Welch H G, Fisher E S
Department of Veterans Affairs Medical Center, White River Junction, VT, USA.
J Natl Cancer Inst. 1998 Sep 16;90(18):1389-92. doi: 10.1093/jnci/90.18.1389.
To provide some sense of the general frequency and timing of diagnostic testing following screening mammography in the United States, we investigated the experience of women screened in the Medicare population.
By use of Medicare's National Claims History System, we identified a cohort (n=23172) of women 65 years old or older screened during the period from January 1, 1995, through April 30, 1995, and tracked each woman over the subsequent 8 months for the performance of additional breast imaging and biopsy procedures. Using two claims-based definitions for newly detected breast cancer, we also estimated the positive predictive value of screening mammography.
For every 1000 women aged 65-69 years who underwent screening, 85 (95% confidence interval [CI]=79-91) had follow-up testing in the subsequent 8 months; 76 (95% CI=71-82) had additional breast imaging, and 23 (95% CI=20-26) had biopsy procedures. Corresponding numbers for women aged 70 years or more were similar. Some women underwent repeated examinations; 13% of those receiving diagnostic mammograms had more than one; 11% of those undergoing biopsy procedures had more than one. About half of the women who underwent a biopsy had the procedure more than 3 weeks after the imaging test upon which the decision to perform a biopsy was presumably made. The estimated positive predictive value of an abnormal screening mammogram (defined as a mammogram that engendered additional testing) was 0.08 (95% CI=0.06-0.10) for women aged 65-69 years and 0.14 (95% CI=0.12-0.16) for women aged 70 years or more.
Additional testing is a frequent consequence of screening mammography and may require a considerable period of time to come to closure. The need for additional testing, however, is weakly predictive of cancer.
为了解美国乳腺钼靶筛查后诊断性检查的总体频率和时间安排，我们调查了医疗保险人群中接受筛查的女性的情况。
利用医疗保险的全国理赔历史系统，我们确定了一个队列（n = 23172），该队列由1995年1月1日至1995年4月30日期间接受筛查的65岁及以上女性组成，并在随后的8个月内跟踪每位女性进行额外的乳房成像和活检程序的情况。使用两种基于理赔的新检测乳腺癌的定义，我们还估计了乳腺钼靶筛查的阳性预测值。
每1000名接受筛查的65 - 69岁女性中，有85名（95%置信区间[CI]=79 - 91）在随后的8个月内进行了后续检测；76名（95% CI=71 - 82）进行了额外的乳房成像，23名（95% CI=20 - 26）进行了活检程序。70岁及以上女性的相应数字相似。一些女性接受了重复检查；接受诊断性乳腺钼靶检查的女性中有13%进行了不止一次检查；接受活检程序的女性中有11%进行了不止一次检查。大约一半接受活检的女性在据推测做出活检决定的成像检查后3周以上才进行活检。对于65 - 69岁女性，异常乳腺钼靶筛查（定义为引发额外检测的乳腺钼靶检查）的估计阳性预测值为0.08（95% CI=0.06 - 0.10），对于70岁及以上女性为0.14（95% CI=0.12 - 0.16）。
额外检测是乳腺钼靶筛查的常见结果，可能需要相当长的时间才能完成。然而，额外检测的需求对癌症的预测性较弱。
