Reduction in advanced breast cancer after introduction of a mammography screening program in Tyrol/Austria

BackgroundWe analysed all female breast cancer (BC) cases in Tyrol/Austria regarding the shift in cancer characteristics, especially the shift in advanced BC, for the group exposed to screening as compared to the group unexposed to screening.MethodsThe analysis was based on all BC cases diagnosed in women aged 40–69 years, resident in Tyrol, and diagnosed between 2009 and 2013. The data were linked to the Tyrolean mammography screening programme database to classify BC cases as “exposed to screening” or “unexposed to screening”. Age-adjusted relative risks (RR) were estimated by relating the exposed to the unexposed group.ResultsIn a total of about 145,000 women aged 40–69 years living in Tyrol during the study period, 1475 invasive BC cases were registered. We estimated an age-adjusted relative risk (RR) for tumour size ≥ 21 mm of 0.72 (95% confidence interval (CI) 0.60 to 0.86), for metastatic BC of 0.27 (95% CI 0.17 to 0.46) and for advanced BC of 0.83 (95% CI 0.71 to 0.96), each comparing those exposed to those unexposed to screening, respectively.ConclusionIn our population-based registry analysis we observed that participation in the mammography screening programme in Tyrol is associated with a 28% decrease in risk for BC cases with tumour size ≥ 21 mm and a 17% decrease in risk for advanced BC. We therefore expect the Tyrolean mammography programme to show a reduction in BC mortality.     

Overdiagnosis, sojourn time, and sensitivity in the Copenhagen mammography screening program

The goal of this research was to estimate the overdiagnosis at the first and second screens of the mammography screening program in Copenhagen, Denmark. This study involves a mammography service screening program in Copenhagen, Denmark, with 35,123 women screened at least once. We fit multistate models to the screening data, including preclinical incidence of progressive cancers and nonprogressive (i.e., overdiagnosed) cancers. We estimated mean sojourn time as 2.7 years (95% confidence interval [CI] 2.2-3.1) and screening test sensitivity as 100% (95% CI 99.8-100). Overdiagnosis was estimated to be 7.8% (95% CI 0.3-26.5) at the first screen and 0.5% (95% CI 0.02-2.1) at the second screen. This corresponds to 4.8% of all cancers diagnosed among participants during the first two invitation rounds and following intervals. A modest overdiagnosis was estimated for the Copenhagen screening program, deriving almost exclusively from the first screen. The CIs were very broad, however, and estimates from larger datasets are warranted.     

Irregular screening participation increases advanced stage breast cancer at diagnosis: A population-based study

ObjectiveTo evaluate the effect of irregular screening behaviour on the risk of advanced stage breast cancer at diagnosis in Flanders.MethodsAll women aged 50–69 who were invited to the organized breast cancer screening and diagnosed with breast cancer before age 72 from 2001 to 2018 were included. All prevalent screen and interval cancers within 2 years of a prevalent screen were excluded. Screening behaviour was categorized based on the number of invitations and performed screenings. Four groups were defined: regular, irregular, only-once, and never attenders. Advanced stage cancer was defined as a stage III + breast cancer. The association between screening regularity and breast cancer stage at diagnosis was evaluated in multivariable logistic regression models, taking age of diagnosis and socio-economic status into account.ResultsIn total 13.5% of the 38,005 breast cancer cases were diagnosed at the advanced stage. Compared to the regular attenders, the risk of advanced stage breast cancer for the irregular attenders, women who participated only-once, and never attenders was significantly higher with OR_adjusted:1.17 (95%CI:1.06–1.29) and OR_adjusted:2.18 (95%CI:1.94–2.45), and OR_adjusted:5.95 (95%CI:5.33–6.65), respectively.ConclusionsIn our study, never attenders were nearly six times more likely to be diagnosed with advanced stage breast cancer than regular attenders, which was much higher than the estimates published thus far. An explanation for this is that the ever screened women is a heterogeneous group regarding the participation profiles which also includes irregular and only-once attenders. The benefit of regular screening should be informed to all women invited for screening.     

Is There a Correlation Between Breast Cancer Molecular Subtype Using Receptors as Surrogates and Mammographic Appearance?

