Month: June 2020

Carrots are high in vitamin A and beta carotene, hence their name, and are important for the eyes and the immune system. Most of them do not know more about these vital substances – and this statement is sometimes even incorrect.

Vitamin A, provitamin A and beta carotene – what are they?

Because vitamin A is a complex of vitamins that includes retinol and retinyl esters . These forms are mainly found in animal foods.

There is also provitamin A as a precursor, which is found in plant-based foods. “There are also various representatives of provitamin A, the best known is beta carotene,” explains Andrea Henze, nutritionist at the University of Potsdam. The body has to convert provitamin A such as beta carotene into vitamin A so that it can be used. This processing takes place mainly in the intestines and liver.

Beta carotene – like all provitamins A – in turn belongs to the large group of carotenoids, of which there are more than 600 different ones. All of them have the property, as a natural coloring agent, of coloring plants yellow, orange, red and are therefore found in many orange-red vegetables. “But green vegetables such as spinach can also contain a lot of carotenoids,” adds the scientist, who is also researching the subject of vitamin A. In green vegetables, however, the orange-red color of the carotenoids is masked by the green plant substance chlorophyll.

The function of vitamin A.

Vitamin A is vital. “We need vitamin A for almost all body functions because it enables cells to differentiate,” explains Andrea Henze. This means that under the influence of this vital substance, the cell can become a skin cell, a mucous membrane or nerve cell. The other functions of vitamin A:

• Immune system: Vitamin A primarily promotes the development of lymphocytes and thus a strong immune response to foreign substances and pathogens.
• Skin and mucous membranes: It ensures healthy cell growth and cell integrity, thus preventing cracks and other damage, improving wound healing, i.e. regenerating. In this sense, vitamin A also acts on the lung epithelium and supports the constant renewal of the fine cilia that line the lung surface. It is similar in the intestine with the intestinal epithelium. Vitamin A is responsible for this constant renewal.
• Blood formation: Vitamin A promotes the formation of red blood cells (erythrocytes) and thus improves the transport of oxygen into every cell.
• Bones: It influences the storage of calcium phosphate in the bones.
• Reproduction and fertility: Vitamin A is extremely important for the formation of healthy egg cells and sperm as well as for embryonic development. “We know from studies that vitamin A deficiency in animals often causes infertility or, if fertilization does take place, the offspring can have deformities of the limbs,” adds the scientist.
• Seeing: Vitamin A is important in the eye as a pigment that enables the process of vision. It plays a key role in the nerve impulse that is triggered by the incidence of light and sent to the brain. Vitamin A, so to speak, mediates this signal cascade during the visual process.

Vitamin A does not have an antioxidant effect

From a purely chemical point of view, vitamin A is an antioxidant, but it does not play a role in the body in this context, for example because of its binding to transport proteins and its intracellular localization. As is often assumed, it is not a radical catcher and does not protect against “cell rust”, i.e. oxidation. “Vitamin A has no direct effect in this context, only an indirect one,” explains Andrea Henze more precisely: Vitamin A increases the absorption of vitamin E and selenium in the intestine, which have an antioxidant effect.

Pro-vitamins A such as beta carotene, on the other hand, can develop an antioxidant effect in the body before they are converted into vitamin A.

Why is this distinction important? Andrea Henze explains why it is best to use both animal and vegetable sources of vitamin A: Only then can the full spectrum of activity of these vital substances be used to the full.

Foods that are high in vitamin A and beta carotene

Among the foods of animal origin, the following are particularly rich in vitamin A:

• Beef liver
• Pork liver
• poultry
• butter
• cheese
• Eggs

When it comes to plant-based fruits and vegetables, these are good provitamin A suppliers:

• Carrots
• Cabbage
• spinach
• Apricots
• paprika

Store and prepare foods rich in vitamin A correctly

Vitamin A is sensitive to light, so food should be stored in the dark. In addition, the vital substance is relatively heat-stable and fat-soluble. This means that it is bound to fat and can therefore best be absorbed by the body.

In the case of animal sources, this is usually given or due to the preparation, for example the extremely low-fat liver is fried in oil. For the preliminary stage vitamin A, however, the corresponding vegetables should be prepared together with fat. “Studies have shown that it is particularly well absorbed by the body when it is crushed and steamed with a little fat,” reports Andrea Henze. Grinding is important so that the provitamin is released from the cellular structures.

An example: carrot vegetables, chopped up and steamed with a little safflower oil, provide the body with the vitamin better than nibbling raw carrots.

