Gastric adenocarcinoma is a malignant tumor of the stomach originating from the cells of the glandular epithelium. At the initial stages, it may not manifest itself in any way, and therefore early diagnosis is difficult. In the future, epigastric pain, lack of appetite, nausea, belching, weight loss, weakness, apathy occur and progress. To confirm the diagnosis, EGS is performed with a biopsy, determination of cancer markers in the blood, stomach radiography, etc. The only radical method of treatment is surgical removal of the tumor. Radiation and chemotherapy are used as additional techniques or if there are contraindications to surgical treatment.
C16 Malignant neoplasm of the stomach
Gastric adenocarcinoma is a malignant tumor originating from the glandular epithelial cells of the stomach wall. This disease accounts for the vast majority of cases of stomach cancer and ranks first among oncopathology in many countries, including Russia, the Scandinavian countries, Ukraine, Japan. Often it is this pathology that is meant by the term “stomach cancer”. About 40% of patients turn to a gastroenterologist with an advanced stage, and in some cases, due to concomitant pathology, surgical removal of the tumor is impossible. At the same time, the mortality rate with radical treatment is about 12%.
Causes of gastric adenocarcinoma
The exact etiology of gastric adenocarcinoma is unknown. The cause of the development of this pathology is considered to be the long-term influence of carcinogenic agents against the background of inhibition of secretion and circulatory disorders. A number of factors predispose to the development of stomach cancer. The processes of malignancy have a genetic predisposition, depend on the characteristics of nutrition, a number of household factors. The association of the frequency of the disease with infection with Helicobacter pylori – a bacterium that causes gastritis and gastric ulcer (in patients with the presence of this microorganism, the frequency of stomach cancer is twice as high).
The incidence has age-related features: gastric adenocarcinoma is more common after 55 years. According to experts in the field of clinical oncology, men suffer from this disease three times more often than women. Smoking and alcohol play an important role in the development of the cancer process. The use of strong alcoholic beverages leads to the development of focal proliferative processes in the gastric mucosa, and eventually cancer.
Also, factors such as a diet low in dietary fiber, vitamins, antioxidants, pernicious anemia, chronic atrophic gastritis, adenomatous gastric polyp, hyperplastic gastritis are important in the development of gastric adenocarcinoma. Among the endogenous causes, the role of N-nitroso compounds synthesized in the stomach in various pathological conditions is not excluded. Their massive synthesis occurs in diseases with anacid condition.
Adenocarcinoma almost never occurs in a healthy stomach. In gastroenterology, precancerous (background) diseases and changes in the gastric mucosa are distinguished. Precancerous diseases include conditions that can potentially lead to the development of cancer: chronic gastritis, polyps, chronic ulcers, the part of the stomach remaining after resection, and others. Precancerous changes in the gastric mucosa include morphologically proven changes indicating the development of the process in the direction of malignancy (malignancy). These changes are combined by the term “dysplasia”.
The following types of gastric adenocarcinoma are distinguished:
- ulcer-cancer – tumor has the shape of a saucer with ulceration in the central zone;
- skirr – the pathological process spreads to most of the organ and penetrates deep into the gastric wall;
- polypoid cancer is a tumor with clear borders, visually resembling a polyp;
- pseudoalcer cancer – this form for a long time resembles the manifestations of stomach ulcers;
- tubular adenocarcinoma is a tumor of cells of cubic, cylindrical epithelium;
- mucosal adenocarcinoma is a tumor of mucinous (mucus-producing) cells.
According to the TNM classification, which takes into account the degree of infiltration of the organ, the lesion of regional lymph nodes and the presence of metastasis to remote areas, there are four stages of the disease. There is also a histopathological classification based on the degree of differentiation of cancer cells (high, medium, low degree, undifferentiated adenocarcinoma).
Gastric adenocarcinoma symptoms
The most common symptoms of gastric adenocarcinoma are pain localized in the epigastric region, the intensity of which is usually not associated with eating, nausea, vomiting, belching, lack of appetite. Stool disorders often develop – constipation, diarrhea. Characterized by weight loss, weakness, apathy. Of great importance is the identification of “small” signs (a feeling of discomfort in the epigastrium, loss of satisfaction from food, an unpleasant taste, fatigue, decreased ability to work, anemia).
The symptoms of the disease depend on the localization of the tumor, the nature of its growth, histological characteristics, changes in other organs. Usually local symptoms appear when the size of the formation interferes with the normal functioning of the stomach. In the presence of a tumor in the antral (exit) part of the stomach, a clinic of pylorostenosis (narrowing of the lumen of the pylorus) occurs. A tumor localized in the body of the stomach does not manifest itself for a long time, since the volume of the stomach is large enough. This form is usually detected when the neoplasm reaches a significant size and the first signs may already be symptoms of general intoxication.
