Colon cancer
Colon cancer is a common cancer. About five percent of all Flemish people are confronted with it. In Belgium, about 8,500 people per year are diagnosed with colon cancer, of which about 5,600 in Flanders. About 1,750 people die from it every year in Flanders.
The cancer usually occurs above the age of fifty. It affects slightly more men than women. In men it is the third most common tumor (after prostate and lung cancer), in women the second (after breast cancer).
Colon cancer almost always arises from a polyp . This is a bulge due to a thickening of the mucous membrane in the intestinal wall. There are different types of polyps. Most are benign and do not cause any complaints. However, some tend to undergo a number of changes during their growth, which can cause them to develop into a malignant tumor or colon cancer. The development of a polyp into cancer is very slow and takes an average of seven to ten years .
What are the causes?
There is no clear cause for the development of colon cancer. Various factors may contribute to this, often several at the same time, but not all of them are yet known.
Colon cancer is noticeably more common in some families than in others. Colon cancer in a first-degree relative (parent, brother, sister or child) increases the risk of developing colon cancer themselves. About twenty percent of colon cancers occur in people with a family history. The younger the affected family member, the greater your deductible. If you ever had colon cancer, your risk of developing it again is also increased.
Only a small proportion, five percent of people with colorectal cancer, also have a genetic abnormality . These forms of colon cancer are hereditary. Almost everyone with this abnormality will develop colon cancer later in life.
Other risk factors
- Increasing age: ninety percent of people with colon cancer are over fifty years old;
- Chronic intestinal infections such as Crohn's disease and ulcerative colitis;
- An unhealthy lifestyle:
- unbalanced diet with too few vegetables, fruit and fiber, too many fats and red or processed meat;
- smoking;
- excessive use of alcohol;
- overweight;
- insufficient exercise.
What are the symptoms?
Colon cancer does not always cause symptoms and the symptoms are usually vague .
Nevertheless, the following complaints may indicate colon cancer if they have been present for a longer period of time :
- blood or mucus in stools;
- abdominal pain or cramps;
- a change in stool (irregular bowel movements, constipation, diarrhea);
- a false urge to defecate.
Sudden and unexplained weight loss, prolonged loss of appetite or persistent fatigue can also be an alarm signal .
These complaints do not necessarily indicate colon cancer. Many other conditions can be the cause.
When to go to the doctor?
See your doctor if you have any of the symptoms. Your doctor will, based on a thorough questioning and in consultation with you, determine whether further testing is appropriate.
You can also contact your doctor:
- with questions about whether or not to participate in the population screening;
- to discuss the advantages and disadvantages of the follow-up test if the population screening gave an abnormal test result;
- for a possible referral to a gastrointestinal specialist.
How does the treatment proceed?
The treatment of colon cancer varies from person to person. A team of different specialists discusses the best approach.
The most common treatments are surgery, chemotherapy and radiation. Which combination gives the best chances of recovery or healing depends on:
- the location, size and nature of the tumor,
- any metastases,
- the age and general health of the patient.
During a visual examination (colonoscopy) the inside of the intestine is inspected. Polyps and pieces of tissue from suspicious lesions (biopsies) are removed and examined in the laboratory for malignant cells.
When colon cancer is diagnosed, many other tests are performed, such as an X-ray of the lungs, an ultrasound of the liver, a CT scan, and sometimes also an MRI scan or a PET scan. This determines the stage of the tumor and the possible presence of metastases.
A colon tumor is usually removed via surgery . This involves cutting away the tumor and a piece of surrounding tissue. The lymph nodes near the tumor are also removed and then examined for malignant cells.
After an operation, a stoma is sometimes created, whereby the exit of the intestine is attached to the abdominal wall. In the meantime, the intestine can recover. After a few months, the intestine can be sewn back together and the stoma removed. In some cases it is necessary to keep the stoma permanently.
Depending on the stage at the time of diagnosis, any gland involvement and the presence of metastases outside the intestine, a decision may be made to administer chemotherapy, with or without combination with monoclonal antibodies or cytokines.