This is how much vitamin A you need every day

According to the reference value of the German Nutrition Society, the daily requirement for vitamin A is around one milligram per day. However, this is a bit simplified. Other units are used in nutritional science, the requirement is given as so-called retinol equivalents (RE) or retinol activity equivalents (RAE), explains the scientist and explains in more detail. 1 milligram of retinol corresponds to 1 milligram of RE or RAE. For provitamin A carotenoids, the calculation is more complex because additional factors have to be taken into account:

• Efficiency of absorption in the intestine (this is generally lower for carotenoids than for retinol or retinyl ester and depends on the food matrix)
• Conversion efficiency of provitamin A into vitamin A (this differs greatly between the provitamin A carotenoids, it is highest for beta carotene)

When using RAE, a conversion factor of 12: 1 is assumed for beta carotene and 24: 1 for all other provitamin A carotenoids. This means that 12 milligrams of beta carotene or 24 milligrams of other provitamin A carotenoids must be ingested with food to meet the requirement of 1 milligram of RAE. If, on the other hand, the intake takes place in the form of retinol or retinyl esters (i.e. from animal foods), the required intake is correspondingly lower.

According to this calculation, the daily requirement for vitamin A is covered with 150 grams of carrots, for example, or with a mixed diet: 1 egg, 100 grams of Gouda cheese and 75 grams of carrots.

Vitamin A deficiency affects certain risk groups

Because these foods are so rich in vitamin A, there is virtually no deficiency in this vital substance in Germany and other industrialized nations. However, that’s only true at first glance. Because experts differentiate between primary deficiency and secondary causes when it comes to undersupply.

Primary means that too few foods rich in vitamin A are eaten. This is almost never the case in this country. Even those who only eat fast food are adequately supplied with vitamin A. Vegans and vegetarians also get enough vitamin A from the preliminary stage.

It is different, however, with a secondary deficiency. In this context, secondary is used when the deficiency arises as a result of illnesses. Digestive diseases that affect absorption, such as:

• inflammatory bowel disease such as Crohn’s disease
• Celiac disease
• chronic liver disease, because vitamin A can then no longer be stored
• Diseases of the pancreas, because the digestive enzymes that are important for the absorption of the vitamin are not sufficiently produced.

In addition, there is a risk of undersupply if the vitamin A requirement is increased, this is the case with:

• pronounced inflammatory processes
• massive injuries such as burns when much of the skin surface is destroyed
• Kidney disease, which causes vitamin A to be excreted in the urine without being used
• Alcohol abuse because liver function is impaired
• pregnancy

Vitamin A Deficiency: Symptoms can be dramatic

As a rule, these risk groups are well looked after by a doctor, so that symptoms of deficiency rarely occur. Exception: alcoholics and very overweight people with massive fatty liver who do not seek medical advice. Apart from these patients, little is known about vitamin A deficiency in Germany. “Vitamin A deficiency occurs mainly in developing countries, where it is the main cause of blindness,” adds the scientist. Because one of the signs of vitamin A deficiency is night blindness, which can increase to complete blindness and is then no longer treatable.

There are also many other causes of night blindness, which are primarily age-related. The adaptive ability of the eye declines, for example as a result of cataracts, macular degeneration or retinopathia pigmentosa (hereditary disease). In any case, a doctor should always clarify if twilight vision deteriorates.

The other signs are a bit unspecific

• Susceptibility to infection
• dry skin and eyes
• brittle hair
• Loss of appetite
• Muscle weakness
• Fertility disorders

Vitamin A deficiency is best compensated for naturally

Anyone who thinks they are undersupplied with vitamin A should simply use more of the corresponding fruits and vegetables. Overdosing is not possible because the body only converts as much provitamin as it needs and it still makes sense to store it.

Over-the-counter supplements are the next step. It is best to get advice from a doctor and trust products from Germany. “Over-the-counter products only contain provitamin A, so overdosing is difficult, and absorption in the intestine is reduced if there is sufficient quantity,” explains Andrea Henze in more detail.

Beware of vitamin A supplements

Vitamin A supplements, on the other hand, can be more problematic, and poisoning is possible if overdosed. In Germany such products are therefore not freely available, but in other countries they are. “Vitamin A supplements should only be used under medical supervision and not for self-medication,” warns Andrea Henze.

Vitamin A poisoning – the first signs

The excess supply of vitamin A does not slow down the body, as is usually the case with provitamin A. The excess vitamin A is mainly stored in the liver; if it becomes too much, the detoxification organ can no longer work. “It leads to intoxication,” says the scientist. In pregnant women, this can also have negative consequences for the embryo.

The signs of vitamin A hypervitaminosis:

• Nausea and headache ,
• the bone tissue becomes porous.

If the oversupply lasts longer, it can even lead to death.

Incidentally, high doses of vitamin A supplements also led to the increase in lung cancer among smokers, previous studies warn.

