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+ Health

donna chisholm is North & Souths editor-at-large.

Catherine Hale has had the mammogram. Shes had the partial mastectomy. Shes had a month of radiotherapy. But shes still not quite sure if shes

actually had breast cancer.What she does think indeed what thou-

sands of other women in her position cant help but think is that whatever the case, a mammogram has saved her life.

Only relatively recently, however, informa-tion is emerging of the extent to which mammograms, while undoubtedly saving the lives of many, may also harm more than a few.

Hale, 67, a retired court official from Orewa, north of Auckland, was diagnosed in Septem-ber with ductal carcinoma in situ. Its a condi-tion in which the cancer cells are contained entirely within the milk duct, but which might develop into invasive cancer if left untreated. The problem for patients like Hale is theres a reasonable chance it will never progress at all making the radiotherapy and surgery not only unhelpful, but harmful.

Despite being told any treatment might be unnecessary, Hale like nearly every woman who receives such a diagnosis wasnt going to sit around and do nothing. And although

As new information emerges about the risks of overdiagnosis and overtreatment after breast screening, health officials are rethinking the advice women should get. Donna Chisholm reports.

Testing Times

Breast Screening: Too Much, Too Soon?

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two specialists told her only a local excision was required, there was pressure from within her family to go further, with one of her daughters urging her to have a full mastec-tomy just in case.

Hale said no. It was personal. Having lost my husband to bowel cancer, lost money in a stupid financial decision youre losing your looks, youre losing everything. I thought, Im not losing that yet. The specialist oncologist agreed, saying a mas tectomy in her case would be like taking a sledgehammer to swat a fly.

She says she was reassured her treatment choices were the right ones, because of the comprehensive advice she received, espe-cially from a nurse at the specialist breast practice where she was treated. The nurse explained it was a kind of catch-22 they could be damned if they did but damned if they didnt [treat]; that it may not have been necessary for me, but it could have gone the other way.

In the public mind, the reasons for and benefits of mammography are deceptively simple: it detects breast cancers early, before they become palpable lumps, so they can then be removed and treated with one or more effective therapeutic options surgery, radiotherapy and chemotherapy. Less well known is the fact that of all the cancers detected on mammography, around 25 per cent are pre-cancerous ductal carcinomas in situ. And when that condition lets call it DCIS from now on is found on biopsy to be of low grade, theres an estimated 70 per cent chance it wont progress at all. In other words, if the woman had never had a mammogram, the DCIS wouldnt have become clinically apparent in her lifetime. If, on the other hand, its high grade, it will almost inevitably go on to invasive cancer.

Hales DCIS was of intermediate grade, so its less clear how it would have behaved. The only evidence to measure that is epide-miological and thats of little use when predicting individual outcomes. The last person to try to track the clinical progres-sion of carcinomas in situ was Professor Herb Green at National Womens Hospital, whose research from 1966 to the mid-1980s into pre-invasive CIS lesions of the cervix in patients many of whom were unaware his study included their cases ended in spectacular infamy. Some of them died.

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Intriguingly, Greens nemesis, journalist Sandra Coney who co-wrote the article The Unfortunate Experiment in Metro magazine about his work and who was made a companion of the Queens Service Order for her contribution to womens health remains staunchly opposed to mam mographic screening in well women, saying the benefits are modest and the risks of unnecessary treatment significant.

At 68, Coney has never had a mammogram despite her older sister being diagnosed with breast cancer in 1988, aged only 47, and regular invitations to do so by her GP. Its become incredibly difficult to have a rational conversation about breast-cancer screening because of the kind of emotional-ism thats built up surrounding it and I gave up the task some years ago, Coney says.

Its very difficult as a womens health advocate to say other women have got it wrong. And when Im talking about other women, Im talking about the likes of the Breast Cancer Foundation, who have had very prominent women leading the campaign to raise funds for this terrible disease.

It became incredibly difficult to pour doubt on it and you have to acknow ledge breast cancer is a very serious disease and a major cause of death. So when you start doubting the one thing thats been put up as a lifesaver, and which has all the backing of the Health Ministry and an awful lot of outspoken breast physicians and breast surgeons, its been very hard to do.

