Brussels, 25 Apr 2003
Dutch and Swedish researchers have found that since the introduction of mammography screening services, deaths from breast cancer have reduced considerably.
A Swedish study, led by Laszlo Tabar from the Falun hospital, compared the number of deaths from breast cancer in the 20 years before and after the introduction of screening in two Swedish counties.
More than 200,000 women with breast cancer between the ages of 20 and 69 were involved in the study.
'We aimed to assess the long-term effect of mammographic screening on death from breast cancer, taking into account potential biases from self-selection, changes in breast cancer incidence, and classification of cause of death,' said Dr Tabar.
The study found that breast cancer mortality was reduced by 44 per cent in women between 40 and 69 years old who had received mammography screening. Conversely, death rates only fell by 16 per cent for women who had not been screened.
In the case of younger women, aged between 40 and 49, death rates fell by 48 per cent, compared with 19 per cent for those who had undergone a mammography.
Similarly, a study carried out in the Netherlands found that routine screening could significantly reduce mortality rated in women aged between 55 and 74. Led by Suzie Otto from the department of public health, the scientific team analysed data for more than 23,000 women who died of breast cancer in the specified age group to investigate time trends in breast cancer mortality and the effect of screening.
Compared with breast cancer mortality in the period 1986 to 1988, rates significantly fell from 1997 onwards by nearly 20 per cent. Dr Otto also discovered that since the introduction of screening services, mortality rates have been decreasing by almost 2 per cent per year.
The results from both tests suggest that screening programmes can dramatically reduce deaths from breast cancer. They also dispel any doubts as to the potential value of mammographies for breast cancer prevention.