There is no risk of intoxication from vitamin A through food – with one exception

What is certain is that over-the-counter supplements, which mainly contain beta-carotene, are usually harmless even if taken regularly. It is different with products that contain vitamin A, such as retinol. With them, intoxication is quite possible and can occur with a daily intake of 3 milligrams or more. By the way, retinol can also be found in many care products to keep the skin young and firm. “In this context, there is no need to fear overdosing, the substance does not pass from the skin into the bloodstream,” reassures the expert.

And hypervitaminosis A is hardly to be feared with food either. “Unless you eat liver several times a week,” warns Andrea Henze. Liver can contain over 30 milligrams per 100 grams of goods and thus exceeds the daily requirement by more than 30 times!

A historical anecdote shows how tragic this can end: More than 100 years ago, three researchers set out on an Antarctic expedition, Douglas Mawson, Belgrave Ninnis and Xavier Mertz. The expedition was not a lucky star, the men had to gradually eat the sled dogs in their distress in order not to starve to death. Mertz is said to have eaten the livers as well, subsequently complained of stomach pain, and his skin was partially peeling. After he fell into delirium, he passed away. Experts suspect that it was vitamin A poisoning from the dogs’ liver .

Therefore do not demonize the liver

Nobody knows for sure whether the story is really true. However, it is scientifically proven that hypervitaminosis A from natural foods is not to be feared, unless one eats a liver daily. Apart from that, the liver is an extremely valuable food from a nutritional point of view, contains vitamin A, iron, zinc , copper, vitamin B12 and folic acid, the supply of which is sometimes critical.

The most sensible recommendation: A lack of vitamin A can best be prevented with a balanced mixed diet, i.e. eat a lot of fruit and vegetables, whole grain and low-fat dairy products, sometimes a little fish or poultry.

It can be the cream you put on your face every morning, the beloved hamburger or a habit at the wheel – behind some everyday behavior lurks a danger that hardly anyone knows: you increase the risk of developing cancer. You should therefore leave the following things in the future:

1. Choose your window seat on the plane

Most people enjoy seeing the landscape from above during take-off and landing. Air travelers also like to look at the clouds of cotton wool under the clear blue sky. But if you fly often and sit by the window, you risk skin damage. The window panes keep out most of the UVB rays that cause sunburn. But they let through 47 percent of UVA rays. They are responsible for skin aging and a risk of skin cancer . Because: UV radiation can damage the genetic material. If damaged cells do not die, skin cancer can develop.

2. Insert all receipts

The receipts on thermal paper come from many cash registers and payment devices. And: bisphenol A (BPA). The substance has been classified by the EU as “of very high concern”. It endangers the brain development of the unborn, has been linked to male infertility, and can cause heart disease and cancer. Every time you touch thermal paper, BPA enters the body through the skin and accumulates there. In 2020, an EU-wide ban on thermal paper containing BPA will come into force.

3. Consume very hot drinks

Many people love their soup or tea steaming hot. But whoever swallows liquids above 65 degrees Celsius is putting his esophagus at risk . Because this irritates the tissue and in the long term cell damage occurs, from which cancer can develop.

4. Drive through the rush hour traffic with the window open

As long as there are no clean cars or driving bans in cities, diesel exhaust poses a specific risk for lung and bladder cancer. The WHO investigated this several years ago . Professional drivers or road construction workers are particularly at risk. But you can also get rid of dangerous diesel residues on daily trips through rush hour traffic with stop-and-go movement.

5. Avoid using condoms during sex

Those who live in a monogamous relationship will no longer be infected with the cancer-causing human papilloma virus. Because the greatest risk of HPV infection is unprotected intercourse with changing partners. The most common type of HPV cancer is cervical cancer, which usually develops many years after first exposure to the virus. Infection with certain HPV types can also lead to malignant tumors in the vagina, labia, anus and penis.

6. Use cosmetics with mineral oils

Oils care for the skin, but they shouldn’t be mineral oils. However, these are found in many cosmetic products, from skin cream to lipstick – for example when the ingredients are paraffin, petrolatum or mineral oil. The group of aromatic hydrocarbons (MOAH) poses a health risk. They have the potential to change the genetic makeup and cause cancer. They are filtered out of cosmetics – a decent residue remains, as the testers from the Stiftung Warentester found back in 2015.

7. Drink an after-work beer – or two, three …

Those who drink alcohol not only have an increased risk of liver cancer, but also of mouth and throat cancer and breast cancer. Unsurprisingly, this risk increases with the amount of alcohol. But there is no “safe” lower limit, especially for breast and liver cancer. Various substances that are produced when alcohol is broken down in the body probably play a role here.

