Broeders M J, Peer P G, Straatman H, Beex L V, Hendriks J H, Holland R, Verbeek A L
Department of Epidemiology and Biostatistics, University Medical Centre Nijmegen, P.O. Bpx 9101, 6500 HB Nijmegen, the Netherlands.
Int J Cancer. 2001 Apr 15;92(2):303-8. doi: 10.1002/1097-0215(200102)9999:9999<::aid-ijc1186>3.0.co;2-b.
Age-standardised breast cancer mortality rates have been stable for decades. However, rates have started to decline in several Western countries. In countries where population-based screening programmes for breast cancer were introduced in the late 1980s or early 1990s, the key question now is to what extent screening is responsible for the reported declines in mortality. This study compares breast cancer mortality rates in Nijmegen, where a screening programme for breast cancer was introduced in 1975, to a control city, Arnhem, and to the Netherlands as a whole over a 20-year period. Age-standardised breast cancer mortality rates as well as age-standardised mortality ratios were calculated for successive calendar years from 1969 to 1997. Further, a tailor-made period-cohort-group Poisson regression model was fitted. Figures displaying age-standardised mortality rates and ratios showed inconclusive patterns with regard to the expected impact of screening. Depending on when mortality rates were allowed to deviate between populations, the period-cohort-group analysis indicated a non-significant 6% to 16% reduction in breast cancer mortality after 2 decades in favour of the Nijmegen female population. Possible explanations are discussed as to why the mortality reductions reported by randomised trials might not be observed in a public health screening programme, such as the Nijmegen programme, evaluated by comparisons of geographical trends.
几十年来，年龄标准化乳腺癌死亡率一直保持稳定。然而，在一些西方国家，该死亡率已开始下降。在20世纪80年代末或90年代初引入基于人群的乳腺癌筛查项目的国家，现在的关键问题是筛查在多大程度上导致了所报道的死亡率下降。本研究比较了1975年引入乳腺癌筛查项目的奈梅亨市、对照城市阿纳姆以及整个荷兰在20年期间的乳腺癌死亡率。计算了1969年至1997年连续历年的年龄标准化乳腺癌死亡率以及年龄标准化死亡率比。此外，拟合了一个量身定制的时期队列组泊松回归模型。显示年龄标准化死亡率和比率的图表在筛查的预期影响方面呈现出不确定的模式。根据允许不同人群之间死亡率出现偏差的时间，时期队列组分析表明，20年后，奈梅亨女性人群的乳腺癌死亡率无显著下降，降幅为6%至16%。对于为何在通过地理趋势比较评估的公共卫生筛查项目（如奈梅亨项目）中未观察到随机试验所报告的死亡率降低情况，文中讨论了可能的解释。
