One in two Australians will develop cancer by the age of 85. It is therefore not uncommon for several members of the same family to develop cancer, though in most cases the cancers will be unrelated.
However, for a small number of individuals, their family history suggests they may have inherited a genetic mutation in a cancer-related gene, which means their chance of developing cancer is much higher than the average population.
When cancer runs in the family
While most cases of cancer are not due to an inherited mutation, there is a possibility that cancer may run in your family or on one side of your family if:
- There are several family members who have cancers of the same type.
- There are several cases of rare cancers.
- Family members have developed cancer before the age of 50.
- Family members have developed more than one cancer ( for example cancer in both breasts).
- A relative has been found to carry the genetic mutation that increases their risk of cancer.
A small proportion of some cancers may demonstrate a familial tendency, including:
- retina (eye)
If your close relatives have had any of these cancers your local doctor can assess your family history and—if appropriate—refer you to a familial cancer clinic.
SA Clinical Genetics Services—Family Cancer Unit
Cancer Australia/ NBOCC (National Breast and Ovarian cancer Centre)
National Cancer Institute (USA)
Diethylstilbestrol (DES) and Cancer
DES was taken by some women from the 1950s to the 1970s to try and prevent miscarriage and other pregnancy complications. Although the majority of persons exposed to DES during pregnancy or in utero will not experience any negative health effects, available research findings indicate that exposure to DES increases the risk of some health problems including some cancers.
This webpage was last reviewed and updated in January 2020.