SHIMKIN1 has commented on the nearly stable levels of the death rate, the incidence rate, and the survival rate for cancer of the breast in the United States in recent decades. The statistics he used were all total rates, adjusted for changes in the age distribution of the population, and he made no reference to trends in the rates for specific age groups. He infers from the stability of these ageadjusted total rates that etiologic, diagnostic, and therapeutic factors have remained either stationary or in a state of balance. As an example, he believes that the stable rates are evidence against important etiologic roles for nonlactation or for use of exogenous estrogens, since it is believed that these factors have exhibited upward or downward trends.
We have recently examined the trend of the age-color-specific death rates from cancer of the breast in the United States,2 and these suggest
Kraus AS, Oppenheim A. Trend of Mortality From Cancer of the Breast. JAMA. 1965;194(1):89–90. doi:10.1001/jama.1965.03090140097030