Bowel cancer is a malignant growth that develops from initially benign mucosal growths. These are intestinal polyps (protrusions of the intestinal mucosa) or adenomas (benign tumors made of mucous membrane or glandular tissue). The following video shows how these develop:
If the malignant growths are in the colon, they are called colon carcinoma; if they are in the rectum, they are called rectal carcinoma.
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Colon cancer develops over a long period of time and is often not noticed at first. Symptoms only appear when the tumor has reached a certain size. Even then, the symptoms are rather unspecific and can also be caused by a variety of other diseases. Because the cancer develops so slowly, the earlier bowel cancer is detected, the better the chances of recovery.
Symptoms that can occur as the disease progresses are
Bowel cancer screening is one of the early detection programs offered by statutory health insurance companies. From the age of 50, a so-called haemoccult test (also known as a guaiac test) is paid for annually by the health insurance companies. This provides a rough indication of whether further examinations are necessary. From the age of 55, a colonoscopy is then carried out every ten years. If someone is unable or unwilling to undergo a colonoscopy, a haemoccult test can also be carried out every two years. The doctor may also carry out a digital rectal examination.
In some cases, doctors recommend bowel cancer screening before the age of 50. This applies, for example, to people at risk. These include, for example, people with first-degree relatives who have been diagnosed with bowel cancer. They should go for screening ten years before their relative is diagnosed for the first time, but at the latest by the age of 40 or 45. Before this, it is a good idea to discuss with your health insurance provider whether the costs can be covered.
There are also hereditary diseases, such as Peutz-Jeghers syndrome (increased occurrence of polyps in the stomach and intestines), which increase the risk of bowel cancer. People with these diseases receive a personalized bowel cancer screening plan from their doctor. This plan is drawn up by the doctor in accordance with the guidelines for the diagnosis of genetic predisposition to cancer issued by the German Medical Association.
Haemoccult test
In this test, the patient's stool is examined for occult, i.e. invisible, blood. To do this, the patient applies stool to a paper strip with a spatula on three different days. The doctor can then analyze the samples himself or send them to a laboratory. A positive test result indicates traces of blood in the stool. The test can detect around half of all colon cancers.
However, a positive test does not necessarily mean that the person concerned has colon cancer. The occult traces of blood can also have other causes. For example, hemorrhoids or bleeding gums can also be the reason for a positive test. Raw meat, certain vegetables and various medications such as acetylsalicylic acid (ASA) or iron tablets can also be a trigger for a falsified test. For this reason, a positive test must be followed by a colonoscopy. This can clarify the exact reason for the occult blood in the stool.
Digital rectal examination
The digital rectal examination, also known as DRU, is used to clarify changes in the rectum. To do this, the doctor palpates the rectum with a finger. For the examination, the patient can either lie on their left side on an examination table or be examined standing up with their upper body bent forward. Wearing gloves and lubricant, the doctor then gently inserts the finger rectally. He then feels the wall of the rectum for changes. The examination only takes about a minute in total. However, it can be life-saving in the case of rectal cancer, which is why this examination should not be omitted.
Colonoscopy
Colonoscopy is the most important and safest method for detecting bowel cancer. An endoscope is inserted into the bowel via the anus. The patient is only lightly sedated for this. The endoscope is a flexible tube equipped with a light source and a camera at the end. Through the camera, the doctor can see images of the inside of the bowel on a monitor and examine it for abnormalities. The main focus is on polyps, as these can develop into bowel cancer over the years. If polyps are discovered, they can be removed directly during the colonoscopy. Tissue samples can also be taken from conspicuous areas of mucous membrane during the colonoscopy.
Overall, a colonoscopy carries only a few risks. The endoscope can cause injury to the intestinal wall. However, this complication is rare and the benefits of a colonoscopy outweigh the risks, as it can detect bowel cancer at an early stage.
It is particularly important to take advantage of screening examinations. However, a healthy lifestyle can also be beneficial. For example, you should not smoke and only drink alcohol in moderation. A diet low in meat and high in fiber with plenty of fruit and vegetables is also helpful. This also applies to sufficient physical activity. These measures result in the stool passing through the digestive tract more quickly. Toxins that may be present in the food have less time to damage the intestinal mucosa. Obesity and diabetes can also have an influence on the development of bowel cancer due to increased insulin levels. For this reason, people in these risk groups should definitely take advantage of preventive offers.