8. Staring at your smartphone at night

Studies have shown a link between low levels of melatonin and a higher risk of cancer.The release of the sleep hormone is hindered when light breaks through the nighttime darkness . Smartphones and tablets are a common source of the bright glow in the dark bedroom nowadays. They delay falling asleep or wake the user with incoming messages that are immediately responded to. The sleep cycle is constantly interrupted and chronic sleep disorders develop – a risk factor for cancer.

If you don’t see a doctor, you won’t get cancer because of it. The regular check-ups and preventive appointments with the doctor but can ensure that a tumor early discovered no fatal cancer. The colonoscopy and cervical smear can even prevent abnormal cells from becoming cancer in the first place.

Stomach cancer is not uncommon, with around 15,000 new cases per year on the list of carcinomas. 9,300 men and 5,600 women are affected. The cause of the gender difference is currently unknown.

Stomach cancer is not one of the most common cancers, but the chances of survival are not good. Two thirds ultimately die of the tumor disease. “We have to assume that three out of four patients will only be diagnosed in a locally extended or even metastatic situation,” reports Michael Stahl, head of the Clinic for Internal Oncology at the Evangelical Clinics Essen-Mitte (KEM).

This late diagnosis means that three quarters of the patients have a poor prognosis and cannot be cured with an operation alone, summarizes the oncologist, who is among other things the author responsible for the German guideline for the diagnosis and treatment of esophageal cancer and a member of the lead group of the working group for internal oncology for carcinomas of the stomach and esophagus.

Cause of stomach cancer unknown but there are risk factors

“The only good relative risk factor for stomach cancer is the stomach germ Helicobacter pylori”, the expert clarifies. That would be risk factor number 1.

However, around a quarter of Germans are infected with this bacterium, but only a fraction of them develop gastric cancer. Why they get sick is not yet fully understood, just as much is still unknown about the causes of stomach cancer.

There is also evidence that smoking increases the risk. And what about alcohol? “However, there is no meaningful evidence that alcohol also increases the risk of stomach cancer,” adds the oncologist. However, it can lead to gastric mucosal inflammation, i.e. gastritis, up to and including gastric ulcer (ulcer).

Chronic gastric mucosal inflammation and reflux disease could in turn increase the risk of stomach cancer at the junction with the esophagus.

Stomach cancer can also develop from previous operations on the stomach.

The reflux of bile is also considered a risk factor. This danger arises from being very overweight.

And on the subject of obesity and nutrition: Scientists assume that a one-sided diet with a lot of processed meat products, heavily salted, but also smoked and grilled foods promote stomach cancer – keyword nitrosamines, which are known to be carcinogenic. Rotten and moldy foods pose a general health risk, also with regard to stomach cancer.

Stomach cancer with certain genetic changes

In addition, there are genetic components in the development of gastric cancer: first-degree relatives (children, siblings) of patients with gastric cancer have an increased risk – i.e. if the father, mother or sibling are ill. In addition, stomach cancer can occur if a certain form of colon cancer is already present (hereditary colorectal cancer) or breast cancer.

These are patients with changes in their genetic makeup, for example what is known as microsatellite instability (MSI). You are at an increased risk of various types of cancer, including cancer of the stomach and intestines. “Doctors should keep this in mind if a patient has a colon cancer with microsatellite instability , or if there are multiple carcinomas in the family,” emphasizes the Essen-based oncologist.

However, all of these are only possible risk factors. “Of most patients who fall ill, we don’t know why, because none of these risk factors apply to them,” summarizes Michael Stahl.

Look out for these warning signs

Besides this, there is the second difficulty in gastric cancer – late diagnosis. This is because the symptoms are rather unspecific, affecting the stomach, but are often dismissed as harmless everyday complaints. Early signs can be:

• Feeling of fullness, pressure in the stomach
• general upper abdominal discomfort
• Eructation
• nausea
• Vomit
• Flatulence
• Loss of appetite

“Anyone who has one or more of these complaints for more than three weeks should have them checked out by a doctor,” advises Michael Stahl.

Do not treat persistent stomach problems with acid blockers on your own initiative

However, many sufferers do not take these symptoms seriously and try to relieve them first with self-medication – wasting valuable time on early cancer therapy and thus a high chance of recovery.

They resort to gastric acid blockers that are available over the counter or prescribed by doctors. The pain will actually go away. “Cancer itself does not cause the pain at the beginning of the disease, rather the mucous membrane defect it causes is irritated by stomach acid – and that triggers the pain,” explains the expert.

This pain disappears when the stomach acid is blocked because it no longer irritates the mucous membrane. The cancer growth is not influenced by this, the tumor can spread undisturbed.

