Who is at risk?
ALL WOMEN have some risk of ovarian cancer.
What factors contribute to your risk for ovarian cancer*?
Not every factor has the same impact on risk. Some increase your risk only slightly. Others can raise it much more. These risk factors include:
Age – your risk increases as you get older, ovarian cancer is more common in women aged 50-79.
Family History – your risk is higher if you have any close blood relatives who have had breast cancer prior to age 50 or ovarian cancer at any age.
Reproductive History – your risk is higher if you have not delivered a child or have a history of difficulty getting pregnant.
Oral contraceptives/hormone replacement – Your risk is lower if you have used oral contraceptives. Your risk may be higher if you have taken hormone replacement.
Ethnicity – Jewish women of Eastern European (Ashkenazi) background have a higher risk. French Canadians of certain ancestry may be at increased risk.
Other factors – Your risk may be higher if you have a history of a condition called endometriosis.
*These factors are primarily known to increase the risk for the most common type of ovarian cancer, epithelial ovarian cancer; the risk factors for other ovarian cancers are not as well known.
Use of talcum powder
Research studies exploring use of asbestos-free talcum powder on the female genital area and the risk of ovarian cancer have been largely inconclusive. Some studies suggest a slight risk, while others do not.
BRCA1 and BRCA2 (Breast Cancer 1 and 2)
The BRCA 1 and BRCA 2 genes are involved in most cases of hereditary ovarian cancer. Everyone has BRCA 1 and BRCA 2 genes that are known as tumour suppressors. Mutation of these genes has been linked to hereditary breast and ovarian cancer.
Women who test positive for the BRCA 1 and BRCA 2 gene mutation are at increased risk for both ovarian and breast cancer. Often with the BRCA1 and BRCA2 mutation, breast cancer appears at younger ages and increases the risk of a second cancer.
Populations at increased risk for having the BRCA1 and BRCA2 mutations are:
Women of Ashkenazi Jewish descent (risk is 1 in 40)
French Canadians of certain ancestry may be at increased risk
Icelandic and Dutch populations
Watch: Know Your Genes is an initiative to build awareness of the role of BRCA gene mutations in ovarian cancer.
Other gene mutations
Some incidents of ovarian cancer are related to other gene mutations, such as the Lynch Syndrome, also known as hereditary nonpolyposis colorectal cancer (HNPCC).
Populations at risk for having this mutation have:
Three or more relatives with an Lynch syndrome-related cancer (colorectal, endometrial, small bower, ureter or renal pelvic, ovarian); and one relative must be a first-degree relative (parent, brother, sister, or child) of the other two;
At least two generations with cancer (such as a parent and child);
One or more cases of cancer diagnosed younger than age 50;
If you have a family history, it is important that you let your doctor know.
Ask for a referral to a genetic counsellor. This is an important step to help you understand the risks and benefits of genetic testing. For more information on hereditary and genetics specific information, please refer to these useful resources:
Hereditary Breast and Ovarian Cancer Society
FORCE: Facing Our Risk of Cancer Empowered
To find a genetic counsellor :
Contact your family physician as a first point of reference.
Also refer to:
Canadian Association of Genetic Counsellors
How do I know my risk?
Ultimately you must talk to your doctor to fully understand your individual risk for ovarian or any other cancer.
Learn more about risk factors for ovarian cancer:
Visit the Canadian Cancer Society's website