Initial experience of magnetic seed localization for impalpable breast lesion excision: First 100 cases performed in a single Irish tertiary referral centre.

INTRODUCTION: Wire guided localization has been widely utilized as the standard method of pre-operative localization of breast lesions. Magnetic seeds were developed to counter some of the disadvantages associated with wires. This aim of this study was to assess outcomes following the introduction of magnetic seeds at a tertiary specialist breast centre. METHODS: A retrospective review of a prospective database of the first 100 patients who underwent magnetic seed (Magseed) guided breast surgery between November 2018 and November 2019. Data was collected from 17 wire guided cases completed during the trial phase for comparison. The primary outcome measures were successful excision of index lesion and retrieval of the magnetic seed. Secondary outcomes analyzed included time ready for theatre, post-operative complications and breast margin re-excision rate. RESULTS: Of these 100 cases, 85 patients underwent Magseed guided wide local excision for invasive or in-situ carcinoma and 15 underwent Magseed guided diagnostic excision. The primary lesion was excised, and Magseed was retrieved in all 100 cases. 54% of patients were ready to proceed as the first scheduled theatre case of the day, compared to 0% of wire-guided cases. Amongst therapeutic Magseed guided cases, the re-excision rate for margin clearance was 9.4%. CONCLUSION: Magseed guided breast excision is a new technology that has been implemented with relative ease in our unit. We have shown that magnetic seed guided surgery reliably localizes lesions, is associated with low re-excision rates without an increase in patient morbidity or mortality and results in improvements in theatre planning and efficiency.

Lobular intraepithelial neoplasia: Outcomes and optimal management.

INTRODUCTION: Lobular neoplasia is a term encompassing both atypical lobular hyperplasia and lobular carcinoma in situ. These pathological findings are of uncertain malignant potential and predispose to a higher lifetime risk of breast cancer. Debate surrounds the management of such lesions, with the rationale for diagnostic excision based on the possibility of upgrading to malignancy. In this study, we report the upgrade rate of these lesions and risk of subsequent development of breast cancer. METHODS: This is a retrospective review of a prospectively maintained data base of all biopsies of breast screening-detected abnormalities in a single Irish breast-screening unit. We included all patients with lobular neoplasia on core needle biopsy who underwent diagnostic excision from 2005 to 2012. We excluded those who had concurrent high-risk lesions on biopsy. End points included upgrade rate and subsequent diagnosis of malignancy on follow-up. RESULTS: During the study period, 66 patients met criteria for inclusion, with a mean age of 53.74 years. Upgrade rate following excision was 13.64% (n = 9/66). Of those not upgraded, 7.02% (n = 4/57) were subsequently diagnosed with malignancy. Median time to diagnosis was 59.61 months (range = 10.5-124.4). CONCLUSION: There is a significant rate of upgrade following diagnostic excision of lobular neoplasia, supporting the practice of diagnostic excision. There is an increased lifetime risk of breast cancer for women with a diagnosis of lobular neoplasia, with many of these cancers occurring outside the standard five-year monitoring period, suggesting a potential benefit in extending surveillance.

Examining the impact of COVID-19 disruptions on population-based breast cancer screening in Ireland.

OBJECTIVE: Many population-based breast screening programmes temporarily suspended routine screening following the COVID-19 pandemic onset. This study aimed to describe screening mammography utilisation and the pattern of screen-detected breast cancer diagnoses following COVID-19-related screening disruptions in Ireland. METHODS: Using anonymous aggregate data from women invited for routine screening, three time periods were examined: (1) January-December 2019, (2) January-December 2020, and (3) January-December 2021. Descriptive statistics were conducted and comparisons between groups were performed using chi-square tests. RESULTS: In 2020, screening mammography capacity fell by 67.1% compared to 2019; recovering to 75% of mammograms performed in 2019, during 2021. Compared to 2019, for screen-detected invasive breast cancers, a reduction in Grade 1 (14.2% vs. 17.2%) and Grade 2 tumours (53.4% vs. 58.0%) and an increase in Grade 3 tumours (32.4% vs. 24.8%) was observed in 2020 (p = 0.03); whereas an increase in Grade 2 tumours (63.3% vs. 58.0%) and a reduction in Grade 3 tumours (19.6% vs. 24.8%) was found in 2021 (p = 0.02). No changes in oestrogen receptor-positive or nodal-positive diagnoses were observed; however the proportion of oestrogen/progesterone receptor-positive breast cancers significantly increased in 2020 (76.2%; p < 0.01) and 2021 (78.7%; p < 0.001) compared to 2019 (67.8%). CONCLUSION: These findings demonstrate signs of a grade change for screen-detected invasive breast cancers early in the pandemic, with recovery evident in 2021, and without an increase in nodal positivity. Future studies are needed to determine the COVID-19 impact on long-term breast cancer outcomes including mortality.

