Ovarian cancer is a group of diseases that arise from the ovaries, which are the female reproductive organs that produce eggs (ova) and the hormones estrogen and progesterone. It is the second most common gynecological cancer in the United States and has the highest mortality rate. The symptoms of ovarian cancer can be non-specific and mimic other conditions, meaning patients can present late when the disease has already spread.
According to the National Cancer Institute’s Surveillance, Epidemiology and End Results Program, 55% of women with ovarian cancer have distant (metastatic, which has spread) disease at the time of diagnosis. The five-year survival rate of patients with distant disease is just 31.5% compared to 91.4% for those with localized disease.
These statistics emphasize the importance of being educated and aware of risk factors as well as the symptoms and signs of ovarian cancer. There is no single method for ovarian cancer prevention and no single effective screening test. However, there are options based on an individual's risk. Read on to learn more about ovarian cancer risk factors and ovarian cancer prevention.
Ovarian cancer arises from the uncontrolled growth of cells in the ovaries. There are many types of ovarian cancer — the most common being epithelial ovarian cancer, which accounts for 90%, according to the American Cancer Society. Rarer types include germ cell and stromal tumors, which tend to occur in younger women. Ovarian cancer treatment typically involves surgery and chemotherapy.
Although we are aware of many risk factors, it’s not known exactly what causes ovarian cancer and there have been proposed theories based on epidemiological studies.
It has been noted that risk-reducing factors, such as pregnancy and the use of birth control pills, decrease the number of times the ovary releases an egg (ovulation). As such, researchers have theorized that ovulation plays a role in the development of the disease.
Other factors that have been shown to reduce the risk of ovarian cancer is removal of the uterus (hysterectomy) and tubal ligation (also known as tubal sterilization or “getting your tubes tied”), which is a process of blocking the fallopian tubes to prevent the egg traveling to the uterus. It has been proposed that carcinogens may enter the body through the vagina to the uterus and subsequently the ovaries, thus increasing cancer risk. Therefore, it is thought that a hysterectomy or tubal ligation prevents the passage of carcinogens to the ovaries and reduces this risk.
Moreover, women who have had a full-term pregnancy before the age of 26 have a lower risk of ovarian cancer and this risk decreases with further full-term pregnancies. Breastfeeding has also been shown to reduce the risk. The exact cause of ovarian cancer, however, remains unknown and cancer research is ongoing.
Several factors have been discovered that put women at an increased risk of ovarian cancer. Those discussed below apply to epithelial ovarian cancer. Awareness of your risk is key. If you are unsure, take the Ezra five-minute quiz.
Here are some known risk factors for ovarian cancer:
Unfortunately, there’s no single ovarian cancer prevention method. Certain strategies are available depending on the underlying risk factors and these should be discussed with a healthcare professional.
If your family history suggests a possible underlying hereditary cancer syndrome, you may want to consider genetic counseling. This involves an assessment of your family and personal medical history and a discussion regarding the risks and benefits of genetic testing. The session is undertaken by a trained genetic counselor.
Knowing the presence of a genetic mutation that causes a predisposition to certain cancers can affect the individual and their family. Therefore, the decision to undergo testing should not be taken lightly.
Having this information, however, can allow women to make informed decisions regarding certain preventative strategies. For instance, risk-reducing or prophylactic gynecologic surgery may be considered. This involves removing the ovaries (oophrectomy) and/or the fallopian tubes (salpingectomy). A bilateral salpingo-oophorectomy might be recommended for high-risk women who don’t intend to have more children. These methods do not come without risks and implications and should be discussed at length with a healthcare professional.
As discussed previously, the use of birth control pills or oral contraceptives reduces the risk of ovarian cancer, and women at high risk may opt to take these as a preventative measure. That said, birth control pills have side effects, including a slightly higher risk of blood clots and breast cancer. The decision to commence such treatment should be discussed with a healthcare professional.
Despite extensive research, there is no single effective screening test for ovarian cancer. A blood test can be used to look for the presence of a protein called Ca-125. However, this test has a low sensitivity and can be positive in patients with benign conditions like endometriosis and pelvic inflammatory disease.
Still, it’s useful in monitoring cancer care treatment response in patients with the disease. Another method that has been used is a transvaginal ultrasound scan (TVUS). TVUS is helpful in detecting a mass but cannot tell if it is benign or cancerous. Most ovarian masses detected using TVUS are benign (non-cancerous).
In women who are at high risk, for example, those who have the BRCA1 or BRCA2 mutation, some centers recommend a TVUS and Ca-125 blood test as screening tests. But research has shown that using these screening tests does not reduce the risk of dying from ovarian cancer. In women at average risk of ovarian cancer, there’s no recommended screening test. In fact, clinical trials have shown that screening in this population leads to more tests and more surgeries and does not reduce the risk of death.
The most important action you can take is to be aware of the signs and symptoms of ovarian cancer and know what is normal for your body. Symptoms due to cancer tend to persist and worsen over time, so always seek medical attention if you’re concerned. It’s also important to understand your individual risk and family history. Learn more about cancer screenings.
Ovarian cancer is most commonly diagnosed in the later stages when it’s more difficult to treat and survival outcomes are poor. Moreover, no effective screening test exists but TVUS or Ca-125 may be recommended in high-risk women.
It’s vital to understand your risk and know your body to identify any symptoms early. Some risk factors, such as age, can’t be altered. However, others, such as lifestyle habits, can. Engage in regular physical activity and eat a healthy, varied diet. It’s always a good idea to understand the relationship between your body and food to maintain a healthy diet.
Alternatively, if you want to be proactive about your health status before any symptoms arise, consider booking an Ezra Full Body MRI. This painless, non-invasive scan gives information on up to 13 different organs, including the ovaries.