Check-up So reduce the colorectal cancer mortality

Colorectal cancer screening procedure: detect early stage cancer

Colorectal cancer is the third most common cancer in men and the second most common in women worldwide. The chances of a cure depend very much on how early the disease is diagnosed. An international panel of experts has now published a comprehensive review of colorectal cancer screening procedures. Therefore, stool tests and endoscopic examinations can significantly reduce the rate of colorectal cancer mortality.

Colon cancer accounts for ten percent of all new cancers

According to the German Cancer Research Center (DKFZ), colon cancer accounts for around ten percent of all new cancer cases worldwide. With rising incomes of the countries, the colon cancer incidence rates are also rising. The situation is different with the survival rates: Surviving in the affluent industrialized nations About 60 percent of those affected the first five years after a colorectal cancer diagnosis, so it is in the poor part of the world at most 30 percent of sufferers. It would be important to have an early diagnosis. Because early detection can save lives. But which cancer test is the safest? Both stool tests and endoscopic procedures such as colonoscopy can lower the rate of colorectal cancer, experts report.

Stool tests and endoscopic procedures such as colonoscopy can detect colon cancer at an early stage and thus reduce cancer mortality. (Image: psdesign1 / fotolia.com)

Recognize disease at an early stage

A series of screening methods is designed to detect colorectal cancer at an early stage, thereby reducing cancer mortality and the incidence of new diseases. But for which of the methods this has so far been sufficiently scientifically proven?

An international group of experts has now commissioned the World Health Organization (WHO) cancer research agency IARC to review the studies published on the different screening methods.

Michael Hoffmeister from the German Cancer Research Center (DKFZ) was also involved in the evaluation, which was published in the journal "New England Journal of Medicine".

Reduce colon cancer mortality

The IARC experts awarded the "adequately proven" or "limited evidence" predicates that a procedure actually reduces the incidence rate or mortality rate - or found inadequate or no evidence at all.

Proven to reduce bowel cancer mortality, the researchers classified the two chair-based examinations (immunological tests and the Guaiac enzyme test) - provided that they are performed regularly every two years.

Having also been sufficiently proven, the IARC experts evaluated the evidence that a single endoscopic procedure study reduces mortality:

These include the so-called "small colonoscopy" (sigmoidoscopy), which records only the last part of the large intestine, as well as the colonoscopy, in which the entire colon is inspected.

Endoscopic procedures and stool tests

On the other hand, according to the findings of the IARC researchers, the reduction in colorectal cancer incidence rates has so far only been sufficiently proven for the two endoscopic procedures.

Here are results from large randomized trials for sigmoidoscopy and numerous results from observational studies for colonoscopy.

"The results of four large randomized trials are still pending for colonoscopy. Nevertheless, in the opinion of most experts, a risk reduction for new cases has been adequately proven, since colonoscopy involves sigmoidoscopy and the overall intestinal reflection can be even more effective, "says Hoffmeister.

"For the immunological stool test, however, the study situation with regard to the reduction of the incidence rate is still insufficient. However, there is evidence that immunologic stool tests, if performed regularly every two years, can detect as many precursors and carcinomas in the gut as a single colonoscopy. "

Screening with computed tomography could not convince

In both endoscopic and stool testing, the benefits outweighed the risks of the study.

The previous study on the screening of the colon with a computed tomography, however, could not convince the IARC experts.

The IARC takes an international perspective with its assessments: "Not every country has the resources to offer all people involved in the screenings a costly examination, such as colonoscopy," explains Hoffmeister.

"Therefore, it is important to be able to recommend effective, more cost-effective procedures that are adapted to the performance of each healthcare system." (Ad)