Frequently Asked Questions


Epithelial ovarian cancer is the deadliest cancer of the female reproductive system and is the fifth leading cause of cancer-related death in Canadian women. Ovarian cancer is the uncontrolled growth of abnormal cells within the ovaries.

There are five main types of epithelial ovarian cancer. High-grade serous cancer (HGSC) is the most common and deadliest form of ovarian cancer. Go to the What Is Ovarian Cancer? section for more information.

Most women with ovarian cancer go to see a doctor with general symptoms such as bloating, feeling full quickly after eating, needing to urinate often and pain or a mass in their pelvic area. At first, a woman may not notice these symptoms, but as the cancer grows the symptoms become worse. There are other medical conditions besides ovarian cancer that may cause these symptoms. Your doctor will do further investigations, such as imaging and blood tests to find out the cause.

If there is a high suspicion of ovarian cancer, a final diagnosis of ovarian cancer is made during surgery to remove the ovaries and any other affected tissue. As part of this surgery, a little piece of tissue is taken from the ovaries and looked at under a microscope to identify cancer cells.

Ovarian cancer is treated with surgery and chemotherapy. The decision on what type of therapy to have first is up to your doctor. Chemotherapy, a type of medication that kills cancer cells, may be needed in many cases. The two main anti-cancer drugs given during chemotherapy for ovarian cancer are called carboplatin and paclitaxel (Taxol).

The exact cause of ovarian cancer is not completely understood. The latest research shows that most cases of HGSC begin in the part of the fallopian tubes that is right next to the surface of the ovary. These cancerous cells can easily spread to the ovary, where the cancer develops further.

There are factors that increase the risk of developing ovarian cancer, including different types of inherited genetic mutations that are passed on through generations within a family. These include the BRCA1 and BRCA2 genes and other genes that are under investigation.

The strongest risk factors associated with ovarian cancer development are a family history of breast or ovarian cancer and/or inheritance of a mutation in the BRCA1 or BRCA2 genes. Inheritance of mutations in other genes, such as those within the mismatch repair or Fanconi Anemia pathways, may also increase ovarian cancer to a lesser degree.

Ovulation is the monthly release of an egg from the ovary. The number of times a woman ovulates during her lifetime can influence her risk for ovarian cancer: the more ovulations a woman has in her lifetime, the higher the risk of developing ovarian cancer. Taking the birth control pill, having children and breast feeding are all factors that lower the number of times a woman ovulates during her lifetime. Tubal ligation, sometimes referred to as “tying your tubes”, has also been associated with a lower ovarian cancer risk. There is some scientific evidence that suggests taking non-steroidal anti-inflammatory drugs such as aspirin can lower a woman’s risk for ovarian cancer by decreasing inflammation.  

If you have a first-degree relative with HGSC and have confirmed that they have a BRCA1 or BRCA2 gene mutation, you have a 50% chance of having the same mutation. If you don’t know whether your first-degree relative had a mutation, there may be a 20-25% chance that their cancer was due to a genetic mutation. In that case, you may have a 10-12.5% chance of having a BRCA1 or BRCA2 gene mutation.

You can find out if you have a BRCA1 or BRCA2 gene mutation by providing a blood sample for genetic testing. Genetic testing does not test for ovarian cancer itself but rather it tests for risk of developing cancer. Go to Do I Qualify? to see if you could be at increased risk for ovarian cancer and should get tested.

The lifetime risk for developing ovarian cancer in a woman with a BRCA1 gene mutation is between 20-40% and between 10-20% for a woman with a BRCA2 gene mutation.

The most effective way to reduce the risk of ovarian cancer in women with cancer-predisposing mutations is by removing the ovaries and fallopian tubes. This surgery is called salpingo-oophorectomy. Although it can be difficult to determine the best age for this type of surgery, a salpingo-oophorectomy should occur before the age of 40 in order to have the greatest effect on risk reduction. Because the potential to prevent ovarian cancer with surgery decreases as a woman gets older, there is research to suggest that a woman should have the surgery by age 35. Taking the birth control pill may also lower the risk for ovarian cancer in women with and without BRCA1 or BRCA2 gene mutations. A clinical recommendation to take birth control pills to prevent ovarian cancer is being considered.