Interval cancer audit and disclosure in breast screening programmes: An international survey.

OBJECTIVE AND SETTING: Accurate monitoring of interval cancers is important both for quality improvement and education and is a key parameter of breast screening quality assurance. Issues in relation to communication regarding interval cervical cancer in the Irish cervical screening programme were found, prompting interval cancer process review in all cancer screening programmes. An international survey to examine international consensus on interval breast cancer audit processes was conducted to inform Irish processes. METHODS: A survey of 24 international population-based breast screening programmes was done to determine which undertook audit of interval breast cancer; if yes, they were asked (1) how they undertake audit, (2) if they obtain individual consent for audit and inform women of audit results, and (3) if disclosure of audit results occurs. RESULTS: Response was 71% (17/24). Of these, 71% (12/17) have a programmatic audit process to calculate the interval cancer rate (ICR). Of these, ten also carry out radiological reviews, three using a blinded review. Two inform patients that audit is taking place; two provide choice to be in the audit; nine state that routine screening consent covers audit. For two of the five that have an open disclosure policy for medical incidents, this policy applies to screening interval cancers. One other country/region has an open disclosure policy for category 3 interval cancers only. Five have legal protection for interval cancers arising in the screened population. CONCLUSION: While consistency in providing aggregate programmatic audits exists, there is no consistent approach to individual interval cancer reviews or results disclosure.

A scoping review of programme specific mammographic breast density related guidelines and practices within breast screening programmes.

Introduction: High mammographic breast density (MBD) is an independent breast cancer risk factor. In organised breast screening settings, discussions are ongoing regarding the optimal clinical role of MBD to help guide screening decisions. The aim of this scoping review was to provide an overview of current practices incorporating MBD within population-based breast screening programmes and from professional organisations internationally. Methods: This scoping review was conducted in accordance with the framework proposed by the Joanna Briggs Institute. The electronic databases, MEDLINE (PubMed), EMBASE, CINAHL Plus, Scopus, and Web of Science were systematically searched. Grey literature sources, websites of international breast screening programmes, and relevant government organisations were searched to identify further relevant literature. Data from identified materials were extracted and presented as a narrative summary. Results: The search identified 78 relevant documents. Documents were identified for breast screening programmes in 18 countries relating to screening intervals for women with dense breasts, MBD measurement, reporting, notification, and guiding supplemental screening. Documents were identified from 18 international professional organisations with the majority of material relating to supplemental screening guidance for women with dense breasts. Key factors collated during the data extraction process as relevant considerations for MBD practices included the evidence base needed to inform decision-making processes and resources (healthcare system costs, radiology equipment, and workforce planning). Conclusions: This scoping review summarises current practices and guidelines incorporating MBD in international population-based breast screening settings and highlights the absence of consensus between organised breast screening programmes incorporating MBD in current breast screening protocols.

Screen-detected ductal carcinoma in situ, 2008-2020: An observational study.

OBJECTIVES: The purpose of this study was to evaluate the grade distribution of screen-detected ductal carcinoma in situ (DCIS) diagnosed in Ireland, in the context of the clinical trials currently underway to determine if active surveillance is a feasible management option for low-risk DCIS. SETTING: BreastCheck is the national breast screening programme in Ireland, offering screening to women aged 50 to 69 every two years. METHODS: This study was a secondary analysis of data collected by BreastCheck on all screen-detected DCIS diagnosed in the 12 years of nationwide screening. Incidence and detection rates were calculated. Descriptive analysis of the cases was performed and, for comparative analysis, grade of DCIS was analysed as a binary variable (high vs. low/intermediate) in keeping with the inclusion criteria for active surveillance trials. Analysis was performed in IBM Statistical Package for Social Sciences, version 26. RESULTS: Between 2008 and 2020, 2240 women were diagnosed with DCIS through BreastCheck; 876 (39.1%) were low/intermediate-grade. The overall incidence rate has remained relatively stable during this period. Women with low/intermediate-grade DCIS were younger than women with high-grade DCIS (56 (interquartile range: 56-61) years v 57 (interquartile range: 53-61) years; p < 0.001). They were also more likely to have been diagnosed at an initial screening episode compared with those who had high-grade lesions (42.5% v 29.0%; p < 0.001). CONCLUSION: If current clinical trials recommend active surveillance as a feasible option for DCIS, up to 40% of women with screen-detected DCIS may be eligible. These women are younger and often diagnosed on initial screening episode, so may require longer active follow-up.

