Colon, ovarian, uterine, gastric, renal, and skin cancer. All Lynch syndrome related cancers, and all significantly increased in families with Lynch syndrome mutations. Brain and small bowel cancer risks are also higher.
In addition, new evidence finds that pancreatic and breast cancer are also part of Lynch syndrome.
Today, people living with Lynch syndrome come together with researchers, genetic counselors, and healthcare professionals to spread the word that Lynch syndrome can be managed. But first it needs to be recognized.
Awareness saves lives.
Careful family histories and routine testing after surgery can identify people who have one of the genes that cause Lynch syndrome. When you find one affected person, you can also find family members who also carry the gene.
Lynch syndrome makes individuals significantly more likely to get colorectal cancer — 60 to 80 percent in their lifetimes. Endometrial cancer is also increased with a 40 to 60 percent lifetime risk. The cancers arise when DNA mismatch repair genes are mutated and fail to fix DNA mistakes made during cell division. Not only do cancers occur more frequently, they often appear at a younger age.
What can individuals do?
Learn your family medical history. Who has been diagnosed with cancer? When?
Know the 3-2-1 rule of thumb:
- Three individuals in one family diagnosed with a Lynch cancer — at least one a first-degree relative of another.
- Lynch cancers in two generations.
- At least one individual diagnosed under the age of 50.
Talk to a genetic counselor about your own and your family’s risk.
If your risk is high, get genetic testing to look for one of the Lynch genes: MLH1, MSH2, MSH6, PMS2.
If you carry one of those genes:
- Follow recommended surveillance plans including colonoscopy every 1 to 2 years.
- Let your close family members know so they can be tested too.
What can surgeons and pathologists do?
- Screen the tumors of all newly diagnosed colon cancer patients for microsatellite instability. Immunohistochemical testing can find if proteins expressed by Lynch genes are missing and which genes those are.
- Refer patients identified as possibly carrying a Lynch syndrome gene for genetic counseling and DNA testing to either confirm or rule out LS.
What can family doctors do?
- Review family history of all their adult patients.
- Use a simple online tool to estimate Lynch syndrome risk.
- Refer patients at risk for Lynch syndrome for further genetic counseling and DNA testing.
For more information about Lynch syndrome, watch Does Colorectal Cancer Run in Your Family with Dr. Henry Lynch.