When the cardiac part of the stomach (its upper part) is affected, increasing signs of dysphagia develop – it is difficult for the patient to swallow, it is necessary to chew food thoroughly and drink copiously. With a significant tumor size, the passage of liquid food is difficult. With the germination of a stomach tumor into neighboring organs, the development of distant metastases, the clinic can be diverse and depends on the localization of the lesion.
If gastric adenocarcinoma is suspected, an in-depth clarification of the anamnesis of life and disease is carried out. Detailed identification of specific symptoms, as well as “small” criteria, suggests a malignant lesion. The anamnesis of this disease is usually short, characterized by rapid progression of symptoms. During an objective examination, an oncologist carefully examines the areas of the most frequent metastasis of stomach cancer: the neck, liver, lungs, navel, ovaries. To clarify the diagnosis, differential diagnostics are used:
- Gastroscopy. Allows you to visualize a pathological focus, take tissue samples from suspicious areas for histological and cytological examination.
- Stomach radiography. It makes it possible to assess violations of the anatomy of the inner wall of the stomach. The signs characteristic of cancer are determined: a filling defect, a change in contours.
- Endosonography. To determine the degree of penetration of cancer into the stomach wall, nearby organs, lymph nodes, an endoscopic ultrasound examination is prescribed. During this test, it is possible to conduct a fine needle biopsy of a suspicious area (biopsy with ultrasound guidance).
- Blood test. A general blood test confirms the presence of anemia. A blood test is performed for cancer markers: CEA (cancer embryonic antigen), CA (cancer antigen).
- Histological examination. The detection of cancer cells in the biopsy is a reliable diagnostic sign. Determining the type of cells, the degree of differentiation allows you to determine the form of the disease, predict the course and make the optimal treatment regimen.
Computed tomography (CT), magnetic resonance imaging (MRI) for stomach cancer can detect a tumor, but the main purpose of these methods is to determine the damage to nearby organs, the presence of metastases in regional, remote groups of lymph nodes, liver, lungs and other organs. Tomography makes it possible to determine which method of treatment in this case will be most effective. Differential diagnosis of gastric adenocarcinoma is carried out with gastritis, ulcers (especially callous), as well as stomach polyps.
Treatment of gastric adenocarcinoma
The main and only radical method of treatment is surgery. Radiation and chemotherapy for this pathology as independent methods are used exclusively in cases of contraindications to surgery, as well as in the fourth stage.
The operation can be performed in two variants: gastrectomy (the entire stomach with regional lymph nodes, part of the esophagus, small intestine, and other tissues adjacent to the tumor are removed) or subtotal resection (part of the organ with the tumor and a small area of surrounding tissues are removed). The choice of tactics is determined by the size, localization of the tumor, its histological characteristics.
If, during a standard operation, the formation cannot be completely removed, but overlaps the stomach, causing significant digestive disorders, the following techniques can be applied:
- endoluminal stenting is the introduction of a stent (tube) into the stomach, which allows to preserve the lumen of the organ. It is carried out in order to ensure the patient’s ability to eat independently.
- endoluminal laser therapy is a method of endoscopic laser exposure in which cancer cells are removed by a laser beam like a knife.
Chemotherapy for gastric adenocarcinoma is not a highly effective method. It is used before surgical treatment in order to reduce the size of the formation and improve the result of treatment, or in case of contraindications or inexpediency of surgery to improve the patient’s condition. As an adjuvant treatment, it is prescribed in combination with radiation therapy after resection in order to destroy the remaining tumor cells.
Radiation therapy is also not used as an independent method. It is used in combination with surgical treatment, with contraindications to it – with chemotherapy. It is used to reduce symptoms (pain syndrome) as a palliative method.
Prognosis and prevention
The prognosis for gastric adenocarcinoma is determined by the stage of the disease, the localization of the tumor. Adenocarcinomas of the lower part of the stomach, the cardiac department usually have a better prognosis, because due to the peculiarities of the location, symptoms appear earlier, at earlier stages, when radical treatment is possible. The prognosis also depends on the histological characteristics of the cancer: the higher the degree of cell differentiation, the better the treatment result can be achieved.
In most cases, gastric adenocarcinoma is diagnosed at late stages, only 20% of patients are diagnosed at early stages. Late diagnosis significantly worsens the prognosis of the disease. Therefore, every patient being treated in the gastroenterology department, if potentially dangerous symptoms are detected, must undergo the necessary examination to exclude cancer. Prevention of stomach cancer consists in a rational diet, quitting smoking and drinking strong alcoholic beverages, limiting products containing preservatives, dyes.
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