It will be difficult to shift the breast-screening age,
even if the science does not support screening women under 50,
Dunedin breast cancer survivor Dr Sue Walthert says.
Dr Walthert fears a change to the age threshold could shake
women's confidence in breast-screening generally.
Debate was ignited last week by University of Otago
Wellington academics Dr Caroline Shaw and Associate Prof
Diana Sarfati, who have written public health blog posts
saying the benefit of breast cancer screening is much less
than previously thought, because of cancer over-detection and
New Zealand starts breast-screening at 45, earlier than
Australia, Canada, or the United Kingdom.
Screening could detect cancers that would never cause a
problem in a person's lifetime, the blog said.
''The problem is that when we identify a breast cancer
through screening we can't always tell if it is a cancer that
is going to cause a problem or not. So we have to treat them
Treatments, such as radiotherapy, could be ''mutilating,
painful and involve long-term side effects'', the blog said.
Substantial advances had been made in breast cancer treatment
since randomised control trials (RCTs) of screening in the
1970s and early 1980s and, consequently, survival and
mortality had improved considerably.
''The balance of benefits and harms in this age group is not
favourable. In New Zealand, we need to stop screening women
under 50 and start being more honest about the lack of
clarity about the evidence for screening in older women,'' Dr
Shaw and Prof Sarfati said.
Dr Walthert, who developed a cancer survivorship programme
for the Otago-Southland division of the Cancer Society after
her own experience of breast cancer, said screening
programmes always involved some over-diagnosis and
under-diagnosis. It was difficult because science was
''The screening programme should make its decisions based on
the science but ... the science does not know 100%. It can
only say on balance what the best thing to recommend is.''
Women in that age group needed to be able to make the
decision on screening themselves, after hearing the pros and
''I think it will be hard for NZ to change back to age 50 for
breast-screening, even if the science tells us this is the
best thing to do.
''I would worry that women would be made to feel uneasy about
screening in general.''
If the age was changed, it would need to be accompanied by a
strong education programme.
''Women need to be empowered through understanding science in
simple terms and there are some excellent brains in NZ
capable of helping the health department with that task.''
University of Otago screening authority Associate Prof Brian
Cox said the resources used to screen women under 50 would be
better used for other services.
The lack of evidence for the benefits of screening this age
group had been evident for more than 20 years.
He believed there were financial agendas at play keeping the
age at 45, but said cost pressures in health increasingly
meant funded services had to be effective.
Even the United States had shifted the age at which testing
started in response to the scientific evidence, Prof Cox
Breast Cancer Foundation chief executive Evangelia Henderson
strongly disagreed with the call to lift the age and said
breast cancer detections in women under 50 had saved hundreds
''In 2012, we had 423 women aged between 45 and 49 diagnosed
in New Zealand with breast cancer, and that's invasive breast
cancer we're talking about.''
BreastScreen Aotearoa clinical leader Dr Marli Gregory told
the Otago Daily Times there was no plan to review the
The Ministry of Health's National Screening Unit regularly
monitored international literature and other international
screening programmes, she said.
''In New Zealand, there has been a steady reduction in breast
cancer mortality rates since 1990,'' Dr Gregory said.
The breast-screening authority had commissioned a mortality
study to assess the breast screening programme. Results would
be available next year.
Additional reporting by APNZ.