Lynch syndrome is a genetic disorder. People with this condition are at a higher risk for developing certain types of cancer, particularly of the colon. Approximately 140,000 cases of colorectal cancer are diagnosed every year, and three to five percent of those cases cite Lynch syndrome as the cause, according to the National Institutes of Health. Lynch syndrome is also known as hereditary nonpolyposis colorectal cancer (HNPCC).
Increased Cancer Risk
The most common types of cancer that people with Lynch syndrome tend to develop are colorectal and endometrial cancer. Although this disorder does not generally lead to non-cancerous polyps or growths in the colon, some people may develop them. Other diseases associated with Lynch syndrome include cancer of the
- Stomach
- Small intestine
- Liver
- Gallbladder
- Urinary tract
- Ovaries
There are No Symptoms
There are no overt symptoms associated with Lynch syndrome. Signs and symptoms, rather, point to the cancer that develops due to the disorder. According to the Genetic and Rare Diseases Information Center at NIH, 80 to 90% of people with Lynch syndrome who develop cancer will experience abdominal pain, constipation, fatigue, gastrointestinal bleeding, or weight loss.
Lynch Syndrome Genetics
Lynch syndrome is caused by a gene alteration in a mismatch repair gene. When the DNA in certain genes signal cells to grow and divide, mistakes are normally corrected automatically in the genetic code. The abnormal genes affiliated with Lynch syndrome cannot recognize and repair any errors that occur. When too many mistakes are not caught, genetic damage occurs that can lead to cells becoming cancerous.
The Role of Family History
If one has a family history of colon cancer, especially in members under 50, a gene for Lynch syndrome may be the culprit. A history of endometrial cancer or other related types can also point to the presence of this disorder.
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Speaking to a Physician
A family history of colon or endometrial cancer is something about which individuals should speak to a doctor. A family member may have already been diagnosed with Lynch syndrome, making it even more imperative to have this discussion preemptively.
Genetic Testing for Lynch Syndrome
When a person or their relative is diagnosed with cancer, the doctor can perform certain medical tests to determine whether Lynch syndrome is the cause. A test of colon cancer cell samples from tumors can identify genes affiliated with the disorder. Doctors may employ the following tests:
- Immunohistochemistry (IHC): Special dyes stain the samples. The staining will show whether missing proteins indicate mutated genes that can cause cancer.
- Microsatellite Instability (MSI): This test procures DNA sequences that show errors in the tumor cell sequences.
Treatment For Lynch Syndrome-Related Cancer
The most common type of cancer related to Lynch syndrome is colon cancer, followed by endometrial cancers. For people with the former, doctors will often recommend surgery to remove more of the colon than is usual with non-Lynch syndrome colon cancers. This is because of the heightened risk for recurrence in people with the disorder. The treatment will also likely include chemotherapy and radiation therapy.
Cancer Screening Plans
Doctors can devise in-depth cancer screening plans for those who know they have Lynch syndrome. The types of screenings recommended depend on the family history of disease and the particular gene that is at the root of the syndrome. Undergoing periodical tests to rule out colon, endometrial, ovarian, urinary system, or gastrointestinal cancers helps catch the disease early, reducing severity and fatality, should they develop.
Reducing Cancer Risk
When someone knows they have Lynch syndrome, a doctor might recommend preventative surgery to reduce their risk of developing cancer. Individuals may opt to have organs such as the ovaries and uterus removed to eliminate the possibility of endometrial cancer. For those who do not want to have frequent colon cancer screenings, the colon can be surgically removed (colectomy) to greatly reduce the likelihood of colon cancer without the need for a colostomy bag.
Living with Lynch Syndrome
Lifestyle changes can also help prevent the risk of cancer in people with Lynch syndrome. Diagnosed individuals should understand and watch for the symptoms associated with cancers linked to the cancers to which they are most susceptible. A healthy lifestyle, including eating plenty of leafy greens, avoiding processed foods, and exercising often, can also lessen the risk of cancer.