In most cases, a stomach tumour develops in the stomach lining. It originates 95% from cells of the glandular tissue. Doctors also refer to these classic stomach carcinomas, which originate from the glandular cells, as adenocarcinomas.
In rare cases, however, gastric tumours can arise from other cells in the stomach, such as the
- Cells of the lymphatic tissue (MALT lymphomas) or
- Cells of the muscle or connective tissue of the stomach wall (sarcomas or gastrointestinal stromal tumours (GIST)).
The stomach is a tubular to sac-shaped hollow organ belonging to the digestive tract. It is located in the left upper abdomen below the diaphragm and between the spleen and liver. At its upper end, the oesophagus flows into the stomach. At the lower end, the stomach passes into the duodenum.
The task of the stomach is to absorb the ingested food and to initiate the first digestive steps. With the help of the gastric juice, the food pulp is prepared for further digestion in the intestine and then passed in portions to the duodenum.
The stomach is divided into five different sections. Thus one distinguishes
- the oesophageal orifice(cardia),
- the stomach vault below the left diaphragm (gastric fundus),
- the body of the stomach (corpus),
- the section before the stomach outlet (antrum) and
- the gatekeeper muscle at the stomach outlet to the duodenum (pylorus), which controls the release of the food pulp to the intestine.
The two to three millimetre stomach wall is composed of four layers, namely
- the gastric mucosa,
- a layer of connective tissue,
- a muscle layer and
- the peritoneum that surrounds the outside of the stomach.
The position of the stomach in the human body © peterschreiber.media | AdobeStock
According to the Robert Koch Institute, around 17,000 people in Germany develop stomach cancer every year. Stomach cancer develops slightly more often in men than in women. Gastric carcinoma is thus the sixth most common tumour in men and the eighth most common tumour in women.
Mostly people in old age are affected. The mean age of onset is 69 years for men and 72 years for women. Middle-aged people are significantly less likely to develop stomach cancer. Young adults and children are hardly ever affected.
The number of cases of stomach cancer has been decreasing in Germany for more than 30 years. But despite these declining numbers of cases, stomach cancer is one of the most frequent tumour-related causes of death. This is mainly due to the fact that stomach cancer is usually detected too late.
The exact causes and connections that lead to the development of stomach cancer are not yet clearly understood. However, there are some known risk factors that favour the formation of a malignant stomach tumour. In particular, this includes
- a range of stomach disorders,
- certain eating habits and
- a genetic predisposition.
Stomach diseases that are associated with an increased risk of stomach cancer include the following
- Inflammation of the gastric mucosa (gastritis) caused by the bacterium helicobacter pylori,
- recurrent and poorly healing stomach ulcers,
- adenomatous gastric polyps and
- chronic atrophic autoimmune gastritis, a form of stomach inflammation caused by the body's own defence system (autoimmune disease).
In addition, previous stomach operations can also increase the risk of stomach cancer.
Dietary habits and lifestyle also play a role. For example
- the frequent consumption of heavily salted, cured, smoked or heavily grilled foods,
- a low consumption of fresh vegetables and fruit, and
- excessive alcohol consumption and
increase the risk of developing stomach cancer.
A genetic predisposition to stomach cancer is present if there are increased cases of stomach cancer in the family. If a first-degree relative, i.e. parents, children or siblings, has stomach cancer, their own risk of developing the disease is also increased.
In the early stages, gastric carcinoma usually causes no symptoms at all or only very unspecific symptoms. Stomach cancer is therefore often discovered late. The uncharacteristic symptoms that may occur at the beginning of the disease include
- a feeling of pressure in the upper abdomen,
- Bad breath,
- Black coloured faeces
- Unintentional, severe weight loss,
- Slightly elevated body temperature,
- Night sweats,
- Difficulty swallowing,
- Anaemia and
- a sudden aversion to certain foods, typically meat,
indicate gastric carcinoma.
If stomach cancer is suspected, several examinations are necessary to confirm the diagnosis. In the first step, the patient's medical history is taken as part of the so-called anamnesis. The doctor will ask questions about the exact symptoms as well as about diet and lifestyle.
The next step is usually a gastroscopy also known as a stomachoscopy. This allows the doctor to look at the stomach from the inside and thus detect changes in the stomach lining. During the gastroscopy, a tissue sample (biopsy) is taken if there are any abnormalities. It is then examined for malignant cancer cells under the microscope in the laboratory. If malignant, degenerated cells are detected, the diagnosis "stomach cancer" is made.
How a gastroscopy works © bilderzwerg | AdobeStock
Following the diagnosis, the doctors have to find out,
- how deeply the cancer cells have already penetrated the stomach wall, and
- whether the stomach cancer has already spread beyond the stomach.
Further investigations are therefore needed. By means of endoscopic ultrasound (endosonography), one determines
- the depth of tumour penetration into the stomach wall and
- the presence of metastases in the regional lymph nodes.
Tumour derivatives in other organs, so-called distant metastases, can be detected by means of Computer tomography (CT) or Magnetic resonance imaging (MRT) can be searched for. Most often, these are located in the abdomen and chest.
A finely nodular tumour seeding in the abdominal cavity is searched for and hopefully excluded by means of laparoscopy.
The treatment of stomach cancer is usually carried out by specialists from the medical fields of internal oncology and oncological surgery.
These have various treatment methods available for the treatment of gastric cancer, including
Which treatment method is used depends primarily on the stage of the disease.
Surgical treatment of stomach cancer
Surgery is the most important treatment option for stomach cancer. It comes into question when
- the stomach tumour can be completely removed and
- the stomach cancer has not yet spread to other organs.
Aim of the Stomach cancer surgery is to surgically remove the tumour and all cancer cells.
The extent of the operation depends on the size and type of stomach tumour. In some cases, the stomach only has to be partially removed, in others completely, in order to eliminate all cancer cells.
In addition, the surrounding connective tissue and the lymph nodes must also be cleared out precisely and radically (so-called D2 lymph node dissection). The surgeon has a crucial prognostic role. He should therefore have appropriate caseloads, training and experience.
Chemotherapy for stomach cancer
Chemotherapy aims to kill the cancer cells using cell growth inhibiting drugs, also known as cytostatics. It is often used as an adjuvant to surgery for stomach cancer. If it is given after surgery as part of the treatment plan, it is also known as adjuvant chemotherapy.
In the case of locally and regionally advanced gastric carcinomas, chemotherapy is also administered neoadjuvantly, i.e. before surgery. The aim is then to reduce the size of the stomach tumour so that it can be removed more easily, or at all, by surgery.
If metastases have already formed in other organs, a cure is no longer possible. In this case, chemotherapy only serves to slow down the tumour growth for a certain period of time and to alleviate the symptoms.
This type of treatment for stomach cancer is also known as palliative chemotherapy.
Radiotherapy for stomach cancer
Radiotherapy is considered for stomach cancer when
- the stomach carcinoma is inoperable and/or
- the tumour does not respond to chemotherapy.
The main aim of radiotherapy is to reduce the size of the stomach tumour and metastases in order to relieve pain.
The treatment of a patient with stomach cancer belongs in the hands of specialists in stomach cancer. It should be done in hospitals that have extensive experience with stomach cancer.
The German Cancer Society certifies these oncological treatment centres, which ensures high quality care for patients with stomach cancer.
Experts for stomach cancer are specialists from the fields of
These experts discuss their patients' individual cancers in tumour conferences. In doing so, they jointly develop a treatment strategy adapted to the patient, taking into account current guideline recommendations.
Specialists for stomach cancer are very familiar with all diagnostic and therapeutic procedures. They can demonstrate this through corresponding case numbers and performance records.