That cancer mortality is declining at a time in which the aged segment of the population is growing, and ever more people are overweight and obese, is a testament to (a) improved prevention (largely fewer people smoking, which has a sizable impact on lung cancer incidence and severity) and (b) the ever increasing efficacy of modern cancer treatments, particularly immunotherapies. These newer cancer therapies are still in the comparatively early stages of evolution as a technology platform, and we should expect these gains to continue. The immunotherapies of the 2030s will be very impressive in comparison to those deployed today.
The cancer death rate declined by 29% from 1991 to 2017, including a 2.2% drop from 2016 to 2017, the largest single-year drop in cancer mortality ever reported. The steady 26-year decline in overall cancer mortality is driven by long-term drops in death rates for the four major cancers - lung, colorectal, breast, and prostate, although recent trends are mixed. The pace of mortality reductions for lung cancer - the leading cause of cancer death - accelerated in recent years.
Overall cancer death rates dropped by an average of 1.5% per year during the most recent decade of data (2008-2017), continuing a trend that began in the early 1990s and resulting in the 29% drop in cancer mortality in that time. The drop translates to approximately 2.9 million fewer cancer deaths than would have occurred had mortality rates remained at their peak. Continuing declines in cancer mortality contrast with a stable trend for all other causes of death combined, reflecting a slowing decline for heart disease, stabilizing rates for cerebrovascular disease, and an increasing trend for accidents and Alzheimer's disease.
Lung cancer death rates have dropped by 51% (since 1990) in men and by 26% (since 2002) in women, with the most rapid progress in recent years. For example, reductions in mortality accelerated from 3% per year during 2008-2013 to 5% per year during 2013-2017 in men and from 2% to almost 4% in women. However, lung cancer still accounts for almost one-quarter of all cancer deaths, more than breast, prostate, and colorectal cancers combined.
The most rapid declines in mortality occurred for melanoma of the skin, on the heels of breakthrough treatments approved in 2011 that pushed one-year survival for patients diagnosed with metastatic disease from 42% during 2008-2010 to 55% during 2013-2015. This progress is likewise reflected in the overall melanoma death rate, which dropped by 7% per year during 2013-2017 in people ages 20 to 64, compared to declines during 2006-2010 (prior to FDA approval of ipilimumab and vemurafenib) of 2%-3% per year in those ages 20 to 49 and 1% per year in those ages 50 to 64. Even more striking are the mortality declines of 5% to 6% in individuals 65 and older, among whom rates were previously increasing.