In colon cancer, radiation is almost exclusively used for tumors in the rectum . The aim is usually to reduce the size of the tumor so that surgery has a greater chance of success.
What can you do yourself?
Healthy lifestyle
You can't prevent the disease, but a healthy lifestyle can reduce the risk .
- Ensure a balanced diet with sufficient fiber. Be moderate in animal fats and avoid red or processed meat.
- Exercise enough.
- Fight obesity.
- Quit smoking .
- Moderate your alcohol consumption.
Early detection
Colon cancer almost always arises from a polyp. The development of a polyp into cancer is very slow and takes an average of seven to ten years. By detecting and removing degenerated polyps at an early stage, fewer suspicious polyps can develop into colon cancer. The surgery and treatments will also be less invasive and the mortality rate will decrease. If the cancer is detected early, there is more than a ninety percent chance of being cured.
It is important to detect and treat the cancer before symptoms appear . These often only occur when the tumor is already quite large. The more advanced he is, the worse the expectations.
Why and for whom does a population survey take place?
A population survey is taking place in Flanders to detect colon cancer. Men and women aged 51 to 74 are invited to participate every two years .
If you belong to the target group, you will receive an invitation at home. It also includes a kit to take a stool sample . You can send this sample to the laboratory together with a response form. There it will be examined whether your stool contains blood , which may indicate the presence of polyps or colon cancer. This examination is necessary because the traces of blood cannot be seen with the naked eye.
Do you have a first-degree relative (parent, brother, sister or child) with colon cancer or do you have an inflammatory bowel disease such as Crohn's disease or ulcerative colitis? Please contact your doctor first. Custom studies may be better for you.
The result of the test will be communicated to you and your doctor within fourteen days.
- If blood is present in the sample, this does not mean that you have cancer. After all, the traces of blood can also have other causes. A follow-up examination is recommended to determine whether the blood comes from a polyp or an intestinal tumor. A gastrointestinal specialist will check the inside of the colon with a visual examination (colonoscopy). This is done under anesthesia, during which a flexible tube with a camera is inserted into the intestine through the anus.
- If the test shows a normal result , this does not mean that no polyps are present. Some polyps are small and do not cause blood loss, but will grow slowly and cause blood loss later. That is why it is important to repeat the test after two years . For this purpose, you will receive a new invitation and collection set each time, up to and including the age of 74.
- Thanks to the examination, polyps or colon cancer can be detected early . As a result, the treatment is usually less difficult and the chance of recovery is greater.
- Participating in the survey is free .
- Taking and sending a stool sample is very simple .
- Both you and your doctor will receive the result fairly quickly .
- You can count on qualitative research and follow-up of the results.
- Continuous evaluation is possible through the population survey: number of participants, number of positive tests, number of people with appropriate follow-up after an abnormal test, number of cancers after an abnormal test. This provides important information for the organization and evaluation of the research. This means that quality is strictly monitored.
Participating in the population survey therefore has more advantages than the self-tests that you can purchase in the pharmacy.
- The test may be false positive . This means that traces of blood are found without evidence of polyps or colon cancer. This can cause you to be unnecessarily worried or anxious and to undergo a sometimes unnecessary visual examination.
- The test can be false negative . There may be a tumor that does not bleed in the week before the test, meaning that no traces of blood are present. This creates a 'false' sense of security.
- There are risks associated with a visual examination of the intestine: there is a 0.2 percent chance of bleeding and 0.05 percent of perforation of the intestinal wall.
- Because it is difficult to predict which polyps would develop further into colon cancer, polyps that would never develop into cancer are sometimes removed . In this way you are sometimes worried or treated unnecessarily.
Elise Rummens
Elise is onze huisdokter. Haar stokpaardje op het vlak van gezondheid is beweging. Daarom zie je haar op dinsdagavond springen, vliegen, duiken, vallen en weer opstaan. Dan heeft ze haar wekelijkse parkourtraining.
Preventie-arts CM