If a person develops pancreatic cancer, it may have genetic mutations that affect how it responds to treatment. Genetic testing can provide valuable information to help doctors and individuals make treatment decisions.
Healthcare providers use genetic testing to learn more about the DNA in a person’s cells. Specific genetic mutations affect how cancer grows, including pancreatic cancer.
People who don’t have cancer may still consider genetic testing, depending on their family history. If someone inherits specific genetic mutations, it raises their risk of developing pancreatic cancer.
Take a moment to learn how doctors may use genetic testing to check for these genetic mutations.
Healthcare providers and genetic counselors use two main types of genetic testing to manage pancreatic cancer: germline testing and somatic testing.
Germline testing, or predictive genetic testing, can identify whether a person has inherited genetic mutations linked to pancreatic cancer. These include certain mutations on the following genes:
- BRCA1 and BRCA2
- MLH1, SH2, SH6, PMS2, and EPCAM
Many of these genetic mutations also raise the risk of other types of cancer, such as breast, ovarian, prostate, and colorectal cancer.
A healthcare provider or genetic counselor may recommend germline testing to someone who receives a pancreatic cancer diagnosis. This testing will identify whether the cancer has a genetic link, which may affect the treatment options.
A healthcare provider or genetic counselor may also recommend germline testing to someone who has a strong family history of certain types of cancer or a blood relative who tested positive for certain genetic mutations. If the blood relative has genetic traits linked to pancreatic cancer, those traits may run in the family.
When someone tests positive for genetic mutations linked to pancreatic cancer, their healthcare provider or genetic counselor may encourage their family members to get tested. Doctors call this cascade testing.
If someone receives a diagnosis of pancreatic cancer, their healthcare provider may order somatic, or tumor, testing on a sample of the tumor.
This will identify whether the cancer has mutations in specific genes that affect how it behaves and responds to treatment.
The results of somatic testing help the healthcare provider determine the most suitable and effective treatments. Certain targeted therapies are more effective in treating tumors with specific genetic mutations.
The results of a germline or somatic test may influence a person’s treatment plan for pancreatic cancer. That is because certain genetic mutations affect how pancreatic cancer responds to specific treatments.
For instance, research suggests that platinum-based chemotherapy might best suit people with pancreatic cancer who test positive for germline or somatic mutations in DNA repair genes. The BRCA1, BRCA2, and PALB2 genes are three examples of DNA repair genes.
According to a review in Cancer Management and Research, PARP inhibitors provide another promising treatment for pancreatic cancer in people with germline mutations in the BRCA1 or BRCA2 gene.
Scientists continue to study how people with somatic or germline mutations in these genes or other DNA repair genes respond to this treatment.
A person’s genetic test results can also help their doctor predict how pancreatic cancer will respond to other medications, such as larotrectinib (Vitrakvi), entrectinib (Rozlytrek), and pembrolizumab (Keytruda).
To conduct genetic testing, a healthcare provider collects a sample of blood or tissue from a person’s body. The type of sample depends on which kind of testing they order.
Before someone undergoes germline testing, their healthcare provider or genetic counselor will ask them about their personal and family medical history. This helps them determine whether germline testing is appropriate for them.
To conduct germline testing, a healthcare professional uses a needle and syringe to draw a sample of the person’s blood. They send this sample to a laboratory for genetic sequencing.
To conduct somatic testing, a healthcare professional collects a sample of pancreatic cancer from a person’s body. They may use endoscopic surgery to collect this sample.
To perform endoscopic surgery, the healthcare professional makes a small incision in the person’s abdomen. Then they insert an endoscope, which is a flexible tube, through the incision and use that tube to remove a sample of the tumor.
They then send the sample to a laboratory for genetic testing.
A person can talk to their healthcare provider or genetic counselor to find out about the cost of genetic counseling services and genetic tests.
If someone has health insurance and meets certain criteria, their insurance plan may cover some or all of the costs of germline testing, somatic testing, or genetic counseling.
They may contact their insurance provider to learn if their plan provides coverage, and how much they can expect to pay in co-payment, co-insurance, or deductible charges.
Under federal law in the United States, health insurance providers cannot use genetic tests to decide which people they cover or how much they charge for health insurance.
Federal law does not prevent life insurance, disability insurance, or long-term care insurance providers from using genetic test results to guide their coverage decisions. As a result, some people prefer to pay for genetic counseling and testing out of pocket to keep the results private.
Sometimes the results of genetic tests are inconclusive. In other words, the test may not provide enough information to know if a person has specific genetic mutations or not.
False-negative results are rare, but they do occur. This means that although the test shows a negative result, genetic mutations are present.
To help a person understand the results of their genetic test, their healthcare provider may refer them to a genetic counselor.
A genetic counselor can help the person understand what positive, negative, or inconclusive test results mean for them and their family.
A person should talk to their healthcare provider or a genetic counselor to determine whether they should get genetic testing for pancreatic cancer or other types of cancer.
Their healthcare provider or genetic counselor may recommend germline testing if the person:
- has a strong family history of pancreatic cancer or certain other types of cancer
- has a blood relative who has received a positive test for certain genetic mutations linked to pancreatic cancer
- has pancreatic cancer and their treatment team believes a genetic mutation may be the cause
Their healthcare provider or genetic counselor might recommend somatic testing if they received a diagnosis of pancreatic cancer.
If someone has a family history of pancreatic cancer or certain other types of cancer, their healthcare provider or genetic counselor may recommend germline testing.
If a person receives a diagnosis of pancreatic cancer, their treatment team may recommend germline testing, somatic testing, or both.
These types of genetic testing can identify the presence of specific genetic mutations that may affect how cancer develops.
Anyone concerned about their cancer risk should talk to their healthcare provider about whether genetic testing is appropriate for them.