. Chemotherapy controls the spread of the disease and improves survival rates over time. The following chemotherapeutic medications are used alone or in combination to treat colorectal cancer:

For colorectal cancer that has metastasized, or spread, doctors generally use 5-FU in combination with other drugs. One regimen approved by the United States Food and Drug Administration for metastatic colorectal cancer is 5-FU, leucovorin, and irinotecan. With the addition of irinotecan, the progression of the disease significantly slowed and survival improved compared to the 5-FU-leucovorin combination. However, an unexpectedly high death rate in two recent studies by the National Cancer Institute has brought the addition of irinotecan into question. There are other medications currently under investigation for metastatic colon cancer.

Long-term use of aspirin, other nonsteroidal anti-inflammatory drugs (NSAIDs), and hormone replacement therapy have shown promise in the prevention and treatment of colorectal cancer.

Surgery and Other Procedures

Surgery is the treatment of choice for colorectal cancer, and is best when the disease is detected at an early stage. Before becoming cancerous, polyps can be removed during a colonoscopy. Depending on the severity and location of the cancer, including whether or where it has spread, an individual may need a partial or total removal of the colon (colectomy) and rectum (rectal resection). During surgery, the surgeon also examines other abdominal organs for signs of cancer. If cancer has spread to the liver, a portion of this organ may be removed as well. After removing the tumor and nearby tissue, the surgeon reconnects the healthy portions of the colon or rectum. If the healthy portions of the colon or rectum cannot be reconnected, a temporary or permanent opening (stoma) is made through the wall of the abdomen into the colon to provide a new path for waste material to leave the body. This procedure is called a colostomy. Radiation may also be used before or during surgery (called intraoperative radiotherapy) to shrink the tumor, and it may be recommended following surgery for certain stages of colorectal cancer to reduce the risk of recurrence. Following surgery, colonoscopies are performed every 3 - 6 months for 3 years to detect recurrence.

Nutrition and Dietary Supplements

A comprehensive treatment plan for colorectal cancer may include a range of complementary and alternative therapies. Nutrients and herbs may protect against side effects from conventional therapies as well as enhance chemotherapy and support anticancer activities. Mind-body therapies such as meditation, relaxation techniques, yoga, and qi gong may reduce the effects of stress and enhance your quality of life and your response to treatment. Ask your team of health care providers about the best ways to incorporate these therapies into your overall treatment plan.

Always tell your health care provider about the herbs and supplements you are using or considering, as some supplements may interfere with conventional cancer treatments.

Following these nutritional tips may help reduce symptoms:

You may use nutritional deficiencies with the following supplements:

Herbs

Herbs are generally a safe way to strengthen and tone the body's systems. As with any therapy, you should work with your health care provider to get your problem diagnosed before starting any treatment. You may use herbs as dried extracts (capsules, powders, teas), glycerites (glycerine extracts), or tinctures (alcohol extracts). Unless otherwise indicated, you should make teas with 1 tsp. herb per cup of hot water. Steep covered 5 - 10 minutes for leaf or flowers, and 10 - 20 minutes for roots. Drink 2 - 4 cups per day. You may use tinctures alone or in combination as noted.

Acupuncture

While acupuncture is not used as a treatment for cancer itself, evidence suggests it can be a valuable therapy for cancer-related symptoms (particularly nausea and vomiting that often accompanies chemotherapy treatment). Studies have indicatedthat acupuncture may help reduce pain and shortness of breath. Acupressure (pressing on rather than needling acupuncture points) has also proved useful in controlling breathlessness. Patients can learn this technique and use to treat themselves.

Some acupuncturists prefer to work with a patient only after the completion of conventional medical cancer therapy. Others will provide acupuncture or herbal therapy during active chemotherapy or radiation. Acupuncturists treat cancer patients based on an individualized assessment of the excesses and deficiencies of qi located in various meridians. In many cases of cancer-related symptoms, a qi deficiency is usually detected in the spleen or kidney meridians.

