With Colon Cancer Awareness Day in March, we’ve put together this article on the main symptoms of the disease, risk factors, the importance of screening, and, of course, preventive measures!
What is colon cancer?
The colon, also known as the large intestine, is the final part of the digestive tract. Its role is to reabsorb water and minerals from digested food and store waste before elimination.
Colon cancer—sometimes referred to as colorectal cancer when it also includes the rectum—typically develops when certain cells grow abnormally. This process often begins with the formation of adenomatous polyps, small growths on the inner wall of the colon. Over time, some of these polyps can turn into malignant tumors if not detected and removed.
Colon cancer statistics in Switzerland
Colon cancer is one of the most common cancers worldwide. In Switzerland, the Swiss Cancer League estimates that around 4,500 new cases are diagnosed each year, making it the third most common cancer in the country.
In terms of mortality, colorectal cancer is responsible for approximately 1,600 deaths per year in Switzerland, with 900 deaths among men and 700 among women.
According to the Swiss Cancer League, the risk of developing this disease increases with age, with most cases diagnosed in people over 50. Thanks to screening methods, early detection can significantly improve treatment success and survival rates.
The five-year survival rate after a colorectal cancer diagnosis is 67% for men and 66% for women. The earlier the cancer is detected, the better the chances of recovery. That’s why it’s important to pay attention to the symptoms outlined below.
Colon cancer symptoms: What to watch for
Different warning signs can appear, though some may be subtle or even nonexistent in the early stages.
Common signs of colon cancer
1. Blood in the Stool
- This can be bright red blood or darker, tarry stools (melena).
Good to know: Blood in the stool is not always visible to the naked eye (this is called occult blood).
2. Changes in bowel habits
- Persistent diarrhea or constipation episodes.
- Changes in stool frequency or consistency lasting for several weeks.
3. Abdominal pain or cramps
- Diffuse or localized pain, sometimes accompanied by bloating.
4. General fatigue and unexplained weight loss
- Anemia (low red blood cell count) can develop if you are losing blood unnoticed, leading to chronic fatigue.
- Unintentional weight loss may also indicate an underlying health issue, particularly in the digestive system.
Blood in stool: Is it hemorrhoids or cancer?
Not all cases of blood in the stool indicate colon cancer. Hemorrhoids are a common cause of rectal bleeding—they are swollen or inflamed veins in the anal region. Bleeding from hemorrhoids is usually bright red, visible on toilet paper or on the stool’s surface, and may be accompanied by itching or a burning sensation.
However, if you notice darker blood mixed with stool or experience unusual and persistent abdominal pain, a more thorough medical evaluation is recommended. A healthcare professional should be consulted to determine the exact cause of the bleeding.
Colon cancer risk factors
Several factors can increase the risk of developing colon cancer.
Age and family history
- The risk increases with age, especially after 50.
- Having a close relative (parent or sibling) with colon cancer or adenomatous polyps (abnormal growths in the colon or rectum) raises the likelihood of developing the disease.
Adenomatous polyps (precancerous polyps)
- Certain polyps have a high potential to become malignant.
- They often go unnoticed without screening.
Chronic inflammatory bowel diseases
- Conditions such as Crohn’s disease or ulcerative colitis cause long-term inflammation of the intestinal lining.
- Prolonged inflammation can promote the development of abnormal cells in the colon.
Colon cancer prevention
Even if you have risk factors, there are many habits you can adopt to lower your risk of colon cancer.
Healthy diet
- Increase fiber intake: Eat more fruits, vegetables, legumes, and whole grains.
- Limit red meat and processed meats, as they may increase cancer risk.
- Avoid excessive sugar and saturated fats: Choose healthy fats like olive oil. If you need tips or recipes, check out our nutrition articles!
Lifestyle habits
- Avoid tobacco and alcohol: Smoking contains carcinogens, and excessive alcohol consumption can also contribute to cancer development.
- Exercise regularly: Studies show that engaging in physical activity (brisk walking, running, cycling, swimming) improves digestion and reduces systemic inflammation, promoting colon health.
Regular medical checkups
- See a general practitioner or a gastroenterologist if you have a family history or persistent symptoms.
- Get screened for colon cancer (FIT test or colonoscopy) at the recommended ages or as advised by your doctor.
Colon cancer screening
Screening is one of the most effective ways to combat colon cancer. It allows for early detection of the disease or precancerous lesions (such as polyps) before they become malignant.
In Switzerland, colon cancer screening is not always free, but basic health insurance often covers it for individuals aged 50–69. In some cantons, organized screening programs are available.
Screening methods
- Fecal immunochemical test (FIT)
- Easy to do: You collect a stool sample at home and mail it to a laboratory to check for invisible blood.
- A positive result doesn’t necessarily mean cancer but indicates the need for a colonoscopy for further examination.
- Good to know: If you’re between 50 and 69, this test is covered every two years.
- Colonoscopy
- This is the most comprehensive screening method and allows for preventive removal of suspicious growths. A gastroenterologist examines the inside of the colon directly.
- If polyps are found, they can be removed immediately and analyzed.
- Good to know: If you’re between 50 and 69, a colonoscopy is covered every ten years.
When in doubt, consult a specialist!
Noticing blood in your stool? Experiencing chronic abdominal pain or persistent fatigue? If so, a medical consultation is essential. By speaking with your doctor, you can determine if a screening test or further treatment is necessary.
Book an appointment online with the right specialist—whether it’s a general practitioner or a gastroenterologist—to assess your symptoms and consider screening (colonoscopy or FIT test).
Sources:
- Swiss cancer screening – Fakten zu DarmkrebsAmerican Cancer Society – Colon and Rectal Cancer Prevention
- Auer, R., Selby, K., Bulliard, J., Nichita, C., Dorta, G., Ducros, C., & Cornuz, J. (2015, November 25). Programme cantonal vaudois de dépistage du cancer colorectal :information et décision partagée. Revue Medicale Suisse.
- Darmzentrum Bern – Risiko und Vorsorge Dickdarmkrebs – Darmspiegelung
- Hôpital de La Tour – Colon cancer and colorectal cancer
- Krebsliga – Darmkrebs
- Krebsliga – Früherkennung von Darmkrebs
