Vernacchia Fred S, Pena Zachary G
San Luis Diagnostic Center, 1100 Monterey St., Ste. 210, San Luis Obispo, CA 93401, USA.
AJR Am J Roentgenol. 2009 Aug;193(2):582-5. doi: 10.2214/AJR.08.1720.
The purpose of our study was to retrospectively evaluate the impact on recall rates and cancer detection when converting from film-screen to digital mammography in a small community-based radiology practice.
Audits of our institution's records were compiled during a 4-year period: the year before conversion to digital mammography, and the first, second, and third years after conversion. We found that 4,838 film-screenings were performed during the period of audit 1 without the use of the digital system; 6,875 screenings were performed using the digital system during audit 2; 7,379 screenings during audit 3; and 7,294 during audit 4. Cancer detection and recall rates for each of the audits were determined retrospectively. Results were compared between audits using the chi-square test.
Cancer detection rates increased from 4.1/1,000 during film-screenings to 7.9/1,000 (p = 0.01) the year after the introduction of digital mammography. Recall rates also increased the year after digital mammography was introduced, from 6.1% to 10.2% (p < 0.001). Audit 3 showed no statistically significant difference in cancer detection rates from those in audit 1, decreasing to 5.1/1,000 (p = 0.42). However, audit 4 noted an increase in the cancer detection rate to 6.9/1,000.
In this community-based mammography practice, an increase in the cancer detection rate occurred initially during the conversion from film-screen to digital mammography, which subsequently decreased but remained higher than before digital conversion. This study suggests that the new technology alone is responsible for the increased number of cancers detected in patients with dense breasts that were not previously found using film-screening.
本研究的目的是回顾性评估在一个小型社区放射科实践中从胶片-屏片乳腺摄影转换为数字乳腺摄影对召回率和癌症检测的影响。
在4年期间对本机构的记录进行审计：转换为数字乳腺摄影前一年，以及转换后的第一、第二和第三年。我们发现，在审计1期间未使用数字系统进行了4838次胶片筛查；在审计2期间使用数字系统进行了6875次筛查；审计3期间进行了7379次筛查；审计4期间进行了7294次筛查。对每次审计的癌症检测率和召回率进行回顾性确定。使用卡方检验比较各次审计之间的结果。
在引入数字乳腺摄影后的第一年，癌症检测率从胶片筛查期间的4.1/1000增加到7.9/1000（p = 0.01）。在引入数字乳腺摄影后的第一年召回率也有所增加，从6.1%增加到10.2%（p < 0.001）。审计3显示癌症检测率与审计1相比无统计学显著差异，降至5.1/1000（p = 0.42）。然而，审计4指出癌症检测率增加到6.9/1000。
在这个基于社区的乳腺摄影实践中，从胶片-屏片转换为数字乳腺摄影的最初阶段癌症检测率有所增加，随后有所下降，但仍高于数字转换前。本研究表明，仅新技术就导致了在使用胶片筛查以前未发现的致密乳腺患者中检测出的癌症数量增加。
