Interval breast cancer characteristics before, during and after the transition from screen-film to full-field digital screening mammography.

BACKGROUND: To determine the proportion of "true" interval cancers and tumor characteristics of interval breast cancers prior to, during and after the transition from screen-film mammography screening (SFM) to full-field digital mammography screening (FFDM). METHODS: We included all women with interval cancers detected between January 2006 and January 2014. Breast imaging reports, biopsy results and breast surgery reports of all women recalled at screening mammography and of all women with interval breast cancers were collected. Two experienced screening radiologists reviewed the diagnostic mammograms, on which the interval cancers were diagnosed, as well as the prior screening mammograms and determined whether or not the interval cancer had been missed on the most recent screening mammogram. If not missed, the cancer was considered an occult ("true") interval cancer. RESULTS: A total of 442 interval cancers had been diagnosed, of which 144 at SFM with a prior SFM (SFM-SFM), 159 at FFDM with a prior SFM (FFDM-SFM) and 139 at FFDM with a prior FFDM (FFDM-FFDM). The transition from SFM to FFDM screening resulted in the diagnosis of more occult ("true") interval cancers at FFDM-SFM than at SFM-SFM (65.4% (104/159) versus 49.3% (71/144), P < 0.01), but this increase was no longer statistically significant in women who had been screened digitally for the second time (57.6% (80/139) at FFDM-FFDM versus 49.3% (71/144) at SFM-SFM). Tumor characteristics were comparable for the three interval cancer cohorts, except of a lower porportion (75.7 and 78.0% versus 67.2% af FFDM-FFDM, P < 0.05) of invasive ductal cancers at FFDM with prior FFDM. CONCLUSIONS: An increase in the proportion of occult interval cancers is observed during the transition from SFM to FFDM screening mammography. However, this increase seems temporary and is no longer detectable after the second round of digital screening. Tumor characteristics and type of surgery are comparable for interval cancers detected prior to, during and after the transition from SFM to FFDM screening mammography, except of a lower proportion of invasive ductal cancers after the transition.

Characteristics and prognosis of interval cancers after biennial screen-film or full-field digital screening mammography.

We determined the characteristics and prognosis of interval breast cancers (IC) at screen-film (SFM) and full-field digital (FFDM) screening mammography. The study population consisted of 417,746 consecutive screening mammograms (302,699 SFM screens and 115,047 FFDM screens), obtained between 2000 and 2011. During 2-year follow-up, we collected breast imaging reports, surgical reports, and pathology results. A total of 800 ICs had been diagnosed in the screened population, of which 288 detected in the first year (early ICs) and 512 in the second year (late ICs) after a negative screen. 31.3 % of early IC's and 19.1 % of late IC's, respectively, were visible in retrospect on the latest previous screens, but had been missed during screening (P < 0.001). Missed invasive ICs were larger (28.5 mm vs. 23.9 mm, P = 0.003) and showed a higher fraction of T3+cancers (16.9 vs. 8.5 %, P = 0.02) than true ICs (i.e., not visible at the latest screen). A higher portion of missed than true ICs underwent mastectomy (44.7 vs. 30.8 %, P = 0.002). We found no differences in mammographic and tumor characteristics for early ICs, detected either after SFM or FFDM. Late ICs following FFDM were more often true ICs than missed ICs (69.0 vs. 57.6 %, P = 0.03) and more often receptor triple negative (P = 0.02), compared to late ICs at SFM. Interval cancer subgroups showed comparable overall survival. Interval cancer subgroups show distinctive mammographic and tumor characteristics but a comparable overall survival.

Type and Extent of Surgery for Screen-Detected and Interval Cancers at Blinded Versus Nonblinded Double-Reading in a Population-Based Screening Mammography Program.

BACKGROUND: This study aimed to compare the type and extent of surgery in patients with screen-detected and interval cancers after blinded or nonblinded double-reading of screening mammograms. METHODS: The study investigated a consecutive series of screens double-read in either a blinded (n = 44,491) or nonblinded (n = 42,996) fashion between 2009 and 2011. During a 2 year follow-up period, the radiology reports, surgical correspondence, and pathology reports of all the screen-detected and interval cancers were collected. RESULTS: Screen-detected breast cancer was diagnosed for 325 women at blinded and 284 women at nonblinded double-reading. The majority of the women were treated by breast-conserving surgery (BCS) at both reading strategies (78.2 vs. 81.7 %; p = 0.51). Larger total resection volumes were observed at BCS for ductal carcinoma in situ (DCIS) treatment for patients after blinded double-reading (p = 0.005). The proportions of positive resection margins after BCS were comparable for patients with DCIS (p = 0.81) or invasive screen-detected cancers (p = 0.38) for the two reading strategies. A total of 158 interval cancers were diagnosed. The proportions of patients treated with BCS were comparable for the two reading strategies (p = 0.42). The total resection volume (p = 0.13) and the proportion of positive resection margins after BCS (p = 0.32) for invasive interval cancer were comparable for the two cohorts. The BCS rate was higher for women after nonblinded double-reading (p = 0.04). CONCLUSIONS: Blinded and nonblinded double-reading yielded comparable surgical treatments for women with screen-detected or interval breast cancer except for larger total resection volumes at BCS for screen-detected DCIS and a higher BCS rate for interval cancers at nonblinded double-reading.

