Breast cancer screening programmes save two lives for every woman subjected to ‘unnecessary’ treatment by the procedure, researchers have claimed.
Researchers at the Wolfson Institute of Preventive Medicine at Barts and the London School of Medicine and Dentistry have found that 5.7 deaths from breast cancer were prevented for every 1,000 women screened over 20 years in England, with cases of over-diagnosis estimated at 2.3 per 1,000 examined.
“The benefit of mammographic screening in terms of lives saved is greater in absolute terms than the harm in terms of over-diagnosis,” the authors said. “Between 2 and 2.5 lives are saved for every over-diagnosed case.”
The study comes after Danish experts last week cast doubt on the benefits of breast cancer screening programmes, saying that the difference in death rate between those screened and those not screened was negligible.
Scientists are currently unable to distinguish between threatening and non-threatening cancers, meaning all are treated. The problem exists because some forms of the disease grow so slowly as to cause no harm.