This week was very sobering. I met a very young lady who was being evaluated for the recent onset of abdominal pain that was progressing in severity without explanation. An abdominal ultrasound discovered a large abdominal mass and subsequent testing confirmed that she had colon cancer, which had already spread to her liver. She did not have a family history or other obvious risk factors for colorectal cancer, a disease that can strike without warning.
March is Colorectal Cancer Awareness Month, which gives me an excellent opportunity to remind you about the importance of prevention, as well as of colonoscopy, a test that can literally save your life.
Colorectal cancer (also called colon cancer or large bowel cancer) is the growth of cancerous cells in the colon, rectum and the appendix. It is the most common cancer of the digestive organs, accounting for more than 50 percent of all cases of cancer in the digestive tract. Cancers of the digestive system account for almost 25 percent of annual cancer fatalities in the United States.
Who is at risk for colorectal cancer? The following factors play a role:
- Age. Colorectal cancer affects both men and women of all races and ethnicities. The risk of colorectal cancer begins at increase at age 40 but the disease is typically found in people age 50 or older. In fact, 90 percent of those who develop colorectal cancer are over the age of 50.
- Race. African Americans have a greater risk of colorectal cancer than do people of other races.
- Personal or family history of colorectal cancer and adenomatous polyposis of the colon. Approximately 25 percent of all colorectal cancers have a genetic component, while about 75 percent of cases are sporadic, or non-inherited.
- Personal history of inflammatory bowel disease. Both Crohn's disease of the colon and ulcerative colitis increase the risk of developing colorectal cancer.
- Genetic colorectal cancer syndromes. These syndromes include familial adenomatous polyposis (1 to 2 percent of cases) and hereditary nonpolyposis colorectal cancer (3 to 5 percent), which is also known as Lynch syndrome. People who have an inheritable syndrome develop colorectal cancer at a much younger age than the general population.
- Radiation therapy for cancer. While there currently isn't conclusive evidence proving this potential risk factor, some previous studies have suggested that radiation therapy directed at the abdomen to treat other cancers may increase the risk of colorectal cancer.
While colorectal cancer is the third most common cancer in Europe and the United States, it is considered rare in both Africa and Asia (barring Westernized Japan). Why is it more common in the West? Diet and lifestyle differences play an important role. There are seven behavioral risk factors that have been consistently correlated with an increase in colorectal cancer. These are:
- Low physical activity
- Low fruit and vegetable intake
- High caloric intake from fat
- High alcohol intake
- High intake of red and processed meat
Prevention is Key
Fortunately, there's much you can do to prevent colorectal cancer. Good nutrition and physical activity play an important role in preventing colorectal cancer. Aim for at least 30 to 45 minutes of moderate-to-vigorous activity on most days of the week. The following nutritional factors have also been shown to help prevent colorectal cancer:
- Increase your fruit and vegetable intake. Favor cruciferous vegetables such as broccoli and cauliflower. Cruciferous vegetables are high in fiber and contain chemicals such as indole 3-carbinol and crambene that rev up our detoxification system while protecting our cells against the damaging effects of oxygen free radicals. Fruits and vegetables contain cancer-fighting phytochemicals and vitamins.
- Lower your intake of red and processed meats, and consider increasing your intake of fish. Women who eat at least three servings of fish per week have been found to be at lower risk for developing precancerous adenomatous polyps of the colon.
- Consider using soy as a protein source. Soy isoflavones have many biological properties that appear to protect against colorectal cancer.
- Supplement with calcium. Researchers have found that increased consumption of calcium in women is related to a lower risk of colorectal cancer and recurrent colorectal adenomas.
- Maintain adequate levels of vitamin D. Studies have shown that inadequate levels (25 hydroxyvitamin D< 25 ng/mL) of vitamin D place you at a higher risk for developing colorectal cancer, while adequate levels are protective. Have your doctor check your vitamin D levels. Exposure to sunlight, milk products, salmon and vitamin supplements can all help boost vitamin D.
- Consider a multivitamin/multi-mineral supplement. Vitamins such as A, B6, C, E and folic acid (no more than 400 micrograms), as well as the mineral selenium, have been shown to protect against colorectal cancer.
- Fiber up! Multiple studies show that a diet abundant in fiber protects against colorectal cancer. Eating three servings of whole grains per day has found to reduce the risk of colorectal cancer. Aim for the minimum U.S. dietary reference intake of 25 grams of fiber a day.
- Spice up your food. Curcumin is a cancer-fighting nutrient derived from the spice turmeric, which is often used in curry. Research has shown that curcumin may help prevent colorectal cancer.
Early Detection Makes a Difference
The New York Times may have called it "the most unloved cancer screening test," but colonoscopy can save lives, as new research demonstrates: The study, published in the New England Journal of Medicine (NEJM), found that people who had adenomatous polyps identified and removed during a colonoscopy were 53 percent less likely to die from colorectal cancer than those who didn't have the test. That's strong evidence of what many doctors have long suspected: Colonoscopy is vitally important.
Today, colonoscopies are more mainstream -- and media-friendly -- than ever. News anchor Katie Couric underwent a colonoscopy screening on live TV; Ozzy and Sharon Osbourne (a colorectal cancer survivor) teamed up with CBS Cares Colonoscopy Sweepstakes to promote a three-day trip to N.Y. and a free colonoscopy; and Dr. Mehmet Oz brought attention to colonoscopy when he himself had a cancer scare. Such public discussion of a very private issue is raising awareness among millions of Americans in the hope of saving lives.
I want to add to that discussion here by emphasizing how important, effective, safe and valuable colonoscopy is as a screening tool. It's been estimated that more than 50,000 people die each year from colorectal cancer -- but no one should be dying from it, due to the easy access of a colonoscopy procedure, which is covered by most insurance companies. "Many people dislike having the procedure," write the researchers of the NEJM study. "However, a colonoscopy doesn't have to be completed each year." If no polyps are found, you need a colonoscopy just once every 10 years.
Screening for average risk individuals begins at age 50, though studies suggest that African-Americans should begin at age 45. The advice varies for those in higher risk groups:
- People with a sibling, parent or child with colorectal cancer or an adenomatous polyp diagnosed at younger than age 60 or with two first-degree relatives diagnosed with colorectal cancer at any age should have a colonoscopy starting at age 40, or 10 years younger than the earliest diagnosis in their family, whichever comes first.
- If you have a history of adenomas with advanced tissue histology or if your doctor has diagnosed you with more than three polyps during an exam, you should have your first follow-up colonoscopy in three years. Patients with one or two small adenomas should have their follow-up colonoscopy in five years.
- If you have a strong family history of colorectal cancer -- especially if the cancers occurred before age 40 -- you should consider genetic testing for hereditary non-polyposis colorectal cancer and undergo a colonoscopy starting at age 20 or 25, or 10 years earlier than the youngest age of colorectal cancer in the family, whichever comes first.
- Individuals with inflammatory bowel disease should undergo a colonoscopy beginning eight to 10 years from the time of diagnosis or at age 50, whichever occurs first.
Colorectal Cancer: Catch It Before It Catches You!
To your good gut heath,
For more by Gerard E. Mullin, M.D., click here.
For more on personal health, click here.
For more on cancer, click here.
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