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Carcinoma of the stomach

Table of contents
Carcinoma of the stomach
Diagnosis carcinoma of the stomach
Forms of a carcinoma of the stomach
Stomach cancer therapy

Carcinoma of the stomach — the malignant tumor of a stomach developing from epithelial fabric.

Epidemiology
The carcinoma of the stomach on incidence and mortality is high on the list among all malignant new growths of the person. However its prevalence in various countries uneven. The highest incidence is observed in Japan (about 70 on 100 000 population), the smallest — in the USA (5 on 100 000).

Most often patients at the age of 60 flyings are surprised and are more senior. So, the carcinoma of the stomach on 100 000 population aged till 30 flyings meets at 0,7; 31 — 39 — 16,4; 40 — 50 years — 60; 61 years are also more senior — 360 people. According to aggregated data, the carcinoma of the stomach in 50 — 65% of cases is located in piloroantralny department, in 25 — 27% — on small curvature. The cardial department of a stomach (9%) and big curvature (2,9%) treat zones of rare localization. Multicentric growth of a cancer tumor of a stomach is observed in 2,2% of cases.

Etiology and pathogeny
The reason of development of a carcinoma of the stomach, as well as cancer in general, is not found out. Allocate the diverse factors contributing to development of a carcinoma of the stomach. Such environmental factors as features of the soil, composition of water, the maintenance of microelements in them concern to them. The risk of development of a carcinoma of the stomach increases at the frequent use in food of smoked fish and meat, is long the stored products, spicy and hot spices. Also food additives, first of all the nitrates used as preservatives are cancerogenic. Nitrates contain also in the vegetables which are grown up at excess of mineral fertilizers. Nitrates in itself do not lead to development of cancer, but become cancerogenic at transformation into nitrites. Transformation of nitrates into nitrites happens under the influence of nitratredutsiruyushchy bacterial flora which appears in a stomach at an intragastralny rn 5,0 and above. At the same time the products rich with ascorbic acid can play a carcinogenesis inhibitor role.

In development of a carcinoma of the stomach internal causes have a certain value. Higher incidence among the people having blood group 0(1) is noted. Primary and secondary immunodeficiences increase risk of emergence of malignant new growths. The carcinoma of the stomach in these cases is observed at persons at younger age. Cancer usually develops against the previous pathological changes of a mucous membrane of a stomach. According to WHO experts, it is necessary to distinguish precancerous states (conditions) and precancerous changes. The group of persons with precancerous states includes patients with the operated stomach, pernicious anemia, stomach ulcer. Refer proliferation disturbance (Menetriye's illness, adenomatosis), atrophic changes (chronic atrophic gastritis is more often), an epithelium dysplasia to precancerous changes.

Classification
Various classifications of a carcinoma of the stomach are offered: clinical and morphological.

Classification of stages of a carcinoma of the stomach, found broad application in clinical practice.
The I stage — the small, accurately limited tumor located in the thickness of a mucous membrane and a submucosal layer of a stomach is not present regional metastasises;
The II stage — the tumor which is growing into muscular layers of a stomach, but not sprouting its serous cover a stomach keeps mobility, in the next regional lymph nodes single metastasises;
The III stage — the tumor of the considerable sizes which is going beyond a stomach wall, accustoming to drinking and growing into the next bodies and sharply limiting mobility of a stomach, the same tumor or the smaller sizes with multiple regional metastasises;
The IV stage — a tumor of any sizes and any character in the presence of the remote metastasises.

The international classification of cancer approved at a meeting of the International anticarcinogenic union and WHO (Paris, 1965), is based on definition of extent of distribution of tumoral process prior to treatment with its designation on the TNM system (to tumor — primary tumor, nodulus — regional lymph nodes, metastasis — the remote metastasises).

T — Primary tumor
TX — is not enough data for an assessment of primary tumor
T0 — primary tumor is not defined
Tis — a preinvazivny carcinoma: an intraepithelial tumor without invasion of mucous own membrane (carcinoma in situ)
T1 — a tumor infiltrirut a stomach wall to a podsliznsty layer
T2 — a tumor infiltrirut a stomach wall to a subserous cover
The t3 — a tumor sprouts a serous cover (a visceral peritoneum) without invasion in the next structures
T4 — a tumor extends to the next structures
N — Regional lymph nodes
NX — is not enough data for an assessment of regional lymph nodes
There is no N0 — signs of metastatic defeat of regional lymph nodes
N1 — are available metastasises in perigastric lymph nodes (e) not further of 3 cm from edge of primary tumor
N2 — are available metastasises in perigastric lymph nodes (e) at distance more than 3 cm from edge of primary tumor or in the lymph nodes which are located along left gastric, the general hepatic, splenic or celiac arteries
M — the Remote metastasises
MX — are not enough data for definition of the remote metastasises
There is no MO — signs of the remote metastasises
M1 — are available the remote metastasises

Now it is accepted to allocate an early carcinoma of the stomach as it is possible to hope for successful treatment only at detection of a disease at this stage. Early cancer is understood as the small tumor (with a diameter up to 3 cm) which is located within a mucous membrane and a submucosal layer without penetration into a muscular layer of a wall of a stomach and in the absence of metastasises (T1N0M0 according to the WHO classification).

For convenience of cooperative researches and an assessment of results of treatment of WHO histologic classification is offered. Malignant epithelial tumors, according to this classification, are subdivided as follows:

1. Adenocarcinoma:
a) papillary;
b) tubular;
c) mucinous;
d) signet ring cell cancer.

2. Ferruterous and planocellular cancer.

3. Planocellular cancer.

4. Undifferentiated cancer.

5. Not classified cancer.


 
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