The most important diagnostic tool – gastroscopy

The oncologist therefore urgently recommends that the complaints be clarified by a quality-assured endoscopy, i.e. in a gastroenterological practice that carries out these examinations on a daily basis or in an appropriate center.

The gastroscopy only takes a few minutes; the doctor can not only check the condition of the esophagus and stomach up to the duodenum, but can also test whether Helicobacter is present and possibly take additional tissue samples.

Usually no tumor is discovered, but rather the stomach germ or an enlargement or relocation of the area between the stomach and esophagus (hernia), which can cause reflux. A change in diet can help here or medication may be necessary. Sometimes, however, the doctor finds stomach cancer, “and more and more often in the transition area to the esophagus,” reports the expert from the practice.

The reason for this is that there are more and more people who are very overweight. “Being overweight puts pressure on the abdominal cavity, which is why bile acids and stomach acids flow back into the transition area to the esophagus, which is not designed for frequent contact with these acids and is therefore damaged,” says Michael Stahl, summarizing the chain of reactions.

How stomach cancer spreads

The treatment depends on the severity of the disease (grading):

• Whether the carcinoma is limited to the mucous membrane,
• already affects the underlying muscle
• in addition, the outer connective tissue of the stomach
• surrounding organs
• Lymph nodes
• Has metastasized.

In Asian countries, where the risk of stomach cancer is very high and gastric cancer screening is therefore carried out regularly, the cancer can often be detected early. If the diagnosis “stomach cancer” is made in the early stages, i.e. only the mucous membrane is affected, there is a high chance of recovery.

Unfortunately, this is extremely rare in Germany, explains the oncologist. In this country, stomach cancer is usually only discovered when it has worked its way deeper into the tissue or has already broken through the stomach. This is also the reason why the prognosis for stomach cancer in Germany is so unfavorable – the cancer is recognized very late.

Stomach cancer does not depend on age

How long the time span between gastric cancer in its initial stage and the appearance of metastases cannot be answered. However, Michael Stahl points out in this context that it is a cancer myth that the tumor only grows slowly in the elderly. “We also have elderly patients with rapidly growing stomach cancer, and young ones,” he warns. Young people should also take stomach problems seriously and not dismiss them: “I’m only 35, it can’t be something bad, like cancer.”

Treatments for stomach cancer – chemotherapy plus surgery

Only in the early stages, i.e. when stomach cancer is limited to the mucous membrane, surgery alone is the method of choice. Then it is the only way to cure the patient.

Most patients, however, need more than the operation, the scientist reports. For locally advanced tumors (without metastasis), treatment consists of chemotherapy, surgery and renewed chemotherapy. Chemotherapy before the operation is intended to shrink the tumor and combat (invisible) metastases at an early stage.

Antibody therapy for HER2-positive gastric cancer

In addition, chemotherapy plus antibody therapy with so-called HER2 antibodies is used for certain forms of metastatic gastric cancer. In around 20 percent of gastric cancer patients, HER2 receptors (HER2-positive gastric cancer) are found in particularly large numbers on the cancer cells. They are docking points for growth factors. Occupied by the special antibodies, tumor growth can slow down significantly.

By the way, HER2 receptors are also found on breast cancer cells, keyword HER2-positive breast cancer. This is where this antibody therapy, which incidentally does not count among the immunotherapies, was first used.

In addition, attempts are being made in Germany, the scientist reports, to treat HER2-positive gastric cancer with HER2 antibodies plus immunotherapy. Scientists hope that this will enable them to offer equivalent treatment without chemotherapy in the future. However, the effect of this combination of therapies has not yet been proven.

Immunotherapies for gastric cancer do not (yet) meet expectations

In some forms of cancer such as melanoma or lung cancer, immunotherapies, for example with checkpoint inhibitors, are considered particularly successful today. These drugs are also currently being tested in studies for gastric cancer .

“Unfortunately, the first results are sobering,” reports the scientist. He and his colleagues had hoped that immunotherapy could improve the effect of chemo, but this was not confirmed. “If, however, all therapy options have already been exhausted in a patient, more can be achieved with immunotherapy than without further tumor-specific treatment,” reports Michael Stahl about the studies.

The problem with this is that it is currently difficult to predict in which patients the immunotherapy will work and which will not. Only in the few patients (less than ten percent of all patients with gastric cancer) whose tumors show what is known as high microsatellite instability (MSI-H) can one predict that immunotherapy has a high chance of effectiveness. Overall, the risk of severe side effects under immunotherapy is significantly lower than under chemotherapy, namely 20 percent instead of 60 percent.

