The vast majority of individuals with a diagnosis of colorectal (and/or endometrial/uterine) cancer do not have a inherited gene mutation. Most cancers develop sporadically without any familial association. However, if you or members of your immediate family have been diagnosed with colorectal and/or endometrial (uterine) cancer, you may be at risk of carrying a genetic mutation (called, “Lynch Syndrome” or “Hereditary Nonpolyposis Colorectal Cancer” or “HNPCC“.)
HNPCC/Lynch syndrome is reported to be present in up to 4% of all individuals diagnosed with colorectal cancer and in up to 5% of all women who have been diagnosed with endometrial (uterine) cancer.
Carriers of the HNPCC/Lynch Syndrome gene mutation have an increased risk of developing:
- Colorectal cancer (lifetime risk: 35-82%)
- Endometrial/uterine cancer (lifetime risk: 34-71%)
- Stomach cancer (lifetime risk: up to 13%)
- Ovarian cancer (lifetime risk: up to 12%)
- Second colorectal cancer (within 10 years: 30%; within 15 years: 50%)
- Kidney/urinary tract cancer
- Brain cancer
- Biliary tract cancer
- Pancreatic cancer
- Small bowel cancer
The following risk factors place you at a higher risk of having HNPCC/Lynch Syndrome:
- A personal diagnosis of colorectal cancer before the age of 50
- A personal diagnosis of endometrial/uterine cancer before the age of 50
- Two or more Lynch Syndrome-related cancers (see the list above) diagnosed in you or a family member
- Two or more members of your family have been diagnosed with a Lynch Syndrome-related cancer (see list above)
- A family member with a known Lynch Syndrome mutation
How is HNPCC/Lynch Syndrome diagnosed? A very simple collection of cells from the inside of your mouth is all it takes. These cells are either obtained by a swab or by a mouthwash rinse that you swish and spit into a container. This container is then sent off to the lab for analysis.
If you carry this gene mutation, there is up to a 50% chance that one of your parents, your children, and/or a brother or sister will also have this mutation…so it is important to discuss genetic testing with them.
How is HNPCC/Lynch Syndrome managed? Most genetic counselors will recommend early cancer surveillance:
- Colorectal cancer: colonoscopies; every 1-2 years (starting between 20-25 years old, or 5-10 years earlier than the youngest colorectal cancer in the family, or at 40 years old; whichever comes first)
- Endometrial and Ovarian cancer: gynecologic exam, transvaginal ultrasound, endometrial tissue sampling, CA-125 blood test; every 1-2 years(starting at 25-35 years old)
- Screening for other Lynch Syndrome-related cancers (see list above) may be considered based on the presence of those cancers in a family member
- Surgical management:
- Removal of the colon (“colectomy”) is performed in those who develop colon cancer.
- Prophylactic colectomy can be performed for those who do not wish or are unable to undergo screening colonoscopies
- Prophylactic removal of the uterus and/or ovaries (“hysterectomy” and “oophorectomy”) will reduce the risk of developing endometrial and ovarian cancers, and may be considered for those who no longer wish to or able to bear children
What is this test going to cost me?
- The majority of patients who are at increased risk of having a HNPCC/Lynch Syndrome mutation are covered for testing and paying a copay of less than 10%. Most patients have no out-of-pocket costs for this test.
If you test positive for a HNPCC/Lynch Syndrome mutation can any health care insurance company determine your eligibility or charge you higher rates?
- No. The federal law “HIPAA” prohibits insurance companies from using the results of genetic testing in determining your eligibility for coverage and they can not charge you a higher rate.
**If after reading this post and you feel you may be a candidate for HNPCC/Lynch Syndrome genetic testing or you would simply like to learn more about it, please discuss this with your cancer care team.**
Unfortunately, only 2% of individuals who have HNPCC/Lynch Syndrome have been diagnosed!