Otten Johannes D M, Karssemeijer Nico, Hendriks Jan H C L, Groenewoud Johanna H, Fracheboud Jacques, Verbeek André L M, de Koning Harry J, Holland Roland
Department of Epidemiology and Biostatistics, Radboud University Nijmegen Medical Centre, P.O. Box 9101, 6500 HB Nijmegen, The Netherlands.
J Natl Cancer Inst. 2005 May 18;97(10):748-54. doi: 10.1093/jnci/dji131.
The recall rate (i.e., the rate at which mammographically screened women are recalled for additional assessment) in the Dutch breast screening program (0.89% in 2000 for subsequent examinations) is the lowest worldwide, with possible consequences including higher rates of late-detected (i.e., "missed") interval and screen-detected cancers. To estimate the effect of changes in recall rate on earlier detection of cancers, we carried out a blinded review of interval and screen-detected cancers in the Dutch screening program.
A total of 495 sets of screen-negative mammograms (prediagnostic mammogram and the immediate previous mammogram) were collected from women participating in the biennial Dutch screening program. Of these, 250 were from control subjects, and 245 were from women who were subsequently diagnosed with breast cancer (123 interval and 122 screen-detected cancers). These mammograms were read by 15 radiologists who specialize in screening mammography and were blinded to outcome. Mean detection sensitivities for different false-positive rates were calculated using a linear mixed model. These results were used to calculate the effect of recall rate adjustment on earlier detection of cancers and numbers of false-positives.
Increasing the recall rate to 2.0% would increase the detection rate from 4.20 per thousand to 4.52 per thousand due to the earlier detection of interval cancers. Moreover, 0.54 per thousand of the screen-detected cancers would be detected 2 years earlier (late screen-detected cancers). At recall rates of 3.0% and 4.0% the detection rate would increase to 4.58 per thousand and 4.63 per thousand, respectively, and 0.64 per thousand and 0.72 per thousand, respectively, of the screen-detected cancers would be detected 2 years earlier. For each 1.0% incremental increase in recall rate above 5.0%, the detection rate would increase by approximately 0.03 per thousand, with positive predictive values decreasing to below 10%.
Breast cancer can be detected earlier by lowering the threshold for recall, especially for recall rates of 1%-4%. With further recall rate increases, cancer detection levels off with a disproportionate increase of false-positive rates.
荷兰乳腺癌筛查项目的召回率（即接受乳腺钼靶筛查的女性被召回进行进一步评估的比率，2000年后续检查的召回率为0.89%）是全球最低的，可能导致包括更高的晚期（即“漏诊”）间期癌和筛查发现癌发生率等后果。为了评估召回率变化对癌症早期发现的影响，我们对荷兰筛查项目中的间期癌和筛查发现癌进行了盲法回顾。
从参与两年一次荷兰筛查项目的女性中总共收集了495组筛查阴性的乳腺钼靶片（诊断前钼靶片和紧接之前的钼靶片）。其中，250组来自对照对象，245组来自随后被诊断为乳腺癌的女性（123例间期癌和122例筛查发现癌）。这些钼靶片由15位专门从事乳腺钼靶筛查且对结果不知情的放射科医生阅读。使用线性混合模型计算不同假阳性率下的平均检测敏感度。这些结果被用于计算召回率调整对癌症早期发现和假阳性数量的影响。
将召回率提高到2.0%会使检测率从千分之4.20提高到千分之4.52，这是由于间期癌被更早发现。此外，每千例筛查发现癌中有0.54例会被提前2年发现（晚期筛查发现癌）。召回率为3.0%和4.0%时，检测率将分别提高到千分之4.58和千分之4.63，每千例筛查发现癌中分别有0.64例和0.72例会被提前2年发现。召回率高于5.0%时，每增加1.0%，检测率将增加约千分之0.03，阳性预测值降至10%以下。
通过降低召回阈值可以更早发现乳腺癌，特别是召回率在1% - 4%时。随着召回率进一步提高，癌症检测水平趋于平稳，但假阳性率会不成比例地增加。