Retrospective radiological review and classification of interval breast cancers within population-based breast screening programmes for the purposes of open disclosure: A systematic review.

INTRODUCTION: Interval breast cancers occur following a negative breast screening mammogram and before the next scheduled appointment within screening programmes. Radiological review classifies them as cancers that develop between screens, cancers with no obvious malignant abnormalities on prior screens or cancers not detected at screening. This study aimed to systematically review published literature on the occurrence of open disclosure following interval cancer radiological reviews by breast screening programmes internationally in a retrospective setting and examine methodologies used for radiological reviews for the purposes of disclosure. METHODS: A search for relevant articles published (January 2000 - May 2019) was conducted according to PICO and PRISMA guidelines. The databases Pubmed, Scopus, Google Scholar, Cinahl, Web of Science, Embase, Science Direct and Global Health were searched. Relevant studies were reviewed if they had completed a retrospective review and classification of interval breast cancers. RESULTS: Of 46 relevant articles included, no study was identified that conducted a retrospective review purposely for open disclosure. Retrospective reviews were conducted for audit/quality assurance, and research including for radiologist education and learning. Variation in methodology was found across review type (non-blinded/semi-informed approach), number of reviewers and classification categories. The proportion of false negative cancers classified among the studies ranged from 4 to 40 %. DISCUSSION: Variation among radiological review practices were observed, which likely impacts classification results. To ensure standardised classification of interval breast cancers are employed for the purposes of open disclosure in screening settings, reproducible and consistent methodology is required.

Upgrade rates and outcomes of screen-detected atypical intraductal epithelial proliferation (AIDEP) diagnosed on core needle biopsy.

INTRODUCTION: Atypical intraductal epithelial proliferation (AIDEP) is a breast lesion categorised as "indeterminate" if identified on core needle biopsy (CNB). The rate at which these lesions are upgraded following diagnostic excision varies in the literature. Women diagnosed with AIDEP are thought to be at increased risk of breast cancer. Our aim was to identify the rate of upgrade to invasive or in situ carcinoma in a group of patients diagnosed with AIDEP on screening mammography and to quantify their risk of subsequent breast cancer. METHODS: We conducted a retrospective review of a prospectively maintained database containing all patients diagnosed with AIDEP on CNB between 2005 and 2012 in an Irish breast screening centre. Basic demographic data was collected along with details of the original CNB result, rate of upgrade to carcinoma and details of any subsequent cancer diagnoses. RESULTS: In total 113 patients were diagnosed with AIDEP on CNB during the study period. The upgrade rate on diagnostic excision was 28.3% (n = 32). 6.2% (n = 7) were upgraded to invasive cancer and 22.1% (n = 25) to DCIS. 81 patients were not upgraded on diagnostic excision and were offered 5 years of annual mammographic surveillance. 9.88% (8/81) of these patients went on to receive a subsequent diagnosis of malignancy. The mean time to diagnosis of these subsequent cancers was 65.41 months (range 20.18-145.21). CONCLUSION: Our data showing an upgrade rate of 28% to carcinoma reflects recently published data and we believe it supports the continued practice of excising AIDEP to exclude co-existing carcinoma.

Comparison of digital mammography and screen-film mammography in breast cancer screening: a review in the Irish breast screening program.

