Therapy
Colon carcinoma is divided into stages. The therapy then depends on which stage the tumour belongs to. The therapy of a colon carcinoma almost always involves surgical removal of the tumour or at least the largest possible part of it.
Depending on the location of the tumour, a distinction is made between numerous different types of resection (ways of removing the tumour). A distinction is made between, among other things, a resection of the left, right, or middle part of the colon and a removal of the sigmoid colon. Tumours located in the rectal area can be removed in a continence-preserving or non-continence-preserving manner.
This depends on their position in relation to the anal sphincter. Depending on the type of resection, the subsequent reconstruction procedures also differ. In the case of removal of the left, right or middle part of the colon, the parts of the colon before and after the resection are usually joined together (anastomosis).
In the case of resections in the rectal area, the reconstructions are sometimes more complicated. In addition to the affected part of the intestine, the associated lymph nodes are also removed, as the tumour may have spread here. Depending on the stage of the tumour, additional chemotherapy and radiation (radiotherapy) are used before and/or after the surgical resection.
Even in the case of colon cancer which is primarily no longer considered curatively treatable (i.e. for which a cure is not expected), the removal of parts of the tumour may be useful, among other things to allow the intestinal passage of food as far as possible and also to reduce complaints such as pain. In palliative therapy (i.e. a therapy which, due to the stage of the tumour, does not aim at a cure but rather at a reduction of symptoms), chemotherapy and newer therapy methods such as antibody therapy are also used. Aftercare after the treatment of a colon carcinoma must – especially at the beginning – be carried out at close intervals, since a recurrence of the tumour (relapse) occurs in about 70% of cases in the first two years after resection.
Follow-up examinations include ultrasound of the liver, colonoscopy, chest X-ray and laboratory tests to determine the tumour markers. The tumour markers usually drop significantly after a successful resection, so a marked increase may be an indication of recurrence. An artificial bowel outlet is also known as anus praeter, stoma or enterostoma.
It serves to drain the bowel movement directly through the abdominal wall and not, as in healthy individuals, through the rectum and anus. In an operation, the (usually) large intestine is detached from its holding structures in the abdomen and sutured to the abdominal skin. It is then cut, i.e. opened, so that the intestinal contents can drain into an external bag.
The bag can then be emptied or changed by the patient into the toilet. An artificial bowel outlet can be a permanent or temporary solution for a passage problem of the bowel. A permanent stoma is used, for example, if the sphincter muscle had to be removed in the case of deep-seated intestinal cancer.
A temporary stoma is performed if one wishes to maintain the continuity of therapy for intestinal cancer (e.g. by radiation). The artificial bowel outlet can also be used for other bowel diseases (e.g. chronic inflammatory bowel diseases such as Crohn’s disease or ulcerative colitis). The health insurance companies cover two preventive colonoscopies at intervals of 10 years for men and women over 55 years of age.
In view of the fact that the incidence (occurrence) of colon cancer increases significantly from the age of 50, a preventive colonoscopy should be viewed critically at the age of 55. In a preventive colonoscopy, the entire colon is observed using a tube to which a camera is attached. The tube is inserted from the rectum.
The patient must have drunk several liters of a laxative solution the day before so that the intestine is as empty, cleaned and well visible as possible. During the examination the patient is usually sedated, a short anaesthetic is used. If conspicuous protrusions of the mucous membrane (adenomas) are found, these are usually removed immediately during the examination using a small sling.
They are then histologically processed to determine whether it is a preform or an already manifest form of intestinal cancer and whether the adenoma has been removed at a sufficient distance so that there is no longer any pathological tissue in the affected intestinal section. If the screening colonoscopy was inconspicuous, another one can be taken after 10 years. If an adenoma was removed, the time until the next endoscopy depends on whether the adenoma could be resected with sufficient safety distance. The next colonoscopy is then performed after 3 months (complete resection of all abnormal tissue not safe) or 3 years (complete resection of the andenome).
