Breast cancer in Singapore: some perspectives

Temporal trends of breast cancer burden in the Western Pacific Region from 1990 to 2044: Implications from the Global Burden of Disease Study 2019

INTRODUCTION

Breast cancer (BC) is a malignant disease that occurs worldwide and poses serious health burden.

OBJECTIVES

To assess the prevalence of BC burden in the Western Pacific region (WPR) from 1990 to 2019, and to predict trends from 2020 to 2044. To analyze the driving factors and put forward the region-oriented improvement.

METHODS

Based on the Global Burden of Disease Study 2019, BC cases, deaths, disability-adjusted life years (DALYs) cases, age-standardized incidence rate (ASIR), age-standardized death rate (ASDR), and age-standardized DALYs rate in WPR from 1990 to 2019 was obtained and analysed. Age-period-cohort (APC) model was used to analyze age, period, and cohort effects in BC, and Bayesian APC (BAPC) was used to predict trends over the next 25 years.

RESULTS

In conclusion, BC incidence and deaths in the WPR have increased rapidly over the past 30 years and are expected to continue to increase between 2020 and 2044. Among behavioral and metabolic factors, high body-mass index was the main risk factor for BC mortality in middle-income countries, whereas alcohol use was the main risk factor in Japan. Age is a key factor in the development of BC, with 40 years being the critical point. Incidence trends coincide with the course of economic development.

CONCLUSIONS

The BC burden remains an essential public health issue in the WPR and will increase substantially in the future. More efforts should be made in middle-income countries to prompt the health behavior and minimize the burden of BC because these nations accounts for the majority of BC burden in the WPR.

Cost-effectiveness analysis of add-on pertuzumab to trastuzumab biosimilar and chemotherapy as neoadjuvant treatment for human epidermal growth receptor 2-positive early breast cancer patients in Singapore

OBJECTIVES

The Asian PEONY trial showed that add-on pertuzumab to trastuzumab and chemotherapy significantly improved pathological complete response in the neoadjuvant treatment of patients with human epidermal growth factor receptor 2-positive (HER2+) early breast cancer (EBC). This study evaluated the cost-effectiveness of pertuzumab as an add-on therapy to trastuzumab and chemotherapy for neoadjuvant treatment of patients with HER2+ EBC in Singapore.

METHODS

A six-state Markov model was developed from the Singapore healthcare system perspective, with a lifetime time horizon. Model outputs were: costs; life-years (LYs); quality-adjusted LYs (QALYs); incremental cost-effectiveness ratios (ICERs). Sensitivity/scenario analyses explored model uncertainties.

RESULTS

The base case projected the addition of pertuzumab to be associated with improved outcomes by 0.277 LYs and 0.271 QALYs, increased costs by S$1,387, and an ICER of S$5,121/QALY. The ICER was most sensitive to the pCR rate, and the probabilistic sensitivity analysis showed that add-on pertuzumab had an 81.3% probability of being cost-effective at a willingness-to-pay threshold of S$45,000/QALY gained.

CONCLUSIONS

This model demonstrated that the long-term clinical impact of early pertuzumab use, particularly the avoidance of metastatic disease and thus avoidance of higher costs and mortality rates, make neoadjuvant pertuzumab a cost-effective option in the management of patients with HER2+ breast cancer in Singapore.

Illuminating the breast cancer survival rates among Southeast Asian women: A systematic review and meta-analysis spanning four decades

In Southeast Asia, breast cancer is the most prevalent cancer among women and ranks as the second leading cause of cancer-related deaths. This systematic review and meta-analysis, encompassing 27 observational cohort studies with a minimum one-year follow-up period, aimed to examine temporal trends in breast cancer survival rates. Among the subset of five out of eleven Southeast Asian nations with available data, our analysis revealed pooled survival rates of 88.8 % at 1 year, 73.8 % at 3 years, 70.8 % at 5 years, and 49.3 % at 10 years for breast cancer patients. The mean age at diagnosis was 50.77±10.07 years, with 52.81 % of patients presenting with positive lymph nodes. Notably, stages I and II remained predominant even five years post-diagnosis. Although an overall amelioration in survival rates transpired over the preceding four decades, a noticeable exception pertained to the 3-year rate, demonstrating limited improvement. These findings underscore the pressing need for enhanced research efforts, particularly in countries within the region that lack survival data, to enable accurate estimations. Furthermore, our review also emphasizes the crucial need for future comprehensive, well-designed studies to delve into the factors behind survival rate disparities in Southeast Asia and the younger age at diagnosis compared to other regions.

Tertiary lymphoid structures in breast ductal carcinoma in situ correlate with adverse pathological parameters

AIMS

To investigate tertiary lymphoid structures (TLSs) in ductal carcinoma in situ (DCIS) of the breast and their correlation with pathological features, immune cell markers and clinical outcomes.

METHODS AND RESULTS

Morphological identification of TLSs in 198 DCIS cases incorporated B and T cell zones with high endothelial venules. TLS positivity was defined as ≥ 1 TLSs in lesional areas, while TLS area percentage was divided into two categories: low (TLSs < 5%) and high (TLSs ≥ 5%). Previously reported biomarkers included ER, PR, HER2, CD68, CD163, CD4, CD8 and PD-L1. TLSs were observed in 24.7% (49 of 198) of cases, with a mean diameter of 0.44 mm (median = 0.4 mm, range = 0.12-1.43 mm). TLSs were significantly associated with higher nuclear grade, presence of necrosis, hormone receptor negativity/HER2 positivity, triple negativity, tumour infiltrating lymphocytes (TILs) and immune related biomarkers such as FOXP3, CD163, CD4 and CD4/CD8 ratio (all P < 0.05). There were no significant associations between TLSs and recurrence, but a combination of TLSs^high with FOXP3⁺ , CD4^high , CD4/CD8 ratio^high and CD68^high individually, compared with all other combinations, disclosed significantly poorer disease-free survival (DFS) for ipsilateral invasive recurrence (IIR) on both Kaplan-Meier and multivariable Cox regression analyses (all P < 0.05).