Oncologic outcomes of de-escalating axillary treatment in clinically node-positive breast cancer patients treated with neoadjuvant systemic therapy - A two center cohort study.

BACKGROUND: The aim of the present study was to report the 5-year axillary recurrence-free interval (aRFI) in clinically node-positive breast cancer patients treated according to a de-escalating axillary treatment protocol after neoadjuvant systemic therapy (NST). METHODS: All patients diagnosed in two hospitals between October 2014 and March 2021 were identified retrospectively. Data on diagnostic workup, treatment and follow-up was collected. Adjuvant axillary treatment was considered based on the initial staging using 18F-FDG PET/CT and the results of axillary lymph node marking with a radioactive-iodine seed protocol or a targeted axillary dissection procedure. Follow-up was updated until 27th April 2024. Kaplan-Meier curves were calculated to report the 5-year aRFI with corresponding 95 % confident intervals (95%-CI). RESULTS: A total of 199 patients were included. Axillary pathological complete response was reported in 66 (33.2 %). Based on the treatment protocol and initial clinical staging, no adjuvant axillary treatment was indicated in 30 patients (15 %), while 139 (70 %) received axillary radiotherapy without performance of an axillary lymph node dissection (ALND). The remaining 30 patients (15 %) underwent an ALND with additional locoregional radiotherapy. A median follow-up of 62 months (30-106) showed that 4 (2 %) patients experienced an axillary recurrence after 7, 8, 36 and 36 months, respectively. In all 4 patients, synchronous distant metastases were diagnosed. The estimated 5-year aRFI was 97.8 % (95%-CI 95.6-99.9 %) CONCLUSION: Although longer follow-up should be awaited before final conclusions can be drawn regarding the oncological safety of this approach, the implementation of a de-escalating axillary treatment protocol appears to be safe since the estimated 5-year aRFI is 97.8 %.

Trends in the pre-operative diagnosis and surgical management of axillary lymph node metastases in women with screen-detected breast cancer.

AIM: The aim of the current study was to investigate time-trends in pre-operative diagnosis and surgical treatment of axillary lymph node metastases in breast cancers detected at screening mammography. METHODS: We included all women who underwent screening mammography in the South of the Netherlands between 2005 and 2020. During a follow-up period of at least two years, data on clinical radiological examinations, biopsy procedures and surgical interventions were obtained. The 15 years of inclusion were divided into five cohorts of three years each. RESULTS: Of the 4049 women with invasive breast cancer, 22.1 % (896/4049) had axillary lymph node metastasis at pathology (ALN+). Percutaneous axillary biopsy was performed in 39.6 % (355/896) of these women, with the proportions of fine needle aspiration biopsy (FNAB) decreasing from 97.6 % (40/41) in 2005-2007 to 41.6 % (37/89) in 2017-2019 and core needle biopsy (CNB) rising from 2.4 % (1/41) in 2005-2007 to 58.4 % (52/89) in 2017-2019 (P < 0.001). Sensitivity of FNAB and CNB was comparable (77.4 % (188/243, 95%CI = 71%-82 %) versus 82.4 % (103/125), 95%CI = 74%-88 %) (P = 0.26). Pre-operative confirmation of ALN + by percutaneous biopsy ranged from 27.3 % (56/205) in 2011-2013 to 39.0 % (80/205) in 2017-2019, with no significant trend changes over time (P = 0.103). The proportion of ALN + women who underwent axillary lymph node dissection (ALND) decreased from 96.0 % (97/101) in 2005-2007 to 16.6 % (34/205) in 2017-2019 (P < 0.001). CONCLUSION: Pre-operative confirmation of axillary lymph node metastasis by ultrasound-guided biopsy did not rise despite the increased use of CNB at the expense of less invasive FNAB. A significant reduction in ALND was observed through the years.

Incidence and tumour characteristics of bilateral and unilateral interval breast cancers at screening mammography.

BACKGROUND: Detected by screening mammography, bilateral breast cancer has a different pathological profile compared to unilateral breast cancer. We investigated the incidence of bilateral interval breast cancers and compared their characteristics with those of unilateral interval breast cancers. METHODS: We included all 468,720 screening mammograms of women who underwent biennial screening mammography in the South of the Netherlands between January 2005 and January 2015. We collected breast imaging reports, biopsy results and surgical reports of all referred women and of all women who presented with interval breast cancer. The tumour with the highest tumour stage (index cancer) was used for comparison with unilateral interval cancers. RESULTS: A total of 753 interval cancers were detected, of which 24 (3.2%) were bilateral. Among the invasive interval cancers, bilateral cancers more frequently showed a lobular histology than unilateral cancers (37.5% (9/24) vs. 16.1% (111/691), P = .01). There is a trend towards a larger proportion of bilateral than unilateral interval cancers graded 1 (45.8% (11/24) vs. 27.8% (192/691), P = .08). There were no other statistically significant differences in tumour characteristics. Also, the proportion of interval cancers showing significant mammographic abnormalities at the latest screen was comparable for unilateral and bilateral interval cancers (23.0% vs. 25.0%, P = .9). DISCUSSION: Bilateral interval cancers comprise a small proportion of all interval cancers. Except of a higher proportion of invasive lobular cancers and a more favourable histological grade of invasive cancers, tumour characteristics are comparable for bilateral and unilateral interval breast cancers.