We are all born with the same genes. People can be born with changes in these genes, or they can develop changes to their genes over time. This can contribute to cancer risk.
Experts at Memorial Sloan Kettering’s Clinical Genetics Service can help you and your family understand if changes in cancer-related genes might have played a role in your child’s diagnosis, and if there are other family members who might be at risk. Today, we know more about the genes that contribute to childhood cancer than ever before. Our genetic counselors will sit down with you to discuss your child’s medical history, as well as any cancers and related medical conditions in your family.
Genetic testing is an important part of pediatric cancer care because it can give us details about how a cancer can best be treated. It may also provide information that tells us if the cancer has a hereditary factor.
We offer genetic testing to almost every young patient we treat. Of course, it’s entirely up to you and your family if you’d like to pursue it. Our geneticists and genetic counselors can talk with you about this and other medical decisions, so you can make the choices that are right for you and your loved ones.
When a hereditary cancer syndrome is identified, we can help coordinate the necessary care as part of our screening program. The aim of the MSK Kids Cancer Predisposition Screening Program is to identify people at risk for cancer and provide them surveillance and risk-reduction options. In 2017, we played a leading role in an international initiative put forth by the American Association of Cancer Research formalizing screening recommendations for children at risk.
Multiple Cancer Predispositions
- Li Fraumeni syndrome
- Constitutional mismatch repair deficiency
Hematologic Malignancy Predispositions
Bone Marrow Failure Syndromes
- Fanconi anemia
- Dyskeratosis congenita
- Diamond Blackfan anemia
- Shwachman Diamond syndrome
- Severe combined immunodeficiency (SCID)
- Hemophagocytic lymphohistiocytosis (HLH)
- Neurofibromatosis type 1
- Neurofibromatosis type 2
Solid Tumor Predispositions
- WT1-related disorders
- Beckwith Wiedemann syndrome
- Hereditary neuroblastoma
- Hereditary retinoblastoma
- DICER1-related disorder
- Nevoid basal cell carcinoma syndrome (aka Gorlin syndrome)
- PTEN hamartoma tumor syndrome
- Rhabdoid tumor predisposition syndrome
- Von Hippel Lindau syndrome (VHL)
- Familial adenomatous polyposis (FAP)
- Noonan syndrome
Metabolic Cancer Predisposition Syndromes
- Hereditary pheochromocytoma and paraganglioma
- Hereditary Leiomyomatosis and Renal Cell Cancer (HLRCC)
- Multiple endocrine neoplasia type 1 (MEN1)
- Multiple endocrine neoplasia type 2 (MEN2)
We’ve gathered answers to some frequently asked questions about genetic testing for pediatric cancer predisposition. If you would like to meet with one of our genetic counselors to learn more, give us a call at 833-MSK-KIDS.
What are genetic mutations?
What is a hereditary cancer?
How do you find mutations in genes that cause hereditary cancer syndromes?
What are the benefits of genetic testing? Are there any risks?
Will the information about my genetic testing be kept private and confidential?
What potential test results could come back, and what do they mean?
If a person has a genetic mutation, what are the risks to other family members?
If I have a mutation, what are my family planning options?
Will insurance cover genetic counseling and testing?
Where can I learn more?
- What are genetic mutations?
- What is a hereditary cancer?
- How do you find mutations in genes that cause hereditary cancer syndromes?
- What are the benefits of genetic testing? Are there any risks?
- Will the information about my genetic testing be kept private and confidential?
- What potential test results could come back, and what do they mean?
- If a person has a genetic mutation, what are the risks to other family members?
- If I have a mutation, what are my family planning options?
- Will insurance cover genetic counseling and testing?
- Where can I learn more?
Genes are made of DNA, and DNA contains carefully spelled-out instructions that help our bodies develop and function. Each person has about 20,000 genes in every cell in his or her body. A change in DNA sequencing, or the ordering of the different parts that make up the DNA in a gene, can cause a gene to work abnormally or stop working all together. Changes that make the gene work improperly are called mutations.Back to top
All cancers involve genetic mutations. Most of these mutations happen only in the cancer cells and are not present in the rest of the cells in the body. However, sometimes a cancer-related gene mutation is present in all or most of a person’s cells, not just in the cancer cells. This can contribute to cancer risk. If a mutation is present in all cells in the body, then it is considered a hereditary gene mutation because it can be passed down to the next generation.
When children inherit a mutation in a cancer gene, they have a higher chance of developing certain cancers. This is called a hereditary cancer syndrome. At least 10 percent of all cancers in children are associated with a hereditary mutation. Sometimes a child is born with a mutation in a cancer gene, but the mutation is not inherited from a parent. Instead, the mutation developed by chance in that gene and can be passed down to the next generation.Back to top
We can test genes for mutations that cause hereditary cancer syndromes using blood, saliva, or skin samples. We usually start testing in a member of the family who currently has or has had cancer. If we find a mutation, we can test other family members for the same one.
