New research: 90% of older NZ women underestimate their breast cancer risk
April 10, 2014
Perception of being “past breast cancer” plus high costs deter women from ongoing screening – NZBCF asks mammogram clinics to cut prices
New research commissioned by the NZ Breast Cancer Foundation reveals that older women mistakenly believe their breast cancer risk is lower in their seventies, when they no longer qualify for free mammograms, than it was in their fifties. Thinking they’re “past breast cancer”, and put off by having to pay for mammograms, most women don’t plan to continue screening.
In reality, Ministry of Health statistics show the breast cancer risk for a woman in her seventies today is slightly higher than it was back when she started screening, and it continues to increase as she ages.
The NZBCF research, undertaken by Colmar Brunton, shows that only 10% of women realise their risk is higher in old age, while 40% assume it is lower.
“Women do tell us they thought they were ‘past breast cancer’ when their free mammograms stopped, but we were surprised just how few are aware that their risk goes up as they age,” said NZBCF chief executive (Mrs) Van Henderson. “Our message to New Zealand women is, keep an eye on your breasts and, if you’re in good health, continue with mammograms in your seventies.”
Historically, arguments against screening older women have been based on the assumption that other medical conditions are more likely than breast cancer to cause death. But a New Zealand woman aged 70 in 2014 is likely to live to 89, twenty years after her last free mammogram, and people increasingly expect to stay fit and active for longer. 70% of the women surveyed by Colmar Brunton rated their health as good or excellent.
The women surveyed were well aware of the need for mammograms in their younger years – 72% had previously participated in the BreastScreen Aotearoa programme, matching the current population-wide screening uptake. But only one third had had a mammogram in the past two years. Most of those were in the 70-74 age bracket, and their mammograms were predominantly free, indicating they took place when the women were still covered by the screening programme.
The most common reason for women not having a recent mammogram was “At my age, I didn’t think I need to” (46%), followed by “No family history of breast cancer” (18%). In reality, only 5-10% of breast cancers are related to family history.
Cost is a problem, women say; NZBCF to ask clinics to drop their prices
Cost was also an issue for women in deciding whether or not to continue with mammograms. 40% of women had no plans to have a mammogram in the next two years – but 80% of women aged 70-74 said they would have a free mammogram if it was offered (with the uptake dropping as women aged). Women in the North Island were much more likely to take up the offer of a free mammogram than women in the South Island. 20% of women said cost was the reason they would not have a mammogram.
Free mammogram screening was extended to age 74 in Australia in 2013. In the UK, where the Public Health Office recently launched a “Don’t assume you’re past it” campaign aimed at women over 70, a large-scale trial of breast screening to age 73 is underway.
“We would like to see the screening age extended to 74 in New Zealand,” said Belinda Scott, medical adviser to the NZBCF, “though obviously it won’t be overnight, and the BreastScreen Aotearoa programme will need to be resourced to cope with the larger volumes.”
For now, women over 70 must pay for their own mammograms, with the cost typically ranging from $145 to $195.
“That’s a lot of money for most people,” said NZBCF chief executive Van Henderson. “This week, I will be writing to every private mammogram clinic in New Zealand, asking them to offer discounted mammograms to women over 70.”
Rates of cancer spread higher for women in their 70s
The NZBCF says early detection gives women the best chance for survival, and for less invasive treatment. Although breast cancers are often slower-growing in older women, data from the Auckland Breast Cancer Register, funded by the NZBCF, shows that 16% of women diagnosed with breast cancer in their 70s end up with metastatic disease (cancer that spreads beyond the breast), compared with 11% of those diagnosed in their fifties and 10% of those diagnosed in their sixties.
“Those numbers surprised us,” Belinda Scott said. “We can’t say for certain that the number of metastatic cancers increases because women are no longer being screened, but that suspicion is there.”
A recent study of breast screening for women aged 70-74 in Australia concluded that "increased screening participation by women aged 70–74 years is associated with reduced tumour size...without a concomitant increase in cancer incidence." The study said that if mammogram participation for women aged 70-74 rose from 50% to 70%, there would be 15% fewer large cancers (larger cancers typically require more invasive surgery and have a worse prognosis).
“You sometimes hear in the media of women feeling ‘invisible’ as they age – that no one bothers with them any more,” said Van Henderson. “Well, we do bother with them, and we think their health is important. If you’re over 70, talk to your doctor about continued mammograms. And if you’re a daughter with a mum over 70, remind her that her health is important to you.”
 The research questioned 204 women aged 70-84, a sample size statistically representative of the NZ population
 88.7 years at medium death rates, based on the Statistics NZ “How long will I live?” calculator
 Breast cancer screening of women aged 70–74 years: results from a natural experiment across Australia, Breast Cancer Res Treat (2014), Nickson et al.