The active ingredient in Propecia, a baldness remedy approved by the Food and Drug Administration in 1997, is showing new promise as a way to prevent some prostate cancers. AP hide caption

itoggle caption AP

Sally O'Neill decided to have a double mastectomy rather than "do a wait-and-see." Richard Knox/NPR hide caption

itoggle caption Richard Knox/NPR

A billboard advertising robotic surgery hangs outside Boston's Fenway Park in 2009. Hospitals and doctors have heavily promoted robotic surgery. Charles Krupa/AP hide caption

itoggle caption Charles Krupa/AP

Terry Dyroff, of Silver Spring, Md., had a PSA blood test that led to a prostate biopsy. The biopsy found no cancer but did give him a life-threatening infection. Jose Luis Magana/AP hide caption

itoggle caption Jose Luis Magana/AP

Radiation therapist Jean Etienne holds a range compensator, which shapes the depth to which the proton beam enters a patient's body to target a tumor. Rebecca Davis/NPR hide caption

itoggle caption Rebecca Davis/NPR

Terry Dyroff, at home in Silver Spring, Md., got a PSA blood test that led to a prostate biopsy. The biopsy found no cancer, but it gave him a life-threatening infection. Jose Luis Magana/AP hide caption

itoggle caption Jose Luis Magana/AP