CancerCare Manitoba
 
 
 
Understanding Your Risk


AT AGE 1 YEAR RISK
30 years 1 in 6,000 women
40 years 1 in 1,200 women
50 years 1 in 550 women
60 years 1 in 400 women
70 years 1 in 300 women
80 years 1 in 250 women

Source
: Intelligent Patient Guide: Breast Cancer, All you need to know to take an active part in your treatment. Olivotto, Gelmon & Kuusk. 3rd Edition. 2001, page 20.


Breast cancer is the most common cancer diagnosed in Canadian women. The cause remains unknown but risks which increase your chances of breast cancer have been identified and will vary with each individual. Are you concerned with breast cancer? in CancerCare's Clinical Investigations Office web site, contains a list of risk factors and information about breast cancer prevention trials.

As the most common cancer diagnosed in Canadian women, breast cancer will involve over 21,000 women across Canada this year. What does this mean for an individual woman?

The often quoted statistic: 1 in 9 women will develop breast cancer can be misleading and causes many women to think their risk is higher than it actually is. This number refers to the chance a woman has of developing breast cancer over a lifetime of 90 years. Because many women do not live to 90 years where the incidence is highest, and breast cancer is more common in women over 50 years, generalizing to a lifetime risk may not be the clearest way to indicate a woman's risk. It may be clearer and more useful to look at a woman's risk in relation to her age today as indicated below:

You can see by looking at this table, that even a woman who is 80 years of age only has a 1 in 250 chance of developing breast cancer in the next year. Although this does not change her 1 in 9 lifetime risk, it is a better indicator of the woman's actual risk today.