Background

The identification of distinct molecular subtypes has changed breast cancer management. The correlation between mammographic appearance and molecular subtype for invasive breast cancer has not been extensively studied.

Methods

A retrospective review of our prospectively collected database was performed to evaluate the mammographic appearance and molecular subtypes of all cases of invasive breast cancers diagnosed between 2003 and 2010.

Results

There were 985 cases of invasive breast cancer with complete data on receptor status and mammographic appearance. The most common mammographic finding was a mass (61 %), and the most common molecular subtype was ER/PR positive, HER2 negative (71 %). On univariate analysis, race, stage, and histology were all significantly associated with molecular subtype. On multivariate analysis, the luminal molecular type was associated with architectural distortion [odds ratio (OR) 4.3, 95 % CI 1.3–14.1]; HER2 positive cancers, either with or without ER/PR expression, were more likely to be associated with mammographic calcifications (OR 2.8 and 3.1, respectively; 95 % CI 1.7–4.8 and 1.7–5.5); and triple negative cancers were most likely to be associated with a mammographic mass (OR 2.5; 95 % CI 1.4–4.4).

Conclusions

We observed several characteristic associations between molecular subtype and mammographic appearance. Improved understanding of these associations may help guide clinical decision making and provide information about underlying tumor biology.     

The impact of organized breast assessment on survival by stage for screened women diagnosed with invasive breast cancer

PurposeSince 1998, the Ontario Breast Screening Program (OBSP) has offered organized assessment through Breast Assessment Centres (BAC). This study compares survival between screened women diagnosed with breast cancer who have undergone assessment through a BAC and usual care (UC).MethodsA retrospective design identified two concurrent cohorts of women aged 50 to 69 within the OBSP diagnosed with screen-detected invasive breast cancer at a BAC (n = 2010) and UC (n = 1844) between 2002 and 2010 and followed until 2016. Demographic and assessment characteristics were obtained from the OBSP. Abstraction of medical charts provided prognostic and treatment data. Death data were assessed from the Registered Person's Database and the Ontario Registrar General All-Cause Mortality File. Multivariable Cox proportional hazards models compared overall survival by assessment type (BAC/UC), stratified by stage.ResultsThere were 505 deaths during the study (BAC = 239; UC = 266). Among women with stage I screen-detected breast cancer, those diagnosed through a BAC had 31% reduced risk of all-cause mortality (HR = 0.69, 95% CI = 0.53–0.90) compared to UC. Diagnosis within 7 weeks of an abnormal mammogram reduced the hazard of death from all causes by 34% among all women with stage I breast cancers (HR = 0.66, 95% CI = 0.47–0.91), and was more likely in BAC (79.7%) than UC (66.9%).ConclusionThe significant improvement in overall survival for women with stage I screen-detected invasive breast cancer assessed through BACs further supports the recommendation that women with abnormal mammograms should be managed through organized assessment.     

Differences in breast cancer risk after benign breast disease by type of screening diagnosis

IntroductionWe aimed to assess differences in breast cancer risk across benign breast disease diagnosed at prevalent or incident screens.Materials and methodsWe conducted a retrospective cohort study with data from 629,087 women participating in a long-standing population-based breast cancer screening program in Spain. Each benign breast disease was classified as non-proliferative, proliferative without atypia, or proliferative with atypia, and whether it was diagnosed in a prevalent or incident screen. We used partly conditional Cox hazard regression to estimate the adjusted hazard ratios of the risk of breast cancer.ResultsCompared with women without benign breast disease, the risk of breast cancer was significantly higher (p-value = 0.005) in women with benign breast disease diagnosed in an incident screen (aHR, 2.67; 95%CI: 2.24–3.19) than in those with benign breast disease diagnosed in a prevalent screen (aHR, 1.87; 95%CI: 1.57–2.24). The highest risk was found in women with a proliferative benign breast disease with atypia (aHR, 4.35; 95%CI: 2.09–9.08, and 3.35; 95%CI: 1.51–7.40 for those diagnosed at incident and prevalent screens, respectively), while the lowest was found in women with non-proliferative benign breast disease (aHR, 2.39; 95%CI: 1.95–2.93, and 1.63; 95%CI: 1.32–2.02 for those diagnosed at incident and prevalent screens, respectively).ConclusionOur study showed that the risk of breast cancer conferred by a benign breast disease differed according to type of screen (prevalent or incident). To our knowledge, this is the first study to analyse the impact of the screening type on benign breast disease prognosis.     

