Lynch syndrome is one of the most common hereditary cancer syndromes and the most common cause of inherited colorectal cancer (CRC) in the Unites States. An estimated one out of every 300 people could be a carrier. Given these statistics, it would seem that if testing is readily available (it is) and affordable (it is), it should be routinely performed (it isn’t).
More on Lynch Syndrome
Lynch syndrome is an inherited cancer syndrome associated with a genetic predisposition to different cancer types. These include not just CRC, but also endometrial cancer, ovarian cancer, stomach cancer, and more. Lynch syndrome is caused by a fault in a mismatch repair (MMR) gene and follows an autosomal dominant inheritance pattern. This means that a mutation needs to occur in only one copy of the gene for an individual to get Lynch syndrome.
While there are no symptoms of Lynch syndrome, there are red flags, including:
- Developing colorectal or endometrial cancer younger than age 50
- Colorectal cancer plus another Lynch syndrome-related cancer in one or more first-degree relatives before age 50
- Colorectal cancer in two or more first- or second-degree relatives with another Lynch syndrome-related cancer
People who have any of these warning signs should talk to their doctors about testing.
As mentioned, testing for Lynch Syndrome is not excessively complicated or expensive. And even if it were, it would be worth the trouble and cost. By age 50, people with Lynch syndrome have a 25% of getting CRC, and that number rises to 82% by age 70. But individuals who test positive for the syndrome can be proactive in screening for and preventing multiple cancers. For instance, by following recommendations for screening colonoscopies (every one to two years, beginning between age 20 to 25) a patient can lower the likelihood of getting CRC by up to 57% and reduce the chance of dying from the disease. In addition, a positive test result helps physicians optimize plans for surgery and chemotherapy and can prompt conversations among family members.
Lynch syndrome accounts for about 1 in every 12 case of colorectal cancer
in individuals younger than 50 years of age.
But back to the test. In essence there are two methods of screening: 1) a blood or saliva test to learn if an individual carries the mutation and 2) a screening test of cancer tissue to determine if Lynch syndrome is likely. The American Society of Clinical Oncology (ASCO) recommends that anyone diagnosed with colorectal cancer undergo tumor testing for Lynch syndrome at the time of diagnosis. This type of testing costs about $450 per case. Once Lynch syndrome has been discovered in a family member, relatives can be tested for the mutation. If positive, there is a 50% chance that parents, children, and siblings will also have this condition. Note that insurance typically covers Lynch syndrome genetic testing if it is determined to be medically necessary.
A CRC patient with Lynch syndrome has an average
of three relatives with the syndrome.
Physician Attitudes toward Lynch Syndrome Testing
Despite the availability of Lynch syndrome screening, physicians are not ordering it for a variety of reasons. A physician survey on barriers to testing suggests that doctors (mainly gastroenterologists) are concerned about testing costs, interpreting results, and a dearth of genetic counseling. Many are uncertain about which specialists (GIs or pathologists, for example) should order testing.
The study also showed that just 46.15% of respondents felt screening should take place before CRC surgery, even though having this information can help direct the extent of colonic resection. A related state-specific population-based study of early-onset CRC patients found that pre-operative screening was performed in just 23% of patients, and in those tested, results were available before surgery only 16.9% of the time.
Reversing the Numbers
Education is essential to increasing the frequency of Lynch syndrome testing. Providers need to know that screening costs are decreasing, insurance commonly covers testing, and testing companies often provide result interpretation and counseling services. In addition, clear testing protocols (and roles) should be established, and specialists involved in a case must communicate to confirm testing is complete and results are acted upon.
Although Lynch syndrome can alter the course of a life, it not a death sentence. Look at Selena Martinez. Since she was diagnosed at age 27, Martinez has been on a mission to inform her large, extended family about the risks of the syndrome and their options for screening. She also is vigilant about remaining cancer-free herself. Every year she has a colonoscopy and other screening tests for the cancers associated with Lynch syndrome.
Recently, she joined the efforts of Lynch Syndrome International to promote awareness of the disease and the availability of genetic counseling and testing services. "I want to make a difference in the lives of those with Lynch Syndrome," she says, "and hopefully with the advancement in technologies, the nature of the screenings will improve. I have an opportunity to beat cancer because I have the resources and advantages that family members before me didn't have. And for that, I am very fortunate.”