To assess trends in cancer, we evaluated the risk of one generation compared to that 25 years earlier (generational risk) for three groupings of cancers: those for which a substantial proportion is related to tobacco; those reflecting advances in screening or treatment; and a residual category of all other cancers.
In persons 20-84 years of age, we used age-period-cohort models to summarize time trends in terms of generational risk and average annual percent change for U.S. cancer incidence (1975-2004) and mortality (1970-2004) rates associated with these three cancer groupings.
Adult white men today developed 16% fewer tobacco-related cancers and had 21% fewer deaths due to those cancers than their fathers’ generation, while adult white women experienced increases of 28% and 19%, respectively, relative to their mothers. Incidence of commonly screened cancers rose 74% in men and 10% in women, while mortality fell 25% in men and 31% in women. For cancers not known to be chiefly linked to tobacco or screening, incidence was 34% and 23% higher in white men and women, respectively, than in their parents’ generation 25 years earlier. Mortality in this residual category decreased 14% in men and 18% in women. Results among blacks were qualitatively similar to those among whites.
Despite declining overall cancer death rates, adults are experiencing increased incidence of cancer not associated with tobacco or screening relative to their parents. Future research should examine whether similar patterns are exhibited in other modern nations and should identify population-wide avoidable risks that could account for unexplained increases in these residual cancers.
Keywords: Generational risk, Cancer trends, SEER, Age-Period-Cohort model, Cancer incidence, Cancer mortality, Tobacco, Screening, Occupational cancer, Environmental cancer