Unresected screen-detected ductal carcinoma in situ: Outcomes of 311 women in the Forget-Me-Not 2 study

Background and aimThe natural history of ductal carcinoma in situ (DCIS) is poorly understood. The aim of this cohort study was to determine the outcomes of women who had no surgery for screen-detected DCIS in the 6 months following diagnosis.MethodsEnglish breast screening databases were retrospectively searched for women diagnosed with DCIS without invasive cancer at screening and who had no record of surgery within 6 months of diagnosis. These were cross-referenced with cancer registry data. Details of the potentially eligible women were sent to the relevant breast screening units for verification and for completion of data forms detailing clinical, radiological and pathological findings, non-surgical treatment and subsequent clinical course.ResultsData for 311 eligible women (median age 62 years) were available. 60 women developed invasive cancer, 56 ipsilateral and 4 contralateral. Ipsilateral invasion risk increased approximately linearly with time for at least 10 years. The 10-year cumulative risk of ipsilateral invasion was 9% (95% CI 4–21%), 39% (24–58%) and 36% (24–50%) for low, intermediate and high grade DCIS respectively and was higher in younger women, in those with larger DCIS lesions and in those with microinvasion. Most invasive cancers that developed were grade 2 or 3.ConclusionThe findings suggest that active surveillance may be a reasonable alternative to surgery in patients with low grade DCIS but that women with intermediate or high grade disease should continue to be offered surgery. This highlights the importance of reproducible grading of DCIS to ensure patients receive appropriate treatment.     

Does screen-detected breast cancer have better survival than symptomatic breast cancer?

OBJECTIVES: Evidence obtained from several randomized control trials suggest that mortality from breast cancer could be reduced by mammographic screening. However, a recent meta-analysis questioned the general acceptance that screening for breast cancer is beneficial. The purpose of the study was to analyze prospectively collected data from our unit and produce overall and comparative 5-year survival rates for screen-detected and symptomatic breast cancer. METHODS: Prospectively collected data on all patients diagnosed with invasive breast cancer between January 1993 and December 1994 (24 months), and monitored until the end of 1999, were collated and analyzed. Five-year survival was estimated and broken down by age at diagnosis, tumour size, grade and nodal status. The overall 5-year survival for women with screen-detected cancers was compared with that for women with symptomatically presenting cancers. RESULTS: Between January 1993 and December 1994, 308 patients with invasive breast cancer were referred to the unit (162 via the breast screening programme and 146 presenting symptomatically). The overall 5-year survival was 85.5% (confidence interval [CI], 80.8-89.1). Small tumour size, low grade and negative nodal status were associated with higher survival rates. Five-year survival of the screen-detected cancer patients (91.7%; CI, 85.8-95.2) was higher than that of patients presenting symptomatically (78.6%; CI, 70.6-84.6; p < 0.001). CONCLUSIONS: These findings suggest that patients with screen-detected breast cancer may have better survival compared to those with symptomatically detected breast cancer. The results support the argument in favour of a beneficial impact of breast screening programmes on patients' survival.     

Overdiagnosis in breast imaging

The main harm of overdiagnosis is overtreatment. However a form of overdiagnosis also occurs when foci of cancer are found by imaging in addition to the symptomatic lesion when this leads to additional treatment which does not benefit the patient. Even if overtreatment is avoided, knowledge of the diagnosis can still cause psychological harm.Overdiagnosis is an inevitable effect of mammographic screening as the benefit comes from diagnosing breast cancer prior to clinical detectability. Estimates of the rate of overdiagnosis at screening are around 10%. DCIS represents 20% of cancers detected by screening and is the main focus in the overdiagnosis debate. Detection and treatment of low grade DCIS and invasive tubular cancer would appear to represent overdiagnosis in most cases. Supplementary screening with tomosynthesis or US are both likely to increase overdiagnosis as both modalities detect predominantly low grade invasive cancers. MRI causes overdiagnosis because it is so sensitive that it detects real tumour foci which after radiotherapy and systemic therapy do not, in many cases go on and cause local recurrence if the women had had no MRI and undergone breast conservation and adjuvant therapy with these small foci left in situ.     