The prognosis for gastric cancer is poor because the patients are late

How successful are the therapies at a glance? “The chances of a cure for stomach cancer are on average 25 to 30 percent; if stomach cancer is metastatic, the average life expectancy is one year,” reports Michael Stahl. The prognosis is only very good at a very early stage. However, patients with gastric cancer in this easily curable stage would be the exception in practice because many go to the doctor too late.

Prevention of stomach cancer – three measures

This makes provision and prevention all the more important. This includes, on the one hand, having longer stomach complaints clarified by a gastroscopy – and it does not matter how old the person affected is.

On the other hand, everyone should pay attention to the following three factors. Because little is known about the development of stomach cancer, so few are:

1. Pay attention to food hygiene, do not eat spoiled food, nothing that is moldy
2. Do not smoke
3. Avoid being overweight

This can not only protect the stomach, but is known to promote general health – not smoking and maintaining a normal weight are among the most important preventive measures against cardiovascular diseases such as high blood pressure, heart attack and stroke, but also against cancer.

Small bowel cancer accounts for up to five percent of all bowel cancers; around 2,600 men and women were diagnosed with small bowel cancer in 2016, compared with around 60,000 colon cancer. “It is important to classify a carcinoma on the one hand by localization, i.e. in the case of bowel cancer, small or colon cancer, but also differentiate it on the basis of its biological characteristics,” reports Ulrich Graeven, chief physician at the Clinic for Hematology, Oncology and Gastroenterology at Maria Hilf Mönchengladbach Hospital.

Cancer of the small intestine is usually biologically very different from cancer of the colon

While colon cancer is usually adeno tumors, i.e. growths of the mucous membrane, this affects only a small fraction of small bowel cancer. The most common forms of small bowel cancer, depending on the cells that cause the disease, are:

• Neuroendocrine tumors (NET) with around 50 percent, they arise from hormone-producing cells
• Gastrointestinal stromal tumors (GIST) make up about ten percent, these tumors originate from the connective tissue in the gastrointestinal tract.

The differing biological characteristics of the two types of colon cancer, colon and small bowel cancer, “make these two diseases so fundamentally different, even though both affect the bowel,” explains the oncologist.

Causes of small bowel cancer and why it is less common than colon cancer

What triggers the fact that the cells in the small intestine no longer act normally, but degenerate and multiply in an uncontrolled manner, is still largely unknown. It is assumed that there is a connection with pollutants in food that come into contact with the small intestine during passage and can thus influence its cells.

It is well known that the small intestine connects directly to the stomach. This first section of the three-part small intestine is called the duodenum, followed by the jejunum and ileum. In addition to transporting the chyme to the large intestine, the task of the five-meter-long small intestine is to break down certain food components and release them into the blood. The most important ones are carbohydrates, which are processed into various sugars, fat, but also vitamins and trace elements.

The chyme is still thin in this section of the intestine and is therefore transported on quickly. The contact time with the intestinal wall is much shorter than later in the large intestine, “which could explain why colon cancer is much more common than small intestine cancer,” the gastroenterologist explains the possible background. In addition, the mucous membrane in the small intestine is less susceptible to certain factors such as pollutants than that in the large intestine.

Risk factor hereditary diseases

However, there is also a familial willingness to develop small bowel cancer: Hereditary polyposis syndromes such as familial adenomatous polyposis (FAP) and Lynch syndrome. Genetically, a large number of polyps develop in the large intestine, sometimes also in the small intestine. These are adenocarcinomas, but are very rare in the small intestine compared to NET and GIST.

Small intestinal tumors associated with FAP are usually only discovered when polyps have been detected in the large intestine. In the course of further diagnosis of the familial predisposition, these rare small bowel carcinomas are also identified.

Small bowel cancer symptoms

Small bowel cancer usually grows slowly. Frequently, signs only appear when the disease has progressed and the tumor is taking up space. Depending on you can

• Bleeding,
• Stomach pain,
• nausea
• Constipation or diarrhea

occur. If the tumor is large, it can even block the intestines (ileus). The intestinal obstruction manifests itself through massive pain, it is always a medical emergency that is life-threatening and must be treated immediately.

Small bowel cancer prognosis varies

Small bowel cancer is usually only discovered at an advanced stage. In more than 70 percent, the carcinoma is only diagnosed in stage three or four, i.e. later than this applies to this common colon cancer – again the comparison with colon cancer.

The survival rates for small bowel cancer are therefore somewhat lower. “The decisive factor, however, is always the type of cancer of the small intestine,” explains the expert. If a GIST or NET is detected early, the chances of survival are very good. If, on the other hand, it is adenocarcinoma, which is also usually discovered later, the prognosis is not quite as favorable.

