Colon polyps and their transformation into colon cancer (colorectal carcinoma)

Approximately 10% of the population have sporadically occurring colon polyps, a trend that increases with age.

Along with hyperplastic (the second most common form) and serrated polyps (a special form of hyperplastic polyps), approximately 75% polyps are adenomas. According to the principle of the sequence of development of adenomas (adenoma-carcinoma sequencing), after years or decades, this leads to a malignant degeneration of the polyp. Therefore, polyps are known as precancerous disease.

Another disease is a rare genetically determined syndrome (familial adenomatous polyposis), in which hundreds of adenomas form in the intestines, as well as in the stomach and duodenum.

Approximately 6% of the population will develop bowel cancer during their lifetime, the most common malignancy. Colon cancer most often develops between the ages of 60 and 70.

Causes

Colon polyps occur sporadically, the degree of degeneration depending on the histological type and size of the polyp (increasing risk). To date, it is known that especially flat polyps in the right half of the colon most often degenerate into malignant tumors. Colon polyps occur for a variety of reasons. Serious risk factors are rich in animal fats, poor in fiber food. The risk of the disease increases with age, especially the family predisposition to the occurrence of polyps and malignant neoplasms.

Prevention

A measure to prevent the occurrence of cancer of the colon and rectum is to carry out a complete or, as they say, high colonoscopy, in which all parts of the colon are carefully examined up to the place where the small intestine passes into the large intestine. As part of this examination, all polyps can be removed using a so-called electroloop. This procedure, as well as the location of the polyp, is carefully documented.

During a detailed conversation with the attending physician, the patient will be fully informed about the possible consequences of this procedure, such as bleeding or damage to the intestinal wall. This procedure is the only way to prevent malignant degeneration of polyps in a timely manner. We recommend colonoscopy starting at age 50. Further frequency of examinations depends on the result of the examination and the result of the histological analysis of the polyp. Much less often, malignant tumors develop from the unchanged intestinal mucosa. They can be prevented with a healthy, vitamin-rich diet.

Symptoms

Small colon polyps often do not cause complaints, reaching large sizes they can clog the intestinal lumen or bleed. Malignant tumors lead to a change in the structure of the stool, for example, to alternating diarrhea and constipation, in addition, blood loss and anemia (anemia) appear as a lack of iron in the blood. Alarming symptoms are weight loss or complete intestinal obstruction.

Diagnostics

Diagnosis occurs with the help of colonoscopy, an endoscopic examination of the colon, which is carried out after the bowel cleansing procedure and is completely painless, thanks to the introduction of sedatives (sedatives) and painkillers.

If a malignant tumor is detected, tumor sampling will determine its histological type and growth rate of cancer cells. For further treatment, the location of the tumor is also crucial. A complete picture of the spread of oncological disease can be established only after removal of the tumor based on the study of the depth of tumor germination in the tissue, its germination in the lymph nodes and lymphatic vessels. It is very important to examine the patient's organs such as the liver and lungs, as well as the examination of the lymph nodes of the abdominal cavity.
An auxiliary factor, especially in the process of postoperative control over the patient, is the regular determination of the CEA tumor marker (cancer-embryonic antigen).

Treatment

Polyps can be removed endoscopically or, if large, surgically. Colon cancer, if it is located above the level of the rectum, is well treated with surgery, and the lymph nodes are also removed. Decisive for conducting postoperative prophylactic chemotherapy is the rate of tumor growth, the degree of depth of tumor germination, and the defeat of the lymph nodes. This therapy is now well tolerated by patients.

In case of damage to the rectum, preoperative radiation and chemotherapy are sometimes necessary. This allows you to save the obturator muscle (anal sphincter) and at the same time operate on the patient so that the tumor is removed within healthy tissues. Therefore, it is better to carry out this combination therapy before surgery.

If a malignant tumor is located in close proximity to the anus, it is often necessary to perform an operation with the imposition of an unnatural (artificial) anus in order to remove the tumor within healthy tissues and prevent its further spread. If the tumor of the rectum is in the initial stage, it can be removed from the anus (without an incision in the abdomen). To do this, using sonography (ultrasound) of the rectum, it is necessary to establish that the tumor does not grow into the intestinal mucosa.