Interval breast cancers in the ‘screening with tomosynthesis or standard mammography’ (STORM) population-based trial

Background & methodsThe prospective ‘screening with tomosynthesis or standard mammography’ (STORM) trial recruited women participating in biennial breast screening in Italy (2011–2012), and compared sequential screen-readings based on 2D-mammography alone or based on tomosynthesis (integrated 2D/3D-mammography). The STORM trial showed that tomosynthesis screen-reading significantly increased breast cancer detection compared to 2D-mammography alone. The present study completes reporting of the trial by examining interval breast cancers ascertained at two year follow-up.Results9 interval breast cancers were identified; the estimated interval cancer rate was 1.23/1000 screens [9/7292] (95%CI 0.56 to 2.34) or 1.24/1000 negative screens [9/7235] (95%CI 0.57 to 2.36). In concurrently screened women who attended the same screening services and received 2D-mammography, interval cancer rate was 1.60/1000 screens [40/25,058] (95% CI 1.14 to 2.17) or 1.61/1000 negative screens [40/24,922] (95% CI 1.15 to 2.18). Estimated screening sensitivity for the STORM trial was 85.5% [59/69] (95%CI 75.0%–92.8%), and that for 2D-mammography screening was 77.3% [136/176] (95%CI 70.4%–83.2%).ConclusionInterval breast cancer rate amongst screening participants in the STORM trial was marginally lower (and screening sensitivity higher) than estimates amongst 2D-screened women; these findings should be interpreted with caution given the small number of interval cases and the sample size of the trial. Much larger screening studies, or pooled analyses, are required to examine interval cancer rates arising after breast tomosynthesis screening versus digital mammography screening.     

Survival of south african women with breast cancer receiving anti-retroviral therapy for HIV

PurposeBreast cancer outcomes in sub-Saharan Africa is reported to be poor, with an estimated five-year survival of 50% when compared to almost 90% in high-income countries. Although several studies have looked at the effect of HIV in breast cancer survival, the effect of ARTs has not been well elucidated.MethodsAll females newly diagnosed with invasive breast cancer from May 2015–September 2017 at Charlotte Maxeke Johannesburg Academic and Chris Hani Baragwanath Academic Hospital were enrolled. We analysed overall survival and disease-free survival, comparing HIV positive and negative patients. Kaplan-Meier survival curves were generated with p-values calculated using a log-rank test of equality while hazard ratios and their 95% confidence intervals (CIs) were estimated using Cox regression models.ResultsOf 1019 patients enrolled, 22% were HIV positive. The overall survival (95% CI) was 53.5% (50.1–56.7%) with a disease-free survival of 55.8% (52.1–59.3) after 4 years of follow up. HIV infection was associated with worse overall survival (HR (95% CI): 1.50 (1.22–1.85), p < 0.001) and disease-free survival (OR (95% CI):2.63 (1.71–4.03), p < 0.001), especially among those not on ART at the time of breast cancer diagnosis. Advanced stage of the disease and hormone-receptor negative breast cancer subtypes were also associated with poor survival.ConclusionHIV infection was associated with worse overall and disease-free survival. HIV patients on ARTs had favourable overall and disease-free survival and with ARTs now being made accessible to all the outcome of women with HIV and breast cancer is expected to improve.     

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

BackgroundDetected 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.MethodsWe 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.ResultsA 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).DiscussionBilateral 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.     

