West Breast Screening Quality Assurance
Regional Director of Breast Screening Quality Assurance produces a report
each year describing performance of programmes in the North West Region
against national standards and current issues facing the Breast Screening
Programme. The report is circulated widely to professionals and organisations
within the health sector.
are eleven screening programmes in the North West with eligible populations
ranging from 17,000 to 130,000 women. The Breast Screening Programme
in the North West screens approximately 540,000 women over a screening
round of three years.
1999, the two QA Reference Centres in the region were merged to a single
QARC based at West Pennine Health Authority, Oldham. Two QA teams of
professional co-ordinators were retained and formally appointed for
a period of three years.
1999, the way that the screening interval is measured was changed. This
effectively means that programmes now have to aim for a median interval
of 36 months instead of 38. All programmes have been required to submit
plans to achieve the new target.
screening population has been subject to growth in the last five years
due to the post-war baby boom. Overall, the number of women invited
for screening grew by 9% from 1994 – 1999 (range –9% to 34%) and growth
is expected to continue until at least 2014. The number of women self-referring
for breast screening has increased dramatically from 4794 in 1994-95
to 11450 in 1998-99. This trend is also expected to continue as more
women that have already been screened wish to continue after the age
shortage of medical manpower has begun to affect the screening programme
in the North West. Four programmes have had or are currently experiencing
severe problems in recruiting Consultant Radiologists, and there are
a number of unfilled Consultant Pathology and Surgery posts.
programmes in the North West benefited from a substantial allocation
of equipment from the New Opportunities Fund in 1999. In total, 22 replacement
and 5 additional x-ray sets, 3 replacement and 2 additional trailers,
and 6 replacement ultrasound machines have been funded.
1998-99, 194,124 women were invited and 159,262 women screened in the
North West. 896 cancers were detected of which 712 were invasive.
(proportion of eligible women screened within 36 months) ranged from
58% in Manchester to 75% in South Lancashire in 1998-99. The results
are deflated by the inclusion of all women aged 50, 51 and 52 in the
denominator (only one third will have been invited at any time) but
reflect factors such as poor compliance and slippage.
of invitations for screening was above the target of 70% in all programmes
in 1998-99, ranging from 71% in Liverpool to 83% in Crewe. Variation
is largely due to the socio-economic profile of the population. Uptake
at the prevalent screen is lower than the incident. Uptake rates in
women who have previously failed to attend are consistently low.
proportion of women recalled for assessment at the prevalent screen
ranged from 5.4% to 13.6% in 1998-99. A number of programmes had recall
rates that were above the minimum standard of ≤10%. All programmes
achieved the target standard of ≤5% for the incident screen.
proportion of women placed on early recall (to be assessed at six or
twelve months) has dropped over time. Results show that in all programmes
<1% of women were placed on early recall in 1998-99 and one programme
(North Lancashire and South Cumbria) has eliminated the practice altogether,
which is excellent.
proportion of women that receive a non-operative diagnosis has increased
considerably in the last five years. The majority of programmes achieved
the minimum standard of ≥70% in 1998-99. Those that did not were
limited by operational constraints.
is variation in the rate of benign biopsy, particularly at the prevalent
screen, where the numbers are small. High rates are usually linked to
low non-operative diagnosis rates.
rates of invasive cancers varied across the North West in 1998-99. The
data are generally unreliable for a single year in many programmes because
the numbers are small, and results are provided for the last four years
to assist in reviewing performance. A number of programmes have achieved
cancer detection rates well above the target standard. Those programmes
with detection rates below the minimum standard have been asked to investigate
the possible reasons.
age standardised detection ratio has been calculated for each programme
over a period of four years. Results for the prevalent screen are generally
good, but results for the incident screen for some programmes are low
and are being investigated by the local and regional team.
target for detection of small invasive cancers (<15mm in diameter)
was achieved by most programmes at both the prevalent and incident screen
in 1998-99. Numbers of cases are small for most, particularly at the
prevalent screen, so results are sometimes unreliable. Some programmes
managed to achieve excellent small cancer detection rates.
of in situ cancers is enormously varied across the North West. It is
anticipated that a region-wide audit and research study that is planned
to start in 2000 will help to explain this.
on the occurrence of interval cancers (those occurring in the three
years after a negative screen) has only been published for Greater Manchester
and Lancashire. A project is underway in Merseyside and Cheshire to
ascertain interval cancers in the same way. The published data show
slightly disappointing results, particularly in the first and second
years after screening where rates exceed the target, however they are
comparable with other regions.
analysis of the performance of individual programmes over the last four
years has been provided. This includes operation information that is
relevant in interpreting the results.
results from the annual British Association of Surgical Oncologists
Breast Audit have been included in the report. Reassuringly, all cases
of screen-detected breast cancer in 1998-99 were treated by a breast
specialist with the exception of one (due to patient preference).
further information, please contact:
West Breast Screening QA Reference Centre
of Public Health
Pennine Health Authority
Tel: (+44) 161