Women will still tell me how theyve been saved, how they were so lucky they had a mammogram. Ill say, Well, what did they find? and half the time they dont know. Or it will turn out to be a ductal carcinoma in situ. You cant say to somebody, Well, are you sure this double mastectomy or this mas-tectomy was really necessary? when they believe their life has been saved. Thats a pretty hard call and I have to keep my mouth buttoned in situations like that.

Coney says when well women are invited to have a medical intervention, Theres a huge ethical responsibility on the part of the person asking them. Its different from the person who has symptoms and is sick who asks the doctor to find out whats the matter with them. When public health physicians and GPs intervene in peoples lives, they should be really, really sure theyre not causing harm.

Opposite: Catherine Hale had a partial mastectomy and a month of radiotherapy, but shes still not sure if she actually had breast cancer.

A mammogram machine.

Its become incredibly difficult to have a rational conversation about breast- cancer screening because of the kind of emotionalism thats built up surrounding it.

Sandra Coney, womens health advocate.

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Before the advent of widespread screening mammography, only about two per cent to five per cent of all cancers found were DCIS. Now it makes up 30 per

cent of all cancers detected in women 45 to 49, and 20 per cent of those aged 50-plus.

American radiologist Dr Handel Reynolds, in his book The Big Squeeze released last year, puts the DCIS conundrum this way: This explosion in the number of DCIS cases has been both a cause and an effect of screening mammographys success. Rapidly increasing DCIS diagnoses swelled the ranks of women diagnosed with breast cancer. This in turn helped elevate breast cancer to epidemic status an epidemic for which more mam -mographic screening was presented as the cure. Many DCIS cases actually represent what has been termed overdiagnosis.

Most women diagnosed with DCIS will have a lumpectomy, also known as a partial mastectomy, with or without radia-tion therapy. Some will have a full mastec-tomy, while a few will even opt for a preven-tive double mastectomy, ostensibly to eliminate the chance of developing cancer in the other breast.

The renewed focus on overdiagnosis was prompted partly by a report from an expert British panel published in the Lancet at the end of October 2012, examining benefits and harms from the UK programme, which screens women aged 50-plus every three years. In New Zealand, women are screened from age 45 to 69, every two years.

The panel found that while mammo-graphy prevented 43 deaths for every 10,000 women invited for screening (not necessar-ily those actually screened), it also detected 129 cancers which would never otherwise have caused a problem.

In 2009, the influential United States Preventive Services Task Force amended its 2002 recommendation that women have mammograms every one to two years from age 40, controversially advising regular screening shouldnt start until age 50. The task force chair said the new advice was aimed at reducing the potential harm of overscreening and overdiagnosis.

The British report, and others like it, has spurred New Zealands breast-screening

programme, BreastScreen Aotearoa, to rewrite its patient information leaflets to include a section on overdiagnosis, which was not previously referred to. Those changes should be introduced later in the year.

Its also attracted attention within the National Screening Advisory Committee. Its chairman, Waikato primary care professor Ross Lawrenson, says the committee wants to discuss issues around mammography this year, including risk analysis, age of access to screening and what information women receive. Its probably true to say Breast-Screen Aotearoa has promoted the benefits [of screening] but has been relatively silent about the potential harms for individuals.

West Coaster Barbara Holland, a consumer representative on the committee and co-convenor of the Federation of Womens Health Councils, believes screening women under 50 makes little difference to the death rate from breast cancer of that age group and exposes many asymptomatic women to sig-nificant risk of unnecessary harm.

But trying to quantify the risks and benefits is an inexact science which can frustrate clinicians to exasperation. For example, esti-mates of the reduction in deaths from breast cancer for screened women aged 40 to 50 range from about two per cent to 10 per cent.

The odd individual trial has shown a bigger reduction but some havent shown any reduction at all from screening under 50, says Otago University associate professor Brian Cox, whos spent more than 20 years studying the effectiveness of screening.

