Genetics & Cancer Risk
Navigating a CHEK2 mutation with Sharsheret
Learnwhat a CHEK2 mutation means for your health, how it can guide informed decisions, and where to find trusted support as you plan next steps.
Navigating a CHEK2 mutation with confidence.
While BRCA is a more familiar mutation and leads to a greater chance of someone developing breast cancer or ovarian cancer, CHEK2 is another mutation running through Jewish families that both men and women should pay attention to.
Learning about a CHEK2 mutation can be an opportunity to take an active role in your health. With clear, reliable information and thoughtful guidance, you can get questions answered, understand your options, and make a plan that reflects your values and needs. Sharsheret is here to support you with expertise, compassion, and trusted resources as you move forward with confidence.
CHEK2 FAQs
Cancer Risk
Risk Management
Treatment
CHEK2 mutation frequently asked questions
When you contact Sharsheret, you’ll connect with a caring professional who will listen, learn about your needs, and guide you to the right support — completely free and confidential.
CHEK2 is a gene that helps repair damage to your DNA. People who are born with changes — called mutations — in their CHEK gene have an increased risk for certain types of cancer.
People with an inherited mutation in CHEK2 have an increased risk for certain cancers, including:
- Breast cancer in women
- Male breast cancer
CHEK2 mutations have also been linked to an increased risk for prostate and other cancers, but more research is needed to confirm this.
Although the lifetime risk for cancer with a CHEK2 mutation is higher than average, not everyone with the mutation develops cancer. Following the guidelines for screening and prevention increases the chances of preventing cancer or catching it at its earliest and most treatable stage.
People with a CHEK2 mutation may have options for screening, prevention and treatment for hereditary cancer. There are expert guidelines and clinical trials that focus on:
- Screening and early detection
- Risk-reduction
- Treatment
These guidelines are based on the most current research and are updated yearly. People who test positive for a CHEK2 mutation should speak with a genetics counselor to make sure their medical care is based on the most up-to-date information.
If you test positive for a CHEK2 mutation, you should inform your close blood relatives (first-, second-, and third-degree relatives) about your test results and encourage them to speak with a genetics counselor.
CHEK2 mutations are passed down from parents to children. Each person with a CHEK2 mutation has a 50% chance of passing their mutation on to each of their children. Children who did not inherit their parent’s CHEK2 mutation cannot pass the mutation to their children.
People with a CHEK2 mutation who never develop cancer can still pass their mutation on to their children. A child who inherits a parent’s CHEK2 mutation will be at increased risk for cancer.
Cancer risk with CHEK2 gene mutation
Cancer risks may vary based on your specific mutation and family history. If you have tested positive for an inherited CHEK2 mutation, we recommend that you speak with a Sharsheret genetics counselor who can look at your personal and family history of cancer and can help you choose the best plan for managing your cancer risk.
Other cancer risks for people with a CHEK2 mutation
In the past, the NCCN guidelines listed colorectal cancer as increased for people with a CHEK2 mutation. NCCN has updated their guidelines to indicate no increased risk for colorectal cancer with a CHEK2 mutation. Some research has linked CHEK2 mutations to other cancer risks, such as thyroid cancer. More research is needed to prove these links.
It is important to note that cancer risks are estimates over the course of a person’s lifetime. Your lifetime risk and risk over the next five years will vary depending on:
- Diet, exercise, lifestyle and other factors
- Current age
- Gender
- Specific mutation
- Personal and family health history
Risk management for individuals with inherited CHEK2 mutations
Experts at the National Comprehensive Cancer Network (NCCN) created guidelines for people with a CHEK2 mutation to manage their cancer risk. NCCN notes that some mutations (for example a mutation known as IIe157Thr) may be associated with lower breast cancer risks than other mutations. We recommend that you speak with a genetics counselor who can look at your personal and family history of cancer and can help you decide on a plan to manage your risk.
