SPECIALIST WOMEN'S ULTRASOUND

Dr Michael Bethune MBBS FRANZCOG DDU COGU

Suite 12, 28-32 Arnold Street, Box Hill, 3128
Telephone: 03 9898 9055   Fax: 03 9890 8400

Ovarian Cancer Screening

What is ovarian cancer?

Ovarian cancer is the fourth most common cause of death from cancer in women. The risk of contracting ovarian cancer is increased if there is a family history of ovarian or breast cancer. The risk also increases in women after menopause.

How dangerous is ovarian cancer?

Most women who develop ovarian cancer have no symptoms until the disease is advanced. Survival depends on how early the disease is diagnosed. Advanced ovarian cancer has a very poor survival rate (less than 40% will survive beyond five years after the diagnosis is made). Early ovarian cancer has a very high survival rate. This has lead to a hunt for screening tests designed to detect early ovarian cancer, before symptoms have developed.

What screening tests are available for ovarian cancer?

There are presently two screening tests readily available for ovarian cancer. Neither is perfect, many experts suggest that women who are concerned about the risk of ovarian cancer have a combination of both screening tests. The screening tests presently available are a blood test (CA 125) and a transvaginal ultrasound.

What is CA 125?

CA 125 is a protein that is produced by some types of ovarian cancer. The risk of cancer increases as the level of CA125 increases in the blood stream. There are problems with using CA 125 to screen for ovarian cancer.

Firstly, the protein is elevated in a number of other conditions, many of which are benign and may be insignificant. This can lead to significant anxiety and the requirement for further testing to establish the cause of the elevated CA 125.

Secondly, CA 125 may not be elevated in up to half of early ovarian cancers, leading to an inability to detect an ovarian cancer at an easily treatable stage.

How does the transvaginal ultrasound aid in the detection ovarian cancer?

Transvaginal ultrasound is very good at detecting small lesions within the ovary. Furthermore, a skilled operator is often able to get an indication of the likelihood of a lesion being a cancer from its appearance.

Unfortunately, there is also a risk of detecting benign or insignificant changes within the ovaries. As with elevated CA 125 this may lead to the requirement for further testing, and possibly even gynaecological surgery. The risk of having this sort of falsely abnormal test result (false positive) is greatly reduced by having the ultrasound performed at a clinic experienced in the assessment of ovarian disease.

Do I need to have ovarian cancer screening?

Unlike pap smears and mammograms (in older women) ovarian cancer screening is not compulsory. Whether or not you wish to be screened is a personal decision based on your own level of concern about the disease. Your general practitioner or gynaecologist may be able to give you an idea as to your personal level of risk for contracting ovarian cancer.

How frequently should ovarian cancer screening be performed?

Most gynaecological cancer specialists recommend that women who are at increased risk of contracting ovarian cancer have yearly screening. These women would have the CA 125 blood test and also a transvaginal ultrasound performed by an expert in gynaecological ultrasound once each year. It may be a useful aide-de-memoir to link this testing to a special yearly event, for example, near your birthday.