Since 1991, the cancer death rate has dropped by 26%, according to the latest data from the American Cancer Society (ACS). That decline represents nearly 2.4 million lives saved from cancer.
The decreasing death rate continues a downward trend in mortality from the disease, which ACS experts say is due to a combination of factors. One of the biggest forces behind the decline is a reduction in smoking, thanks to public health campaigns warning of its dangers, and tobacco taxes that discourage people from picking up the habit. While lung cancer remains a leading cause of cancer death, death rates have dropped by 45% among men from 1990 to 2015 and by 19% among women from 2002 to 2015.
Other prevention strategies—including screening tests, such as mammograms for breast cancer, blood tests for prostate cancer and colonoscopy for colon cancer—also contribute to lower death rates. Advances in treatment have also played a big role in bringing new diagnoses of cancer down, as well as reducing deaths from the disease.
But lately, studies have questioned the effectiveness of two major screening methods: the mammogram for detecting breast cancer and the blood-based prostate specific antigen (PSA) test for prostate cancer. Some studies failed to show that these screening tests were associated with a reduction in deaths from those cancers; at the same time, they led to an increase in false positive results that require additional testing that can put women at risk of complications and anxiety about their health.
The data led the U.S. Preventive Services Task Force, an independent group of experts convened by the government, to revise recommendations about mammography and PSA testing. For mammography, the task force recommends that women start screening for breast cancer at age 50 instead of 40, and that they get the test every other year. On the PSA, in 2012 the group initially advised men to skip the test entirely if they did not have risk factors for prostate cancer, but in 2017 recommended that men discuss with their doctors whether and when they should get the PSA test.
Ahmedin Jemal, vice president of surveillance and health service research at ACS and the senior author of the report, says that screening methods do need to get better. “In the future, we need to figure out how to make screening tests more perfect by detecting cancers or lesions that if left unchecked or undetected, would grow and advance and become lethal,” he says.
Access to screening as well as treatment also remains important, he says. The report found that while cancer deaths continue to drop, they remain higher among people with low incomes and among African-Americans. Death rates were 14% higher among blacks than among whites in 2015.