OBJECTIVE: Clinical trials to date into the use of full-field digital mammography (FFDM) for breast cancer screening have shown variable results. The aim of this study was to review the use of FFDM in a population-based breast cancer screening program and to compare the results with screen-film mammography. MATERIALS AND METHODS: The study included 188,823 screening examinations of women between 50 and 64 years old; 35,204 (18.6%) mammograms were obtained using FFDM. All films were double read using a 5-point rating scale to indicate the probability of cancer. Patients with positive scores were recalled for further workup. The recall rate, cancer detection rate, and positive predictive value (PPV) of FFDM were compared with screen-film mammography. RESULTS: The cancer detection rate was significantly higher for FFDM than screen-film mammography (6.3 vs 5.2 per 1,000, respectively; p = 0.01). The cancer detection rate for FFDM was higher than screen-film mammography for initial screening and subsequent screening, for invasive cancer and ductal carcinoma in situ, and across all age groups. The cancer detection rate for cancers presenting as microcalcifications was significantly higher for FFDM than for screen-film mammography (1.9 vs 1.3 per 1,000, p = 0.01). The recall rate was significantly higher for FFDM than screen-film mammography (4.0% vs 3.1%, p < 0.001). There was no significant difference in the PPVs of recall to assessment for FFDM and screen-film mammography (15.7% and 16.7%, p = 0.383). CONCLUSION: FFDM resulted in significantly higher cancer detection and recall rates than screen-film mammography in women 50-64 years old. The PPVs of FFDM and screen-film mammography were comparable. The results of this study suggest that FFDM can be safely implemented in breast cancer screening programs.

Evolution of the National Breast Screening Programme in Ireland: Two-year interval analysis (2004-2013) of BreastCheck.

OBJECTIVE: Monitoring breast screening programmes is essential to ensure quality. BreastCheck, the national breast screening programme in the Republic of Ireland, commenced screening in 2000, with full national expansion in 2007, and digital mammography introduced in 2008. We aimed to review the performance of BreastCheck from 1 January 2004 to 31 December 2013. METHODS: Using the customised clinical and administrative database, performance indicator data were collected from BreastCheck and compared with programme and European guideline standards. RESULTS: Over the decade, 972,236 screening examinations were performed. Uptake initially rose following national expansion, but fell in the subsequent years to <70% in 2012-2013. Following the introduction of digital mammography, initial recall rates increased from 5.2% in 2004-2005 to 8.1% in 2012-2013. Subsequent recall rates remained within the target of <3%. On average, invasive cancer detection rates were 6.6/1000 for initial and 4.5/1000 for subsequent women. Small cancer detection rates were for <15 mm 43.4% (initial women) and 51.7% (subsequent) and for ≤10 mm 24.0% (initial) and 29.5% (subsequent). Ductal carcinoma in situ detection as a percentage of all cancers averaged 21.2% for initial and 20.0% for subsequent women. The majority were intermediate or high-grade ductal carcinoma in situ. The positive predictive value was 11.9% for initial and 21.8% for subsequent women. Standardized detection ratios remained above the programme target. CONCLUSION: Revised indicators to reflect the digital mammography era are anticipated in revised European Guidelines on breast cancer screening.

Impact of full field digital mammography on the classification and mammographic characteristics of interval breast cancers.

OBJECTIVE: Full field digital mammography (FFDM) is increasingly replacing screen film mammography (SFM) in breast screening programs. Interval breast cancers are an issue in all screening programs and the purpose of our study is to assess the impact of FFDM on the classification of interval breast cancers at independent blind review and to compare the mammographic features of interval cancers at FFDM and SFM. MATERIALS AND METHODS: This study included 138 cases of interval breast cancer, 76 following an FFDM screening examination and 62 following screening with SFM. The prior screening mammogram was assessed by each of five consultant breast radiologists who were blinded to the site of subsequent cancer. Subsequent review of the diagnostic mammogram was performed and cases were classified as missed, minimal signs, occult or true interval. Mammographic features of the interval cancer at diagnosis and any abnormality identified on the prior screening mammogram were recorded. RESULTS: The percentages of cancers classified as missed at FFDM and SFM did not differ significantly, 10.5% (8 of 76) at FFDM and 8.1% (5 of 62) at SFM (p=.77). There were significantly less interval cancers presenting as microcalcifications (alone or in association with another abnormality) following screening with FFDM, 16% (12 of 76) than following a SFM examination, 32% (20 of 62) (p=.02). CONCLUSION: Interval breast cancers continue to pose a problem at FFDM. The switch to FFDM has changed the mammographic presentation of interval breast cancer, with less interval cancers presenting in association with microcalcifications.

Digital mammography in a screening programme and its implications for pathology: a comparative study.

