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Many people have polyps in their intestines. The older you get, the more common they occur. Intestinal polyps are protrusions of the mucous membrane that protrude from the intestinal mucosa into the inside of the intestine – the intestinal lumen. They arise because more cells than normal grow in one or more places in the mucous membrane. The polyps are typically found in the large intestine, especially in the last section, the rectum.
Most colon polyps are benign, so colon cancer will not develop from them. However, some polyps can develop into colon cancer over the course of years. Initially, a tiny polyp forms – a polyp bud. This can increase over time. For various reasons, the polyp tissue can become malignant, usually over a period of many years. The cells in the tissue grow in an uncontrolled manner. This is known as colon cancer.
How cancer can develop from polyps:
How does colon cancer develop from an intestinal polyp? An initially tiny increase in tissue – the polyp bud – increases in size over time. For various reasons, the polyp can become malignant. Then the tumor tissue grows uncontrollably and displaces healthy tissue. Colon cancer develops. This can spread into the underlying muscle layer, which is permeated by blood and lymph vessels.
Cancer cells can get to other parts of the body via the vessels and lead to more tumours (metastases). If the tumour is not discovered and continues to enlarge, it can completely fill the interior of the intestine and thus close it. If it grows outwards through the entire intestinal wall (breakthrough), other organs can also be affected directly.
There are different types of polyps. They differ in their shape and tissue structure (under the microscope):
Once the polyps have been removed, the adenomas – also called adenomatous polyps – further differ in their appearance into tubular, villous, and tubulovillous adenomas. Furthermore, adenomas can look like a sawtooth (serrated adenoma). However, the doctor cannot reliably differentiate these polyp forms from one another during a colonoscopy, so the classification is always based on removal under the microscope. This also means that any polyps discovered must be removed.
Few adenomas develop into colon cancer. Nevertheless, they represent a preliminary stage of colon cancer, as doctors call the type of tumour. Because in over 90 percent of cases, colon cancer develops from adenomatous polyps. The more adenomas there are in the colon and the larger they are, the higher the risk of cancer.
In some people, there is a large number of adenomas in the large intestine, which are hereditary. This clinical picture is called familial adenomatous polyposis (FAP). Without early cancer screening, almost 100 percent of these people develop colon cancer.
In most cases, intestinal polyps – especially small ones – do not cause any discomfort. It is rare for a polyp to bleed, which could be seen in the presence of blood in the stool. A larger polyp also rarely interferes with digestion. This could manifest itself as constipation, diarrhea, or a painful urge to defecate.
Colon polyps are usually discovered when the doctor does a colonoscopy. With the help of an endoscope – a kind of thin plastic tube – the gastroenterologist examines the inside of the colon. He can recognize polyps and remove them with a snare or forceps.
Even if most of these protruding mucous membranes are located in the rectum, experts recommend a complete colonoscopy – i.e. the entire colon. Because: If the doctor finds a polyp, more often occur. The colonoscopy is considered to be the best method to detect and prevent polyps and thus colon cancer.
Alternatively, there are tests for blood in the stool. You can recognize occult blood in the stool, i.e. blood that is not visible to the naked eye. The disadvantage: polyps can bleed, but don’t have to. That means: With this detection method, not all polyps and thus precancerous stages can be reliably identified.
The doctor removes colon polyps during the colonoscopy. He or she uses special instruments, such as a loop, that are inserted through the endoscope. The tissue is then examined in a laboratory to check whether it is benign or malignant. If the doctor determines that the patient already has colon cancer, he or she initiates appropriate therapy, usually an operation.
Colon polyps can develop again even if they were removed during the colonoscopy. The doctor will inform the patient when a check-up is advisable.
The risk of getting colon polyps can be reduced. The same recommendations apply here as for colon cancer.
Colonics are a great way to help keep your colon clean and support you in keeping up with a healthy lifestyle.