Generational risks for cancers not related to tobacco, screening, or treatment in the United States.

BACKGROUND: To assess trends in cancer, the authors evaluated the risk of 1 generation compared with that 25 years earlier (generational risk) for 3 groupings of cancers: those related to tobacco; those that reflect advances in screening or treatment; and a residual category of all other cancers.
METHODS: In individuals ages 20 years to 84 years, age-period-cohort models were used to summarize time trends in terms of generational risk and average annual percentage change for US cancer incidence (1975-2004) and mortality (1970-2004) rates associated with these 3 cancer groupings.
RESULTS: Adult white men today developed 16% fewer tobacco-related cancers and had 21% fewer deaths because of those cancers than their fathers' generation, whereas adult white women experienced increases of 28% and 19%, respectively, relative to their mothers. The incidence of commonly screened cancers rose 74% in men and 10% in women, whereas mortality fell 25% in men and 31% in women. For cancers that have not been linked chiefly to tobacco or screening, the incidence was 34% and 23% higher in white men and white 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.
CONCLUSIONS: Despite declining overall cancer death rates, adults are experiencing increased incidence of cancers that are 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.