AIMS: Most studies comparing full-field digital mammography (FFDM) with conventional screen-film mammography (SFM) have been radiology-based. The pathological implications of FFDM have received little attention in the literature, especially in the context of screening programmes. The primary objective of this retrospective study is to compare FFDM with SFM in a population-based screening programme with regard to a number of pathological parameters. METHODS: During the study period, 107 818 women underwent screening mammograms with almost equal numbers obtained with each technique (49.9% with SFM vs 50.1% with FFDM). We compared SFM with FFDM using the following parameters: recall rate, diagnostic core biopsy rate, cancer detection rates, B3 rate, B4 rate, preoperative diagnostic rate for malignancy, positive predictive values and tumour characteristics. RESULTS: The recall rate was significantly higher with FFDM (4.21% vs 3.52%, p<0.0001). The overall cancer detection rate of 7.2 per 1000 women screened with FFDM was also significantly higher than the rate of 6.2 per 1000 women screened with SFM (p=0.04). The B3 rate in the SFM group was 1.3 per 1000 women screened versus 2.5 per 1000 women screened in the FFDM group (p<0.001). The recall rate and cancer detection rates (overall, invasive and pure ductal carcinoma in situ) were all significantly higher with FFDM for lesions presenting as microcalcifications. CONCLUSIONS: The higher cancer detection rate with FFDM in this study was due to improved detection of microcalcifications. However, this was achieved at the cost of a higher recall rate and a higher B3 rate, indicating that overtreatment may be problematic with digital mammography.

Axillary fine needle aspiration cytology for pre-operative staging of patients with screen-detected invasive breast carcinoma.

INTRODUCTION: Fine needle aspiration cytology (FNAC) of radiologically abnormal axillary lymph nodes in patients with breast cancer can identify patients suitable for primary axillary clearance (AC) rather than sentinel node biopsy, enabling surgical axillary staging by a single operation. This study assessed the accuracy of FNAC in predicting positive axillary lymph nodes. METHODS: 161 patients with screen-detected invasive carcinoma and who had pre-operative FNAC of a radiologically abnormal axillary lymph node were identified from two screening units, The axillary FNAC reports were correlated with sentinel node biopsy and AC reports, and sensitivity, specificity, positive (PPV) and negative (NPV) predictive values were calculated. RESULTS: FNAC had a moderate sensitivity (66.3%) and NPV (71.8%), and a high specificity (98.7%) and PPV (98.3%). Most patients (86%) had a single axillary operation. The sensitivity was highest in grade 3 (81.8%) and ductal type (77.8%) tumours. The sensitivity was lower in tumours of special type (34.8%), grade 1 tumours (50%) and those without lymphovascular invasion (LVI) (55.9%). The NPV was highest in pT1 (86.7%) and in grade 1 (84.5%) tumours, and lowest (44%) in tumours with LVI. The PPV was 100% in grade 1 and 3 tumours, stage pT2 and pT3 tumours and those without LVI, and was high (>96%) in all other groups. In lymph-node-positive patients, the mean number of lymph nodes involved was higher in the case of a positive (6.4) than negative FNAC (4.4). CONCLUSIONS: FNAC of ultrasonically abnormal axillary lymph nodes achieved surgical staging by a single operation in most patients with screen-detected invasive breast carcinoma, with moderate sensitivity and high specificity.

Role of sentinel lymph node biopsy in high-risk ductal carcinoma in situ patients.

BACKGROUND: The role of sentinel lymph node biopsy (SLNB) for ductal carcinoma in situ (DCIS) is poorly defined. However, up to 20% of patients with DCIS will have invasive carcinoma; these patients require staging for axillary metastasis. The aim of this study was to identify patients with a core biopsy diagnosis of DCIS who may benefit from SLNB. METHODS: In a prospective study, we performed SLNB on patients with a preoperative diagnosis of >2.5 cm of high-grade DCIS or DCIS when mastectomy was indicated. RESULTS: Sixty-two patients underwent surgery for high-grade DCIS, and 35 of these patients underwent SLNB. Postsurgical excision histology revealed invasive disease in 20 patients, 19 of whom had undergone SLNB. Before the adoption of SLNB in selected DCIS patients, all 20 with occult invasive disease would have required second surgery axillary staging (P < .01, chi-square test). CONCLUSIONS: SLNB should not be performed routinely for all patients with an initial diagnosis of DCIS. However, selective lymphadenectomy may be a useful clinical adjuvant in selected high-risk DCIS patients.