Dr. Jim Olson meets with Carver Faull at Seattle Children's Hospital in August. Carver, now 12, had surgery to remove a brain tumor in 2012. Matthew Ryan Williams for NPR hide caption

itoggle caption Matthew Ryan Williams for NPR

The image on the left is a piece of lung tissue that contains a tumor viewed under normal white light. The right image shows the same piece of tissue after Tumor Paint has been applied. Here it's viewed under infrared light. Areas that are more red and yellow show a concentration of the paint, which means they are more likely to be cancerous. Courtesy of Julie Novak/Blaze Bioscience hide caption

itoggle caption Courtesy of Julie Novak/Blaze Bioscience

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

Laura Molina, 9, shows the mask she created expressing the feeling of "sadness." Her mother is being treated for breast cancer at the Lyndon B. Johnson public hospital in Houston. Carrie Feibel/KUHF hide caption

itoggle caption Carrie Feibel/KUHF

Some images of lung cancer are clear cut. But in many others, a nodule on the screen turns out not to be cancer at all. iStockphoto.com hide caption

itoggle caption iStockphoto.com

Vaccines against the HPV virus are already used to prevent cervical and anal cancer. Harry Cabluck/AP hide caption

itoggle caption Harry Cabluck/AP

A 13-year-old girl gets an HPV vaccination from Judith Schaechter, a pediatrician at the University of Miami, in 2011. Joe Raedle/Getty Images hide caption

itoggle caption Joe Raedle/Getty Images