The word “risk” gets thrown around a lot these days. And that’s actually a great thing, particularly when it comes to breast cancer. By knowing your risk of breast cancer, and what factors make up that risk, you can make better informed decisions not only about your breast health but how you choose to mentally and emotionally deal with the issues of breast health and breast cancer.
In technical – and very dry – terms, the risk of a disease is the chance of getting that disease over a certain period of time. The most common timeframes used to describe risk are 10-year increments and something called “lifetime risk” – the chance of ever developing the disease as an adult.
When it comes to breast cancer, lifetime risk is the one most women would recognize by the ratio “one in eight.” “One in eight” describes an average American woman’s lifetime risk of ever developing breast cancer, meaning that out of every 8 women, 1 will develop the disease. This translates to about a 12 percent chance of being diagnosed with breast cancer from age 18 until about age 85.
Compared to many other health risks, this is a pretty high percentage, but certainly not the highest for a major disease. The lifetime risk of heart disease, say, is about 50 percent.
Not surprisingly, looking at breast cancer risk in shorter 10-year segments can make things look less daunting – and in some ways provides a better sense of actual risk. Because diseases like cancer and heart disease are more common as women age – and to be blunt, because everyone eventually dies of something – lifetime risks can easily inflate the perception that a disease is more threatening than it actually is. This is because so much of the risk accumulates very late in life.
For some perspective, let’s look at the risks of breast cancer across a couple ten-year age groups: the average woman’s risk of developing breast cancer from age 40 to age 50 is 1.5 percent, and from age 60 to 70 is 3.5 percent (1). This means that out of a 100 forty year old women, 1.5 would develop breast cancer by the time they turned 50. Likewise, out of 100 fifty year old women, 3.5 would develop breast cancer by the time they turned 60. (Of course, these are statistical “people” since you can’t have half a person.).
As expected, these 10-year risks are much smaller than the average lifetime risk of 12 percent. Though they still show breast cancer to be a prominent disease – these risks are about three times higher than those of colon cancer for the same age groups – they also show that breast cancer is not as imminent a threat as many women fear. It’s not uncommon for younger women to overestimate their risk of dying from the disease over the next 10 years by up to 20 times (2).
Many factors determine a woman’s risk of breast cancer, including things she has control over, like exercise and diet, and things she has little or no control over, like genetics and family history. Focusing efforts on those factors that can be changed for the better can lower the risk of breast cancer.
In other words, it can help prevent it.
An Ounce (or More) of Prevention
Prevention has become a real buzzword of late, and that makes many a health professional jump for joy. Why? Well, let’s look at the classic “river story” parable, which we’ll paraphrase.
A woman was walking on a riverbank and saw someone floating down the river yelling for help. The woman picked up a large tree branch and fished the person out. No sooner did she do that then another person came floating down. She fished that person out. Then another and another and another came down. She asked others to help rescue the people. And they did. Still, more and more came floating down, and the helpers were soon overwhelmed, realizing they couldn’t help everyone.
The woman decided to quickly run up-river to see why so many people were falling in. On a popular bridge over the river, she found a large, obscured hole that people were falling through. She patched it, and people no longer fell into the river through the hole.
This story perfectly illustrates the power of prevention. By working to stop problems early on, you can help avoid bigger, harder issues later on. We’ll never be able to stop all the people from falling into the river. But repairing as many holes as we’re able to can help cut way down on the number of people who fall in and need heroic rescue downstream.
It’s the same way with diseases like cancer and heart disease. A healthy lifestyle can cut down on the number of people who develop a disease. And although we’ll likely never be able to stop 100 percent of cancers or heart attacks, prevention still offers the most realistic, efficient, and effective way of tackling the burden of chronic diseases the world over.
1. Howlader N, Noone AM, Krapcho M, Garshell J, Neyman N, Altekruse SF, Kosary CL, Yu M, Ruhl J, Tatalovich Z, Cho H, Mariotto A, Lewis DR, Chen HS, Feuer EJ, C. KA. (National Cancer Institute, Bethesda, MD, 2013).
2. W. C. Black, R. F. Nease, Jr., A. N. Tosteson, Perceptions of breast cancer risk and screening effectiveness in women younger than 50 years of age. J Natl Cancer Inst 87, 720-731 (1995); published online EpubMay 17