Colonoscopy with your own hands
Starting from Monday, November 3, millions of people who have avoided colon cancer screening in the form of colonoscopy will have access to an alternative method for home use, which is not only non-invasive, but also does not require unpleasant preparations (cleaning the intestines with laxatives).
A new stool analysis test produced by Exact Sciences received approval from the U.S. Food and Drug Administration (FDA) last month. At first, Cologuard will be performed on a doctor's prescription only at the Mayo Clinic where it was developed. Subsequently, it will be available throughout the United States.
Many modern methods of stool analysis are based on the detection of blood contained in it, which may indicate the presence of an intestinal tumor. Cologuard detects not only blood, but also DNA associated with cancer cells, as well as precancerous neoplasms known as polyps. To do this, the patient only needs to send a stool sample to the laboratory.
If a positive result is obtained, the patient must undergo a diagnostic colonoscopy. This procedure consists in inserting a thin tube with a tiny chamber at the end into the large intestine and removing neoplasms for their subsequent histological analysis for the detection of malignant growth. The removal of polyps carried out in this way can prevent the formation of a cancerous tumor.
The best assessment of the effectiveness of the screening method is its ability to reduce the risk of death from the disease. In this regard, the effectiveness of Cologuard has not been confirmed to date. Direct comparison of the new method with the "gold standard" colonoscopy has not yet been carried out, but it is already being presented as an alternative to colonoscopy.
In a large clinical trial involving 10,000 people, the effectiveness of Cologuard was compared with the effectiveness of one of the old methods based on the detection of blood in the stool. As a result, Cologuard detected 92% of cases of rectal cancer and 42% of severe precancerous growth. For the older test, these values were 74% and 24%, respectively.
However, Cologuard has a drawback – a high probability of false positive results. The new method correctly indicated the presence of cancer in 87% of cases, while the old laboratory test – in 95% of cases.
On the one hand, the appearance of Cologuard may encourage people to abandon colonoscopy, the high effectiveness of which is confirmed by time.
On the other hand, the introduction of Cologuard into clinical practice can significantly intensify screening for a deadly disease, which many people currently consciously avoid for obvious reasons. In this regard, many experts agree that the best screening method is the one that people willingly agree to.
The main stages of using the kit are shown in the figure from the brochure intended for doctors,
and the rest, even without translation, is clear from the video, although everything is shown there not so realistically, but "on the fingers".
Article by Thomas F. Imperiale et al. Multitarget Stool DNA Testing for Colorectal-Cancer Screening is published in the New England Journal of Medicine.
Evgeniya Ryabtseva
Portal "Eternal youth" http://vechnayamolodost.ru based on the materials of Cologuard.
28.10.2014