Differential time series analysis shows deceleration in melanoma mortality prior to the widespread use of highly effective therapies

Abstract

Although the recent drop in melanoma mortality has been attributed to the introduction of newer therapies, the impact of ongoing public efforts remains unknown. Characterize and model melanoma mortality trends before the era of molecular and immune therapies (1969-2014) in the U.S. and Australia. Differential time series analysis based on population-ascertained melanoma mortality rates from the U.S. and Australia. Mortality rates were modeled and compared to the trajectories of ten other cancers. Melanoma mortality rates have been significantly decelerating since the 1970s in both the U.S. (P<.0001) and Australia (P=.0021). Zero acceleration occurred around 2001 (95% CI: 1996, 2008) for the U.S. and 2004 (95% CI: 1999, 2011) for Australia. Male mortality rates decelerated 3x-4x faster than females in both countries. Melanoma mortality followed a similar quadratic function (R2>0.9) to 10 other cancers, albeit with a later inflection point (1986 vs 2001) and broader focal width. Absolute mortality data used without further stratification or considering cancer incidence or covariates. Melanoma deaths have been decelerating for the past 5decades, reaching an inflection point around 2001, suggesting that mitigating campaigns were already afoot in both the U.S. and Australia before the advent of modern therapies.