Its these sorts of disparities that make the interpretation of statistics confusing, says Barbara Hochstein, a Rotorua-based radiolo-gist with a specialist interest in womens imag-ing. Were at the coalface, she says. I think epidemiology, for all the other doctors involved in this, is a study we dont have the same feeling for. The numbers change depending on interpretation and methodol-ogy. Im a scientist by training and I really do want to do evidence-based medicine. I care deeply for my women.

Hochstein says that after many years using screening mammography, she hadnt heard of overdiagnosis and overtreatment until 2005, when she attended a meeting in Melbourne. Her reaction? Disbelief, I

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suppose. Until then, she had believed all small cancers and pre-cancerous lesions would certainly progress. It was more black and white when we started. Thats our whole training 20 years of working so diligently and constantly fine-tuning to find these small cancers and believing for that woman weve altered her outcome.

Hochstein subsequently chaired a mini-symposium on overdiagnosis in Auckland as part of an Australasian Society of Breast Disease meeting in Auckland in 2010. For a lot of people in the audience it was a new concept. Though it represented a challenge to her thinking, she says, part of it made sense because we all understand some can-cers are very aggressive and some arent.

As North & South reported last year, the same concerns of overdiagnosis and overtreat-ment have also been raised by those who oppose a push

by prostate cancer screening proponents to encourage men to have PSA (prostate- specific antigen) tests. However, unneces-sary treatment for prostate cancer can be far more debilitating men can be left impo-tent or incontinent and the reduction in mortality is far less. Its estimated that zero to one prostate cancer death is prevented for every 1000 men screened, while one death from breast cancer is prevented for every 180 women screened.

Its generally agreed that screening in

screening women under 50 makes little difference to the death rate from breast cancer of that age group and exposes many asymptomatic women to significant risk of harm. At 68, Sandra Coney has never had a mammogram despite her sister being diagnosed with breast cancer at the

age of only 47. Its very difficult as a womens health advocate to say other women have got it wrong.

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middle-class Pakeha women who are quite powerful.

Despite widespread belief among epide-miologists that the evidence doesnt support screening women aged 45 to 49, its unlikely any government would change that now and risk alienating the female vote.

Charlotte Paul, emeritus professor of preventive and social medicine at Otago Medicine, says while women usually count the benefits but

not the harms of mammography, those who are better informed often come to different conclusions. In 2007, she convened a citizens jury 11 women randomly selected from the electoral roll, who then spent a day and a half hearing expert opinions on both sides of the debate on screening for 40- to 49-year-olds. Before hearing the evidence, all the women said the government should fund screening in that age group. But their final verdict came in 10-1 against.

In December, Paul asked Lawrensons advi-sory committee to have a working group assess the latest evidence on overdiagnosis. Lawrenson told North & South that the committee did not have strong views but wanted to come back to the subject. I think theres a poor understanding of risk-benefit ratios and some of the [new] information has been very anti-breast screening and has caused anxiety and concern. A clear message needs to be given to the New Zealand public.

BreastScreen Aotearoas Gregory doesnt believe women have been misled into think-ing screening can only benefit them. There are sections [in the information leaflets] saying we may not find it, and that you may be recalled and not have it.

She also disagrees that most clinicians might tell women, Youre lucky weve found it with a DCIS finding, rather than, This might never harm you.

I think most surgeons would say there is a chance this may not progress but were unable to put a statistic to it.

Auckland breast surgeon Erica Whineray Kelly, whos in the practice where Catherine Hale was treated, says thats certainly true of her advice. No one I know has taken the option of watch and wait but theyre sitting in front of a surgeon so maybe thats the dif-ference. Most have probably already decided, because theyve gone through the panic of being recalled. Its pretty anxiety-provoking and theyll have thought a lot about it over the week before diagnosis. I think people are just relieved to have it detected.

of tomosynthesis, a new imaging technique which takes cross-sectional images from dif-ferent angles.

While issues of overdiagnosis and treatment are on the radar of everyone, Whineray Kelly says mammography is the best weve got and it saves lives. Unless were going to revisit the Cartwright Inquiry [into the unfortunate experiment at National Womens Hospital] we dont have any way of dealing with [DCIS] short of treating it.

