Genetics and family history can often play a significant role in a person’s health, and those who have a strong history of certain cancers within their family can benefit from speaking to their doctor and inquiring about Lynch syndrome.
Here’s what you need to know about Lynch syndrome:
What Is Lynch Syndrome?
Lynch syndrome, also known as hereditary non-polyposis colorectal cancer (HNPCC), is a condition that makes people more susceptible to certain cancers, and is the most common cause of hereditary colorectal (colon) cancer.
Lynch syndrome has a 50 percent chance of being passed down from parents to children. Carriers are predisposed to certain cancers at younger ages than others (often in their 30s and 40s), and have a 40 percent to 80 percent chance of developing colorectal cancer by age 70. It also increases their risk for cancers of the uterus, ovaries, and stomach.
Causes of Lynch Syndrome
Lynch syndrome is caused by a problem in one of five genes (MLH1, MSH2, MSH6, PMS2 and EPCAM), which affects DNA mismatch repair—your system’s process of identifying and fixing cellular mutations and deficiencies.
These genes normally protect against developing certain cancers, but when you have Lynch syndrome, your cells don't fix the errors and divide, creating more flawed cells that can develop into cancer over time.
People with Lynch syndrome are predisposed to get certain cancers before age 50, including:
Colon and rectal cancer patients may not experience symptoms in the early stages of the diseases, yet the following—similar to those of other colon diseases—may manifest in advanced stages:
Consult your physician for proper diagnosis if you experience any of these.
As many as 1 in 300 people are estimated to be carriers of the gene alteration associated with Lynch syndrome, making it one of the most common hereditary cancer syndromes. It is also responsible for causing about 4,000 colorectal cancers and 1,800 uterine (endometrial) cancers per year in the United States, according to the Centers for Disease Control and Prevention.
Lynch syndrome can also exhibit in other forms, such as Muir-Torre syndrome and Turcot syndrome, both of which raise your risk of other cancers.
Turcot syndrome is a condition in which people develop brain tumors and colorectal cancers.
Muir-Torre syndrome is a form of Lynch syndrome in which people develop uncommon skin lesions or tumors, including sebaceous adenomas, sebaceous epitheliomas, sebaceous carcinomas, and Keratoacanthoma.
How to Diagnose Lynch Syndrome
If you’re concerned you may have Lynch syndrome in your family, the first step is to talk to a doctor or genetic counselor, who can test or research for patterns of inherited cancers.
Typically a doctor will inquire about your family health history, checking for diagnoses of colorectal and/or endometrial cancer in multiple relatives on the same side of a family, or family members who were diagnosed with an early onset of cancer before age 50.
It can be confirmed through a blood test, which can determine if someone carries a mutation that can be passed down in one of the genes associated with Lynch syndrome.
While there is no cure for Lynch syndrome, those who are diagnosed should undergo lifelong cancer screening, beginning in adulthood.
Your screening schedule will depend on your family history and whether you’ve had DNA testing.
Here are some general guidelines:
- Colonoscopies every one to two years, beginning at age 20 to 25.
- Endoscopies every three to five years, starting in your early to mid-30s.
- Pelvic exams, uterine biopsies, or transvaginal ultrasounds to check your uterus and ovaries, once a year, starting around age 30.
Men with Lynch syndrome have a 60 percent to 80 percent risk of developing colon cancer in their lifetimes, and undergoing a colonoscopy every one to two years decreases the mortality rate of colon cancers.
Some people with Lynch syndrome choose to have their colon taken out to help prevent cancer later on. Women who don’t want children in the future may also have their uterus and ovaries removed.
The objective in treating Lynch syndrome is removing the polyps and any presence of cancer that develops as a result. This can be done either through an endoscopic approach or surgery. If your doctor finds polyps during an examination, they may be able to remove them during the colonoscopy, but if they find evidence of cancer, they may recommend surgery.