A pancreatic cancer patient learns of his Lynch syndrome diagnosis, which is genetic

About 10 percent of pancreatic cancer cases are thought to be hereditary – caused by an inherited genetic alteration that increases a person’s risk of developing the disease.

A genetic syndrome that could influence a person’s likelihood of developing pancreatic cancer, as well as other cancer types like colon cancer, is called Lynch syndrome. Lynch syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC), is caused by mutations in any of several genes that impact cells’ ability to repair damage to DNA.

Today is National Lynch Syndrome Awareness Day, providing an opportunity to discuss the frequency of this alteration, how it impacts pancreatic cancer risk and how it may inform treatment options for a patient.

How common is Lynch syndrome?

According to the American Society of Clinical Oncology, Lynch syndrome is one of the more common cancer-causing genetic syndromes, affecting about one in every 300 people.

If one of your parents has Lynch syndrome, you have a one in two chance of inheriting the mutation as well. While Lynch syndrome and other cancer-causing mutations, like BRCA mutations, increase a person’s lifetime risk of developing cancer, it does not mean that a cancer diagnosis is inevitable.

If you’re concerned about your risk of developing pancreatic cancer, take the Pancreatic Cancer Action Network’s (PanCAN) Risk Assessment Test.

How does Lynch syndrome affect pancreatic cancer risk?

Lynch syndrome is most closely linked to colon cancer risk, but it can also increase a person’s risk of developing endometrial, stomach, breast, ovarian, pancreatic and other cancer types.

About 5 percent of colon cancer cases are caused by Lynch syndrome. Lynch syndrome increases a person’s risk of developing pancreatic cancer by about nine-fold.

What can you do if you have Lynch syndrome?

If you have two or more first-degree relatives who have had pancreatic cancer, a first-degree relative who developed pancreatic cancer before the age of 50, or an inherited genetic syndrome associated with pancreatic cancer (like Lynch syndrome), you may have an increased risk of developing pancreatic cancer. PanCAN strongly recommends consulting with a genetic counselor to determine your risk and eligibility for a screening program.

If you have questions or would like additional information, contact PanCAN’s PanCAN Patient Services, who can provide resources for genetic counseling.

How can Lynch syndrome affect treatment options?

While mutations like Lynch syndrome are present in a patient’s germline, meaning every cell in the body is affected, alterations that occur within cancer cells can impact whether the tumor responds to a certain type of treatment.

Every pancreatic tumor is different. PanCAN strongly recommends molecular profiling of your tumor to help determine the best treatment options.

Patients who have Lynch syndrome have a higher likelihood of developing tumors with defective DNA mismatch repair or high microsatellite instability. These tumor alterations make a patient more likely to respond to an immunotherapy drug called Keytruda.

Keytruda was the first drug approved to treat any solid tumor, anywhere in the body, based on molecular alterations instead of the tumor’s location.

Knowledge about family history and genetic syndromes, like Lynch syndrome, can help someone understand and manage their own and their loved ones’ risk of developing pancreatic cancer. It can also provide insight into available treatment options.

Contact a PanCAN Patient Services Case Manager
For more information on genetic mutations, pancreatic cancer risk and molecular profiling, contact Patient Services.

Any treatments, including clinical trials, mentioned in this story may not be appropriate or available for all patients. Doctors take many things into account when prescribing treatments including the stage and type of cancer and the overall health of the patient. Contact PanCAN Patient Services for personalized treatment options.