New drug for breast cancer

Researchers believe they have found a drug to prevent breast cancer.

Cancer Research UK is to start trials on 10,000 women as part of a 10-year study. It could reduce by 50 per cent their risk of developing the disease.

Professor Jack Cuzick of the University of London said: "The results of earlier trials with similar drugs showed there is a real possibility we can prevent breast cancer - but this new trial has the potential to be even more dramatic."

Called anastrozole, the drug works by stopping the production of oestrogen, the female hormone known to be a major cause of breast cancer - the most common cancer among women in Britain, accounting for almost one in three cases.

Many breast cancer patients are treated with tamoxifen, a hormone treatment developed over 30 years ago. It reduces the risk of cancers recurring by up to 40 per cent and is usually prescribed for five years after treatment.

Tamoxifen works by preventing the action of oestrogen on breast cells while allowing the hormone's beneficial effects - such as improving bone health - to continue. However, it is not usually prescribed as a preventative measure. It also has sideeffects including hot flushes, weight gain and a tendency to blood clots. The new drug does not cause these side-effects but could potentially lead to problems with bone density, which will be closely monitored.

Each year, about 30,000 postmenopausal women are diagnosed with breast cancer. Anastrozole has proved to be adept at treating those who already have the disease.

All 10,000 women on the trial will receive a bone scan and breast screening every 18 months to check on side-effects.

The trial will include 4,000 women already diagnosed with a non-invasive form of breast cancer. As well as being at increased risk, these women are more likely to develop tumours in the opposite breast, which researchers hope will help them spot problems early.

The other women in the trial will all be at high risk - for example, with a mother or sister who had breast cancer before the age of 50, or with two family members who suffered the disease.

More than 40 hospitals around the world are taking part in the study - 20 of them in the UK.

Cancer Research UK is appealing for women in at-risk groups to take part.

To be eligible, volunteers must be post-menopausal, not taking hormone therapy and be at least at twice the normal risk of breast cancer. For more information visit www.ibis-trial.com.