Breast Imaging Of Low-Risk Women

Use of mammography and breast ultrasound procedures soared by over 30 per cent among women aged 25-44 in the six months following Kylie Minogue's breast cancer diagnosis, says a new study from the University of Melbourne. There was also a sharp rise in the number of women aged 25-34 years who underwent breast biopsies - but this surge in screening activity did not lead to the detection of more cases of breast cancer.

30 Percent Increase In Breast Imaging Of Low-Risk Women As A Result Of Kylie's Breast Cancer, HEALTH and MEDICAL EDUCATION The study, published this week in the International Journal of Epidemiology, is the first to use Medicare data to examine the impact of the intense publicity that surrounded this announcement on breast imaging, biopsies and operations to remove breast tumors. Study leader Dr Margaret Kelaher, from the University of Melbourne's Melbourne School of Population Health, and colleagues found that in the six months following Minogue's diagnosis in April 2005: Breast imaging in 25-34 year old women rose by 33 per cent; Breast biopsies in women 25-34 increased by 46 per cent; Breast imaging in women aged 35-44 rose by 25 per cent; Biopsies in women aged 35-44 increased by 37 per cent.

However, the rates of operations to remove breast cancers did not change significantly, suggesting that the flurry of screening activity led to many "false positives". "Raising women's awareness of the need to get screened is a generally good thing," Dr Kelaher said. "But these findings suggest that thousands of additional imaging procedures and biopsies did not improve breast cancer detection among young women. "It appears there has been a situation where publicity has led to many low risk women using - and probably overusing - screening services. "We need to improve the targeting of health messages and the confidence of women and their doctors in early breast cancer detection recommendations." Dr Kelaher said the publicity could have raised doctors' perception about breast cancer risk and increased concerns, both medical and legal, about missed diagnoses in younger women. The researchers also suggest that the influx of low-risk women into the screening system may have damaging effects by reducing the system's capacity to deal with higher risk women.

Dr Kelaher said Kylie Minogue had been a great ambassador for breast cancer awareness, but the publicity surrounding her case highlighted the need for better efforts at "managing the message." "The visibility of a celebrity's illness provides an opportunity to address a huge health problem like breast cancer," she said. "But when that celebrity is from a low risk group, it also has the potential to undercut the appropriateness and cost effectiveness of health service delivery. "Consultation between a celebrity's PR team and public health agencies on how to shape and disseminate the information could help create a message with the best chances of furthering the quality of care and sound public health practice."

Dr Julie Miller, consultant surgeon at the Royal Melbourne Hospital and senior lecturer in the Department of Surgery at the University of Melbourne, is a co-author of the study. "It's important that women are breast-aware, and consult their doctor if they are concerned about any changes in their breasts,'' Dr Miller said. "However there is no role for routine screening of women under 40 who do not have symptoms or a strong family history. "This study shows that all the extra worry and expense was unwarranted and that the current recommendations for breast cancer screening are appropriate."

Breast MRI scans 'commonly wrong'

But while researchers found five out of six scans which suggested a problem were wrong, they were nonetheless very effective at spotting invasive cancers. And while false-positives caused anxiety, the study did not find women were rashly opting for mastectomies. The findings were published in the Annals of Oncology. Women with certain genes have as much as an 85% risk of breast cancer.

In the UK, NHS guidelines say that a woman with a family history of the disease may be offered yearly MRI scans if her doctors think it is appropriate, in addition to the recommended mammogram. MRI scans - which use magnetic resonance imaging - are more sensitive than standard mammograms, and as such are seen as particularly effective in picking up early breast cancers in younger women with denser breast tissue.

But this very sensitivity is what makes them more likely to spot abnormalities which may turn out to be completely benign. Researchers at the Hereditary Cancer Clinic at Nijmegen Medical Centre followed 196 women with the BRCA1 or BRCA2 gene mutation which has been linked to breast cancer. On their first visit, they were asked whether they had a preference for ongoing surveillance in the form of scans, or whether they would rather have their breasts removed as a precaution. About 30% said they wanted a protective mastectomy, three expressed no preference and the others wanted regular check-ups.

 All also went on to receive a scan. About 83% of the MRI scans which appeared to detect a tumour were later found to be so-called "false positives". However, the positive scan appeared to do little to sway decisions on breast removal. Some 90% of the group who had wanted a mastectomy went on to have one, while fewer than a third of those who received a positive result and had originally opted for surveillance opted for breast removal. "The final decision to actually undergo prophylactic mastectomy appeared to be determined more frequently by a woman's prior preference than by a positive scan," said Dr Nicoline Hoogerbrugge, who led the research. There was little information available about how women made the choice, she added. "Both genetic counselling and breast cancer surveillance are events in the entire decision-making process, but appear to have a limited impact."

But the researchers did confirm that the MRI scan was more effective in picking up genuine tumours and pre-cancerous developments. ;The proportion of true-positives for mammography was 41%, while for MRI it was 60%. There was little difference between the two when it came to providing the all clear, with both equally unlikely to suggest there was nothing wrong when a growth was in fact present. Breakthrough Breast Cancer said the findings should not curtail access to MRI scans for those women at high risk. "MRI, together with mammography, is the most effective form of screening for this group of women although this method can result in false positives," said head of policy Dr Sarah Rawlings. "It is vital that all those eligible have access to this service and also receive clear and accurate information about the risks and benefits of MRI so they can make an informed decision."

Breast Cancer Care clinical director Dr Emma Pennery said: "While MRIs can result in false positive findings, this is far outweighed by their ability to detect tumours earlier in their development compared to mammography in high risk groups.

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