Western Australian women are needed to join an international, pioneering study investigating whether breast cancer could be prevented by a drug known as anastrozole.
Researchers from The University of Western Australia and Sir Charles Gairdner Hospital in Perth are joining more than 30 hospitals across Australia and New Zealand and hundreds of institutions worldwide by taking part in the International Breast Cancer Intervention Study (IBIS-II). The trial is being conducted at SCGH.
It is funded by the National Health and Medical Research Council with support from Cancer Council WA.
Previous research using anastrozole as a treatment for early breast cancer suggests that it could prevent up to 70 percent of new tumours occurring in women at increased risk, or 300,000 breast cancers per year, worldwide.
IBIS-II Principal Investigator, UWA Winthrop Professor Christobel Saunders, said that the study had the potential to benefit future generations of women. She urged local women to get involved if they were eligible.
"It's important that women in the area have access to the study and have the opportunity to contribute to vital breast cancer prevention research," she said.
"The findings from this research may provide a new approach to prevent breast cancer, not only for women today, but also for their daughters and granddaughters in the future."
The global study is seeking 8,000 women. Worldwide, over 6,100 women have already joined IBIS-II, including more than 820 from Australia and New Zealand, but many more volunteers are still needed before the study closes in December 2011.
To join the study, women must be postmenopausal, aged between 40 and 70, and have a family history of breast cancer. Women joining the study take a tablet a day for five years and receive a bone health check when they begin the study. They receive high-quality care including an annual check with a clinician (twice in the first year).
The study is coordinated in Australia and New Zealand by the Australian New Zealand Breast Cancer Trials Group and is coordinated internationally by Cancer Research UK.
For more information about joining the IBIS-II study Freecall 1800 640 709 or register your interest online.
Background: The International Breast Cancer Intervention Study
The IBIS-II study has grown from the IBIS-I Study. The International Breast Cancer Intervention Study I (IBIS-I) was designed to investigate the use of tamoxifen in preventing breast cancer in women with a higher risk of developing the disease.
Recruitment of women to IBIS-I ended in March 2001 and the results of the study showed that tamoxifen reduced the incidence of breast cancer by one third in these high risk women but with some serious side effects.
IBIS-II was designed to continue the work started in IBIS-I by examining the role of anastrozole in the prevention of breast cancer.
- Researchers are recruiting 4000 post-menopausal women worldwide at a high risk of breast cancer.
- The study has been designed to investigate whether anastrozole can be used effectively to prevent breast cancer, based on comparison with a dummy drug (placebo).
- Women on the trial will either take anastrozole or placebo for 5 years.
- The IBIS-II trial will be recruiting women until December 2011.
- Recent research has shown that anastrozole is more effective than tamoxifen at preventing the return of cancer in post-menopausal women who have an early breast cancer removed. In these women it reduces their risk of developing a new cancer in the opposite (contralateral) breast by 53% compared to tamoxifen.
- This is a very strong indicator that anastrozole will be more effective than tamoxifen in preventing breast cancer in women who have not yet developed the disease.
- Research has also shown that anastrozole has fewer serious side effects than tamoxifen, which can cause womb cancer and blood clots. Anastrozole does have some side effects such as hot flushes, vaginal dryness and an increase risk of osteoporosis.
- This supporting evidence has led to the start of the IBIS-II prevention study, a trial to investigate whether anastrozole could prevent also breast cancer but with fewer side effects than tamoxifen.
- Anastrozole does increase the risk of bone fractures in postmenopausal women.
- Women who join the prevention trial have a spinal x-ray and a bone density scan (DXA scan) to ensure that they have a safe level of bone density. Those women who do not have a safe level will be told that they can only join the study if they are willing to take a bisphosphonate (bone strength medication). In this way, those women at high risk of bone fractures are identified and can be offered a preventive treatment such as a bisphosphonate.
Women cannot enter this study if they:
- Have had any other cancer in the last 5 years (except non-melanoma skin cancer or carcinoma in situ of the cervix)
- Have taken tamoxifen or raloxifene for 6 months within the last 5 years. Women who took part in IBIS-I are eligible if they have been off medication for more than 5 years.
- Want to carry on taking HRT (hormone replacement therapy) that contains oestrogen
- Have had (or are planning to have) a breast(s) removed (a mastectomy) to try and prevent breast cancer
- Have any other serious medical conditions such as heart disease.
Women should discuss all options with their doctor before making a decision to take part in IBIS-II.