Diagnosis of small bowel cancer

The classic examination methods of gastroscopy and colonoscopy only cover the upper or lower part of the small intestine, “the almost five meters in between are not reached with these examination techniques,” explains the expert.

Imaging methods such as magnetic resonance tomography (MRT) or computed tomography (CT) are only used if there are symptoms and suspicion of this intestinal tumor. Capsule endoscopy, which shows images from the small intestine, also provides information.

Only when these examinations reveal an abnormality is it possible to specifically mirror the small intestine. “However, this is very time-consuming and cannot be used as a preventive examination – also because these intestinal tumors are very rare,” emphasizes Ulrich Graeven.

Small intestinal cancer therapies – surgery and its consequences

Overall, the following applies to the various small intestinal tumors: If possible, an operation should be performed. “If the tumor is limited, parts of the small intestine can usually be removed without any problems,” explains the oncologist in more detail.

A stoma, i.e. an artificial anus, is therefore usually not necessary. However, it is crucial which part of the small intestine is missing and which functions it had, which trace elements and vitamins it passed on to the body. This deficiency must then be compensated for through appropriate nutrition or medication.

Treatment for small bowel cancer varies depending on the type of tumor

Parts of the removed tumor are examined histologically. For the therapy plan, it is crucial whether it is NET, GIST or the rare familial adenocarcinoma in the small intestine. “A generally applicable therapy scheme for small bowel cancer is not possible because there is not just one small bowel cancer, but different ones, it always depends on its type,” emphasizes the oncologist.

Accordingly, there are many different therapy options. If a gastrointestinal stromal tumor (GIST) has metastasized, for example, there are very good drugs for further treatment. “This is not the classic chemotherapy, but we use so-called tyrosine kinase inhibitors, with very good results,” reports the expert. These are inhibitors, such as imitanib, that can block certain signaling pathways within the cells. They are sometimes also used before an operation to reduce the size of a tumor that is too large and therefore inoperable, or after an operation to avoid a relapse.

If the cancer of the small intestine is a neuroendocrine tumor (NET), on the other hand, surgery is often the only treatment required. The NET is further subdivided with regard to the need for drug therapy, taking into account its growth rate. This subdivision of the NET is also of crucial importance for planning therapy for metastatic NET.

Ademocarcinoma of the small intestine is treated on the basis of the results from the treatment of colon tumors.

Small bowel cancer prevention

Targeted prevention against these rare tumors is hardly possible – apart from the well-known rules for a healthy life, i.e. without smoking, with a sensible diet, extensive alcohol restriction and sufficient exercise. Because little is known about the possible causes of small bowel cancer, they cannot be influenced.

However, there is an important tip from the expert for everyone in whose families there are genetically determined polyps in the large intestine: Remember to not only limit the preventive measures to the large intestine, but also to extend it to the small intestine. Although this is provided for in the relevant colorectal cancer screening and follow-up programs, it must not be overlooked.

Biliary cancer, with around 5500 new cases per year, is one of the rare forms of cancer, but it is particularly risky. According to popular opinion, the tumor causes almost no early symptoms and is therefore usually only recognized late when an operation is no longer possible and the tumor has already metastasized.

Biliary cancer – important: inside or outside the liver

The fact is, however, that the colloquial term biliary cancer, medically cholangiocarcinoma (CCA), covers different forms. First of all, there is gallbladder cancer, which forms in the gallbladder, which in turn is embedded in the liver.

Secondly, a carcinoma can form in the bile ducts, which are not only located within the liver and direct the bile to storage in the gallbladder, but also away from the gallbladder, which lead the bile to the small intestine.

“Depending on the localization, we differentiate between intra- and extrahepatic carcinoma, i.e. those that develop inside or outside the liver,” explains Arndt Vogel, spokesman for the “Hepatobiliary Tumors” working group of the Internal Oncology Working Group (AIO) and head of the Visceral Oncological Center Hannover Medical School (MHH).

The risk of developing cholangiocarcinoma increases with age. Overall, the incidence of intrahepatic carcinomas is increasing, while that of extrahepatic carcinomas falls somewhat.

Risk factors for biliary cancer

An exception in connection with cholangiocarcinoma is Southeast Asia, especially countries like Thailand. This cancer often occurs there because certain parasites can inflame the biliary tract. Chronic inflammation plays an important role in the development of biliary cancer.

The following risk factors come into play in the western industrialized nations, but they are also closely related to inflammation:

• Primary sclerosing cholangitis, an inflammation of the bile ducts that mostly affects men.
• Cysts in the bile and bile ducts, including Caroli’s syndrome; they increase the risk of biliary cancer.
• Smoking, because the substances in smoke are known to be carcinogenic, are not only excreted via the kidneys and urine, but are also collected, processed and passed on in the bile.
• Gallstones; However, only when they cause problems, i.e. inflame the bile, do they promote the development of cancer.

