Colon cancer is one of the most common cancers. In Germany alone, over 50,000 people are diagnosed with colon cancer every year, and over 20,000 people die from the disease. This is often due to the fact that the cancer is discovered far too late – despite preventative measures.

Heidrun Thaiss explained in an interview with FOCUS online what this could be and how you can recognize the symptoms early. She is a doctor and one of the managing directors of the Felix Burda Foundation*, which is committed to the prevention of colon cancer.

FOCUS online: Ms. Thaiss, one of the reasons why colon cancer is often detected too late is the non-specific symptoms. So symptoms that go under the radar and don’t immediately make you think of colon cancer. Which are these?

• weight changes due to loss of appetite,
• sleep disorders,
• Fatigue,
• exhaustion
• or maybe even a slight fever.

And of course you don’t primarily think of colon cancer. If such symptoms persist, i.e. last longer than four weeks, you should contact your family doctor and have this clarified. You can then usually carry out laboratory tests, which then provide further information in the right direction.

And what’s more: we also have different types of people. Some say: ‘Oh, it’s all harmless, there’s definitely nothing there. I have that more often.’ And others, whom we also call hypochondriacs or phobics, take every little sign seriously. And it’s important to keep a balance, so to actually listen to the voice of your own body and say: ‘I know myself, there’s something wrong, I should get it checked out.’

FOCUS online: There is also an early detection program in Germany.

Thaiss: Men and women over the age of fifty can have an immunological stool test, i.e. a test for traces of invisible blood in the stool. This happens every two years. Men and women over the age of fifty are entitled to colonoscopy twice at an interval of ten years. Both tests are about equally good and equally valid when it comes to detecting colon cancer.

However, it must be said that colonoscopy, i.e. colonoscopy, of course offers completely different options. When doctors look in there, they can also see the precursors of cancer, the polyps, in the intestine. And these polyps do not have to be cancerous and have cancer cells in order to be recognized. When I see this, I can remove it straight away and thus prevent cancer. So that’s the advantage of colonoscopy.

Instead, in immunological stool tests, blood can often only be detected when there is already cancer or when a polyp already has cancer cells. Because they don’t normally bleed at this stage. However, they can sometimes give off very small traces of blood, which the test then detects.

FOCUS online: Nevertheless, the participation rate is relatively low, at least in Germany. Between 2010 and 2022, only around twenty-three percent of men and a little more than half of women between the ages of fifty and fifty-four took the stool test at least once. Only around one percent do this regularly, one shows study. The numbers do increase during colonoscopy, but are still very low. Why do you think that is?

Thaiss: It could be ignorance, meaning that you have never heard of it. Or that you think, ‘Oh, that doesn’t concern me’. There are many prejudices and myths surrounding this disease and the examinations. For example, that cancer is only a disease of old age.

When it comes to a colonoscopy, for example, it is also said that doing it the day before is annoying, unpleasant and takes time. Somehow it doesn’t fit into people’s everyday lives. That may be true – but you also have to say it’s worth it. The cleaner the intestine is, the more the doctor can see and the sooner he can see and remove the intestinal polyps in the corresponding folds. Nowadays there are drinking solutions for laxatives that don’t taste so bad anymore, so you don’t have to choke them down with your nose held.

One of the myths is that the examination is very painful. In the past it has happened that the examination may have caused some pain afterwards, a slight stomach ache. But that is no longer the case. We have new methods.

Another obstacle we observe is the so-called prevention paradox. Such a screening is a so-called secondary preventive measure. This means that we have to decide to do this when we don’t have any symptoms yet. We feel healthy and have no pain or other symptoms. Nevertheless, we should interrupt our everyday life and then go for an examination like this, which is fraught with many myths. So in this respect, the insight into doing something before you really notice warning signs is always a relatively big hurdle.

FOCUS online: Colonoscopy is not completely risk-free. Complications can occur, although they are very rare. For example, cardiovascular problems or a perforation of the intestinal wall. Intestinal contents can get into the abdominal cavity, which requires immediate surgery. Critics say that many of those examined do not have an increased risk of colon cancer and therefore only a small group actually benefits directly from the examination – but everyone bears the risks. Would it make more sense to focus screening more closely on individual risk?

Thaiss: It’s an intervention. But it is an intervention that definitely pays off. Precisely because we know that the sooner we prevent it – either when there are no cancerous growths or only minimal changes are present – the chances of recovery are over 90 percent. Then every life saved that this makes possible is actually worth it. The benefits and risks clearly outweigh the benefits.

Nevertheless, risk-adapted prevention makes sense. We see worldwide that the incidence of cancer also increases at younger agessometimes from the age of twenty. At the same time, of course, we cannot screen all people between the ages of twenty and fifty. That would be disproportionate. But there are certainly ways to identify risks early. It is therefore important that family doctors take a thorough family history and ask:

1. Is there a family history of cancer, especially colon cancer, especially at younger ages?
2. Have there been deaths of parents, grandparents or siblings?

For example, you can have a family history of an increased risk of cancer such as Lynch syndrome (genetic disease that is associated with an increased risk of colon cancer; Note d. Red.) identify early.

FOCUS online: What role does lifestyle play?

Thaiss: When people think of heavy smokers, the first thing that comes to mind is lung cancer. But you also have an increased risk of colon cancer, as well as breast cancer in women. Tobacco and excessive alcohol consumption are recreational poisons and cell toxins that have an effect throughout the body.

There are also diseases such as Crohn’s disease or ulcerative colitis, chronic inflammatory bowel diseases. And we know: Inflammation is a risk factor for cancer because cell turnover is increased. This also increases the likelihood that individual cells will degenerate and the body’s own repair mechanisms will at some point be overwhelmed. It is therefore important and right to generally think about risk-adapted early detection for tumor diseases.

FOCUS online: Smoking, unhealthy diet or lack of exercise are repeatedly linked to the development of many diseases, not just colon cancer. They are preventable, but many diseases still arise because of them.

Thaiss: For a long time, prevention was just a ‘nice to have’. Only when all other pressing questions had been dealt with did we turn to prevention again. Instead, we only react when the illnesses are already there. We have very good outpatient and inpatient care. But we also know that all of this costs money. What we have not yet discovered is the potential that prevention offers to forestall this overburdened healthcare system. We know that prevention pays off. Calculations show: It pays off twice.

We have several options:

1. We have them Primary prevention. This is general health promotion, preventing illnesses before they arise.
2. We have them Secondary prevention with the early detection system, which is very good for us.
3. And we have them Tertiary prevention. The aim is to prevent illnesses from getting worse.

In addition, there is behavioral prevention of individuals. So the appeal to their lifestyle, to reason. We know that this only has a very limited effect. The environment must therefore support people in their behavior. For example, if I recommend: ‘Get moving, get out’, and I have a four-lane road in front of my door, then that’s difficult. But if we turn a lot of adjustment screws in this complex system, then we can make a lot of difference.

*Like FOCUS online, the Felix Burda Foundation belongs to Hubert Burda Media.