Hereditary colon cancer is a disease that can be prevented successfully with proper monitoring. Lynch syndrome or colon hereditary nonpolyposis colorectal cancernis the most common inherited form, between 1% and 3% of all cases. A simple test within the tumor in all patients with colorectal cancer is better than any clinical recommendation to identify cases of Lynch syndrome, the most common inherited form of this cancer. Between two and three relatives of each diagnosed patient could benefit from preventive and monitory programs that prevent up to 80% of colon tumors.
The reearcher of IDIBELL and ICO Victor Moreno has participated in an international research, led by researchers from the Institute of Biomedical Research August Pi i Sunyer (IDIBAPS), Hospital Clinic and University of Barcelona, which proposes to conduct a specific test within the tumor in all colorectal cancer patients to identify Lynch syndrome, which is not currently covered by the implemented clinical recommendations.
The study, published in the latest issue of the Journal of the American Medical Association (JAMA), compares the effectiveness of two reference strategies for managing colorectal cancer known as Bethesda clinical guidelines and Jerusalem recommendations, with the application of a test (microsatellite instability and/or immunohistochemistry) that identifies patients carrying mutations associated with Lynch syndrome.
According to the authors, this is the largest sample ever used for the study of this syndrome, as it has gathered more than 10,000 cases, with samples from EPICOLON (Spain), Colon Cancer Family Registry (USA, Canada and Australia), Ohio State University (USA) and University of Helsinki (Finland).
The research, led by Dr. Antoni Castells, from the IDIBAPS-Hospital Clínic, has shown that a significant part of the syndrome will remain unidentified until the universal use of specific tests on the tumor in all patients diagnosed with colorectal cancer.
Improved diagnostic
The results revealed that the revised Bethesda clinical guidelines, dating from 2004, did not serve to detect the 12% of cases of Lynch syndrome. Also, the Jerusalem recommendations, that recommend doing the tests in all patients under 70 years, were insufficient in the 15% of cases.
Thirty thousand new cases a year
In Spain every year 30,000 new cases of colorectal cancer are detected. Up to 900 could be due to Lynch syndrome, most of which have not been properly identified. Moreover, for every case of Lynch syndrome detected can be identified two or three asymptomatic cases in the family, which would enter into a more comprehensive monitoring program that is used in the general population.
About 80% of mutation carriers will develop colon or rectum cancer, and the vast majority will do it before age 70. In these cases the prevention program includes a colonoscopy every year, an investment that prevents up to 80% of colon cancer cases due to this syndrome.
References: Moreira L, Balaguer F, Lindor N, de la Chapelle A, Hampel H, Aaltonen LA, Hopper JL, Le Marchand L, Gallinger S, Newcomb PA, Haile R, Thibodeau SN, Gunawardena S, Jenkins MA, Buchanan DD, Potter JD, Baron JA, Ahnen DJ, Moreno V, Andreu M, Ponz de Leon M, Rustgi AK, Castells A; EPICOLON Consortium. Identification of Lynch Syndrome among Patients with Colorectal Cancer. JAMA, 17 d’octubre de 2012.
Source: IDIBAPS / Agencia SINC