A report just published in the Journal of the American Medical Association's Archives of Internal Medicine (Arch Intern Med. 2008;168[21]:2302-2303) reaches a startling conclusion. Breast cancer rates increased significantly in four Norwegian counties after women there began getting mammograms every two years. In fact, according to background information in the study, the start of screening mammography programs throughout Europe has been associated with increased incidence of breast cancer.

This raises some obvious and worrisome questions: Did the x-rays and/or the sometimes torturous compression of breasts during mammography actually spur cancer to develop? Or does this just look like an increase in the disease rate because mammography is simply identifying more cases of breast cancer?