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Colon cancer

The main principles of carcinogenesis of solid tumors were established by the example of colon tumors and form the basis for the study of tumors of other localizations. But even in the development of these quite well-studied tumors, various options are possible.

In the case of hereditary adenomatous polyposis, the patient has a mutation of the APC gene in stem cells, the formation of a clone of mutated cells. This leads to the formation of adenomatous polyps by about 16 years of age. The increased risk of malignancy in this case is due to a violation of genetic regulation and an early loss of control over cell proliferation processes. Moreover, each colon epithelial cell now has a given genetic defect, which increases the pool of hyperproliferating cells. The most important feature of the disease can be identified with a thorough history. In the absence of early diagnosis and treatment, the carrier of the defective gene usually dies at about the age of 42 years. In such patients, thousands of adenomatous polyps can exist in the intestines for a long time (25 years or more), but only a few of them are malignant. In the course of extensive observations, it was found that approximately half of the patients had only one malignant tumor, while in the majority of the remaining patients, approximately 7 malignant polyps were determined.
Thus, for the formation of cancer, only the formation of an adenoma is not enough, and additional genetic damage to the polyp cells is required.

An increased risk of developing colon cancer is in patients with ulcerative colitis. In general, genetic changes in ulcerative colitis are similar to those in cancer. At the same time, three most important provisions affecting the development of cancer are distinguished:

1. Mutation of the K-RAS gene in cancer with ulcerative colitis is rarely detected. Cancer with ulcerative colitis develops without activation of this gene, which is considered an important "intermediate event" in colon cancer and contributes to the clonal proliferation of precancerous cells.

2. Mutations of the p53 gene have a high frequency and occur early.

3. In intestinal epithelial cells with normal morphology, aneuploidy is often found, which predisposes to the further development of dysplasia and cancer.

Tumors with ulcerative colitis are formed according to a special "program" (they have their own very shortened intermediate stage), which leads to a quick, malignant process. The mechanism of these differences has not been studied. But, mainly, colon cancer with colitis occurs as a result of chronic inflammation, in contrast to sporadic cancer of a different etiology.
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Colon cancer

  1. Colon cancer
    The end of the twentieth century. was marked by a significant change in the structure of cancer incidence. In Russia, colon cancer (colorectal cancer) came in third place. The incidence of malignant neoplasms of the cecum and colon among men is 11.6, among women - 9.2 per 100 thousand adults, and rectal cancer - 11.0 and 7.1, respectively. Colorectal cancer is
    In the surgical treatment of cancer of the female genitalia, the rectosigmoid colon is often removed. Then, reconstructive operations are performed, such as removing the final section of the sigmoid colon or very low colorectostomy. After these operations, patients may experience undesirable frequent bowel movements, up to 6-8 times a day. Assigning opiates to solve this problem may
  3. Bowel disease. Infectious enterocolitis (dysentery, typhoid fever, cholera). Nonspecific ulcerative colitis. Crohn's disease. Coronary bowel disease. Appendicitis. Colon cancer
    1. Macroscopic characteristics of the small intestine with cholera enteritis 1. a gray-yellow film tightly adhered to the wall 2. ulceration of the mucous membrane 3. multiple hemorrhages 4. wall sclerosis 2. Elements of the pathogenesis of typhoid fever 1. bacteremia 2. bacteriocholia 3. cerebral swelling 4. exudative inflammation 5. hypersensitivity reaction in the lymphoid apparatus 3. Modern
    Colon cancer currently occupies the 3rd place among its other localizations and, according to various authors, makes up 98-99% of all intestinal cancers. Colon cancer is twice as likely to affect men than women. The most common tumor location is the sigmoid (25-30%) and, especially, the rectum (about 40%). All other parts of the colon are significantly affected by the cancer.
  5. P. POLYPES AND Tumors of the Large Intestine
    1. Benign polyps, polyposis and tumors. The etiology and pathogenesis, as well as tumors, in general, have not yet been sufficiently studied. Benign tumors (according to WHO, Geneva, 1981) are divided into three groups: 1). epithelial; 2). carpinoid; 3). non-epithelial tumors. Among the epithelial tumors of the colon, which make up the vast majority of all its tumors, distinguish
  6. Tumors of the small and large intestine
    Epithelial tumors make up the majority of intestinal neoplasms. Moreover, the colon, including the rectum, is one of the most common organ localizations of primary tumors. As an oncological cause of death for both sexes, colorectal cancer takes second place after bronchogenic carcinoma. The vast majority of cases of colon cancer are
    The purpose of this operation is the resection of the rectosigmoid colon and the reanastomosis of the colon and rectum with a single-row Gumbi suture. The physiological consequences. After removal of the rectosigmoid colon, the physiological consequences are minimal. If the patient received a course of radiation therapy in the pelvic area, then before performing a low anastomosis, it should be applied for 8-10 weeks
    The Strasbourg-Baker method involves applying a side-to-end anastomosis between the sigmoid colon and the rectal stump without shutting down the inferior mesenteric artery from the blood supply. It is also commonly used to preserve the anterior hemorrhoidal artery. An anastomosis according to Strasbourg-Baker can be formed with a manual seam or using a modern stapler (ACC). If
  9. Colon Cancer Screening Tests
    Screening tests are used to detect the asymptomatic course of the disease in apparently healthy people. To some extent, these tests are designed to increase a person’s life expectancy and improve its quality. An effective test should have sensitivity (optimal detection of patients), specificity (give a minimum of false positive results) and be accessible to a wide range of patients.
  10. Colon Syndromes
    Violation of the stool (frequent urge to defecate with small portions of feces containing mucus, sometimes blood, diarrhea can be replaced by constipation). • Pain (aching pain in the lower abdomen, less often colicky pain, lessening after defecation, gas discharge, worse after eating rough, greasy, fried foods). • Dyspeptic (bad taste in the mouth, belching with air, bloating).
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