Screening for breast cancer
Because the prognosis of breast cancer is
closely related to stage at diagnosis, it would seem reasonable to hope that a
population screening programme which could detect tumours before they come to
the patient’s notice may reduce mortality from breast cancer. A number of
studies has indeed shown
that breast screening by mammography in women
over the age of 50 will reduce cause-specific mortality by up to 30 per cent.
Following the publication in 1987 of the Forrest report the National Health
Service in the UK has launched a programme of 3-yearly mammographic screening
for women between the ages of 50 and 64. The introduction of this programme has
undoubtedly improved the quality of breast cancer services but a number of
questions remains unanswered including the value of screening women under 50 and
the ideal interval between screenings. The psychological consequences of false
alarms or false reassurances still need to be addressed and self-examination
programmes which have failed to show any benefit for the population in terms of
earlier or decreased mortality from breast cancer still remain controversial.
Figure 46.40 illustrates some benefits and disadvantages of screening. The
senior author remains doubtful regarding the value of a screening programme in
terms of the wider implications of healthcare planning.