Mutations in different cancer genes can cause the same type of cancer. These related cancer genes can be tested one at a time, or they can be tested all at the same time. Testing multiple genes at once is called “multigene panel testing.” Testing several related genes all at once can be a quick way to find the cause of cancer in a family. A genetic counselor can talk specifically about the genes that are included on a given panel test.Back to top
There are many benefits of genetic testing. Testing can provide a better understanding of why a child’s cancer developed. It can shed light on cancer risk for an individual and members of that person’s family. Genetic test results can also help doctors design a personal cancer screening program, and can help people decide about options for reducing their cancer risk. Genetic testing can help families make reproductive decisions about having additional children.
There are no risks of physical harm from testing other than that of a blood draw. However, genetic testing can have emotional effects. If a mutation is found, it can impact other family members. Some relatives may not want to know the results. There is also a theoretical chance that someone could use your genetic test results against you. This is considered discrimination, and there are federal and state laws that forbid using genetic test results as an influencing factor in health insurance costs or employment decisions – but this is, of course, not a guarantee, and some families choose to not go through with genetic testing for that reason. However, most insurers cover the cost of genetic testing with no penalty – for example, no increased premiums and no risk of being dropped by the insurance carrier.
Genetic testing is a personal choice; however, doctors, genetic counselors, and other members of our team are here to help with the decision-making process. Reach out with any questions at 833-MSK-KIDS.Back to top
Absolutely. Genetic test results and medical records are kept completely private and confidential.Back to top
Genetic testing can produce three results: positive, negative, and variant of unknown significance. Here’s what they mean:
Positive: We’ve identified a gene mutation, which means there is an increased risk for certain types of cancer. Cancer risks vary according to the affected gene, and sometimes the type of mutation identified in that gene. Often, having the mutation does not mean a person will develop cancer, just that there is an increased risk.
Once we discover a gene mutation, we may offer that person tailored or more frequent screening exams to try to find cancers that may develop as early as possible. We may also offer certain types of surgeries that could help reduce the risk of developing cancer.
If a person has a genetic mutation, other family members may also carry the same mutation. Genetic counselors can help identify who in the family is at risk and discuss when testing would be appropriate for those relatives. Before having genetic testing, people should ask their relatives whether they would like to know this information, as the results may directly impact them.
Negative: This means we didn’t find a mutation that increases cancer risk.
Variant of Uncertain Significance: This means we identified a change in a gene, but it’s not yet known whether it could cause an increased risk of cancer. The scientific community is still learning which changes in genes are harmless and which aren’t. In this case, we will look at a person’s individual and family health history to make cancer screening recommendations.Back to top
This depends on the type of mutation found. Many mutations that cause an increased risk of cancer are dominant mutations. We all have two copies of each gene: one copy from our mother and one copy from our father. With dominant mutations, having a change in just one copy of the cancer gene carries an increased risk of cancer. Having a dominant cancer gene mutation means having a 50% chance to pass it to each child.
Other hereditary cancers are caused by recessive mutations. This means that both copies of a cancer gene have mutations, which causes the increased cancer risk. A child with two mutations usually inherits one from each parent. Each parent then is a mutation carrier, and often carriers do not have increased cancer risks. With recessive conditions, there is a 25% chance that each child will have the increased cancer risk. The chance for their children to have the recessive condition depends on the carrier status of that person’s partner.
Many gene mutations that cause cancer in adults do not increase the risks for cancer in children. A genetic counselor can help determine if there is a risk to younger family members and suggest an appropriate age for them to have their own genetic testing.Back to top
There are many family planning options that our genetic counselors can discuss with you. It is important to know that reproductive decision making is very personal, with no right or wrong choice. The vast majority of cancer predisposition mutations have no effect on a person’s ability to conceive a child; it’s just that the child has a risk of also having the cancer predisposition. Some families who want to avoid having a child with the same cancer predisposition will take steps to avoid that. Other families choose not to do anything differently when they have children.
One reproductive option involves testing embryos for a known mutation before they are implanted in a woman’s uterus during in vitro fertilization. This is called preimplantation genetic diagnosis (PGD). PGD may be an option for families who want to make sure their children do not have the known hereditary cancer risk in their family. To learn more, ask for a referral to a specialist before attempting pregnancy. Prenatal testing for a known mutation may be possible through procedures called chorionic villus sampling (CVS) or amniocentesis. Having children through adoption or with the assistance of donor eggs or donor sperm are two other possible family planning options.Back to top
Many insurance companies and managed care plans pay for genetic counseling and testing. Before you have genetic testing, check with your insurance provider to see what they’ll cover.Back to top
Your family can come to the MSK Kids Pediatric Cancer Predisposition Screening Program. The goal of the program is to identify people at risk for cancer and provide surveillance and risk-reduction options. Call us at 833-MSK-KIDS to learn more and receive answers to any other questions you may have.Back to top