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.

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:

• Changes in bowel habits
• Blood in the stool
• Problems related to blood loss (anemia, weakness, fatigue, shortness of breath, pounding or racing heart, chest pain, and intolerance to exercise)
• Abdominal discomfort (frequent gas, bloating, fullness, cramps, and pain)
• Unexplained weight loss
• Pain with defecation
• Stools that are narrower than usual
• Urgent desire to defecate (and the passage of little matter)

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.

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.

• Family history of colorectal cancer or polyps in the colon
• Older age (over 50 years)
• Living in an industrialized country like the United States
• Polyps on the inner lining of the colon or rectum
• African-American descent
• Diets high in meat and low in fruits and vegetables
• Overweight or obesity
• Regular consumption of alcohol
• Smoking cigarettes regularly
• Inflammatory bowel disease (such as irritable bowel syndrome, Crohn's disease, and ulcerative colitis)

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:

• Stage A: The earliest stage; cancer is found only in the innermost lining of the colon and/or rectum.
• Stage B1: Involves the muscular part of the colon and/or rectum.
• Stage B2: Cancer has spread to deeper layers of the wall of the colon and/or rectum.
• Stage C: Cancer has spread to nearby lymph nodes but not to other parts of the body.
• Stage D: Cancer has spread to other parts of the body, such as the liver and lungs.

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:

• Annual digital rectal exams starting at age 40: The doctor inserts a lubricated, gloved finger into the rectum to feel for abnormal areas.
• Annual fecal occult blood tests starting at age 50: Stool samples are tested in the doctor's office for the presence of hidden blood.
• Visualization of the colon via one of the following:
  • Sigmoidoscopy (examination of the rectum and lower colon using a lighted instrument)
  • Colonoscopy (examination of the rectum and entire colon using a lighted instrument)
  • Barium enema (examination using a series of x-rays that reveal barium-stained outlines of the colon and rectum) every 3 -5 years starting at age 50

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.

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:

• Smoking
• Alcohol consumption
• History of diabetes
• Frequent constipation
• High-calorie diet
• Obesity
• Physical inactivity
• Low vegetable fiber intake (this association is controversial)
• High levels of insulin (hormone that controls blood sugar levels)
• Meat consumption

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:

• Fluorouracil (5-FU) -- often used in combination with leucovorin for 6 months after surgery. Reduces the rate of recurrence and improves chances of survival. Common side effects include nausea, diarrhea, inflammation of the skin and lining of the mouth, and lowered white blood cell count, which increases the chance of developing an infection and anemia.
• Leucovorin -- a form of folic acid often used in combination with 5-FU. Side effects are rare but can include rash, itching, and wheezing.
• Levamisole -- can be used in combination with 5-FU. Potential side effects are numerous and include nausea, vomiting, diarrhea, loss of appetite, abdominal pain, lower extremity swelling, insomnia, fatigue, headache, hair loss, dizziness, muscle and joint paints, and depression.

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.

• Aspirin -- may reduce the risk of polyps and colorectal cancer by up to 44%.
• NSAIDs -- reduced the number of polyps by 90% and colon tumors by 55% in animals.
• Hormone-replacement therapy (HRT) -- over the past 20 years, the rate of death from colorectal cancer among women has decreased far more than the rate among men. Studies suggest that this may be due to the increasing use of hormone-replacement therapy by women after menopause. However, HRT is not without risks, and your health care provider will help you determine which treatment is best for you.

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:

• Try to eliminate potential food allergens, including dairy, wheat (gluten), corn, preservatives, and food additives. Your health care provider may want to test for food sensitivities.
• Eat antioxidant foods, including fruits (such as blueberries, cherries, and tomatoes), and vegetables (such as squash and bell peppers).
• Eat foods high in B-vitamins and calcium, such as almonds, beans, whole grains (if no allergy), dark leafy greens (such as spinach and kale), and sea vegetables.
• Avoid refined foods such as white breads, pastas, and especially sugar.
• Eat fewer red meats and more lean meats, cold-water fish, tofu (soy, if no allergy) or beans for protein. Quality protein sources, such as organic meat and eggs, whey, and vegetable protein shakes, should be used as part of balanced program aimed at gaining muscle mass and preventing wasting that can sometimes be side effects of cancer therapies.
• Use healthy oils, such as olive oil or vegetable oil.
• Reduce or eliminate trans-fatty acids, found in commercially baked goods such as cookies, crackers, cakes, French fries, onion rings, donuts, processed foods, and margarine.
• Avoid coffee and other stimulants, alcohol, and tobacco.
• Drink 6 - 8 glasses of filtered water daily.
• Exercise at least 30 minutes daily, 5 days a week.

You may use nutritional deficiencies with the following supplements:

• A multivitamin daily, containing the antioxidant vitamins A, C, E, the B-complex vitamins, and trace minerals such as magnesium, calcium, zinc, and selenium.
• Omega-3 fatty acids, such as fish oil, 1 - 2 capsules or 1 - 3 tablespoonfuls oil daily, to help decrease inflammation and help with immunity. Cold-water fish, such as salmon or halibut, are good sources.
• Vitamin C, 500 - 1,000 mg, one to three times daily, as an antioxidant and for immune support.
• L-glutamine, 500 - 1,000 mg three times daily, for support of gastrointestinal health and immunity.
• Probiotic supplement (containing Lactobacillus acidophilus), 5 - 10 billion CFUs (colony forming units) a day, when needed for maintenance of gastrointestinal and immune health. You should refrigerate your probiotic supplements for best results.
• Grapefruit seed extract (Citrus paradisi), 100 mg capsule or 5 - 10 drops (in favorite beverage) three times daily when needed, for antibacterial, antifungal, and antiviral activity, and for immunity.
• Astaxanthin, 2 - 6 mg daily, for immune and antioxidant support.
• Alpha-lipoic acid, 25 - 50 mg twice daily, for antioxidant support.
• Resveratrol (from red wine), 50 - 200 mg daily, to help decrease inflammation and for antioxidant effects.
• Coenzyme Q10, 100 - 200 mg at bedtime, for antioxidant and immune activity.
• Melatonin, 2 - 6 mg at bedtime as needed, for immune support and sleep. Higher doses may be needed in cancer. Consult your health care provider.

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.

• Green tea (Camellia sinensis) standardized extract, 250 - 500 mg daily, for antioxidant, anticancer and immune effects. Use caffeine-free products. You may also prepare teas from the leaf of this herb.
• Reishi mushroom (Ganoderma lucidum) standardized extract, 150 - 300 mg two to three times daily, for anticancer and immune effects. You may also take a tincture of this mushroom extract, 30 - 60 drops two to three times a day.
• Maitake mushroom (Grifola frondosa) standardized extract (D-fraction), 600 mg twice daily, for immune and anticancer effects. You may also take a tincture of this mushroom extract, 30 - 60 drops two to three times a day.
• Olive leaf (Olea europaea) standardized extract, 250 - 500 mg one to three times daily, for anticancer and immune effects.
• Turmeric (Curcuma longa) standardized extract, 300 mg three times a day, for pain and inflammation.
• Milk thistle (Silybum marianum) seed standardized extract, 80 - 160 mg two to three times daily, for detoxification support.
• Fermented wheat germ extract, 1 packet dissolved in favorite beverage once daily, for anticancer and immune effects.

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.

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:

• Stage A -- more than 90%
• Stages B1 and B2 -- 85%
• Stage C -- 70% to 80%
• Stage D -- 5%

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