The introduction of mammographical screening has had little effect on the trend in breast-conserving surgery: a population-based study in Southeast Netherlands

In addition to reducing breast cancer mortality, breast cancer screening pr ogrammes are expected to increase the proportion of patients who can underg o breast-conserving surgery. Trends in the use of breast-conserving surgery (BCS) in Southeast Netherlands between 1990 and 1998 were studied in relat ion to the gradual introduction of mammographical screening for women 50-69 years of age between 1992 and 1996. The characteristics of the tumours det ected by the screening programme or outside of the programme were compared, to see whether this might clarify the observed trends. In the period 1990- 1998, 4788 patients were diagnosed with invasive, operable breast cancer, o f whom 2341 were 50-69 years of age. Although the screening programme resul ted in a larger proportion of patients with small tumours and more favourab le tumour characteristics, no increase was observed in the use of BCS for p atients 5069 years of age in the period 1990-1998 (64% in 1990 and 1998). P atients with a screening-detected tumour, however, were more likely to unde rgo breast conservation compared with those presenting clinically (68% vers us 54%; P <0.0001). In conclusion, no increase in the proportion of breast- conserving surgical procedures was observed in Southeast Netherlands among patients 50-69 years of age in the period 1990-1998, during the introductio n of mass mammographical screening for this group. Screening, however, resu lted in a larger proportion of patients with small tumours with more favour able characteristics, who are better candidates for breast conservation. (C ) 2001 Elsevier Science Ltd. All rights reserved.