Patterns and determinants of surgical management of screen detected breast cancer in the South-East Netherlands

IntroductionPatients with screen detected breast cancer tend to have small, non-palpable tumours with favourable characteristics for breast conserving surgery (BCS). The aims of this study were to analyse patterns in surgical management in patients with screen detected breast cancer and to determine factors predictive of the need for a re-operation after BCS (re-excision or secondary mastectomy).MethodsPatient data were retrieved from the population based Eindhoven Cancer Registry, which covers 14 hospitals in de south of the Netherlands. Data of patients aged 50–74 years, diagnosed with operable, invasive, non-metastasised, T1 or T2 tumours in the period from 1999 to 2005 were linked to the patients recorded by the Dutch Breast Screening Organisation to identify the screen-detected cancers.ResultsA total of 5657 patients were diagnosed with early stage invasive breast cancer. In 2822 of the 5657 patients (50%) breast cancer was detected by screening. Eighty percent of the screen-detected breast cancers was smaller than 2 cm. Of all 2822 patients with screen-detected cancer 82% underwent primary BCS. From 1999 until 2006 the percentage of re-excisions after this primary BCS decreased from 14% to 8% and the percentage of secondary mastectomies decreased from 23% to 8%. Primary BCS rates ranged from 64% to 93% between the 14 hospitals. Multivariable analyses showed that tumour size >2 cm, lobular histology, axillary nodal tumour involvement and poor differentiation of the tumour were associated with a statistically significant increase in the risk of re-operation after BCS.ConclusionThe need for a second operation after breast conserving surgery in patients with screen-detected breast cancer has decreased significantly in the southern Netherlands since 1999. However, considerable variation in surgical approach and re-operation rate between hospitals was observed.     

Treatment Intensity Differences After Early-Stage Breast Cancer (ESBC) Diagnosis Depending on Participation in a Screening Program

Background

While population mammographic screening identifies early-stage breast cancers (ESBCs; ductal carcinoma in situ [DCIS] and invasive disease stages 1–3A), commentaries suggest that harms from overdiagnosis and overtreatment may outweigh the benefits. Apparent benefits to patients with screen-detected cancers may be due to selection bias from exclusion of interval cancers (ICs). Treatment intensity is rarely discussed, with an assumption that all ESBCs are treated similarly. We hypothesized that women diagnosed while in a screening program would receive less-intense treatment than those never or not recently screened (NRS).

Methods

This was a retrospective analysis of all women aged 50–69 years managed for ESBC (invasive or DCIS) during the period 2007–2013 within a single service, comparing treatment according to screening status. Data on demographics, detection, pathology, and treatment were derived from hospital, cancer registry, and screening service records.

Results

Overall, 622 patients were active screeners (AS) at diagnosis (569 screen-detected and 53 ICs) and 169 patients were NRS. AS cancers were smaller (17 mm vs. 26 mm, p?<?0.0001), less likely to involve nodes (26% vs. 48%, p?<?0.0001), and lower grade. For invasive cancer, NRS patients were more likely to be recommended for mastectomies [35% vs. 16%; risk ratio(RR) 2.2, p?<?0.0001], axillary dissection (43% vs. 19%; RR 2.3, p?<?0.0001), adjuvant chemotherapy (65% vs. 37%; RR 1.7, p?<?0.0001), and postmastectomy radiotherapy (58% vs. 39%; RR 1.5, p?=?0.04).

Conclusion

Participants in population screening diagnosed with ESBC receive substantially less-intense treatment than non-participants. Differences persist when potential overdiagnosis is taken into account; these differences should be factored into debates around mammographic screening.

     

Screen‐detected breast cancer compared to symptomatic presentation: An analysis of surgical treatment and end‐points of effective mammographic screening

