The etiology and pathogenesis of gastric cancer

For cancer of the stomach as the reason may be held all the same factors, which are modern Oncology for cancer in General; have a value of neuropsychiatric and direct food factors and diet. The issue of genetic influences remains in the sphere of speculative considerations.
The most common view is that stomach cancer develops on the background of past changes epithelium and all of the gastric mucosa. These changes are pre indefinite period of time, seldom do not manifest themselves, and often already before the cancer disturb the patient by various manifestations. With the help of repeated operations on the stomach is established that during 5-7-10 years or more, many of benign diseases of the stomach turn into cancer. They now join the group of the so-called pre-cancerous diseases of the stomach (Centners, Masevich, 1969; T. C. Shemyakin, 1969 and others).
First of all it should be called a polyp of the stomach, gastric ulcer, gastritis, alcohol consumption and gross annoying food, Smoking, etc.
Polina stomach trouble, no doubt, has a connection with the subsequent development of cancer in it. L. M. Ratner informs about 30-50% of malignization stomach polyps, V. S. Leviticus - about 46%, E. L. birch - about 30-33%, Century A. Melnikov, N. S. Timofeev - about 40-60%, Barret - about 12-50% etc.
According to N. N. Possible expansion (1963), histological examination of drugs after stomach resection about polyposis in 24.2% of cases there is a shift of polyps in cancer or has been a combination of cancer and polyps. In cancer often turn stomach polyps adenomatous buildings without inflammation, and with long-term inflammatory processes in them. Examples of when, after gastrectomy about the polyp in the cult of the stomach developed cancer.
Ulcers disease stomach should also be referred to the group of precancerous gastric lesions. Histological examination of drugs after gastrectomy about ulcers in 7-10% of cases is established transition ulcers in cancer. However, whether this is the cause of cancer it ulcer or associated gastritis - gastros hard to say.
According to A. S. Fedorov, based on a study of 500 products stomach obtained in the stomach resection for cancer in 10% of cases it has been proven tumour appearance of sores. A. Century Melnikov and N. S. Timofeev in 1947 established on the basis of data analysis 5707 resections for cancer of the stomach that 8.5% of patients in the cancer developed an ulcer.
Clinicians, particularly surgeons, bring large numbers regarding the transformation of the ulcer and stomach polyps in cancer; the therapists. Noteworthy data Geisendorfer (1957). He calculated that the frequency of turning kallusnoi stomach ulcers in cancer equal to 15%. Among isolated stomach polyps 51% of them turning into cancer; zlokacestvennosti polypous gastritis is calculated equal to 68%.
Chronic gastritis (or rather gastros) occurs in patients with gastric cancer in 97% of cases. Some researchers believe, however, that the relationship of gastritis and cancer has not been proven.
According to Schindler, patients with chronic gastritis in 3 times more likely to develop cancer of the stomach than healthy people of the same age.
A. Century Melnikov and N. S. Timofeev there are 3 variants of the relationship when discussing the role of gastritis in occurrence of a cancer of a stomach: 1) accidental coincidence, not dependent from each other processes (gastritis and cancer) in the same patient; 2) prior to the development of gastritis and possible by this predisposing "pre-cancerous" his role in the emergence of tumor growth, and 3) subsequent manifestation gastritises (religious) changes in the existence of the cancer. Cancer of the stomach against ahlorgidrii more frequent than on the background of hyperchlorhydria (70%).
C., Masevich (1969) has convincingly shown that to transform into cancer is most inclined to such chronic gastritis, which is characterized disregulatory process in the gastric mucosa. Acidity can not be drastically reduced. Agrees with this opinion, and So Century. Shemyakin (1969).
Therefore, there is every reason to believe in agreement with Century A. Melnikov (1960), chronic gastritis, polyposis and chronic (especially kaluzna) stomach ulcers are the intermediate stages of a single process, provided continuing action of carcinogens in the rest of the stomach. In this respect, the importance can play chemical composition of the food, industrial substitutes of food substances, Smoking and other irritating the mucous membrane of the agents to the environment. Deserve attention and autoimmune processes in the body of people who studied yet extremely insufficient.