Colorectal cancer seems to be less frequently discussed than prostate and breast cancers. However, it is one of the leading causes of cancer deaths. It may develop for many years, without giving any sign. How can you protect yourself?
Screening for early detection saves lives. But when is it a right time to start screening? This article explains how to prevent colorectal cancer and discusses available screening options.
What is colorectal cancer?
Cancer occurs when normal cells are damaged, but instead of dying, they divide and grow uncontrollably. Colorectal (colon) cancer originates from cells of the large intestine or the rectum.
Usually, this type of cancer begins as a small mass of benign changes formed in the colon called polyps. However, over time, they may transform into cancer.
In the U.S., colon cancer is one of the most prevalent causes of cancer deaths. Therefore, early diagnosis is crucial for successful treatment.
What are risk factors and colon cancer causes?
Several causes may contribute to development of colon cancer. Usually, the disease results from a combination of them. Almost all colon cancers start with noncancerous lesions called polyps that transform into malignancies after some time.
The most significant risk factors for this disease include:
- Age. People over 45 are more likely to get colon cancer.
- Genetics or family history. If you have a close relative with colon cancer, you may have a cancer-promoting mutation.
- Inflammatory bowel disease. Bowel diseases such as Crohn’s disease or ulcerative colitis increase your risk of developing colon cancer.
- Genetic diseases. Hereditary conditions such as FAP (familial polyposis) or Lynch syndrome (hereditary non-polyposis colorectal cancer) raise cancer risk.
- Diabetes. People with diabetes or insulin resistance are at higher risk of developing colon cancer.
- Obesity. In obese people, the likelihood of getting ill and dying of colon cancer is higher.
- Smoking and drinking alcohol. Cigarettes and alcohol can increase your risk of getting cancer.
- Western diet, high in saturated fats, low in dietary fibre, and rich in red meat or processed meats has been linked to an increased risk of colorectal cancer. Data on the meat contribution is inconsistent. In the relevant studies, it was hard to distinguish from the influence of other factors like the lack of physical activity.
- Low physical activity. A sedentary lifestyle increases your risk for developing this disease.
- Ethnicity. African Americans and Eastern Europeans are more prone to colon cancer.
- Radiotherapy. A history of radiotherapy in the abdomen area increases your chance of colon cancer.
Colon cancer – symptoms
Precancerous growths, called colorectal polyps, and even cancer itself, may not give any signs, especially at the beginning. So, this is why you should screen for colon cancer regularly.
Colon cancer symptoms include:
- abdominal pain, cramps, gases, or tenderness,
- blood in the stool,
- weight loss without cause,
- diarrhoea, constipation, or any changes in stool consistency and toilet routine,
- feeling as if the bowel is still full after emptying,
- narrow, „pencil-like” stools,
- fatigue.
If you observe any of the signs listed above, see your doctor immediately.
How to reduce the risk of colon cancer? Prevention
You cannot change some facts, like being a carrier of cancer-promoting genetic mutations. But healthy lifestyle choices may reduce your risk.
Follow the following tips:
- Be physically active.
- Take a closer look at your diet. Eat more fresh fruit and vegetables and restrict your intake of red, processed meats.
- Quit smoking.
- Keep a healthy body weight.
Screening for colon cancer means having tests when the symptoms have not manifested yet.
Adults over 45 years of age should undergo screening for colon cancer. A colonoscopy or sigmoidoscopy, an examination used to diagnose colon cancer, can detect it at its early stages when the chances to treat it successfully are high.
Screening tests use special instruments to view your colon. They may also help find cancer or polyps before they transform into cancer. The doctor may surgically remove identified polyps to prevent development of colon cancer.
What is a colonoscopy?
A colonoscopy is the standard screening test for colon cancer. How is it done? The doctor introduces a thin, flexible, lightened tube to the colon. This way, they can checks the entire colon for polyps or cancer. Immediately on detecting any lesion of this kind, the doctor may remove polyps and some cancers.
Doctors would use colonoscopy as a confirmatory test if other tests found anything suspicious. People who are at average risk for the disease, should have a colonoscopy every ten years.
Patients below 45 years of age who are at higher risk of developing colon cancer, should discuss with their doctor when they should start screening and with what frequency.
The United States Preventive Services Task Force recommends that people between 45 to 75 years old should be screened for colorectal cancer.
During a physical exam, the doctor will press your abdomen to search for any a lumps in the belly. A rectal exam may reveal cancer in the rectum but not in the large intestine.
Other screening strategies include
- Stool tests. They detect blood in the stool (should be done once a year) or altered DNA (once every three years).
- Flexible sigmoidoscopy. The doctor introduces a short, thin, flexible, and lightened tube into the rectum to search for polyps or cancer in the rectum and the third part of the colon. Preferably, you should undergo it every five years.
- Computed tomography (CT) colonography (known as virtual colonoscopy). The exam uses X-rays and computer software to produce images of the entire colon that the doctor can analyse on the screen. You should undergo this scan every five years.
Which screening test is suitable for you? It depends on your health, preferences, family history, or resources. First, discuss with your doctor the pros and cons of all methods. Then, decide which is best for you and how often you should undergo tests.
Colon cancer treatment
If, unfortunately, you have colon cancer, your doctor will do more tests. They include blood tests for tumour markers, and CT or MRI (Magnetic Resonance Imaging) scans of your abdomen, chest and pelvic area, to find cancer site and whether it has spread to other organs.
The treatment type depends on the malignancy and stage of development and how far cancer has spread. Usually, doctors use surgery, chemotherapy, radiotherapy, and immunotherapy, administered alone or combined.
The colon cancer prognosis is good for early stage tumours. Nine out of ten cases diagnosed early end with recovery. It means patients survive for at least five years after their diagnosis.
To wrap up
Colorectal cancer is one of the most common death causes. Many risk factors, such as a sedentary lifestyle, an unhealthy diet, and hereditary predispositions, may raise your risk for this disease. To some extent, you can influence it, by eating healthy foods and exercising more. Screening also can prevent cancer – colonoscopy detects colon polyps, lesions that turn into cancer if not removed. There are plenty of ways to treat colon cancer, and treatment at an early stage is most efficient.
Talk to your doctor about scheduling your screening tests if you are 45 years old, or before you reach that age when you are at higher risk for that disease.