Temporal trends in breast cancer survival in Sweden: significant improvement in 20 years.

Of all women with a newly diagnosed breast cancer diagnosed in 1960-78 in Sweden, 57,068 (98%) were included in a complete follow-up during 1-19 years of observation. The 5-year mortality attributable to breast cancer was reduced by 29% from the period 1960-64 to 1975-78, which corresponded to an increase in relative survival by 10.5% (95% confidence limits, 7.2 and 13.8). There was a highly significant and regular trend during the study period toward a decrease in the annual hazard rate; this was confined to the first 4-5 years after diagnosis. The temporal trend toward improved survival was apparent in all age groups, but it was of lower magnitude among women younger than 45 years old.