Introduction
Colon cancer is the second most common cancer in women and the third most common cancer in men. Like most other types of cancer, colorectal cancer is divided into different stages. This is done according to the so-called TNM classification.
The course of the disease depends largely on which tumour stage is involved. While intestinal tumours that are discovered at a very early stage have good to very good chances of healing, this can look different for a tumour that is discovered at a very late stage and has already spread (metastasised). The course of colorectal cancer is therefore very different.
The overall 5-year survival rate for colorectal cancer is just over 50%. This means that just over half of the patients are still alive 5 years after diagnosis. Life expectancy is strongly dependent on the stage of the tumour. In the early stage of the disease, i.e. stage I, about 95% of patients are still alive after 5 years. In the most advanced stage, stage IV, the 5-year survival rate is only about 5%.
This is how colon cancer is discovered
In colorectal cancer there is tumor growth in the area of the colon (colon carcinoma) or in the area of the rectum/rectum (rectal carcinoma). In most cases, colorectal cancer develops from a precancerous stage, the so-called intestinal polyps. It usually takes several years before a malignant tumour develops from a still benign polyp.
This is why screening plays a decisive role in bowel cancer. For this purpose, there are colon cancer preventive examinations which are financially covered by the statutory health insurance companies from the age of 55. Experts actually recommend to start such colorectal cancer screenings already at the age of 50, as from this age there is already a significantly increased risk of developing colorectal cancer.
A complete colonoscopy is performed during the colon cancer screening examination. In this procedure, a long, flexible tube with a camera at the end is inserted into the intestine via the anus and carefully advanced to the transition from small intestine to large intestine. The entire intestine is inspected by camera.
If conspicuous areas of the mucous membrane are discovered, small tissue samples can be taken using a pair of forceps. However, it is much more common for polyps to be discovered during preventive colonoscopy. Unless the polyps are very numerous or very large, they are removed during the colonoscopy.
They are then sent to a histopathological institute and examined under a microscope. The pathologist can then determine whether it is a benign tumour or whether malignant cells are already present. He can also see whether, in the case of malignant cells, the tumour has been completely removed or whether a new removal (resection) is necessary. In addition to the preventive colonoscopy, the annual digital-rectal examination, i.e. the palpation of the lower anal canal with the finger by the family doctor, and every 2 years a test for blood in the stool, are recommended from the age of 50 onwards as colon cancer preventive examinations.