For Catherine Hale, relief at the prospect of what she was told was an 80 per cent success rate for treatment of her DCIS still

Unlike a number of breast clinicians who would like to see funded screening start at 40, Whineray Kelly says that while there may be a mortality gain, money is scarce and the num-ber of biopsies required for a diagnosis can be quite high. I dont think mammography is good enough for that age group, and it can give a false sense of security. Pre-meno-pausal women have denser breast tissue, which can make DCIS and cancer more dif-ficult to detect.

Software is improving, and digital mam-mography is steadily replacing film. Her practice is also monitoring the development

women aged 50 to 69 has clear-cut benefits. Thats certainly what the British team report-ed in the Lancet, and Cox concurs. He says overall, about 35 to 49 breast cancer deaths a year are prevented by screening in New Zealand. The rate is lower in the 45 to 49 age group (preventing about one to six cancers a year) and higher in women aged 55 to 74.

Breast cancer death rates began to fall around 1990 before the introduction of widespread screening probably the result of the use of drugs such as tamoxifen, changes in surgical techniques and other improvements in treatment.

Cox believes concentrating on increasing coverage in the 50-plus age group would save more lives than screening those aged 45 to 49.

But BreastScreen Aotearoa clinical leader Marli Gregory says with 72 per cent of the women aged 50 to 69 already being screened, the focus now is on lifting the uptake among Maori and Pacific women, who are less likely to be screened and more likely to die of breast cancer. And, she says, screening the younger women has a flow-on effect which increases the uptake in 50-year-olds.

As a breast physician before heading the screening programme, Gregory was one of a group of 13 Auckland clinicians with a special interest in breast cancer who trenchantly peti-tioned Parliaments health select committee in 2004 for screening to be offered to all women in their 40s. She has since changed that view, saying her appreciation of the liter-ature is greater and Im more experienced.

The early 2000s were politically heated times in the mammography debate. In Nov-ember 2003, Palmerston North couple Debbie and Tim Short presented a 124,000-signature petition to the commit-tee calling for screening to begin at age 40.

By the time the select committee reported back to Parliament in August 2004, saying there wasnt enough evidence that screen-ing was the best option for younger women, the then health minister, Annette King, had already lowered the age of eligibility from 50 to 45. Another female health minister, Jenny Shipley, presided over the 1995 deci-sion to introduce screening in the 50-to-64 age group, although the programme didnt get off the ground until December 1998, by which time Shipley was prime minister.

There was no logic to the decision to start at 45, says Canterbury University professor of cancer epidemiology Ann Richardson, and the extra numbers put the programme under quite a bit of pressure. Richardson, who had been part of the evaluation team of pilot

For Catherine Hale, relief at the prospect of what she was told was an 80 per cent success rate for treatment of her DCIS still came with anxiety.

A mammogram result.

screening has been politicised, and its been a campaign led by middle-class Pakeha women who are quite powerful.

schemes before the introduction of screen-ing, says she didnt agree with the change and believed the government should have waited until the results of a UK-based trial set up to work out whether screening under 50 had additional benefits. It subsequently did not report a significant reduction in mortality.

As Sir Muir Grey [chief knowledge officer to Britains National Health Service] once said, All screening programmes do harm. Some can do good as well. Thats pretty blunt, but screening programmes arent perfect.

The moves to introduce screening and then expand the ages of eligibility were political, vote-catching decisions, says Coney. Its not just a New Zealand phenomenon. It happened in Australia, it happened in Cana-da, it happened in the US. Thats been the problem with this whole area. Its been so politicised, and its been a campaign led by

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came with anxiety. When he told me, Im thinking, Oh shit. I dont need this right now.

She says the 25 days of radiotherapy she completed just last month have left her tired and starting to think she has indeed had breast cancer.

As to the possibility her mammography may have detected a problem she may otherwise have never known she had, Hale has resolved the mind games.

You have to focus on the advice youve been given by the experts. I really feel life is a deck of cards. You get thrown a hand and this is mine. +JAN

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