Colon cancer is common and deadly. It’s the third most common cancer diagnosed in both men and women in the US, and 90% of colon cancers are diagnosed in people over the age of 50. Thankfully, the incidence of colon cancer has been on the decline for the past decade, dropping 2 to 3% per year. This is due to better awareness in screening and better lifestyle choices.
About 70% of all colon cancers are due to environmental and dietary factors, while the remaining 30% are due to inherited and familial causes.
Lifestyle factors associated with colon cancer:
- Eating an unhealthy diet (including processed, fatty foods, and red meat)
- Being over age 50
- Living a sedentary lifestyle
- Excessive alcohol intake (having two or more drinks a day)
- Having adenomatous polyps before age 60 years
- Being African-American
- Being in lower socioeconomic classes
- Not getting proper screening
Inherited and “familial” factors that influence colon cancer:
If you have a first-degree relative (a parent, child or sibling) who has colon cancer, your risk of colon cancer is almost double that of the general population. The most common types of familial colon cancer include Familial adenomatous polyposis (FAP) and Lynch Syndrome. These conditions make up 5% of the causes of colon cancer.
Other risk factors for colon cancer include those with inflammatory bowel disease such as Ulcerative colitis and Crohn’s disease. Low Vitamin D has also been associated with an increased risk.
Protective factors that may decrease your risk of colon cancer include regular physical activity, a diet rich in fruits and vegetables, and a high-fiber diet. Omega 3 fish oil has also been associated with a decrease risk of colon cancer. Dietary folic acid, Vitamin B6, calcium and garlic may also provide some protection. Aspirin and NSAID’s may also protect against polyps of the colon as well as colon cancer.
Colon cancer screening saves lives.
Consistent and regular screening will reduce your risk of developing colon cancer up to 90%. If colon cancer is detected early, the chance of a successful treatment and long-term survival is substantial.
In the early stages of colon cancer, you may not experience any symptoms. However if you experience any of these symptoms you should alert your health care provider:
- Rectal bleeding or blood in your stool
- A noticeable, inexplicable change in bowel habits, such as constipation or diarrhea or a change in consistency and shape.
- Persistent bloating, cramping, gas or pain
- Fatigue or weakness
- Unexplained weight loss
The Dreaded Prep
In order for the gastroenterologist to see your entire colon, it must be completely clean, and no stool can be present. For best results, you should follow a 24-hour liquid diet. If the prep is not done correctly, it can be challenging to get an adequate colonoscopy (and to reassure you that there are no polyps or tumors present).
The colonoscopy is typically done in an outpatient setting with mild sedation. A thin tube is passed through your colon as the doctor looks onto a television screen evaluating its entirety. The procedure takes less than an hour and complications are rare.
Screening guidelines for colonoscopy:
- Beginning at age 50, all adults should undergo a colonoscopy, although African-Americans should consider a colonoscopy at 45.
- If you have normal results, you should get a colonoscopy every 10 years.
- A virtual colonoscopy (or "computed tomographic colonoscopy") begins at age 50. This new and alternative way of looking for polyps and other abnormalities of the colon is done by a radiologist and does not require any sedation—but you still need to do the prep! Every five years is the typical screening cycle if you have normal results.
- Stool tests (fecal occult blood tests) should begin annually for people ages 50 and older. This non-invasive, inexpensive and simple test allows health care providers to check for microscopic blood in stool during your yearly checkup.
- People over 75 with consistently negative colonoscopies do not need additional testing.
- Colon cancer screening should begin as early as age 40 for those with a family history of polyps in relatives under age 60.
Other less comprehensive options for screening tests include:
- Double-contrast barium enema every 5 years using x-rays to view parts of the colon and rectum.
- Flexible sigmoidoscopy every 5 to 10 years only visualizes the lower 1/3 of the colon. This should be combined with combined with FOBT.
Consult with your health care provider for further information relating to your own medical history and colon cancer risks.
Photo Credit: Shutterstock.com