Li-Fraumeni syndrome genetic and predictive testing

Cancer is a common condition. It will affect half (50%) of the population at some point. As we get older we are more likely to develop cancer as our bodies become less effective at protecting us.

Most cases (about 9 out of 10) happen by chance, but a few (about 1 out of 10) happen when someone has inherited an increased risk from a member of their family.

In some families, there are more cases of cancer than normally happen by chance. In some of these families, cancer can be due to an inherited risk from our parents.

People with Li-Fraumeni syndrome have a 9 in 10 (90%) increased risk of developing specific types of cancer by the age of 60. Li-Fraumeni syndrome can cause cancers such as:

  • breast
  • osteosarcoma
  • soft tissue sarcomas
  • brain tumours
  • adrenocortical carcinomas
  • childhood cancers


Genes are coded messages that give instructions for how cells in the body grow and function. Genes come in pairs and we inherit one copy from each parent.

The function of the TP53 gene is to protect us from cancer by controlling the growth of cells. 

If someone inherits a mutation (fault) in one copy of the TP53 gene, they will be more likely to develop cancer. People with a change in the TP53 gene have Li-Fraumeni syndrome.

Someone with a TP53 gene mutation also has one normal copy. Only one copy of each gene pair is passed on to a child. If someone has a mutation in one copy of the gene, they have a 1 in 2 (50%) chance of passing on this mutation to each child they have, regardless of their biological sex or the child’s sex. 


We can carry out tests to investigate whether Li-Fraumeni syndrome runs in your family.

You can read more about further genetic testing and predictive testing for Li-Fraumeni syndrome.

In some families no genetic testing is possible. 

Deciding whether to be tested

Deciding to have genetic testing is a personal decision and can be a difficult and complex process.

Not everyone will choose to have genetic testing. If you decide against it you may still be eligible to have regular screening and we will discuss this with you. 

You may wish to consider these points before deciding. There are no right or wrong answers to these questions, but it is worth thinking about what your answers might be, so that when you have your result you have an idea of how you may wish to proceed.


  • Why now?
  • Will it change your immediate treatment?
  • What other challenging events are happening in your life?

Psychological impact of knowing

  • How will you feel if a Li-Fraumeni syndrome related gene mutation is identified?
  • How will you share this information within the family?
  • How this test result could affect you and your future?
  • Who you plan to talk to about this test and result?
  • How this test could impact on your family, children and relationships?

Assessing your own coping strategies

  • How have you dealt with difficult situations in the past?
  • What strategies do you use to help you deal with difficult news?
  • Could this have an impact on your employment or insurance?
  • How you will adjust to your result?

Next steps

  • What might you do about your risks from Li-Fraumeni syndrome if we find that you have a gene mutation?
  • Who you would like us to share your result with?

Research studies

Regardless of the result of your testing, there may be an opportunity for you to take part in research. Your genetics clinician or a research nurse will discuss this with you. For further information, contact a member of the research team on 020 7188 2603.

Resource number 5349/VER1
Published date March 2023
Review date March 2026

Contact us

If you have any questions or concerns, please contact your genetics clinician.

Phone: 020 7188 1364 Monday to Friday, 9am to 5pm.

Cancer Genetics Service, Guy’s Regional Genetics Service
Guy’s Hospital
Great Maze Pond
London SE1 9RT

Do you have any comments or concerns about your care?

Contact our Patient Advice and Liaison Service (PALS)

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