Busting breast cancer myths

Underwire bras, antiperspirants, big boobs and breastfeeding cause breast cancer. True or false? False. But the existence of these urban myths about breast cancer at least means women are talking about the disease.

Associate professor John Boyages, director of the NSW Breast Cancer Institute and spokesman for Australia's National Breast Cancer Foundation, says 13,000 women are diagnosed with the disease in each year, which means there is a high level of awareness.

Professor Michael Henderson, from Melbourne's Peter MacCallum Cancer Centre, says: "Our mothers will tell you that in the 1940s, '50s and '60s, if a woman had breast cancer, the last thing she did was tell anyone."

The National Breast and Ovarian Cancer Centre says to be sceptical of information "not from recognised medical and scientific experts". Here we dispel some of the myths.

MYTH ONE

Having a family history of breast cancer means you will get the disease

Most women who get breast cancer don't have a family history of the disease, Boyages says. "Therefore, all women should think about their breast health," he says. "For women aged 50-69, that means going for regular mammograms."

MYTH TWO

Breast cancer is a young woman's disease

With the public face of breast cancer featuring the young faces of Belinda Emmett, Jane McGrath, Kylie Minogue and Christina Applegate, you could be forgiven for thinking it's a young woman's disease. It's not.

"The data is quite strong," Henderson says. "In Australia we are not seeing an increase in young women [under 50] with breast cancer. The [most common] age is the late 50s and 60s."

MYTH THREE

Antiperspirants and underwire bras cause breast cancer

"These are urban myths that have been debunked many times," Henderson says. Boyages says: "Breast cancer has been around since the ancient Egyptians and I don't think they had underwire bras."

MYTH FOUR

Freezing water in plastic, or microwave cooking with plastics releases cancer-causing toxins

One email doing the rounds warns of the dangers of the above and is attributed to the John Hopkins Sidney Kimmel Comprehensive Cancer Centre in Baltimore. John Hopkins has labelled the email a hoax.

"Freezing water does not cause the release of chemicals from plastic bottles," Boyages says. "And there are clear recommendations to only use microwave-safe containers. "

MYTH FIVE

Lumpy breasts increase your risk

Boyages says: "A lot of women get lumpier breasts before their period or may have cysts, which are common in the breast. Nine out of 10 lumps are not cancer. But if you have a lump that doesn't go away, have a triple test."

MYTH SIX

Small breasts reduce your risk

Breast size has nothing to do with the risk of breast cancer but Henderson says obese women, specifically women who are post-menopausal, have an increased risk.

MYTH SEVEN

Implants increase your risk of breast cancer

Silicon breast implants are not linked to breast cancer risk. The National Breast and Ovarian Cancer Centre reports that a large study on the long-term effects of implants followed women for more than 10 years and showed no increased risk.

Boyages says: "In some ways it's easier to find breast cancer, because the implant pushes the breast tissue forward."

MYTH EIGHT

Breast pain indicates breast cancer

Most breast cancers don't cause significant pain but a few do. "So you can't be complacent if a lump is painful," Boyages says. "In about 10 per cent of cases of breast cancer there is pain."

MYTH NINE

Nipple discharge indicates breast cancer

The majority of nipple discharge has nothing to do with cancer but Henderson says bloody discharges are a concern. "Even then, more often than not, it is not breast cancer," he says. Boyages says doctors will also be concerned by discharge that is coloured "like straw".

MYTH TEN

Mammograms cause breast cancer

Exposure to ionising radiation can cause cancer. However, given the limited number of mammograms a woman has in her lifetime and the standards of mammographic equipment in use in Australia, the increased radiation exposure from a mammogram is minimal, says the NBOCC.

"If you are 50 [and] having a mammogram every two years, the risk of radiation is far less than other risks we take every day," Boyages says.

However, having radiation for other cancers does increase your risk of breast cancer.

"If, for example, someone had Hodgkin's lymphoma as a teenager and had radiation treatment, they would be at much higher risk of breast cancer, so should start having mammograms 10 years after their initial treatment," Boyages says.

How to improve your breast health

See your doctor regularly

"If you have a lump, get it checked out with the triple test," Boyages says. "Make sure the GP follows the national guidelines for breast checks."

Be breast aware

Be aware of changes in your breasts and find out what your normal pattern is. "Perhaps your breasts are lumpy before you get your period," Boyages says. "If so, do the breast self-examination after your period."

Participate in national breast screening

This should be done once you turn 50, Henderson says, adding that "women aged 40-50, after discussion with their doctor, may consider screening at an earlier stage".

Maintain a healthy lifestyle

It's estimated that one-quarter of breast cancers are attributable to our lifestyle - particularly obesity, diet and lack of exercise - says Henderson. "Once you've had breast cancer, a moderate amount of exercise, getting weight down and reducing the fat in your diet may help to reduce the risk of breast cancer coming back," he says.

Drink in moderation

People who drink alcohol to excess may have a slightly higher risk of breast cancer. Moderation is the key.

Have good vitamin D levels

"There's some evidence that low vitamin D levels can increase the risk of breast cancer," Boyages says.

- © Fairfax NZ News