One of the questions that arises regularly within our group is the value (or otherwise) of routine screening for breast cancer in preventing mortality. The subject is discussed here in a detailed report (including results from several large-scale studies) that’s up on the National Breast Cancer Coalition website.
The report concludes that:
‘Evidence from studies of varied quality indicate that, overall, mammography screening has a modest effect on breast cancer mortality. When analyzed in absolute terms, the death rate is reduced by just 0.05%. Like with all medical interventions, there are harms associated with screening mammography such as misdiagnosis and overtreatment. Two comprehensive reviews of the evidence conclude that the overall impact in mortality is small and biases in the trials could either “erase or create it.” Women should discuss with their doctors their own risk profile, the potential benefits, harms, and complexities of screening mammography, and make informed decisions about screening. Mammography may provide benefits for some women, but it may also harm others.
NBCC embraces a philosophy of evidence-based health care, and has long raised questions about the value of mammography screening and other interventions. Women need honest information regarding the value of all medical interventions. Public health resources need to be used with certainty to improve the public’s health. The reality is that screening has not been effective. While the incidence of ductal carcinoma in situ and localized invasive breast cancer increased substantially as a result of screening programs, the incidence of regional or distant stage disease has not.
NBCC believes that in order to make true progress in breast cancer we need to better understand what causes this disease and how to prevent it, what puts individual women at risk beyond the known risk factors, how different types of breast cancer behave, which treatments are appropriate and effective for each type of breast cancer, and how to prevent metastasis. With that knowledge, and with improved screening methodologies, we could target screening to those who would truly benefit from it.’
Women need to know the truth about mammography screening, including its potential benefits, harms, and limitations. As breast cancer activists, NBCC welcomes discussion of the effectiveness of all breast cancer interventions. We must recognize that we do not know how to detect breast cancer truly early, how to prevent or cure this disease, and focus our attention on getting these answers.