Results from the UKNHS breast screening programme 1994-1999

Objective-To present results from the NHS breast screening programme (NHSBS P) from 1994 through to 1999 and to examine the extent to which interim tar gets are being achieved. Methods-Data were collated from all screening programmes in the UK on stand ard statistical returns. Performance of the screening programme was evaluat ed using calculated targets based on comparison with the Swedish two counti es (STC) randomised controlled trial. Results-In the early years of screening (1988-1993), the NHS programme was detecting more DCIS but considerably less invasive cancers than expected, b ased on the STC trial. Since the screening year 1993/94 (1 April to 31 Marc h) the standardised detection ratio (SDR) measure of the detection of invas ive cancers has increased by 36% from 0.83 to 1.13. The SDR has been greate r than 1 since 1996/97 suggesting that the NHSBSP has only been screening a s efficiently as the STC trial since this date. Uptake for screening has be en relatively stable over time at approximately 75%. Conclusions The NHSBSP has made considerable advances in performance since its inception in 1988 and screening uptake and age standardised invasive ca ncer detection rates are (by 1999) well in excess of targets. The early yea rs of screening were characterised by good uptake but a low sensitivity for the detection of invasive cancers. It is anticipated that the screening pr ogramme will have an increasing impact on breast cancer mortality, particul arly in the 55-69 year age group over the coming years.