Letters

Mammography after treatment for breast cancer

Recently, during preliminary pilot work for a randomised trial of different approaches to follow up, we reviewed the medical records of 145 women who were being followed up after treatment for breast cancer at two district general hospitals. The results caused us some concern and merit wider discussion. We audited the interval between the date that the last mammogram was due, according to the clinician's stated policy for the patient, and the date it was done (or the audit date if it had never been done). In 35% (50 patients) the delay was six months or more, and in 21% (30 patients) it was 12 months or more.

Although the audit was restricted to two hospitals, and we cannot say for certain that we have identified a more widespread problem, we believe these findings raise three important issues. Firstly, there is no reason why quality control in a follow up surveillance programme should be less rigorous than in a primary screening programme - the same organisational principles should apply. Secondly, patients who have had one breast cancer are at approximately sixfold increased risk of a second primary cancer² and are less likely to comply readily with surveillance mammograms, even if aged over 64. Thirdly, and most importantly, many clinicians request mammographic surveillance of breast cancer patients more frequently than the national programme on the basis of evidence that mammography leads to earlier diagnosis of second primary cancers³ or local recurrence.⁴ However, debate remains about the appropriate surveillance interval for this purpose, as well as the overall effect of earlier diagnosis on disease control, quality of life, and survival.⁵

We feel that there is a need to clarify the objectives of mammographic surveillance in women with breast cancer in remission and to decide on the most appropriate screening interval. This would be best done by a randomised trial. Furthermore, there is a need to ensure that whatever surveillance policy is adopted, it is carried out effectively. It may be that screening units, which are already equipped to offer a high quality mammography service with a recall system, are best placed to take on this role - but they must be adequately resourced to do so.

E Grunfeld, D Mant, M P Vessey, D J Cole, J A Stewart 

Department of Public Health and Primary Care, University of Oxford, Oxford OX2 6HE Department of Primary Medical Care, University of Southampton, Southampton SO1 6ST University of Oxford, Oxford OX2 6HE Churchill Hospital, Oxford OX3 7LJ Northamptonshire Centre for Oncology, Northampton General Hospital, Northampton NN1 5BD.

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