March is colon cancer awareness month.  We have made tremendous strides in the fight against cancer especially colon cancer.

Between 1991 and 2011, U.S. cancer death rate decreased by 22 percent (1.5 million lives saved), and colon cancer death rate decreased by almost 50 percent. This decrease coincides with widespread adoption of colorectal cancer screening particularly colonoscopy.

Despite this progress, colon cancer is still the 2nd leading cause of cancer death in the United States and disparity still exists in colorectal cancer statistics.  The incidence of colorectal cancer is 46.7 cases for every 100,000 black Americans, compared with 38.9 cases for every 100,000 white Americans.

Death from colorectal cancer is 21.1 cases for every 100,000 black Americans, compared with 14.6 cases for every 100,000 white Americans. Colorectal cancer screening rates are 56% in Blacks compared to 62% in Whites; 58% in women compared to 60% in men.

While overall colon cancer rates fell by 1% every year between 1975 and 2010, rates for younger Americans between 20 to 34 years rose by 2% annually and rates for those between 35 and 49 rose by half a percent.

Colon cancer is preventable. Here are three ways to prevent colorectal cancer.

1. Know your family history

When and how often to screen for colorectal cancer depends on your family history.

• Average risk individuals without family history of colon cancer should start at age 50.
• African-Americans should start at age 45 according to the American College of Gastroenterology.
• Individuals with one first degree relative with history of colorectal cancer or adenomatous polyps before the age of 60 or two or more first-degree relatives at any age should start screening at age 40 or 10 years earlier than the age of the affected relative.
• Individuals with a first-degree relative with a history of colorectal cancer or polyp at age 60 or older or two second-degree relatives with colorectal cancer should start screening at age 40.
• Individuals with familial adenomatous polyposis should start screening at age 10 to 12.
• Individuals with Lynch syndrome should start screening at age 20-25 or 10years younger than the youngest affected immediate relative.

2. Get screened

There are several ways to get screened for colorectal cancer including stool test, virtual CT scan of the colon and colonoscopy. The most effective is colonoscopy. Colonoscopy is unique because it can not only detect early colon cancer, it can prevent colon cancer. Colon cancer is prevented when pre-cancerous polyps are removed during colonoscopy.

Two important factors influence the yield of colonoscopy bowel preparation and the skill of the endoscopist (provider).

Poor bowel preparation prevents complete visualization of the colon wall and limits detection and removal of colon polyps. Poor bowel preparation has been shown to lower the detection of colon polyps by over 40 percent in one study.

The skill of the endoscopist is critical to the outcome of colonoscopy. Several metrics are available to assess the skill of the endoscopist. One of these metrics is the adenoma detection rate (ADR). It measures an endoscopist ability to detect and remove pre-cancerous polyps during screening colonoscopy. A good endoscopist should detect and remove pre-cancerous polyps in at least 20% of average risk patients undergoing screening colonoscopy.  Lower percentages have been associated with the risk of developing colon cancer in between screening colonoscopies.

• Get screened. Any test is better than none though colonoscopy is the best screening test.
• For your colonoscopy, make sure you have an adequate bowel preparation.
• Choose a highly skilled provider to perform your colonoscopy.

3. Change your lifestyle

Studies have shown an association between colorectal cancer and our lifestyles.

• Tobacco use is associated with colorectal cancer and other cancers.
• Drink alcohol in moderation. Excessive alcohol use increases of the risk of many cancers including colon cancer.
• Red meat is associated with increased risk of colorectal cancer. Research suggests that there is a 20 percent higher risk of colorectal cancer per 100 gram per day increase in red meat and 50 gram per day increase in processed meat.
• Fiber appears to lower colorectal cancer risk. Research suggests that there is a 10 percent reduction in colorectal cancer risk for every 10gram per day in dietary fiber intake.
• Obesity is associated with colorectal cancer. Studies have shown that colorectal cancer risk increases by 2 to 3 percent per unit increase in body mass index (BMI) and per inch increase in waist circumference.
• Physical activity reduces the risk of colorectal cancer regardless of body size and diet. The American Cancer Society recommends at least 150 minutes of moderate-intensity or 75 minutes of vigorous-intensity activity each week (or a combination of these), preferably spread throughout the week.

Colon cancer is preventable. Know your family history, get screened and have a healthy lifestyle.

Adewale Ajumobi is a gastroenterology fellow and editor, Bowel Preparation Guide.