| Beginning Age | Recommendation | Additional Information |
| 25 | Learn to be aware of changes in your breasts. | |
25 (or earlier based on youngest age of breast cancer in the family) | Breast exam by doctor (also known as a clinical breast exam) every 6-12 months. | The guidelines recommend that people who have risk-reducing mastectomy continue to receive clinical breast exams. |
| 30-35 | Yearly Mammogram | |
| No Set Age | More research is needed to show whether people with inherited CHEK2 mutations benefit from risk-reducing mastectomy. Discuss with your doctor about the option of risk-reducing mastectomy based on your personal and family history of cancer. | Risk-reducing mastectomy lowers breast cancer risk by 90%, but has not been shown to improve survival. Even after double mastectomy, some breast tissue, and therefore cancer risk remains. Clinical breast exam should be continued after risk-reducing mastectomy. |
| No Set Age | Discuss the benefits, risks and costs of medications to lower the risk for breast cancer with your doctor. | Tamoxifen or other estrogen-blocking drugs may lower breast cancer risk. Medications or vaccines are being studied in clinical trials. |
| 75 | Have a discussion with your doctor about whether to continue, stop or change breast screening. |
Currently there are no guidelines on male breast cancer screening for people with a CHEK2 mutation. Speak with your doctor about the benefits and risks of screening.
Research suggests that CHEK2 mutations may also increase the risk for prostate cancer. More research is needed to better define the exact risk for people with a CHEK2 mutation.
| Beginning Age | Recommendation |
| 40 | Have a conversation with your doctor about the potential benefits, risks, costs and limitations of screening for prostate cancer. If you choose to have screening, the guidelines recommend a Prostate Specific Antigen (PSA) test. Many experts also recommend a digital rectal examination that allows your doctor to feel for abnormalities in the prostate. |
There isn’t enough research to show that people with a CHEK2 mutation benefit from extra screening or prevention for other types of cancer. Because of this, experts recommend following general population screening guidelines and considering your family history when managing these risks. National guidelines exist for screening the following cancers:
- Lung
- Cervical
- Colorectal
Cancer treatment for people with inherited CHEK2 mutations.
People with an inherited CHEK2 mutation who have been diagnosed with cancer may have different treatment options than people without a mutation.
If you have an inherited CHEK2 mutation, have been diagnosed with cancer and any of the situations below apply to you, you may wish to speak to your doctor about your medical options. You may also consider enrolling in a clinical trial studying which treatments work best for people with an inherited CHEK2 mutation.
Regardless of cancer type, people with a CHEK2 mutation may benefit from biomarker testing and may qualify for clinical trials looking for more effective treatments for cancer.
You are making breast cancer surgical decisions
Experts estimate that women with CHEK2 mutations who have been diagnosed with cancer have about a 6-8% risk for developing a second cancer within 10 years. Because of this increased risk, some women who are diagnosed with breast cancer who test positive for an inherited mutation in CHEK2 may choose bilateral mastectomy rather than lumpectomy and radiation. Mutation carriers who undergo mastectomy are less likely to develop a second breast cancer.
Targeted therapies for advanced cancers
PARP inhibitors are a type of targeted therapy that work by blocking a protein used to repair DNA that has been damaged. They were initially developed to treat cancers in people with an inherited BRCA1 or BRCA2 mutation. Since then, research and additional FDA approvals have expanded use of PARP inhibitors to more situations. People with a CHEK2 mutation who have been diagnosed with cancer may want to ask their doctor about PARP inhibitor therapy.
You have metastatic prostate cancer
The PARP inhibitors, Lynparza (olaparib) and Talzenna (talazoparib) have received FDA approval to treat metastatic castration-resistant prostate cancer (mCRPC) with a mutation in CHEK2 or another gene linked to a certain type of DNA damage repair.
PARP inhibitors for other advanced cancers with no treatment options
If you have a CHEK2 mutation and advanced cancer that no longer responds to standard therapy, you may want to talk with your doctor about whether you might benefit from treatment with a PARP inhibitor.