The common breast cancer myth that might be putting women at risk

Every day, about 58 Australians will be diagnosed with breast cancer. But despite it being the most common cancer among women, some myths are hard to shake.

New consumer research from the National Breast Cancer Foundation (NBCF) suggests many still associate breast size with risk.

In the small survey of 340 Australians, almost one in four respondents said their breast size influences how confident they feel discussing breast cancer risk and changes. Nearly one in five incorrectly believed breast size influenced their risk of breast cancer.

When Narelle Nalbantof, now approaching her 60s, was diagnosed with breast cancer (ductal carcinoma in situ) in 2011, it came as a shock.

“I was going to a breast screening with a friend of mine whose mother and grandmother had passed away from breast cancer, so she needed to get her annual checkup and I started going with her just to ensure that she got them and to make a day of it,” she says.

“I have no family history of breast cancer and also, I have smallish breasts, and she had very large breasts.”

Dr Cleola Anderiesz, chief executive of the National Breast Cancer Foundation, says the findings “highlight how misconceptions about breast size continue to influence women’s confidence, but also understanding of their own personal risk”.

Anderiesz says other myths concerning breast cancer include the belief that wearing underwire bras or using deodorant increases risk.

“Breast cancer is an extraordinarily complex disease, and it’s made up of multiple different subtypes, and so understanding then of risk can vary enormously, and be shaped by myths, oversimplifications or outdated ideas rather than evidence,” she says.

Professor Nehmat Houssami, public health physician and breast physician at the University of Sydney, understands why people may associate breast size with cancer risk.

However, she emphasises “there is no clear or consistent evidence that [breast size] is independently a risk factor for breast cancer”.

“But there may be another a confounding factor, such as if we’re carrying a lot of weight, it’s possible that breast size might be larger, and we know that adult obesity increases the risk of breast cancer,” she says.

People with dense breasts are also at greater risk of developing breast cancer, which is believed to be because they have more glandular tissue in which cancer can form. Having denser breasts is not associated with size.

Dense tissue can appear white on mammograms, making it difficult for radiologists to detect cancer, though use of artificial intelligence may help overcome this.

Houssami says the focus on breast density and its effect in reducing mammogram inaccuracy in recent years has been important. However, she wants to see more attention paid to other known cancer risk factors.

“There are many other risk factors for breast cancer, some we can’t change,” she says. These include earlier onset of puberty, later menopause, and whether a woman has had children and breastfed.

There are “two big ones that we can realistically do something about”. These are high body fat in adult life, which increases the risk of a woman experiencing postmenopausal breast cancer, and alcohol.

“Even if a woman has just one drink a day, most days of the week, compared to women who never drink, alcohol is a significant independent risk factor for developing breast cancer.”

Importantly, Houssami says, there is no single risk factor for breast cancer, and “many women who don’t have risk factors for breast cancer develop it, so it can also occur by chance”.

On the other hand, “it’s important for women to understand that having a risk factor doesn’t mean you will get breast cancer, and there’s usually a complex interplay of risk factors that can predispose a woman to breast cancer”.

Professor Tracey O’Brien, NSW chief cancer officer and chief executive of Cancer Institute NSW, says the NBCF findings highlight the importance of regular screening and early detection. Women with large breasts can also report extra discomfort during screenings, which could make them hesitant to schedule appointments.

“Every woman should know their breasts, and if they notice any changes, lumps, discharge or have any concerns, then they should absolutely see their GP. And if they’re concerned about their individual risk, if there’s a family history, then they should see their GP and find out if they need more personalised screening,” she says.

In Australia, women over the age of 40 can have a free mammogram every two years.

Nalbantof, who underwent a partial mastectomy on one breast followed by a full removal, says the experience has taken an immense physical and psychological toll.

Even the reconstruction she had on the affected breast was more taxing than she anticipated.

“It’s the mental anguish and the mutilation of your body. First of all, you need to be confident that you are not going to die from it [cancer], that you will be a survivor. And then once you put it behind you, you just don’t want to go back there,” she says, referring to the reconstruction.

Today, Nalbantof, who lives in the Hunter region, is a fierce advocate for breast cancer awareness, and enjoys daily swims, dragon boat racing and dancing.

She’s recently gotten a tattoo to mark her battle with cancer, which features a tree of life and animal imagery to symbolise her children and grandchildren.

“For years and years, everyone said, ‘Oh, you’re going to get a nipple tattooed over the scarring’ and I always said, ‘No, I’ve already got a nipple on the other side. If I get any tattooing, it’s going to be a kick-ass tattoo,’ ” she says.

“I’ve loved it so much and loved looking in the mirror at the tattooing instead of the scarring.”

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