2024-02-09 00:33:47
The technique is based on the search, using liquid biopsy, for both tumor DNA mutations and DNA modifications (methylation) and fragmentomics linked to tumors. The work that validates it has been published in Annals of Oncology.
It has a sensitivity greater than 90% in tumors and 23% in preneoplastic polypoid lesions, prior to the appearance of the tumor. Although they have not been directly compared, their efficiency is similar to the test used in colon cancer screening, the fecal occult blood test for the diagnosis of colorectal cancer.
The team responsible for the work considers that this technique could serve to increase the participation of the population in screening programs, which now amounts to less than half of the people called to participate in them.
A team of researchers from the Hospital del Mar in Barcelona has confirmed the usefulness, in the context of screening programs, of a blood test with a performance comparable to the current colon cancer detection options according to international guidelines for detecting colon cancer. colon. The work, published in the journal Annals of Oncology, uses the liquid biopsy technique to detect tumor markers in peripheral blood. Members of the Digestive System, Oncology, Epidemiology and Evaluation and Pathological Anatomy services of the Hospital del Mar participated in it. The results were also presented at the congress of the European Society of Medical Oncology, ESMO, held in Madrid last month October.
The study has analyzed 623 blood samples, 318 from people who underwent a colonoscopy between 2017 and 2018 at the Hospital del Mar after the fecal occult blood test, the test used in the breast cancer screening program. colon, test positive. The rest were people who had been diagnosed with colon cancer. The test looks for DNA from the tumor in the colon, using different strategies simultaneously: it analyzes the presence of DNA mutations, methylations, as well as fragmentomics, that is, alterations related to the tumor, expanding the spectrum of possible markers. “The analysis of multiple markers allows us to increase the sensitivity in the detection of circulating tumor DNA, which in the most initial stages of the tumor may be very little present in blood samples,” explains Dr. Beatriz Bellosillo, head of the Diagnostic section. Molecular of the Pathological Anatomy Service.
In this way, “we move the liquid biopsy one step earlier than we have always used, to turn it into a useful tool to detect cancer in very early stages,” explains Joana Vidal, author of the study, associate physician at Hospital del Mar. and researcher at her research institute. It is the first time that liquid biopsy has been used in this context. “We want to go further, we want to go look for cancer before it shows its face,” adds Vidal.
Increase participation in the screening program
The work reveals that the blood test has a similar sensitivity to the test used in population screening in Catalonia, the fecal occult blood test, a test that is based on detecting traces of blood in feces. The two tests have high sensitivities, they detect more than 80% of cases, while their effectiveness in relation to lesions prior to tumors, preneoplastic polyps, drops to one in four cases. Likewise, a study has been completed with more than 20,000 people in the United States to confirm these results, using the same technology as the work of the Hospital del Mar. These data have been presented at the Digestive Disease Week congress (DDW2023) and have been submitted to the United States drug agency, the FDA, for evaluation.
The authors of the work trust that this new type of test would increase the participation of the population in the colon cancer screening program. The head of the Digestive System Service and coordinator of the Translational Research Group on Colon and Rectal Neoplasias at the Hospital del Mar Research Institute, Xavier Bessa, points out that “one of the basic pillars of any population screening program is to achieve maximum participation,” For this reason, “the search for a biomarker with high precision in peripheral blood, easy to obtain with a simple procedure such as an analysis, could favor it.” “It is a proof of concept of the usefulness of the biomarker, to facilitate the participation of the population with a simpler method, such as obtaining an analysis, and determine if adherence to the colon and rectal cancer screening program could be increased. “, Add.
At this time, the population screening program for colon cancer in Catalonia has not exceeded 50% participation of the population called to participate in it. A fact that affects its ability to detect tumors, especially in their initial stage. In this sense, “exploring new strategies to improve participation and efficiency of the tests used is a priority for population preventive programs, and this study is a very relevant step in this sense,” says Andrea Burón, section head of the Health Service. Epidemiology and Evaluation and researcher at the Hospital del Mar research institute.
Clara Montagut, head of the Digestive Oncology section at Hospital del Mar and also coordinator of the Colon and Rectal Cancer Research Group of her research institute, assures that improving the capacity of the screening program to reach more people “will have an impact on better cure rates, since the earlier we detect the tumor, the easier it is to treat and we increase the chances of cure.” In the study, “we have seen how liquid biopsy is capable of detecting colon cancer in very early stages, a fact that facilitates treatment.”
The study was carried out in collaboration with the United States biotechnology company, Guardant Health, responsible for the development of the test. The dibi Network for biomedical and imaging diagnosis, as well as researchers from the CIBER Cancer Center (CIBERONC), have also participated.
Colon and rectal cancer is the most common cancer among people over 50 years of age. In the State, it represents 15% of diagnosed cancers. It develops inside the large intestine from small lesions, which can be removed before a tumor develops.
#validate #liquid #biopsy #test #blood #detect #colon #rectal #cancer #Health #Medicine