Skaane Per, Kshirsagar Ashwini, Hofvind Solveig, Jahr Gunnar, Castellino Ronald A
Department of Radiology, Ullevaal University Hospital, University of Oslo, Norway.
Acta Radiol. 2012 Apr 1;53(3):241-8. doi: 10.1258/ar.2011.110452. Epub 2012 Jan 27.
Double reading improves the cancer detection rate in mammography screening. Single reading with computer-aided detection (CAD) has been considered to be an alternative to double reading. Little is known about the potential benefit of CAD in breast cancer screening with double reading.
To compare prospective independent double reading of screen-film (SFM) and full-field digital (FFDM) mammography in population-based screening with retrospective standalone CAD performance on the baseline mammograms of the screen-detected cancers and subsequent cancers diagnosed during the follow-up period.
The study had ethics committee approval. A 5-point rating scale for probability of cancer was used for 23,923 (SFM = 16,983; FFDM = 6940) screening mammograms. Of 208 evaluable cancers, 104 were screen-detected and 104 were subsequent (44 interval and 60 next screening round) cancers. Baseline mammograms of subsequent cancers were retrospectively classified in consensus without information about cancer location, histology, or CAD prompting as normal, non-specific minimal signs, significant minimal signs, and false-negatives. The baseline mammograms of the screen-detected cancers and subsequent cancers were evaluated by CAD. Significant minimal signs and false-negatives were considered 'actionable' and potentially diagnosable if correctly prompted by CAD.
CAD correctly marked 94% (98/104) of the baseline mammograms of the screen-detected cancers (SFM = 95% [61/64]; FFDM = 93% [37/40]), including 96% (23/24) of those with discordant interpretations. Considering only those baseline examinations of subsequent cancers prospectively interpreted as normal and retrospectively categorized as 'actionable', CAD input at baseline screening had the potential to increase the cancer detection rate from 0.43% to 0.51% (P = 0.13); and to increase cancer detection by 16% ([104 + 17]/104) and decrease interval cancers by 20% (from 44 to 35).
CAD may have the potential to increase cancer detection by up to 16%, and to reduce the number of interval cancers by up to 20% in SFM and FFDM screening programs using independent double reading with consensus review. The influence of true- and false-positive CAD marks on decision-making can, however, only be evaluated in a prospective clinical study.
双重阅片可提高乳腺钼靶筛查中的癌症检出率。单阅片结合计算机辅助检测（CAD）被认为是双重阅片的一种替代方法。关于CAD在双重阅片乳腺筛查中的潜在益处知之甚少。
比较在人群筛查中，屏-片乳腺摄影（SFM）和全视野数字化乳腺摄影（FFDM）的前瞻性独立双重阅片，与对筛查发现的癌症及随访期间诊断出的后续癌症的基线乳腺钼靶片进行回顾性独立CAD分析的性能。
本研究获得伦理委员会批准。对23923例（SFM = 16983例；FFDM = 6940例）筛查乳腺钼靶片采用5分制癌症概率评分量表。在208例可评估的癌症中，104例为筛查发现的，104例为后续（44例间期癌和60例下一轮筛查发现的癌）癌症。后续癌症的基线乳腺钼靶片在不知情癌症位置、组织学或CAD提示的情况下进行回顾性一致分类，分为正常、非特异性微小征象、显著微小征象和假阴性。对筛查发现的癌症及后续癌症的基线乳腺钼靶片进行CAD评估。如果CAD正确提示，显著微小征象和假阴性被视为“可采取行动的”且可能可诊断。
CAD正确标记了筛查发现癌症的基线乳腺钼靶片的94%（98/104）（SFM = 95%[61/64]；FFDM = 93%[37/40]），包括96%（23/24）解释不一致的病例。仅考虑那些后续癌症的基线检查，前瞻性解释为正常且回顾性分类为“可采取行动的”病例，基线筛查时CAD输入有可能将癌症检出率从0.43%提高到0.51%（P = 0.13）；并使癌症检出增加16%（[104 + 17]/104），间期癌减少20%（从44例降至35例）。
在使用独立双重阅片和一致审查的SFM和FFDM筛查项目中，CAD可能有潜力使癌症检出增加高达16%，并使间期癌数量减少高达20%。然而，CAD真阳性和假阳性标记对决策的影响只能在一项前瞻性临床研究中进行评估。