Mind-Body Medicine

Relaxation techniques are beneficial for individuals undergoing surgery. In one study it was observed that patients who received standard care plus relaxation techniques in the form of guided imagery audiotapes before, during, and after surgery experienced significantly better sleep and less pain following the surgery than patients who received only standard care.


Other Considerations

Pregnancy

Colorectal cancer may be detected late in pregnant women because symptoms of the disease, such as rectal bleeding, nausea, and vomiting, resemble the symptoms of pregnancy. Pregnant women should avoid chemotherapy and radiation therapy. Surgery puts the fetus at risk, therefore folic acid and nutritional needs are usually maintained during pregnancy, and treatment is postponed until after the baby is delivered.

Prognosis and Complications

Follow-up care after treatment for colorectal cancer is very important. If the cancer returns or if new cancer develops, it should be treated as soon as possible. If left untreated, colorectal cancer can spread to the liver or lungs, or a tumor may block the colon. In some cases, individuals with colorectal cancer may need to have their entire colon or rectum removed. If the surgeon cannot reconnect healthy portions of the colon or rectum, a temporary or permanent surgical opening (stoma) is made through the wall of the abdomen into the colon to provide a new path for waste material to leave the body. After this procedure, a special bag is worn to collect body waste. Individuals who wear the bag may need counseling on how to care for the stoma as well as how to deal with the emotional difficulties associated with this procedure.

The outlook in cases of colorectal cancer depends on how deeply the tumor has penetrated into the tissue and whether the cancer has spread to lymph nodes in the abdominal region or to other areas of the body. Following are the proportions of individuals who survive at least 5 years based on the stage of their disease when it was first diagnosed:


Supporting Research

Albanes D, Malila N, Taylor PR, et al. Effects of supplemental a-tocopherol and ß-carotene on colorectal cancer: results from a controlled trial (Finland). Cancer Causes Control . 2000;11:197-205.

Alimi D, Rubino C, Leandri EP, Brule SF. Analgesic effects of auricular acupuncture for cancer pain [letter]. J Pain Symptom Manage. 2000;19(2):81-82.

Anti M, Armelau F, Marra G, et al. Effects of different doses of fish oil on rectal cell proliferation in patients with sporadic colonic adenomas. Gastroenterology. 1994;107(6):1892-1894.

Baron JA, Beach M, Mandel JS, et al. Calcium supplements for the prevention of colorectal adenomas. N Eng J Med. 1999;340:101-107.

Bast A, Haenen GR. Lipoic acid: a multifunctional antioxidant. Biofactors. 2003;17(1-4):207-13.

Bauer JD, Capra S. Nutrition intervention improves outcomes in patients with cancer cachexia receiving chemotherapy -- a pilot study. Support Care Cancer. 2005;13(4):270-4.

Baur JA, Sinclair DA. Therapeutic potential of resveratrol: the in vivo evidence. Nat Rev Drug Discov. 2006;5(6):493-506.

Biasco G, Zannoni U, Paganelli GM, et al. Folic acid supplementation and cell kinetics of rectal mucosa in patients with ulcerative colitis. Cancer Epidemiol Biomarkers Prev . 1997;6:469-471.

Birdsall TC. The biological effects and clinical uses of the pineal hormone melatonin. Alt Med Rev. 1996; 1(2):94-102.

Bonithon-Kopp C, Kronborg O, Giacosa A, Rath U, Faivre J. Calcium and fibre supplementation in prevention of colorectal adenoma recurrence: a randomised intervention trial. European Cancer Prevention Organisation Study Group. Lancet . 2000;356:1300-1306.

Bushman JL. Green tea and cancer in humans: a review of the literature. Nutr Cancer . 1998;31(3):151-159.

