Why does ovarian cancer occur?
What is a woman’s chance of getting ovarian cancer?
What are the risk factors for ovarian cancer?
What is meant by a family history of ovarian cancer?
How does your family history affect your chance of getting ovarian cancer?
Inheriting an ovarian cancer gene change
Cell growth is controlled by a cell’s genes. Genes contain the information that determines how our cells grow and work throughout our lifetime. This information can be passed from one generation to the next (inherited).
Sometimes, genes in ovarian cells develop a change. This can cause the cells to grow out of control, leading to cancer. These genetic changes, which occur throughout life are not inherited. They occur more often in older people. Why this happens is not fully understood.
The risk of getting these cancers increases with age.
There are many things that can influence a woman’s chance of getting ovarian cancer. These are called risk factors. The two most important things are being a woman and getting older. Most women who get ovarian cancer are over the age of 50. A family history of ovarian or breast cancer is also an important risk factor.
A family history of ovarian cancer means having one or more blood relatives who have ever had ovarian cancer. These relatives could be on either your father’s or mother’s side of the family. Some women will have a family history of cancer by chance alone.
However, a small number of women with a family history may have inherited a changed gene, which increases the risk of cancer. The women most likely to have inherited a changed gene are those with the strongest family history of ovarian cancer.
Understanding your family history of ovarian cancer can help to identify your chance of developing ovarian cancer:
A woman could have a high chance of getting ovarian cancer if she has:
Ovarian cancer caused by inheriting a changed gene is called hereditary cancer. We all inherit a set of genes from each of our parents. Sometimes there is a change in one copy of a gene which stops that gene working properly. This is also called a mutation.
There are several genes for which inherited changes may be involved in the development of both ovarian and breast cancer. These are genes which normally prevent a woman getting ovarian or breast cancer. Some of these are genes that you may have heard of, called BRCA1 and BRCA2. Their names come from the abbreviation of 'breast cancer one' and 'breast cancer two'. If a woman has inherited a change in one of these genes, she has a high chance of ovarian or breast cancer. It does not mean she is certain to get cancer.
Less than 5% of all ovarian and breast cancers can be explained by an inherited gene change in BRCA1 or BRCA2.
The earlier a cancer is found the more successful treatment is likely to be. We recommend that women concerned about their family history talk to their doctor. It may be appropriate for some women with a strong family history to be referred to a Family Cancer Centre. Here, their risk of getting ovarian or breast cancer, based on their family history, can be worked out and talked about in more detail.
Further information about ovarian cancer is available by ringing The Cancer Council Victoria’s Cancer Helpline on 13 11 20.
If you are worried about your risk of ovarian cancer based on your family history contact your doctor or nearest Family Cancer Centre.
