This information explains how having a mutation in the STK11 gene may affect you and your family.
In this resource, the word “family” means people related to you by blood. They’re not related to you through marriage or adoption. We also call these family members your blood relatives.
Your STK11 gene normally helps prevent tumors from developing. A mutation in this gene causes it to stop working like it should.
It is important to understand that having a mutation in this gene does not mean you will definitely develop cancer. It means that you have an increased risk of developing certain types of cancers. The type of cancer can vary among people who have mutations in this gene, even within the same family.
What is my cancer risk if I have an STK11 mutation?
If you have a mutation in the STK11 gene, this means you have a condition called Peutz-Jeghers syndrome (PJS).
STK11 mutations increase your risk for hamartomatous (non cancerous growth) colon polyps and certain types of cancers, including:
- Breast cancer
- Colon cancer
- Stomach cancer
- Cancer of the small intestine
- Pancreatic cancer
STK11 mutations may also increase your risk for other less common cancers. Examples of less common cancers linked to STK11 are:
- Testicular cancer (sertoli cell)
- Ovarian tumors (ovarian sex cord tumors with annular tubules (SCTAT)) or mucinous tumors of the ovary
- Cervical cancer
- Uterine cancer
- Lung cancer
The risks of developing these less common cancers are not well established.
As we learn more about these mutations, we may learn they increase the risk for other types of cancers. Your genetic counselor will give you more information about your cancer risk if you have a mutation.
What can I do about my cancer risk if I have an STK11 mutation?
Your genetic counselor will review your results. They will talk with you about what cancer your mutation is linked to. As we research these mutations, we may learn they raise the risk for other types of cancers.
Your genetic counselor will also review your personal and family history of cancer and give you cancer screening recommendations. They may recommend you start having cancer screenings at a younger age or have them more often than most people. They may also suggest you get specialized screenings to help find cancer as early as possible.
Some examples of these cancer screenings include:
- Earlier breast screening including magnetic resonance imaging (MRI) scans or an option to consider risk-reducing breast surgery (mastectomy).
- Colonoscopy, upper endoscopy, and other GI imaging starting at an early age.
- Gynecological exam with consideration for imaging.
- Physical exam for testicular masses.
Some of these screenings will happen once a year. Others may happen more or less often. Your genetic counselor will talk with you about screening recommendations and how often you should get them. They will also talk with you about whether there are any other screening or prevention options that may be right for you.
What does an STK11 mutation mean for my blood relatives?
If you have a mutation, your biological parents, siblings, and children each have a 50% chance of having the same mutation. Your distant family members may also be at risk for having the same mutation.
Males and females have an equal chance of passing down a mutation in their family. You only need to inherit a mutation from one parent to have an increased risk for cancer.
Your genetic counselor will review your family history and talk with you about whether they recommend genetic testing for your blood relatives.
What does this mean for family planning?
If you have an STK11 mutation and plan to have children, there are options to prevent your children from inheriting the mutation. You may want to consider discussing these options with your reproductive partner and a genetic counselor.
What happens if I do not have a mutation?
If you do not have a mutation or if we find a variant of uncertain significance (VUS), your genetic counselor will review your personal and family history of cancer. They’ll talk with you about the general cancer screening guidelines you should follow.
A VUS is a change in a gene, but we don’t yet know if it is linked with a higher risk for cancer. Most VUS are eventually found to be normal changes that do not affect your health.