Ovarian cancer: what you need to know
What is ovarian cancer?
Ovarian cancer is cancer of a woman’s ovary or ovaries. The ovaries are located on either side of the uterus (womb) and produce eggs (ova) and female sex hormones. Ovarian cancer most commonly affects women who've passed the menopause, but younger women can also be affected. It is the 9th most common cancer affecting women in Australia.
What are the symptoms of ovarian cancer?
Some of the possible symptoms of ovarian cancer include:
- pelvic pain or discomfort;
- abdominal bloating, swelling or fullness;
- nausea and loss of appetite or feeling full quickly;
- changes in bladder habits, including urinary urgency (an urgent need to empty the bladder);
- changes in bowel habits, including diarrhoea or constipation;
- changes in your menstrual cycle, or bleeding after you have gone through menopause;
- low back pain;
- persistent unexplained tiredness; and
- pain during intercourse.
While these non-specific symptoms are often due to less serious diseases, they can indicate ovarian cancer, especially if the symptoms are persistent or getting worse. But because many women don’t experience any symptoms at all early on, and if they do, the symptoms are often vague and tend to mimic other problems, ovarian cancer is sometimes not detected until the cancer is advanced and at a stage when cure is less likely.
Who is at risk of ovarian cancer?
Some factors may put you at a slightly higher risk of developing ovarian cancer, while other factors can reduce your risk. Factors that can increase your risk include:
- age - your risk increases as you get older, with more than 80 per cent of ovarian cancers occurring in women over the age of 50;
- a family history of ovarian or breast cancer;
- changes (mutations) in the genes BRCA1 or BRCA2, which can also be associated with breast cancer;
- infertility; and
- taking oestrogen-only hormone replacement therapy for an extended length of time.
Having at least one pregnancy seems to reduce your risk of ovarian cancer, as does breast feeding your baby. Similarly, taking the oral contraceptive pill may decrease your risk. In fact, taking the pill for 5 or more years can reduce the risk of ovarian cancer by 30 to 40 per cent.
How is ovarian cancer diagnosed?
There are a number of tests that are used to help diagnose ovarian cancer, including an ultrasound (which may be performed through the vagina) and blood tests such as the CA125 test. If these tests suggest that ovarian cancer is likely, an operation is usually needed to confirm the diagnosis. If an ovarian tumour is discovered during the operation, surgery to remove the cancer can be performed at the same time.
There is no reliable way at present to screen women who don’t have symptoms for ovarian cancer. The CA125 test is not a good screening test as you may have raised CA125 levels without having cancer (e.g. if you are menstruating or have endometriosis or ovarian cysts), or CA125 levels may be normal when cancer is present. The Pap smear test for cervical cancer does not detect ovarian cancer.
What treatments are available?
In most cases, ovarian cancer is treated initially with surgery to remove the cancer, followed by chemotherapy to kill any remaining cancer cells in the body. Radiotherapy is also sometimes used to treat ovarian cancer.
What is the outlook for women with ovarian cancer?
The outlook for women with ovarian cancer depends on the type of tumour and whether it has spread to other areas of the body. There are 4 main types of ovarian tumours:
- epithelial tumours, which are the most common type and usually affect older women;
- germ cell tumours, which are more common in younger women;
- stromal tumours, which are rare and can occur at any age; and
- borderline tumours, which don’t spread as quickly as other forms of ovarian cancer.
Germ cell tumours, stromal tumours and borderline tumours respond well to treatment and can usually be cured. Unfortunately, the outlook for women with epithelial tumours is not always as good; however, women with early epithelial tumours that have not spread have a good chance of complete recovery.
2. Cancer Council Australia. Early detection of ovarian cancer (last updated 12 Feb 2010). http://www.cancer.org.au/cancersmartlifestyle/Earlydetection/Earlydetectionfactssheets/ED_ovarian_cancer.htm (accessed Jan 2011).
3. Cancer Council Australia. After a diagnosis of ovarian cancer (last updated 24 May 2010). http://www.cancer.org.au/aboutcancer/afteradiagnosis/After_diagnosis_ovarian_cancer.htm (accessed Jan 2011).
4. Ovarian Cancer Australia. Ovarian cancer awareness brochure. http://www.ovariancancer.net.au/awareness/awareness-resources/ (accessed Jan 2011).
5. Jean Hailes Foundation for Women's Health. Ovarian cancer: what every woman should know (last updated 17 Dec 2009). http://www.healthforwomen.org.au/health-issues/25-ovarian-cancer (accessed Jan 2011).
6. MayoClinic.com. Ovarian cancer (last updated 11 Nov 2010). http://www.mayoclinic.com/health/ovarian-cancer/DS00293 (accessed Jan 2011).
7. Kehoe S, Morrison J. Ovarian cancer (advanced) (last updated 16 Jan 2009). Clinical Evidence (online). http://clinicalevidence.bmj.com/ceweb/conditions/woh/0816/0816.jsp (accessed Jan 2011).
8. Faluyi O, Mackean M, Gourley C, et al. Interventions for the treatment of borderline ovarian tumours. Cochrane Database Syst Rev 2010; 9: CD007696. doi: 10.1002/14651858.CD007696.pub2. http://onlinelibrary.wiley.com/o/cochrane/clsysrev/articles/CD007696/frame.html (accessed Jan 2011).
9. Australian Institute of Health and Welfare & National Breast and Ovarian Cancer Centre. Ovarian cancer in Australia: an overview, 2010. Cancer series no. 52. Cat. no. CAN 48. Canberra: AIHW; 2010. http://www.aihw.gov.au/publications/index.cfm/title/11158 (accessed Jan 2011).
10. National Cancer Institute (US). What you need to know about ovarian cancer (last updated 17 Jul 2006). http://www.cancer.gov/cancertopics/wyntk/ovary (accessed Jan 2011).