What cancer risks are there if you have a PALB2 gene alteration?
Based on current evidence, we estimate that someone who has a PALB2 gene alteration has the following risks of cancer:
Breast, Ovarian and Pancreas:
|Breast cancer||Ovarian cancer||Pancreas cancer||Male breast cancer|
|By age 50||13-21%||less than 1%||less than 1%||less than 1%|
|By age 80||44-63%||around 5%||around 2-3%||around 1%|
For comparison, around 12% women in the general population develop breast cancer over their lifetime, and up to 2% develop ovarian cancer. 2% develop ovarian cancer.
Prostate: There is no evidence of an increased prostate risk, but studies have been small so far.
Colon: There is no evidence of an increased colon cancer risk, but studies have been small so far.
Other cancers: There is no evidence of increased risk for other cancers, but some types will not have been studied.
What cancer screening is available for individuals with a PALB2 alteration?
We recommend increased surveillance using a combination of breast MRI and mammograms from the age of 30 years for women. The aim is to detect breast cancers at an earlier stage, when the cancer is easier to treat. However, surveillance is not perfect and may miss cancers. In addition, sometimes changes are seen on the scans that later turn out not to be cancer, but do cause worry and can lead to unnecessary extra tests. We are not currently recommending surveillance for other cancers. This is because the risks are lower than for female breast cancer, and current ways of screening for the other cancers are not yet proven to detect cancer earlier.
What preventative surgery options are available for individuals with a PALB2 alterations?
We know that your risk of cancer will vary according to your family history. I If you have a strong family history of breast cancer you may wish to consider preventative surgery of the breasts (also called risk reducing mastectomy). If you have a close relative affected with ovarian cancer then preventative removal of the ovaries may also be an option to consider. Please talk to your Genetic Counsellor or Clinical Geneticist if you would like to look into this further.
PALB2 and Fanconi Anemia
PALB2 is a rare cause of Fanconi Anemia (click here for more information on Fanconi Anemia). Individuals with one normal copy of the PALB2 gene and one mutated gene are called “carriers”. If two carriers of PALB2 mutations have children then there is a 1 in 4 chance that their child could be affected with Fanconi Anemia. In reality this is a very rare situation as carriers are rare in the general population. We estimate that around 1 in 770 people in the general population are PALB2 mutation carriers so the chances of a PALB2 carrier having a child affected with Fanconi Anemia would be less than 1 in 3000. There are some exceptions to this, for example if a PALB2 carrier has children with a related family member such as a cousin. If you have concerns we recommend you discuss this with a Genetic Counsellor or Medical Geneticist. See also: Implications for other family members