National statistics on colorectal cancer are shocking: More than 150,000 new cases are diagnosed each year. It is the third most common type of cancer in both incidence and mortality and a cause can not be identified in 80 to 90% of cases. A statistic has a special importance and can help people who have a special risk of suffering from this disease. 5% of colorectal cancers have a clear genetic abnormality that can be hereditary.
Today there is the opportunity to perform genetic analysis and this can save lives. Through appropriate analyzes, patients and their family members can avoid the development of colorectal cancer. Colon and rectal cancer not associated with polyps (HNPCC) is the best studied of genetic colorectal cancers and while the average age of diagnosis of colon cancer is 63, the average age of diagnosis of HNPCC is 44.
Clinical criteria have been established to identify patients and family members who are at risk for HNPCC, also known as Lynch Syndrome. A key selection criterion is to have three or more family members diagnosed with colorectal cancer. The members of the family must be under 50 years of age and belong to two different generations. Other associated cancers, such as endometrial and ovarian cancers, may increase the risk of developing Lynch syndrome.
Genetic analyzes identify families at risk of developing hereditary cancers; they also prevent the development of malignant tumors. Doctors recommend individuals with a family history of colorectal cancer to begin controls at age 40, which is 10 years before the time when controls should begin normally. If a strong family pattern is suspected, genetic analyzes identify the specific genes responsible for hereditary cancer. Cancer biopsy samples can also indicate if it is possible that it is a hereditary cancer. If suspicious genes are identified, other members of the family can be analyzed to see if they are carriers. Those with genetic mutations begin a program of intensive controls and colonoscopies are performed every one or two years.
Consult a colorectal cancer specialist if you suspect that you have a genetic risk of developing this type of cancer and schedule your colonoscopy according to the established guidelines.
Dr. Hoffman does not endorse any of the products that appear on this website.