An architectural rendering of the Cleveland Clinic's planned cancer center. Courtesy of the Cleveland Clinic hide caption

itoggle caption Courtesy of the Cleveland Clinic

Dr. George Papanicolaou discovered that it was possible to detect cancer by inspecting cervical cells. The Pap smear, the cervical cancer screening test, is named after him. American Cancer Society/AP hide caption

itoggle caption American Cancer Society/AP

Science-based guidelines say there's no benefit to getting an EKG of heart activity before routine cataract surgery — even if the patient is old. But most doctors order such tests anyway. Bull's Eye/ImageZoo/Corbis hide caption

itoggle caption Bull's Eye/ImageZoo/Corbis

Catharine Becker of Fullerton, Calif., was diagnosed with stage 3 breast cancer at 43 despite having a clean mammogram. The mother of three didn't know she had dense breast tissue until after she was diagnosed. Heidi de Marco/Kaiser Health News hide caption

itoggle caption Heidi de Marco/Kaiser Health News

Sequencing the genes of a cancer cell turns up lots of genetic mutations — but some of them are harmless. The goal is to figure out which mutations are the troublemakers. Kevin Curtis/Science Source hide caption

itoggle caption Kevin Curtis/Science Source

Anne Koller closes her eyes as an oncology nurse attaches a line for chemotherapy to a port in her chest. Koller typically spends three to six hours getting each treatment. Sarah Jane Tribble/WCPN hide caption

itoggle caption Sarah Jane Tribble/WCPN

The blood cancer in soft-shell clams poses no risk to humans, but it does kill the shellfish. Pat Wellenbach/AP hide caption

itoggle caption Pat Wellenbach/AP

Blaze Bioscience is commercially developing the "paint," which glows when exposed to near-infrared light. Courtesy of Blaze Bioscience hide caption

itoggle caption Courtesy of Blaze Bioscience

Melinda Townsend-Breslin holds a photo showing her and her mother standing in the parking lot of a favorite thrift store in 2013. William DeShazer for NPR hide caption

itoggle caption William DeShazer for NPR

MaryAnn Anselmo has started to sing again after recovering from brain surgery and having successful treatment with a drug that targeted a mutation in her tumor cells. Dave Gershgorn/WNYC hide caption

itoggle caption Dave Gershgorn/WNYC

The Josephson family in 2001, after Dixie (third from left) was told she had cancer. Courtesy of the Josephsons hide caption

itoggle caption Courtesy of the Josephsons

Central Illinois corn farmer Jerry McCulley refills his sprayer with the weedkiller glyphosate on a farm near Auburn, Ill. A new assessment of the chemical finds that the (uncertain) risks mainly affect the people who work with it or who come in direct contact with areas where it's applied. Seth Perlman/AP hide caption

itoggle caption Seth Perlman/AP

Actress and filmmaker Angelina Jolie Pitt says she had her ovaries and fallopian tubes removed to lower her odds of getting cancer. Matt Sayles/Matt Sayles/Invision/AP hide caption

itoggle caption Matt Sayles/Matt Sayles/Invision/AP

Both James Eversull (left) and Pat Patchell were treated with experimental chemotherapy and radiation for leukemia as children in the 1960s. Together, they're now some of the country's oldest leukemia survivors.. Courtesy of James Eversull; Courtesy of Pat Patchell hide caption

itoggle caption Courtesy of James Eversull; Courtesy of Pat Patchell