Jacky Luiten

74 | Chapter 5 Outcome after recall Breast cancer was diagnosed in 4932 recalled women (screen‐detected cancers) and 1391 nonrecalled women (interval cancers), yielding an overall CDR of 6.0 per 1000 screening examinations (4932/817,656) (Table 5.1) and a program sensitivity of 78.0% (4932/6323). If the proportions reported earlier are translated into CDR, the rates for initial screening examinations increased from 6.4 per 1000 screening examinations (297/46,155) in the SFM period to 7.8 per 1000 screening examinations (323/41,204) in the FFDM period ( p =0.01) and the CDR for subsequent screening examinations increased from 4.8 per 1000 screening examinations (1477/304,854) to 6.8 per 1000 screening examinations (2264/335,315), respectively ( p< 0.001). Similarly, although the recall rate of suspicious microcalcifications increased from 2.1 per 1000 screening examinations (741/351,009) in the SFM period to 5.7 per 1000 screening examinations (2162/376,519) in the FFDM period ( p< 0.001), the DCIS detection rate increased from 0.9 per 1000 screening examinations (321/351,009) to 1.7 per 1000 screening examinations (637/376,519; p<0.001), respectively (Figure 5.2). In 2009‐2010, an increased recall rate for suspicious microcalcifications to 7.2 per 1000 screening examinations (653/90,128; p <0.001 vs. the SFM period) was observed, as well as an increase in the DCIS detection rate to 1.7 per 1000 screening examinations (153/90,128; p <0.001 vs. the SFM period). These changes were temporally associated with the introduction of digital mammography. To more closely assess the change in the DCIS detection rate given the apparent shift after the introduction of FFDM, a chi‐square test comparing detection rates during the SFM period and FFDM period showed that detection rates significantly increased after the introduction of FFDM ( p <0.001 for both initial and subsequent screening examinations). The PPV for overall recall was 26.5% (4932/18,592). Table 5.1 shows the PPVs and 95% CIs for all recalls and for initial and subsequent screening examinations. The PPV for all recalls decreased from 41.8% (224/536) in 1997‐1998 to 24.5% (887/3621) in 2015‐2016. In the comparison of the SFM and the FFDM periods, the PPV for all recalls decreased from 39.8% (1774/4452) to 22.0% (2587/11,781) ( p <0.001). As shown in Figure 5.3, the PPV for microcalcification recalls showed a similar decreasing trend over the years, from 51.0% (26/51) in 1997‐1998 to 32.6% (222/680) in 2015‐2016 (43.3%; 321/741 during the SFM period vs. 29.5% 637/2162 during the FFDM period; p <0.001).