Studies to date have estimated that the risk of ovarian cancer after surgery is 0.5-4%, which is similar to the risk in women who do not have BRCA1 or BRCA2 gene mutations. The risk after surgery is dependent on the age at which surgery is performed.
In a small percentage of women, ovarian cancer is discovered during their risk-reducing surgery. However, since the majority of these cases are found at an early stage, these women have an excellent prognosis over a five year period. In these cases, >90% of women are still alive 5 years after their diagnosis.

If you have a significant family history of ovarian or breast cancer but your genetic testing results for BRCA1 or BRCA2 mutations are negative, it means that you do not have the mutation; however, other relatives may have the BRCA1 or BRCA2 gene mutation and should talk to a genetic counsellor about genetic testing.

A BRCA1 or BRCA2 genetic test looks for BRCA1 and BRCA2 gene mutations only. If you test negative for these mutations, there is a possibility that you have a mutation in other ovarian cancer risk genes, such as those in the mismatch repair or Fanconi Anemia pathways. The Prevent Ovarian Cancer Program will test for BRCA1 or BRCA2 gene mutations in addition to these other ovarian cancer risk genes.

Yes, men can also inherit mutations in BRCA1 or BRCA2 genes and can pass them on to their children. Men with BRCA1 or BRCA2 mutations are at increased risk of prostate cancer. Men with BRCA2 mutations may also have an increased risk of pancreatic cancer, male breast cancer and melanoma.

If a daughter inherits a BRCA1 or BRCA2 gene mutation from her father, she is at increased risk for ovarian and breast cancer. The risks of breast and ovarian cancer are the same whether a BRCA1 or BRCA2 gene mutation is inherited from the mother or father. This is why it is important to look at the entire family history, both male and female, in order to generate an accurate family tree for review during genetic counselling.

Type of Cancer

Risk in general population

Risk if have mutation in BRCA 1 or BRCA2

Breast Cancer



Ovarian Cancer



Prostate Cancer



*Individuals with a BRCA2 mutation may also have increased risks of developing male breast cancer, melanoma and pancreatic cancers.

If you have a BRCA1 or BRCA2 gene mutation, the genetic counsellor will discuss screening and prevention strategies for all cancers, including ovarian cancer. Click to learn more about breast cancer risk.

If you have a family history of ovarian cancer but do not live in Ontario, you can talk to your doctor to see if you are eligible for genetic testing in your province. Visit the resource page to find information about genetic testing clinics in all provinces.

The Genetic testing included in the Prevent Ovarian Cancer Program is limited to women who have a first-degree relative (mother, sister, daughter) found to have HGSC because these women have the highest chance of  inheriting a BRCA1 or BRCA2 gene mutation. If your relative was diagnosed with a non-serous type of ovarian cancer, there is only a very small chance that you would have inherited a BRCA1 or BRCA2 gene mutation.   If you are concerned about your family history of cancer, you may ask your doctor to refer you to a genetic counsellor outside of this program. 

If you have been diagnosed with HGSC yourself, you are eligible for BRCA1 or BRCA2 genetic testing based on Ontario Ministry of Health and Long-Term Care criteria. If you have been diagnosed with a non-serous type of ovarian cancer you may be eligible for genetic testing for BRCA1 or BRCA2 mutations or for Lynch Syndrome, which is another type of cancer-susceptibility syndrome that occurs in a small proportion of patients. Eligibility for testing may depend on additional personal and/or family history of cancer.

Your relative likely had some form of diagnosis either through testing the fluid in her abdomen or a biopsy.  These results would have been documented in a pathology report which can be used to determine if you are eligible for the program.

No. We can either refer you to a local hospital for genetic counselling, or host all appointments over the phone. Your blood sample will be collected at a local clinic and sent to us for genetic testing. You do not have to physically come to Toronto for any appointments. 

Women diagnosed with serous ovarian cancer are eligible for genetic testing through the Ministry of Health and may have this arranged through a local genetics clinic. Visit the Canadian Association of Genetic Counsellors to find a list of genetics clinics in Canada.

The current program is offering genetic testing to women who have a first degree relative with ovarian cancer, but who may not be eligible for genetic testing through the Ministry of Health. Your female first degree relatives (mother, sisters, and daughters) may qualify for the program. Visit Do I Qualify? to find out more.