Davies MJ, Bowey EA, Adlercreutz H, Rowland IR, Rumsby PC. Effects of soy or rye supplementation of high-fat diets on colon tumour development in azoxymethane treated rats. Carcinogenesis. 1999;20(6):927-931.

de Deckere EAM. Possible beneficial effect of fish and fish n -3 polyunsaturated fatty acids in breast and colorectal cancer. Euro J Cancer Prev . 1999;8:213-221.

Doron S, Gorbach SL. Probiotics: their role in the treatment and prevention of disease. Expert Rev Anti Infect Ther. 2006;4(2):261-75.

Douillard JY, Cunningham D, Roth AD, Navarro M, James RD, Karasek P, et al. Irinotecan combined with fluorouracil compared with fluorouracil alone as first-line treatment for metastatic colorectal cancer: a multicentre randomised trial. Lancet. 2000;355:1041-1047.

Ezzo J, Berman B, Hadhazy VA, Jadad AR, Lao L, Singh BB. Is acupuncture effective for the treatment of chronic pain? A systematic review. Pain . 2000;86:217-225.

Filshie J, Penn K, Ashley S, Davis CL. Acupuncture for the relief of cancer-related breathlessness. Palliat Med. 1998;10:145-150.

Flood A, Schatzkin A. Colorectal cancer: does it matter if you eat your fruits and vegetables? J Natl Cancer Inst . 2000;92(21):1706-1707.

Giacosa A, Frascio F, Sukkar SG, Roncella S. Food intake and body composition in cancer cachexia. Nutrition. 1996;12:S20-S23.

Giardiello FM, Offerhause GJ, DuBois RN. The role of nonsteroidal anti-inflammatory drugs in colorectal cancer prevention. Eur J Cancer. 1995;31A(7-8):1071-1076.

Giovannucci E, Colditsz GA, Stampfer MJ, Willett WC. Physical activity, obesity, and risk of colorectal adenoma in women (United States). Cancer Causes Control. 1996;7:253-263.

Giovannucci E, Rimm EB, Stampfer MJ, et al. Aspirin use and the risk for colorectal cancer and adenoma in male health professionals. Ann Intern Med . 1994a;121(4):241-246.

Greenberg ER, Baron JA, Tosteson TD, et al. A clinical trial of antioxidant vitamins to prevent colorectal adenoma. N Engl J Med. 1994;331:141-147.

Holt PR. Dairy foods and prevention of colon cancer: human studies. J Am Coll Nutr . 1999;18(suppl 5):379S-391S.

Jänne PA, Mayer RJ. Chemoprevention of colorectal cancer. N Engl J Med . 2000;342(26):1960-1968.

Kawamori T, Lubet R, Steele VE, et al. Chemopreventive effect of curcumin, a naturally occurring anti-inflammatory agent, during the promotion/progression stages of colon cancer. Cancer Res. 1999;59:597-601.

Kodama N, Komuta K, Nanba H. Effect of Maitake (Grifola frondosa) D-Fraction on the activation of NK cells in cancer patients. J Med Food . 2003;6(4):371-7.

LaValle JB, Krinsky DL, Hawkins EB, et al. Natural Therapeutics Pocket Guide. Hudson, OH:LexiComp; 2000: 452-454.

La Vecchia C, Braga C, Negri E, et al. Intake of selected micronutrients and risk of colorectal cancer. Int J Cancer . 1997;73:525-530.

Le Marchand L, Wilkens LR, Hankin JH, Kolonel LN, Lyu LC. Independent and joint effects of family history and lifestyle on colorectal cancer risk: Implications for prevention. Cancer Epidemiol Biomarkers Prevent. 1999;8:45-51.

Le Marchand L, Hankin JH, Wilkens LR, Kolonel LN, Englyst HN, Lyu L. Dietary fiber and colorectal cancer risk. Epidemiology . 1997a;8:658-665.

Le Marchand L, Wilkens LR, Kolonel LN, Hankin JH, Lyu LC. Associations of sedentary lifestyle, obesity, smoking, alcohol use, and diabetes with the risk of colorectal cancer. Cancer Res. 1997b;57:4787-4794.

