Breast Cancer Facts and Figures
Incidence
- In 2004 breast cancer was the most common cancer in women, excepting non melanoma skin cancer. It accounted for 27% of all new female cancer cases.
- In 2004 the Age Standardized Incidence Rate (ASIR) was 96 per 100,000 women.
- Breast cancer is rarely diagnosed in people younger than 40. Incidence rises steeply thereafter, peaking in women aged 75-79 years. Most cases (80%) occur in women over 50 years of age.
Age standardized incidence rates female breast cancer, Canada, 1972-2004
Text Equivalent - Figure: Age standardized incidence rates female breast cancer, Canada, 1972-2004
Figure: Age standardized incidence rates female breast cancer, Canada, 1972-2004
Line chart showing age-standardized rates 1972 to 2004. Rates are age-standardized to the 1991 Canadian population.
1972= 81.15; 1973= 82.20; 1974= 88.27; 1975= 85.14; 1976= 84.63; 1977= 84.41; 1978= 86.06; 1979= 87.28; 1980= 83.26; 1981= 86.54; 1982= 86.01; 1983= 89.25; 1984= 90.34; 1985= 92.16; 1986= 88.61; 1987= 91.09; 1988= 97.81; 1989= 96.40; 1990= 95.98; 1991= 100.18; 1992= 102.15; 1993= 99.31; 1994= 99.26; 1995= 99.05; 1996= 98.98; 1997= 102.51; 1998= 103.56; 1999= 105.62; 2000= 101.90; 2001= 100.54; 2002= 102.48; 2003= 97.00; 2004= 97.37;
- The ASIR for female breast cancer increased significantly between 1972 and 1999 (approximately 0.9% per year but has been declining since 2000 (approximately 1.6% per year).
- The ASIRs have remained steady over time for women under 50 years of age. In contrast, women aged 50 years and over had an increasing ASIR until the late 1990s.
Mortality
- Female breast cancer is the second most common cause of cancer death in women in Canada, accounting for 15% of all cancer deaths.
- Mortality rates from female breast cancer have fallen by 25% from 31.4 per 100,000 women in 1972 to 23.1 per 100,000 women in 2004 (decreasing on average 0.7 % per year). These decreases are due to screening and improved treatment.
Survival
- The five-year relative survival rate from female breast cancer has increased over the last 10 years to approximately 83%.
- The observed increase in relative survival in women aged 50 to 69 years (the age group that is the primary focus of breast screening programs) is greater than in any other age group, suggesting a screening effect.
* Data source is from the Canadian Cancer Registry Database (Orius system)