THE introduction of breast screening has led to a drop in mastectomy rates, not an increase, as some scientists have suggested, according to a new study.

Researchers, who studied almost 60,000 women, found the rates of breast removal surgery fell by almost half following the introduction of a screening programme.

This goes against recent suggestions that screening increases the number of mastectomies because of over-diagnosis.

In the Northern and Yorkshire region, the number of women taking up breast screening opportunities has increased steadily over the past six years.

By March 2001, 71.8 per cent of women aged 50 to 64 had been screened at least once in the previous three years, compared to 70.1 per cent in March the previous year.

The new study, published in the British Medical Journal yesterday, involved women aged 50 to 69 in Florence, Italy.

The women were invited for screening between 1990 and 1996 and to subsequent screens at two-year intervals.

The researchers found the rates of mastectomies declined by 40 per cent following the introduction of the screening programme while the rates of breast conserving surgery increased by about 50 per cent over the same period.

The researchers concluded that screening detects cancer early so women can be treated with minor surgery that conserves the breast, rather than radical surgery that results in its removal.

Study author Dr Stephen Duffy, of Cancer Research, said: "Some scientists believe screening programmes could be harmful to women by increasing the rates of aggressive treatments, such as mastectomy. But this study shows that screening actually reduces the need for major surgery by detecting the disease before it spreads."

He said it showed that screening, as well as saving lives by detecting cancer early, could help women avoid the traumatic experience of having their breast removed.