What do you think is the biggest risk factor for breast cancer in this 65-year old woman?

She has gained about 25 pounds since she was 18 years old.

She drinks 2 glasses of wine a day.

She is on hormone replacement therapy.

If you said hormone replacement therapy, you’d be wrong. In fact, the hormones, alcohol consumption and weight gain all increase her risk by about the same amount. But the media have positioned hormones as the worst thing women can do for their health (the biggest risk in this scenario is her age, but more on that later).

While we’re NOT promoting “hormones for all”, we think it’s important for women to know that questions are arising about the way hormones have been portrayed in the media and that women are suffering because of it.

“No one is trying to talk women into hormones, only to emphasize that when menopausal symptoms are distressing that hormone therapy is a safe option.” Robert Reid, Queen’s University, past-president of the Society of Obstetricians and Gynaecologists of Canada

The Society of Obstetricians and Gynaecologists of Canada released a statement in October of 2010 entitled “Misinformation. Misinterpretation. Missed opportunity.

Distressed symptomatic menopausal women are being denied, or are choosing to avoid, hormone therapy because of recent and misleading media coverage.”

The article discusses the landmark Women’s Health Initiative Study and how the risk of developing breast cancer has been “distorted”.

The number of deaths from breast cancer in women on the combined hormone therapy (non-human estrogens and progestins) was 2.6 deaths per 10,000 vs 1.3 deaths in women taking the placebo, a difference of 1.3 deaths per 10,000 women.

There were 8 additional cases of breast cancer among the hormone users compared to the placebo group – an increase defined as a “rare” risk by the World Health Organizaton’s standards. So how does taking hormones compare to other risks? A woman who takes hormones is as likely to get breast cancer as a woman who has 2 alcoholic beverages a day or a woman who is overweight in her postmenopausal years.

The following chart shows how a variety of factors can influence the risk of developing breast cancer:

Figure 1. Risk Factors for Breast Cancer

 

Risk Factor	Description	Relative Risk1
Alcohol Intake	2 drinks per day vs non-drinker	1.22
Body Mass Index	80th percentile, age 55 or greater vs 20th percentile	1.2
HRT (with non-human hormones)	Current user for at least 5 yrs vs non-user	1.3
Early menarche	Younger than 12 yrs vs older than 15 yrs	1.3
Late menopause	Older than 55 yrs vs younger than 45 yrs	1.2-1.5
Total Adult Weight gain	Postmenopausal women: comparison of stable weight vs weight gained since age 18 Weight Gain 22-33 lb Weight Gain 33-44 lb Weight Gain Over 44 lb	1.2-1.4 1.3-1.8 1.5-26
Radiation exposure	Repeated fluoroscopy	1.6
Age at first childbirth	No children or 1st child after age 30 vs 1st child before age 20	1.7-1.9
Family History	-1st degree relative 50 yrs or older with postmenopausal breast cancer -1st degree relative with premenopausal breast cancer -2nd degree relative with breast cancer	1.8   3.3   1.5
Current age	65 or older vs less than 65	5.8
Germline Mutation	BRAC1 gene	15-200

 

1. Relative risk = The chance of one group developing a health outcome compared to another group. For relative risk measures, the group used as the reference is given a relative risk of 1.0.

2. Adequate folate intake seems to reduce or eliminate the risk due to alcohol consumption (Mahoney et al.)

Data Sources: Singletary (2003) and Cummings et al. (2009)

Over your lifetime (assuming you live to be 90), you have a 1 in 8 chance of developing breast cancer. The chance of developing breast cancer increases with age.

Average woman’s risk of developing breast cancer by age

Age 25 less than 1 in 1000

Age 50 1 in 63

Age 75 1 in 15

Age 90 1 in 9

But the fact is, you are still far more likely to die of heart disease than breast cancer.

Does this mean that hormones are safe for all women? Absolutely not!

Our philosophy has always been that you use hormones for the shortest period of time, at the lowest dose, for symptom relief. You use hormones ONLY for the women that are truly suffering. And you consider the risk factors at play in that woman’s situation.

REFERENCES:

Cummings SR et al. (2009) Prevention of breast cancer in postmenopausal women: approaches to estimating and reducing risk. Journal of the National Cancer Institute 101 (6): 384-398.

Kirkey, S. (2010) Menopause treatment cancer risk overblown, group says. Ottawa Citizen November 18, 2010.

Lalonde, A. (2010) Misinformation. Misinterpretation. Missed opportunity.

Society of Obstetricians and Gynaecologists of Canada. October 29, 2010 www.sogc.org

Mahoney, MC et al. (2008) Opportunities and strategies for breast cancer prevention through risk reduction. CA Cancer J Clin 58: 347-371.

Singletary, SE (2003) Rating the risk factors for breast cancer. Annals of Surgery 237: 474-82.

Statistics Canada (2007) Mortality, Summary List of Causes 2007

http://www.statcan.gc.ca/pub/84f0209x/84f0209x2007000-eng.htm