Gallstones and biliary cancer

Around ten percent of Germans are said to have gallstones, and the risk increases with age. “But very few of those affected develop cholangiocarcinoma. This cancer is very rare, ”says the medicine professor reassuringly.

The gallbladder should only be removed if the stones cause problems, i.e. colic and inflammation.

Symptoms appear differently late, but are similar

The signs of gallbladder inflammation caused by stones are somewhat similar to those of cholangiocarcinoma (CCA).

So biliary cancer can cause the following signs:

• Jaundice (jaundice)
• nausea
• Vomit
• Pain in the left upper abdomen.

The location of the carcinoma is crucial for the stage at which symptoms appear:

• Intrahepatic carcinoma triggers these clear signs quite late, “because the liver doesn’t hurt when a tumor grows there,” explains the expert.
• Extrahepatic carcinoma, on the other hand, usually quickly means that the bile can no longer flow into the intestine. Bile congestion and jaundice are relatively early signs of this type of cancer.

That is why bile duct cancer that grows outside the liver is usually diagnosed earlier – but it is difficult to operate because of its often complicated location next to blood vessels and does not make the generally difficult situation with cholangiocarcinoma any easier, the oncologist limits the associated high expectations.

Diagnosis of cancer of the gallbladder and bile ducts

Doctors use cross-sectional image diagnostics such as MRI and CT. “This allows the suspicion to be clarified and the staging, i.e. stage and spread, to be identified,” explains Vogel.

The histological examination provides additional details about the tumor, whereby the samples in gallbladder cancer are relatively easy to obtain. However, this is more difficult with extrahepatic tumors because the biliary tract is often narrow and winding. The examination is carried out through an endoscope, the method here is called endoscopic retrograde cholangiopancreatography (ERCP examination).

Are there any less invasive methods? Ultrasound, carried out endoscopically through the stomach from the inside or from the outside, can also be informative, says the cancer specialist. However, the methods of first choice are MRI and CT.

Treatment of biliary cancer – surgery not always possible

If the suspicion has been confirmed and the results of the examination enable the tumor to be classified, the goal is to remove the carcinoma surgically. “However, as already described, this is sometimes difficult due to the location of the tumors,” reports Vogel. However, the surgical techniques have improved significantly in recent years.

The standard treatment for patients with advanced tumors is chemotherapy, with a combination of gemcitabine and cisplatin.

In a palliative situation, i.e. to lengthen survival time and / or improve quality of life, local therapies such as selective internal radiotherapy (SIRT, radioembolization) are currently used in clinical studies . Radioactive microspheres are guided to the tumor via an inguinal catheter, its cells are destroyed and healthy tissue is spared. The first results show that for some patients many months can be gained with this.

The prognosis for biliary cancer is poor …

Despite all these possibilities, few patients can be cured. Even if the tumor could be completely removed in the healthy, the recurrence rate is still relatively high. “60 to 80 percent of the tumors come back,” reports Vogel. Because the tumors spread very early.

… but with the therapy “a small revolution is emerging”

This is the bad news. In fact, these prospects could improve in the future. The oncologist says: “Because a small revolution is taking place here at the moment.” The interest of pharmaceutical companies in this rare cancer has increased significantly, and intensive work is being carried out on the development of new drugs.

The reason for this change is the fact that it has been discovered that numerous genetic changes occur in these tumors and thus allow a molecular, i.e. targeted therapy. There have been many studies on this topic for a few years now.

Two developments are particularly promising:

1. Inhibitors against IDH1 mutations , from which patients with a corresponding cholangiocarcinoma can clearly benefit.

2. Inhibitors against FGFR2 , fusions, MSI, NTRK and others.

“There are currently a number of very promising active ingredients in the test that have the various genetic changes as a starting point,” reports the oncologist. How much these new therapies could improve the treatment of biliary cancer becomes clear when one realizes that 40 to 50 percent of all these tumors, especially intrahepatic ones, show such genetic changes and are therefore suitable for targeted, molecular therapy.

Prevention Of Bile Cancer – Quit Smoking!

However, it will be some time before the new therapies are available to all patients. Until then, it is still true that biliary cancer is difficult to treat and the prognosis is unfavorable.

This makes prevention all the more important. To what extent can everyone prevent this tumor – apart from the advice not to smoke, which is so important with regard to many other diseases? The expert also has one recommendation in particular:

Get gallstones cleared up if they’re causing problems. However, this does not mean that everyone who has gallstones should be afraid: Gallstones are considered to be risk factors for gallbladder cancer, but only one percent of all gallstone carriers develop this tumor.