Patterns of treatment and outcome of ductal carcinoma in situ in the Netherlands.

PURPOSE: To spare DCIS patients from overtreatment, treatment de-escalated over the years. This study evaluates the influence of these developments on the patterns of care in the treatment of DCIS with particular interest in the use of breast conserving surgery (BCS), radiotherapy following BCS and the use and type of axillary staging. METHODS: In this large population-based cohort study all women, aged 50-74 years diagnosed with DCIS from January 1989 until January 2019, were analyzed per two-year cohort. RESULTS: A total of 30,417 women were diagnosed with DCIS. The proportion of patients undergoing BCS increased from 47.7% in 1995-1996 to 72.7% in 2017-2018 (p < 0.001). Adjuvant radiotherapy following BCS increased from 28.9% (1995-1996) to 89.6% (2011-2012) and subsequently decreased to 74.9% (2017-2018; p < 0.001). Since its introduction, the use of sentinel lymph node biopsy (SLNB) increased to 63.1% in 2013-2014 and subsequently decreased to 52.8% in 2017-2018 (p < 0.001). Axillary surgery is already omitted in 55.8% of the patients undergoing BCS nowadays. The five-year invasive relapse-free survival (iRFS) for BCS with adjuvant radiotherapy in the period 1989-2010, was 98.7% [CI 98.4% - 99.0%], compared to 95.0% [CI 94.1% -95.8%] for BCS only (p < 0.001). In 2011-2018, this was 99.3% [CI 99.1% - 99.5%] and 98.8% [CI 98.2% - 99.4%] respectively (p = 0.01). CONCLUSIONS: This study shows a shift toward less extensive treatment. DCIS is increasingly treated with BCS and less often followed by additional radiotherapy. The absence of radiotherapy still results in excellent iRFS. Axillary surgery is increasingly omitted in DCIS patients.

Recall and Outcome of Screen-detected Microcalcifications during 2 Decades of Mammography Screening in the Netherlands National Breast Screening Program.

Background Trends in the detection of suspicious microcalcifications at mammography screening and the yield of these lesions after recall are unknown. Purpose To determine trends in recall and outcome of screen-detected microcalcifications during 20 years of mammography screening. Materials and Methods The authors performed a retrospective analysis of a consecutive series of 817 656 screening examinations (January 1997 to January 2017) in a national breast screening program. In 2009-2010 (transition period), screen-film mammography (SFM) was gradually replaced by full-field digital mammography (FFDM). The recalls of suspicious microcalcifications from all radiology reports and pathologic outcome of recalled women with 2-year follow-up were analyzed. Screening outcome in the era of SFM (1997-2008), the transition period (2009-2010), and the era of FFDM (2011-2016) were compared. Trends over time and variations between the SFM and FFDM periods were expressed by using proportions with 95% confidence intervals (CIs). In cases where the analysis based on the CI confirmed clear periods (eg, before and after introduction of FFDM), pre- and postchange outcomes were compared by using χ2 tests. Results A total of 18 592 women (median age, 59 years; interquartile range, 14 years) were recalled at mammography screening, 3556 of whom had suspicious microcalcifications. The recall rate for microcalcifications increased from 0.1% in 1997-1998 to 0.5% in 2015-2016 (P < .001). This was temporally associated with the change from SFM to FFDM. The recalls yielding ductal carcinoma in situ (DCIS) increased from 0.3 per 1000 screening examinations with SFM to 1.1 per 1000 screening examinations with FFDM (P < .001), resulting in a decrease in the positive predictive value for recall for suspicious microcalcifications from 51% to 33% (P < .001). More than half of all DCIS lesions were high grade (52.6%; 393 of 747). The distribution of DCIS grades was stable during the 20-year screening period (P = .36). Conclusion The recall rate for suspicious microcalcifications at mammographic screening increased during the past 2 decades, whereas the ductal carcinoma in situ detection rate increased less rapidly, resulting in a lower positive predictive value for recall. © RSNA, 2020.

Utility of diagnostic breast excision biopsies during two decades of screening mammography.