Background : Mammographic screening has been shown to reduce mortality from breast cancer and to offer more opportunity for breast conservation surgery (BCS). The minimum standards (or surrogate end‐points) that need to be achieved by a screening programme if it is to reduce mortality have been derived from the Two County Study. Three surrogate end‐points that can be used to gauge the quality of the screening service are that 50% of the identified infiltrating cancers should be < 15 mm; at least 30% of grade 3 cancers should be < 15 mm; and 70% of screen‐detected cancers should have a negative axillary dissection. The present study assesses these end‐points of effective screening in an urban population referred to The Strathfield Breast Centre (TSBC). The screening end‐points and surgical treatment of one group of women referred with a BreastScreen New South Wales (NSW)‐detected breast cancer (screen group) were compared to all the other, mostly symptomatic, breast cancer referrals (symptom group). The problems with the current pattern of acceptance of mammographic screening in TSBC’s referral area are discussed. Methods : A prospective non‐randomized study was done via analysis of the prospective database at The Strathfield Breast Centre (TSBC). Results : There were 224 women in the screen group and 657 women in the symptom group. The mean tumour size was 18.1 mm in the screen group and 22.1 mm in the symptom group. There were significantly more small invasive cancers (< 15 mm) in the screen group (58%) compared with the symptom group (33%; P < 0.001). In the screen group there were more low‐grade tumours but 30% of grade 3 tumours were < 15 mm compared with 16% in the symptom group (P = 0.009). In patients with invasive cancers who underwent axillary dissection, there was a significant difference in axillary node negativity, being 72% in the screen group and 59% in the symptom group (P = 0.003). In the screen group 64% of women had BCS compared with 51% in the symptom group (P = 0.002). Conclusions : These end‐points of effective mammographic screening were met in the BreastScreen NSW group of women who were referred to TSBC despite the biases involved which could lessen the effectiveness of the screening programme. This crudely translated into a significant reduction in breast cancer mortality but selection and lead time bias has to be taken into account in evaluation of these data. There was a significantly greater chance of BCS in the screen group.     

Statin use and patterns of breast cancer recurrence in the Malmö Diet and Cancer Study

BackgroundAccumulating evidence suggests that statins have a beneficial effect on breast cancer prognosis. Previous studies have reported a positive association between statin use and breast cancer survival; however, the relationship between statin use and patterns of breast cancer recurrence remains unclear.Patients and methodsWe identified all Malmö Diet and Cancer Study (MDCS) participants diagnosed with incident invasive breast cancer between 2005 and 2014. The follow-up period began at breast cancer diagnosis and continued until the first invasive breast cancer recurrence event, death, emigration or the end of the follow-up (June 8, 2020). We estimated incidence rates (IRs) of recurrence and fit Cox regression models to compute crude and adjusted hazard ratios (HRs) with 95% confidence intervals (95% CIs) for disease recurrence to compare post-diagnosis statin users with non-users.ResultsThe final study cohort consisted of 360 eligible patients with a median follow-up of 8.6 years. Overall, there were 71 recurrences in 2932 total person-years. According to statin use, there were 14 recurrences in 595 person-years among statin users, and 57 recurrences in 2337 person-years in non-users. Statin use was associated with a reduced risk of breast cancer recurrence (HR_adj = 0.88 [95% CI: 0.82–0.96]). Regarding the pattern of recurrence, statin use was associated with a reduced risk of distant recurrence (HR_adj = 0.86 [95% CI: 0.80–0.94]) but not loco-regional recurrence (HR_adj = 0.97 [95% CI: 0.87–1.08]).ConclusionIn the MDCS, statin use was associated with a reduced risk of distant breast cancer recurrence, whereas no association between statin use and loco-regional breast cancer recurrence was found. This site-based difference in disease recurrence may be explained by statin's inhibition of epithelial-mesenchymal transition.     

Patterns of care for ductal carcinoma in situ of the breast: Queensland's experience over a decade

ObjectivesTo review management of ductal carcinoma in situ (DCIS) of the breast in Queensland, with reference to breast conserving surgery (BCS) and adjuvant radiation therapy (RT). In addition, we examined the incidence of invasive breast cancer recurrence and factors predictive of invasive recurrence.Materials and methodsA retrospective review of the Queensland Oncology Repository identified women with resected DCIS (TisN0) ± adjuvant RT between 2003 and 2012. Time to invasive breast cancer recurrence was analysed using the Kaplan Meier method. Median follow-up was 4.9 years.Results3038 women had surgery. 940 (31%) had mastectomy and 2098 (69%) underwent BCS. Of 2098 women having BCS, 1100 (52%) received BCS alone and 998(48%) received adjuvant RT. The use of RT significantly increased over the decade from 25% to 62% (p=<0.001). Clinicopathological factors associated with RT use on multivariate analysis included age ≤70, higher socioeconomic status, larger tumour size, higher nuclear grade and surgical margins ≤5 mm. Invasive breast cancer recurrence at 5 years was 1.7% [95% CI 1.0–3.0] in RT group versus 2.8% [95% CI 2.1–3.8] in BCS alone group. Factors associated with increased risk of invasive recurrence on multivariate analysis were age <40 and surgical margins ≤2 mm.ConclusionThe use of adjuvant RT in Queensland significantly increased between 2003 and 2012. Selection of patients for RT was based on clinicopathological factors associated with higher recurrence risk. Although longer follow-up is required, the selective use of radiation therapy after BCS is associated with a low rate of invasive breast cancer recurrence at 5 years.     

