A major US breast cancer foundation known for its high-profile 'pink ribbon' campaign has been overselling pre-emptive mammography and understating the risks, medical experts accused on Friday.
The Susan G. Komen for the Cure foundation uses misleading statistics in its pro-screening campaigns, two doctors from The Dartmouth Institute for Health Policy and Clinical Practice in New Hampshire wrote in the BMJ medical journal.
"Unfortunately, there is a big mismatch between the strength of evidence in support of screening and the strength of Komen's advocacy for it," professors Steven Woloshin and Lisa Schwartz wrote.
They take issue with a Komen poster comparing the 98-percent five-year survival rate for breast cancer when caught early, with a of 23-percent rate for later diagnosis.
Comparing the two figures did not tell you anything about the benefits of screening, they argued, and in reality a mammogram only narrowly decreases the chances that a 50-year-old woman will die from breast cancer within 10 years from 0.53 percent to 0.46 percent.
Breast cancer treatments are more effective today, and some question whether screening mammography has any benefit whatsoever, wrote the pair.
They accused Komen of overlooking the potential harms, with up to half of women screened annually over 10 years experiencing at least one false alarm that requires a biopsy.
Screening also results in overdiagnosis -- detecting cancers that would never have killed or even caused symptoms in a person's lifetime, and unnecessary treatment.
"The Komen advertisement campaign failed to provide the facts," said the piece. "Worse, it undermined decision making by misusing statistics to generate false hope about the benefit of mammography screening."
In 2010, a report in the New England Journal of Medicine said mammograms have only a "modest" impact on reducing breast cancer deaths.
Komen, in a response to the BMJ comment, insisted that early detection enables early treatment, which gives the best shot at survival.
"Everyone agrees that mammography isn't perfect, but it's the best widely available detection tool that we have today," said Chandini Portteus, the foundation's vice president of research, evaluation and scientific programmes.
"We've said for years that science has to do better, which is why Komen is putting millions of dollars into research to detect breast cancer before symptoms start, through biomarkers, for example."
In February, Komen was embroiled in a controversy over its decision to stop funding for an abortion clinic group in the United States.