Balanced, accurate information is essential to ensure that the benefits of breast cancer screening outweigh its risks, says Hilary Jefferies
Serious shortcomings in the information given to women in the UK who attend for breast cancer screening have been raised by research published online by the British Medical Journal (Gøtzsche et al, 2009).
Three years ago, researchers at the Nordic Cochrane Centre found that breast screening leaflets in six countries, including the UK, omitted to mention the most important harms of screening – the overdiagnosis and overtreatment of healthy women (Gøtzsche et al, 2009).
Now they argue that, although the UK leaflet Breast Screening: The Facts has been updated, it continues to emphasise the benefits and little advice is given about the risks of false positive diagnoses.
Routine breast screening in the UK detects twice as many cases of breast cancer each year than 10 years ago, with 14,110 cases diagnosed in 2007–2008. This may be as a result of an increase in compliance, as more than 1.7 million women were screened in 2007–2008, a rise of 4.3% on the previous year.
However, several authors (Thornton et al, 2003) have expressed concerns over this, and state that, with a doubling of the detection rate of breast cancer, there may also be a doubling of harm. False-positive needle core biopsies – the mainstay of non-operative diagnosis – may lead to mismanaging women. So, while it may be presumed that screening leads to less invasive surgery or simpler treatment, it may actually result in more surgery because of overdiagnosis.
Screening for cervical cancer remains poor, with only 81% of women in England, 83% in Scotland and 74% in Wales being screened. In England in 2003–2004, 4.4 million women were invited for screening and 3.5 million attended, and 260,000 abnormal smears were detected. Reasons often given for not attending for a smear are anxiety and pain. However, early detection of precancerous changes in the cervical stroma may lead to the removal of the affected tissue, or conservative management by keeping the woman under review. Any cervical cancers detected at screening can be treated quickly.
So how do you reply to the question ‘Do I go for my screening or not?’ The answer must be ‘Go for it’ and to encourage your patients, friends and families to attend routine screening, particularly if there is a family history of cancer of the colon, breast, endometrium or ovary.
But what about the risks of overtreatment?
Our role as nurses is to give information with the latest evidence about the disease for which the screening is being performed and to be aware of the benefits and the potential harm so informed decisions can be made. Positive results may be confirmed and the risk of false positive results reduced by immunohistochemistry tests on biopsies and blood tests for tumour markers.
While there may be anxiety and fear associated with screening, without it there may be a significant risk that a cancer may not be detected, treatment may not be available if the disease is advanced, and prognosis poor. We need a balanced view of all the information to ensure screening benefits outweigh the risk of harm.
Hilary Jefferies, Macmillan clinical nurse specialist, Birmingham Women’s Hospital, Birmingham
Gøtzsche, P. et al (`2009) Breast screening: the facts – or maybe not? British Medical Journal; 338: b86.
Thornton, H. et al (2003) Women need better information about routine mammography. British Medical Journal; 327: 101–103.