What Is the PTEN Gene?
PTEN is a gene that helps stop cells from replicating and growing out of control. It is one of many genes that serve as “brakes,” keeping errant cells from forming tumors. If you have changes, or a mutation, in your PTEN gene, noncancerous tumors, called hamartomas, can form in your body. A PTEN mutation may also increase your risk for developing cancerous tumors.
You can inherit a PTEN mutation from one of your parents or acquire one later on in life.
If You Carry a PTEN Mutation, What Cancers Are You at Risk For?
An inherited PTEN mutation can trigger several health disorders, which are often grouped together and referred to as PTEN hamartoma tumor syndrome (PHTS). Conditions that fall under the umbrella term PHTS include:
- Cowden Syndrome This disorder causes hamartomas and increases your chances of developing a number of cancers, including breast cancer, thyroid cancer, uterine cancer, and colon cancer. People with Cowden syndrome might have larger-than-normal heads (macrocephaly) and experience developmental delays, such as autism.
- Bannayan-Riley-Ruvalcaba Syndrome This can cause hamartomas, macrocephaly, learning disabilities, and autism. Other signs and symptoms of this syndrome include weak muscle tone, scoliosis, seizures, and thyroid problems.
- Proteus or Proteus-Like Syndrome In addition to causing hamartomas and macrocephaly, this condition can lead to an overgrowth of bones, skin, and other tissues.
Acquired, or “somatic,” PTEN mutations are common in many types of cancers, including: (1)
- Prostate cancer
- Uterine cancer
- Brain tumors
Because PTEN mutations are among the most common seen in human cancers, they can play a role in many other cancers as well.
How Does PTEN Increase Your Risk for Cancer?
PTEN is a tumor suppressor. When it works as it should, PTEN stops cells in your body from growing and dividing too quickly or in an uncontrolled way. But when a mutation occurs, the gene can’t regulate how the cells grow, and cancer can form. (1,2)
Can You Be Tested for PTEN?
Yes, a PTEN mutation can be detected on a genetic blood test.
This isn’t a routine test, and it’s usually only given to certain children or adults who have a family history, specific symptoms, or are otherwise thought to be at high risk of having the mutation. (1)
Why Is It Important to Know if You Are at Risk for PTEN?
Children and adults with a family history of a PTEN mutation are at risk of having it themselves. The mutation is inherited in an autosomal dominant manner. That means if your parent has a mutation, you have a 50 percent chance of having it, too. (2)
Your doctor might recommend genetic testing if you or your child have one or more of the following: (1)
- A family history of a PTEN mutation
- Several hamartomas, especially in the gut area
- Developmental delays
- Dark freckles on the penis
- Breast cancer
- Thyroid cancer
- Uterine cancer
History of the PTEN Gene: When Was It Discovered?
Since PTEN was discovered, researchers have learned it’s one of the most frequently mutated tumor suppressors found in cancer. (5)
What Do You Do if You Test Positive for PTEN?
Having a PTEN mutation doesn’t mean you have cancer, but it does mean you’re at a greater risk. Identifying a PTEN mutation can help you and your doctor plan treatment and prevention strategies.
You’ll probably need more frequent cancer screenings than someone without the mutation.
If you have a PTEN mutation, your healthcare provider might recommend the following: (1)
- Colonoscopies starting at age 35–40
- Monthly breast self-exams
- Mammograms starting at age 30
- Yearly uterine screenings
- Yearly thyroid screenings
- Yearly kidney screenings
- Yearly skin exams