Karen Lindsfor, a professor of radiology and chief of breast imaging at the University of California, Davis Medical Center, examines the mammogram of a patient with heterogeneously dense breast tissue. Lindfors is among those doctors who say there was insufficient evidence to support the idea that additional screenings would detect cancers earlier. Rich Pedroncelli/AP hide caption

itoggle caption Rich Pedroncelli/AP

Staying fit and eating well can help cancer survivors, too, a review of the latest evidence shows. Lucy Pemoni/AP hide caption

itoggle caption Lucy Pemoni/AP

Dr. Steven Birnbaum positions a patient inside a CT scanner at Southern New Hampshire Medical Center in Nashua, N.H., in June 2010. Jim Cole/AP hide caption

itoggle caption Jim Cole/AP

This illustration shows a device made by MammoSite used to deliver targeted doses of radiation as part of brachytherapy. Courtesy Radiological Society of North America hide caption

itoggle caption Courtesy Radiological Society of North America

The danger of death by heart attack or suicide is greatest in the first week after a cancer diagnosis. Max Delson Martins Santos/iStockphoto.com hide caption

itoggle caption Max Delson Martins Santos/iStockphoto.com

Aspirin helps reduce the risk of cardiovascular disease, but the jury's still out on cancer. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Cells gathered during a Pap test. Those on the left are normal, and those on the right are infected with human papillomavirus. Ed Uthman/Wikimedia Commons hide caption

itoggle caption Ed Uthman/Wikimedia Commons

Coca-Cola says the caramel coloring in its signature soda has always been safe. OmerSukruGoksu/iStockphoto.com hide caption

itoggle caption OmerSukruGoksu/iStockphoto.com

Many hospitals are perilously close to running out of a form of methotrexate that's necessary to inject in high doses to treat certain forms of cancer. iStockphoto.com hide caption

itoggle caption iStockphoto.com