Department of Radiation Sciences, Umeå University, 901 87 Umeå, Sweden.
J Med Screen. 2012 Mar;19(1):14-9. doi: 10.1258/jms.2012.011104. Epub 2012 Feb 21.
To estimate the level of overdiagnosis of all breast cancers and of invasive breast cancers in women aged 40-49 invited to the subsequent screening rounds in the Swedish service-screening programme 1986-2005.
To estimate the level of overdiagnosis in subsequent screening, the rate ratios (RR) of the breast cancer incidence in the study group (women in areas with screening in ages 40-49) and the control group (women in areas with no screening in ages 40-49) were calculated for all breast cancers and for invasive breast cancers. The RR estimates were adjusted for the prescreening difference in incidence between study and control group and for lead time.
The prescreening incidence rate ratio was estimated at 0.92 (95% confidence interval [CI]: 0.88-0.97). The number of breast cancer cases and person-years were 6047 and 3.8 million, and 7790 and 5.2 million, in the study group and control group respectively during the study period. The RR estimate for all cancers was 1.01 (95% CI: 0.94-1.08) when adjusted for prescreening difference and a lead time of 1.2 years. The corresponding estimate for invasive breast cancers was 0.95 (95% CI: 0.88-1.02).
We found no significant overdiagnosis for women aged 40-49 in the Swedish service screening programme with mammography.
评估所有在 1986 年至 2005 年期间被邀请参加瑞典服务筛查项目后续筛查轮次的 40-49 岁女性中乳腺癌及浸润性乳腺癌的过度诊断水平。
为了评估后续筛查中的过度诊断水平，通过计算研究组（40-49 岁有筛查地区的女性）和对照组（40-49 岁无筛查地区的女性）的乳腺癌发病率比率（RR），对所有乳腺癌和浸润性乳腺癌的过度诊断水平进行评估。RR 估计值根据研究组和对照组之间的筛查前发病率差异以及领先时间进行了调整。
在筛查前，发病率比率估计值为 0.92（95%置信区间[CI]：0.88-0.97）。在研究期间，研究组和对照组的乳腺癌病例数和人年数分别为 6047 例和 380 万例，7790 例和 520 万例。当调整了筛查前差异和 1.2 年的领先时间后，所有癌症的 RR 估计值为 1.01（95% CI：0.94-1.08）。浸润性乳腺癌的相应估计值为 0.95（95% CI：0.88-1.02）。
我们在瑞典服务筛查项目的乳腺 X 线摄影筛查中未发现 40-49 岁女性的显著过度诊断。
