Colon Cancer – Symptoms and Causes
Overview
Colon cancer develops in the colon, the longest section of the large intestine. This disease typically affects older adults but can occur at any age.
Most colon cancers begin as small, noncancerous growths called polyps that form on the inner lining of the colon. Over time, some of these polyps can become cancerous.
Polyps rarely cause symptoms, so regular screening is crucial for early detection. Doctors recommend routine screening tests to find and remove polyps before they develop into cancer.
Common screening methods include:
- Colonoscopy
- Stool-based tests
- CT colonography
- Flexible sigmoidoscopy
When colon cancer is diagnosed, several treatment options are available:
| Treatment Type | Description |
|---|---|
| Surgery | Removes cancerous tissue |
| Radiation therapy | Uses high-energy beams to kill cancer cells |
| Chemotherapy | Uses drugs to destroy cancer cells |
| Targeted therapy | Focuses on specific abnormalities |
| Immunotherapy | Helps the immune system fight cancer |
Colon cancer is often classified with rectal cancer as “colorectal cancer” since they are connected in the digestive system. The digestive system processes food for the body’s use, with the large intestine functioning as its final segment.
Signs to Watch For
Many people with colon cancer have no symptoms in the early stages. As the disease progresses, you might notice:
- Changes in Bowel Habits (persistent diarrhea or constipation)
- Blood in Stool or Rectal Bleeding
- Stomach Discomfort (cramps, gas, or pain)
- Feeling of Incomplete Bowel Movements
- Unusual Fatigue or Weakness
- Unexplained Weight Loss
When to Contact a Healthcare Provider
If you have any symptoms that last more than a few days or keep coming back, schedule an appointment with your doctor. Don’t wait for symptoms to get worse before seeking medical help.
Early detection gives you the best chance for successful treatment.
Causes
The exact cause of most colon cancers remains unknown to medical professionals. However, research shows that colon cancer develops when DNA changes occur in the cells lining the colon.
These DNA changes disrupt normal cell functions in two important ways:
- They trigger abnormally rapid cell multiplication
- They prevent cells from dying when they should naturally
This combination leads to an excess of cells that may form tumors. These abnormal cells can:
- Invade nearby healthy tissue
- Destroy normal body structures
- Eventually, break away from the original site
- Travel to distant body parts (metastasis)
When cancer cells spread from their original site, it’s called metastatic cancer, and it is harder to treat than localized cancer.
Risk Factors
Several factors may raise your chances of developing colon cancer:
Age Considerations
- Most cases occur in people over 50
- Rising cases among those under 50, for unknown reasons
Racial Factors
Black Americans face a higher colon cancer risk compared to other racial groups.
Medical History
Having previously had colon cancer or polyps increases your risk of developing the disease again. Inflammatory bowel conditions like ulcerative colitis and Crohn’s disease also raise your risk due to ongoing intestinal inflammation.
Genetic Factors
Some people inherit genetic changes that increase their colon cancer risk. The most common inherited conditions include:
- Familial adenomatous polyposis
- Lynch syndrome
Family History
Having blood relatives who have been diagnosed with colon cancer increases your risk of developing the disease. This risk grows with multiple affected family members.
Lifestyle Factors
| Factor | Risk Impact |
|---|---|
| Diet | High-fat, low-fiber diets increase risk |
| Physical Activity | Regular exercise lowers risk |
| Smoking | Increases colon cancer risk |
| Alcohol | Excessive drinking raises risk |
Health Conditions
People with diabetes, insulin resistance, or obesity face a higher colon cancer risk. Obesity also increases the chance of dying from the disease.
Previous Cancer Treatment
Radiation therapy directed at the abdomen for treating other cancers can increase colon cancer risk later in life.
These risk factors don’t mean you’ll definitely develop colon cancer. Many people with multiple risk factors never get the disease, while others with no known risk factors do.
Ways to Prevent Colon Cancer
Health experts suggest people with average risk begin colon cancer screening at age 45. Those with higher risk factors, such as a family history of colon cancer, should start screening earlier.
Healthy Habits That Lower Colon Cancer Risk
You can reduce your chance of developing colon cancer by making simple lifestyle changes:
Eat More Plant Foods: Include various fruits, vegetables, and whole grains in your meals. These foods contain fiber, vitamins, minerals, and antioxidants that may help protect against cancer.
Limit Alcohol: If you drink, keep it moderate—no more than one drink a day for women and two for men.
Quit Smoking: Consult your healthcare provider about effective ways to stop smoking.
Stay Active: Try to exercise for at least 30 minutes on most days. If you’re not used to exercising, start slowly and build up gradually. Check with your doctor before beginning a new exercise program.
Keep a Healthy Weight: Maintain your weight through balanced eating and regular physical activity.
Special Prevention for High-Risk Individuals
People with elevated colon cancer risk may have additional prevention options. Some research suggests regular use of aspirin or similar medications might reduce the risk of colon polyps and cancer.
However, researchers are still studying what dose and duration would work best. Taking daily aspirin carries risks, including potential stomach bleeding and ulcers. For this reason, medication-based prevention is usually only considered for high-risk patients.
