THE AMERICAN CANCER SOCIETY reported the largest-ever one-year decline in the rate of U.S. deaths from cancer. The rate has fallen by about 1.5 percent a year since 1991, but that accelerated to 2.5 percent between 2016 and 2017. Rebecca Siegel, the lead author of the report, said that’s the largest drop since 1930. Siegel said advances in lung cancer treatments drove most of the decline. Smoking has also been on the decline for decades.