London - Breast screening can cut cancer deaths by 40 percent among middle-aged women, according to a study.
Data gathered from more than 10 million patients around the world shows that inviting women for regular mammograms really does save lives.
The study, published in the New England Journal of Medicine, will go some way towards ending a debate about the effectiveness of breast cancer screening. It found that women aged 50 to 69 – the age group invited for screening in Britain – have a 40 percent reduced chance of dying from breast cancer if they have a regular mammogram.
Some experts are sceptical about the benefits of widespread breast cancer screening. They say catching a tumour early can sometimes lead women into having potentially harmful treatments such as radiotherapy and chemotherapy unnecessarily.
There are also fears about false-positive results, in which women are wrongly told they might have breast cancer when, in fact, they do not.
The new data – compiled by 29 experts from 16 countries –suggests the benefits of screening women far outweigh the risks.
In the UK, the findings translate to about eight deaths prevented per 1 000 women regularly attending screening.
In Britain, women aged 50 to 70 are invited for a mammogram every three years. The study also found that women aged 70 to 74 have a slightly reduced chance of breast cancer deaths. They found little benefit in screening before the age of 50.
Overall, the researchers said screening detects breast cancers that would never have been diagnosed or caused harm if the women had not been screened.
Breast cancer is the most common type of cancer in the UK, and 50 000 women are diagnosed every year, the majority older than 50.
The research was co-ordinated by the International Agency for Research in Cancer, the World Health Organisation’s specialised cancer agency.
Professor Stephen Duffy of Queen Mary University of London, which contributed to the research, said: “The evidence proves screening is a vital tool in increasing early diagnosis of breast cancer and therefore reducing the number of deaths.
“Despite evidence that mammography screening is effective, we still need to carry out further research on alternative screening methods, such as the promising digital breast tomosynthesis, a newly developed form of 3D imaging which could potentially improve the accuracy of mammography in coping with more dense breast tissue.
“It is also vital we continue researching the most effective ways of screening women at high risk of breast cancer due to family history or genetic status. We need further evidence to fine-tune services offered to high-risk women in terms of different screening methods, from an earlier age and possibly at shorter intervals.”
Professor Julietta Patnick, director of the NHS Cancer Screening Programmes, said: “The team of experts working on this update weighed up both the benefits and harms of breast screening and found a net benefit from inviting women.”
Samia al Qadhi, chief executive at Breast Cancer Care, said: “The sooner breast cancer is diagnosed, the more effective treatment is likely to be. However, it’s estimated that for every life saved, three women will have unnecessary, often difficult treatment.
“Women must have access to clear information about screening so they can make an informed choice about whether to attend.”
Daily Mail