A Population‐Based Cross‐Sectional Study Comparing Breast Cancer Stage at Diagnosis between Immigrant and Canadian‐Born Women in Ontario

There is limited information on stage at breast cancer diagnosis in Canadian immigrant women. We compared stage at diagnosis between immigrant women and Canadian‐born women, and determined whether ethnicity was an independent factor associated with stage. 41,213 women with invasive breast cancer from 2007 to 2012 were identified from the Ontario Cancer Registry. Women were classified as either immigrants or Canadian‐born by linkage with the Immigration, Refugees, and Citizenship Canada's Permanent Resident database. Women's ethnicity was classified as Chinese, South Asian, or remaining women in Ontario. Logistic regression was performed to calculate the odds ratio (OR) of being diagnosed at stage I breast cancer (versus stage II–IV). 4,353 (10.6%) women were immigrants and 36,860 (89.4%) were Canadian‐born women. The mean age at breast cancer diagnosis was 53.5 years for immigrants versus 62.3 years for Canadian‐born women (p < 0.0001). Immigrant women were less likely than Canadian‐born women to be diagnosed with stage I breast cancers (adjusted OR = 0.85; 95% CI: 0.79–0.91; p < 0.0001). The adjusted OR of being stage I was 1.28 (95% CI: 1.14–1.43; p < 0.0001) for women of Chinese ethnicity and was 0.82 (95% CI: 0.70–0.96; p = 0.01) for women of South Asian ethnicity, compared to the remaining women in Ontario. Canadian immigrant women were less likely than Canadian‐born women to be diagnosed with early‐stage breast cancers. Ethnicity was a greater contributor to the stage disparity than was immigrant status. South Asian women, regardless of immigration status, might benefit from increased breast cancer awareness programs.     

Early Detection of Breast Cancer through Population-Based Mammographic Screening in Asian Women: A Comparison Study between Screen-Detected and Symptomatic Breast Cancers

Abstract: The first nation‐wide mammographic screening program in Asia, BreastScreen Singapore (BSS), was launched in Singapore in January 2002. This study compared the presentation and results of screen‐detected breast cancers with symptomatic breast cancers in two affiliated high‐volume institutions, one of which was an assessment centre for BSS. The medical records of patients diagnosed with primary breast cancer at the Department of General Surgery, Singapore General Hospital and the Department of Surgical Oncology, National Cancer Centre, Singapore, during the period January 2002 to December 2003 were reviewed. Clinical and pathological comparisons were made between screen‐detected lesions and symptomatic lesions. Of a total of 767 cases, 640 (83.4%) were invasive carcinomas and 127 (16.6%) were ductal carcinoma in‐situ (DCIS) lesions. Only 13.4% of them were screen‐detected. Compared to symptomatic cancers, screen‐detected lesions were of smaller size (median size 18 versus 23 mm), a lower stage (stages 0–2, 95 versus 83.2%) and histologic grade (grade 1–2, 71 versus 60%), with a higher incidence of DCIS (31.0 versus 14.3%) and had higher rates of breast conservation (45.6 versus 28.2%) (all p‐values <0.05). By multivariate analysis, tumor palpability, tumor size >20 mm, nodal involvement, cerbB2 overexpression, and advanced disease stage were independent poor prognostic factors for disease‐free survival, whereas nodal involvement, advanced disease, and recurrence predicted poor cancer‐specific survival. However, there was no statistically significant difference in disease‐free survival or cancer‐specific survival between the two groups at a median follow‐up of 38 months. Screening mammography has allowed the detection of smaller and hence oncologically more favorable lesions in Asian women. Although no significant survival benefit was demonstrated in our study, a longer period of follow‐up is essential before the benefit of mortality reduction, as a result of mammography screening becomes evident in our population.