Breast cancer is a very real risk for women — it is estimated that 26,300 Canadian women will be diagnosed with breast cancer this year and 5,000 will die — but there are a lot of myths put forth about what causes it.
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With breast cancer awareness month just days from kicking off, we’ve pulled some of the most common breast cancer myths and spoke to experts to determine their veracity.
Wearing a bra with underwire will increase cancer risk
The going philosophy on bras and breast cancer is that the underwire blocks the lymph fluid from draining out to the rest of the body and being naturally expunged, thus allowing toxins to pool in the breast.
“At this time, there is no reliable, scientific evidence that shows a link between wearing a bra and developing breast cancer,” Flynn says.
Dr. David Warr, medical oncologist lead in the breast cancer program at Princess Margaret Cancer Centre, calls the evidence presented in the one study that found a causal link “weak,” and BreastCancer.org says there was “no real difference” in risk between women who wore a bra and those who didn’t.
The larger your breasts, the higher your chance of developing cancer
“There is evidence in post-menopausal women that larger cup size is associated with a slightly higher incidence of breast cancer. However, this may not be cause and effect,” Warr says. “Obese women tend to have larger breasts and are less likely to go braless. Obesity, in turn, is associated with breast cancer but it isn’t the bra that is the likely culprit but the obesity.”
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A 2012 study published in the journal BMC Medical Genetics claimed to have found a link between larger breast size and increased cancer risk, but experts caution that the research was largely misrepresented by the press. What the study found was that certain genes associated with breast size are also associated with breast cancer, but it did not prove that the “genetic variations translate into increased rates of the condition among women with large breasts.”
Caffeine increases breast cancer risk
This is plain untrue.
Antiperspirant causes breast cancer
Despite the fact that natural health practitioners have been vilifying antiperspirant for decades, medical health experts have consistently maintained that there is no proven link between antiperspirant and cancer.
“Antiperspirants do stop perspiration, but the main purpose of perspiration is to cool the body — not to get rid of toxins,” the Canadian Cancer Society states on its website. “Lymph nodes in the armpits do clear some toxins from the body, but your liver and kidneys are more important for clearing substances from your system, and far more toxins are removed by your kidneys and liver than through perspiration.”
A breast injury can cause breast cancer
Warr points out that typically this conclusion is reached by patients who experience some kind of breast trauma (like a seat belt injury or fall) months before a lump is discovered. But this isn’t possible.
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The correlation between an injury and cancer detection is more likely due to a doctor discovering underlying cancer in the course of treating the injury.
Men don’t get breast cancer
Although it’s not very common — 0.9 per cent of breast cancer cases occur in men, and they make up 0.2 per cent of all cancers in men — men can develop breast cancer.
“It is true that breast cancer is very uncommon in men, but they do account for a small percentage of patients seen in the breast clinic. New lumps should not be ignored,” Warr says.
A lump means you have cancer
This is a tricky one to navigate because women have been consistently told that lumps are a sign that something is amiss. But cancer should not be a foregone conclusion.
“Only a small percentage of breast lumps turn out to be cancer,” Flynn says. “If you discover a persistent lump in your breast or notice any changes in breast tissue, it should never be ignored. It is very important to see your doctor.”
What are signs to look out for?
According to the Canadian Cancer Society, the most common sign is ductal carcinoma, a hard lump that doesn’t feel like the rest of your breast tissue — it can feel like it’s attached to your skin, it doesn’t get bigger or smaller with your period, and it’s not painful. Lobular carcinoma, on the other hand, does not form a lump and feels like the breast tissue is getting thicker or harder.
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Other symptoms include:
- A lump in the armpit (called the axilla)
- Changes in the shape or size of the breast
- Changes to the nipple, such as a nipple that suddenly starts to point inward (called an inverted nipple)
- Discharge that comes out of the nipple without squeezing it or that has blood in it
“Breast cancer may not cause any signs or symptoms in its early stages,” Flynn points out. “Screening tests, such as a mammogram, help find breast cancer before any symptoms develop.”
In Canada, it is advised that women aged 50 to 69 have a mammogram every two years.
For more myth-busting facts about breast cancer, visit Rethink Breast Cancer’s new #8008135 campaign.
LISTEN: Marilisa Racco joins Angela on News Talk 770 to describe her findings