Maa SH, Gauthier D, Turner M. Acupressure as an adjunct to a pulmonary rehabilitation program. J Cardiopulm Rehabil . 1997;17(4):268-276.

Mayer RJ. Gastrointestinal tract cancer. In: Fauci AS, Braunwald E, Isselbacher KJ, et al, eds. Harrison's Principles of Internal Medicine . 14th ed. New York, NY: McGraw-Hill; 1998:571-576.

Messina M, Bennink M. Soy foods, isoflavones and risk of colonic cancer: A review of the in vitro and in vivo data. Bailliéres Clin Endocrinol Metab . 1998:12(4):707-728.

Michels KB, Giovannucci E, Joshipura KJ, et al. Prospective study of fruit and vegetable consumption and incidence of colon and rectal cancers. J Natl Cancer Inst . 2000;92:1740-1752.

Narisawa T, Fukaura Y, Hasebe M, et al. Prevention of N-methylnitrosourea-induced colon carcinogenesis in F344 rats by lycopene and tomato juice rich in lycopene. Jpn J Cancer Res . 1998;89:1003-1008.

Owen RW, Giacosa A, Hull WE, Haubner R, Spiegelhalder B, Bartsch H. The antioxidant/anticancer potential of phenolic compounds isolated from olive oil. Eur J Cancer. 2000a;36(10):1235-1247.

Pan CX, Morrison RS, Ness J, Fugh-Berman A, Leipzig RM. Complementary and alternative medicine in the management of pain, dyspnea, and nausea and vomiting near the end of life: a systematic review. J Pain Symptom Manage. 2000;20(5):374-387.

Piazza GA, Alberts DS, Hixson LJ, et al. Sulindac sulfone inhibits azoxymethane-induced colon carcinogenesis in rats without reducing prostaglandin levels. Cancer Res. 1997;57(14):2909-2915.

Potter JD. Nutrition and colorectal cancer. Cancer Causes Control . 1996;7:127-146.

Rao CV, Rivenson A, Simi B, et al. Chemoprevention of colon carcinogenesis by sulindac, a nonsteroidal anti-inflammatory agent. Cancer Res. 1995;55(7):1464-1472.

Renzi C, Peticca L, Pescatori M. The use of relaxation techniques in the perioperative management of proctological patients: preliminary results. Int J Colorectal Dis. 2000;15(5-6):313-316.

Schatzkin A, Lanza E, Corle D, et al. Lack of effect of a low-fat, high-fiber diet on the recurrence of colorectal adenomas. NEJM . 2000;342(16):1149-1155.

Shen J, Wenger N, Glaspy J, et al. Electroacupuncture for control of myeloablative chemotherapy-induced emesis. JAMA. 2000;284(21):2755-2761.

Simopoulos AP. Essential fatty acids in health and chronic disease. Am J Clin Nutr. 1999;70(3 suppl):560S-569S.

Slattery ML, Benson J, Curtin K, Ma K-N, Schaeffer D, Potter JD. Carotenoids and colon cancer. Am J Clin Nutr . 2000;71:575-582.

Sung MK, Lautens M, Thompson LU. Mammalian lignans inhibit the growth of estrogen-independent human colon tumor cells. Anticancer Res. 1998;18(3A):1405-1408.

Thiagarajan D, Bennink MR, Bourquin LD, Kavas FA. Prevention of precancerous colonic lesions in rats by soy flakes, soy flour, genistein, and calcium. Am J Clin Nutr. 1998;68(suppl):1394S-1399S.

Turowski GA, Rashid Z, Hong F, Madri J, Basson MD. Glutamine modulates phenotype and stimulates proliferation in human colon cancer cell lines. Cancer Res . 1994;54:5974-5980.

Vickers AJ. Can acupuncture have specific effects on health? A systematic review of acupuncture antiemesis trials. J R Soc Med. 1996;89:303-311.


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