Routine mammograms may result in overdiagnosis of breast cancer

New Harvard School of Public Health research suggests that routine mammograms may in fact lead to a significant amount of overdiagnosis of disease that would otherwise have proved harmless. Based on a study of women in Norway, the researchers estimate that between 15 percent and 25 percent of breast cancer cases are overdiagnosed. "Mammography might not be appropriate for use in breast cancer screening because it cannot distinguish between progressive and non-progressive cancer," said lead author Mette Kalager, a visiting scientist at HSPH and a researcher at the Telemark Hospital in Norway. "Radiologists have been trained to find even the smallest of tumors in a bid to detect as many cancers as possible to be able to cure breast cancer. However, the present study adds to the increasing body of evidence that this practice has caused a problem for women -- diagnosis of breast cancer that wouldn't cause symptoms or death."