Observations Breast Cancer Screening

An independent review is under way

BMJ 2011; 343 doi: http://dx.doi.org/10.1136/bmj.d6843 (Published 25 October 2011) Cite this as: BMJ 2011;343:d6843
  1. Mike Richards, national clinical director for cancer and end of life care, Department of Health, London
  1. Mike.Richards{at}ncat.nhs.uk

The BMJ has published several articles over the past few years raising concerns about the accuracy and transparency of information provided to women about the benefits and harms of mammography screening for breast cancer (BMJ 2006;332:538, doi:10.1136/bmj.332.7540.538; 2009;338:b86, doi:10.1136/bmj.b86; 2010;340:c3106, doi:10.1136/bmj.c3106). Last month the professor of complex obstetrics Susan Bewley sent us for publication an open letter to England’s cancer tsar (BMJ 2011;343:d6894, doi:10.1136/bmj.d6894). Here is the response from Mike Richards

Dear Susan

Your letter raises several important issues. These include the current state of the evidence relating to the benefits and harms of breast screening; how this information is communicated to women in order to promote informed choice; and the process by which decisions on screening are made in this country, including my own role. I welcome this opportunity to discuss all these issues.

When I became national cancer director 12 years ago the NHS breast screening programme was one of the few aspects of cancer service delivery that was generally judged to be working well. Broad decisions on screening programmes were, and still are, taken by the independent UK National Screening Committee, which advises ministers in all four UK countries. In addition to this, ministers in England were, and still are, advised by the independent Advisory Committee on Breast Cancer Screening (ACBCS). This committee, with membership largely nominated by the appropriate professional bodies, provides advice on the effective running of the existing screening programme and on the evidence underpinning and presentation of information provided by the screening programme.

My role in screening has largely been to ensure that the NHS delivers on the government’s commitments, though I do of course provide my own opinion to ministers if requested. Progress on screening commitments is regularly discussed at the Department of Health’s Cancer Programme Board.

Over the past 12 years the NHS breast screening programme has, on the advice of the ACBCS, been improved and extended, firstly from age 50-64 years to 50-70 years (with each woman being routinely invited seven rather than five times in her life). A further extension, from 47-73 (with a total of nine invitations) is, on the advice of independent academics and with the support of the ACBCS, being introduced through randomisation. This is likely to be the largest randomised controlled trial ever undertaken in the world and will provide invaluable evidence on the benefits and harms of additional screening rounds.

Like you, I believe that screening programmes should be based on the best available evidence. This evidence is of two broad types. The first type is the randomised controlled trials on which the original decisions to introduce screening were made, which now have many additional years of follow-up. The second is a range of observational and case-control studies that have examined the effect of screening programmes in practice. The advice that ministers and I receive from the ACBCS is that breast screening saves lives and that the benefits considerably outweigh the harms. This advice is in line with the findings published in a monograph from the World Health Organization’s International Agency for Research on Cancer. This concluded that screening women aged 50-69 years old reduced mortality by 35%.1 On the basis of the experience of breast screening in England, the ACBCS estimated that for every 400 women screened regularly over a 10 year period, one woman fewer will die from breast cancer than had they not been screened.2

As with any medical intervention, screening has potential risks that must be carefully evaluated against the benefits. Work undertaken by eight leading international scientists calculated that the benefit of mammographic screening in terms of lives saved is greater than the harm in terms of overdiagnosis—concluding that an estimated 2-2.5 lives are saved for every overdiagnosed case of breast cancer.3 I am, however, well aware that a contrary view has been provided by the Cochrane collaboration.

I agree with you that the sheer weight of numbers supporting one side of an argument does not necessarily make it right. Nor, however, does the appellation of a Cochrane review necessarily mean that the views of the minority of experts are right either. However, I do believe that the ongoing controversy should, if at all possible, be resolved. Therefore some weeks ago I initiated the following actions.

  • 1. An independent review of the research evidence (randomised controlled studies and observational studies) is being undertaken, led by myself and Harpal Kumar, chief executive at Cancer Research UK. We are seeking independent advisers for this review who have never previously published on the topic of breast cancer screening.

  • 2. Once the independent review has concluded, evidence will be presented at a workshop hosted by Cancer Research UK to which experts from both sides of the argument will be invited.

  • 3. A new process for developing written information for the public about each screening programme is being established on behalf of NHS cancer screening programmes. This will take account of current thinking on how to synthesise information on benefits and harms and how to present these so as to promote informed choice. An independent team is being commissioned to lead this work and will consult widely on the new process.

  • 4. The breast screening leaflet will be one of the first products to be revised through this new process.

I hope this reassures you that I take the current controversy very seriously. I will do my best to achieve consensus on the evidence, though I realise this may not ultimately be possible. Should the independent review conclude that the balance of harms outweighs the benefits of breast screening, I will have no hesitation in referring the findings to the UK National Screening Committee and then ministers. You also have my assurance that I am fully committed to the public being given information in a format that they find acceptable and understandable and that enables them to make truly informed choices.

Notes

Cite this as: BMJ 2011;343:d6843

References