INTRODUCTION: We evaluated the use and value of breast surgical excision biopsies for diagnostic purposes over the last decades in women undergoing mammographic screening, either as a primary procedure or following an inconclusive percutaneous biopsy. METHODS: All women with an excision biopsy among 817,656 screens, obtained from January 1997 to January 2017, were included. RESULTS: Of 18,593 recalled women (recall rate, 2.3%) with screen-detected abnormalities, 908 (4.9%) underwent excision biopsy. Of these, 411 (45.3%) were performed as first diagnostic intervention, decreasing from 4.3 per 1000 screens in 1997-1998 to 0 per 1000 screens in 2015-2016. The remaining 497 (54.7%) excision biopsies were performed secondary to pathologic findings at percutaneous biopsy. During 1997-1998, 1.0 secondary biopsies per 1000 screens were performed, decreasing to 0.3 per 1000 in 2005-2006 and afterwards increased to 0.6 per 1000 in 2015-2016 (p = 0.003). Of all 487 secondary biopsies, 303 (61.0%) had a benign pathology outcome, increasing from 40.4% in 1997-1998 to 70.2% in 2015-2016. Of all 211 biopsies in the three most recent cohorts (2011-2016) the overall upgrade rate was 26.5%, consisting of 39 (18.5%) DCIS (27 low grade) and 17 (8.1%) invasive carcinomas. CONCLUSIONS: Although the use of excision biopsy significantly decreased over the past two decades, we observed a significant increased rate in more recent years. Since the vast majority of currently performed excision biopsies reveals a benign diagnosis or shows low grade DCIS, a secondary excision biopsy should only be considered if radiologic surveillance and repeated percutaneous biopsy continues to yield indeterminate results.

Trends in frequency and outcome of high-risk breast lesions at core needle biopsy in women recalled at biennial screening mammography, a multiinstitutional study.

Between January 1, 2011, and December 31, 2016, we studied the incidence, management and outcome of high-risk breast lesions in a consecutive series of 376,519 screens of women who received biennial screening mammography. During the 6-year period covered by the study, the proportion of women who underwent core needle biopsy (CNB) after recall remained fairly stable, ranging from 39.2% to 48.1% (mean: 44.2%, 5,212/11,783), whereas the proportion of high-risk lesions at CNB (i.e., flat epithelial atypia, atypical ductal hyperplasia, lobular carcinoma in situ and papillary lesions) gradually increased from 3.2% (25/775) in 2011 to 9.5% (86/901) in 2016 (p < 0.001). The mean proportion of high-risk lesions at CNB that were subsequently treated with diagnostic surgical excision was 51.4% (169/329) and varied between 41.0% and 64.3% through the years, but the excision rate for high-risk lesions per 1,000 screens and per 100 recalls increased from 0.25 (2011) to 0.70 (2016; p < 0.001) and from 0.81 (2011) to 2.50 (2016; p < 0.001), respectively. The proportion of all diagnostic surgical excisions showing in situ or invasive breast cancer was 29.0% (49/169) and varied from 22.2% (8/36) in 2014 to 38.5% (5/13) in 2011. In conclusion, the proportion of high-risk lesions at CNB tripled in a 6-year period, with a concomitant increased excision rate for these lesions. As the proportion of surgical excisions showing in situ or invasive breast cancer did not increase, a rising number of screened women underwent invasive surgical excision with benign outcome.

Trends in incidence and tumour grade in screen-detected ductal carcinoma in situ and invasive breast cancer.

PURPOSE: In a biennial screening mammography programme, we analysed the trends in incidence of screen-detected DCIS and invasive breast cancers in the era of screen-film mammography (SFM) screening, the period of the transition to full-field digital mammography (FFDM) screening and the period of FFDM screening. We also investigated a possible association between the incidence and grading of screen-detected DCIS and invasive breast cancer. METHODS: In the southern part of the Netherlands, FFDM screening gradually replaced SFM screening between May 2009 and April 2010. We included a consecutive series of 484, 422 screens obtained between July 2005 and July 2015 and divided these screens into three groups; SFM-only cohort, transition cohort and FFDM-only cohort. RESULTS: A total of 3059 referred women were diagnosed with DCIS (n = 623) or invasive breast cancer (n = 2436). The majority of DCIS were high-grade (48.2%), whereas the majority of the invasive breast cancers were low-grade (45.4%) or intermediate-grade (41.6%). The cancer detection rate (CDR) per 1000 screened women showed the same distribution by grade in both groups. The transition to FFDM was characterised by an increased overall detection rate of invasive cancers. CONCLUSIONS: Screening mammography detects mostly high-grade DCIS and low- or intermediate-grade invasive cancers. The grade distribution as well as the CDR in the years after the introduction of FFDM remained stable compared to the era of SFM screening. By diagnosing and treating high-grade DCIS, which otherwise may develop into high-grade invasive carcinoma, our findings provide new evidence for the beneficial value of screening mammography programmes.