CONCLUSIONS

TLSs in DCIS were associated with unfavourable prognostic features, TILs and immune cell markers in our study. TLSs^high /FoxP3⁺ , TLSs^high /CD4^high , TLSs^high /(CD4/CD8) ratio^high and TLSs^high /CD68^high were independent factors for poorer DFS for IIR. Further exploration of the pathological significance of TLSs may provide a clinical basis for their recognition as an important structure and functional unit in the tumour immune microenvironment.

Clinical presentations and outcomes of young women aged <40 yrs with Ductal carcinoma in situ

INTRODUCTION

Ductal carcinoma in situ (DCIS) in young women is rare and not well studied. Since they do not qualify for mammographic screening, they are more likely to present with symptoms. Young women have also been associated with poorer outcomes, but it is unknown whether presentation mode affects outcome. We aimed to compare characteristics of DCIS patients <40 years of age presenting with symptoms versus those without, and determine whether presentation mode affects recurrence.

METHODS

Pure DCIS patients aged <40 years were retrospectively analyzed. Clinical presentation, pathology and recurrence data were collected. Statistical analysis was performed to investigate the correlation of presentation mode with outcomes.

RESULTS

40 patients with 41 cases were included. The mean age at diagnosis was 32.3 years (range 17-39). 73.2% and 26.8% presented with symptoms or abnormal imaging respectively. Of the cases who presented with symptoms, 86.7%, 10.0% and 3.3% had palpable lump, nipple discharge or breast pain, respectively. The average tumor size was 22.0 mm (range 2.0-86.9) and 12.2 mm (range 3-25) for patients who presented with symptoms and non-symptomatic group, respectively. Cases presenting with symptoms were statistically associated with higher grade (p = 0.0090). On median follow-up of 85 months, there were 3 (7.3%) recurrences, which were not statistically associated with presentation mode.

CONCLUSION

Young women with DCIS tend to present with symptoms, with breast lump as the commonest symptom. Symptomatic patients tend to be associated with grade III tumours, compared to non-symptomatic patients. On long-term follow-up, mode of presentation was not statistically associated with recurrence.

Polygenic risk scores for prediction of breast cancer risk in Asian populations

PURPOSE

Non-European populations are under-represented in genetics studies, hindering clinical implementation of breast cancer polygenic risk scores (PRSs). We aimed to develop PRSs using the largest available studies of Asian ancestry and to assess the transferability of PRS across ethnic subgroups.

METHODS

The development data set comprised 138,309 women from 17 case-control studies. PRSs were generated using a clumping and thresholding method, lasso penalized regression, an Empirical Bayes approach, a Bayesian polygenic prediction approach, or linear combinations of multiple PRSs. These PRSs were evaluated in 89,898 women from 3 prospective studies (1592 incident cases).

RESULTS

The best performing PRS (genome-wide set of single-nucleotide variations [formerly single-nucleotide polymorphism]) had a hazard ratio per unit SD of 1.62 (95% CI = 1.46-1.80) and an area under the receiver operating curve of 0.635 (95% CI = 0.622-0.649). Combined Asian and European PRSs (333 single-nucleotide variations) had a hazard ratio per SD of 1.53 (95% CI = 1.37-1.71) and an area under the receiver operating curve of 0.621 (95% CI = 0.608-0.635). The distribution of the latter PRS was different across ethnic subgroups, confirming the importance of population-specific calibration for valid estimation of breast cancer risk.

CONCLUSION

PRSs developed in this study, from association data from multiple ancestries, can enhance risk stratification for women of Asian ancestry.

Cost effectiveness analysis of a polygenic risk tailored breast cancer screening programme in Singapore

BACKGROUND

This study aimed to evaluate the cost-effectiveness of a breast cancer screening programme that incorporates genetic testing using breast cancer associated single nucleotide polymorphisms (SNPs), against the current biennial mammogram-only screening programme to aid in its implementation into the current programme in Singapore.

METHODS

A Markov model was used to compare the costs and health outcomes of the current screening programme, against a polygenic risk-tailored screening programme, which can advise a long-term screening strategy depending on the individual's polygenic risk. The model took the perspective of the healthcare system, with a time horizon of 40 years, following women from the age of 35 to 74. Epidemiological and cost data were taken from Asian studies, and an annual discount rate of 3% was used. The model outcome was the incremental cost-effectiveness ratio (ICER), calculated from the difference in costs per quality-adjusted life year (QALY). Scenarios with varying risk thresholds for each polygenic risk group were examined. One-way and probabilistic sensitivity analyses were performed to assess parameter uncertainty.

RESULTS

The ICER for a polygenic risk-tailored breast cancer screening programme, compared with the current biennial mammogram-only screening programme, was - 3713.80 SGD/QALY, with incremental costs < 0 and incremental effects > 0. The scenario analysis of different polygenic risk cutoffs showed that the ICERs remain negative, with all ICERs falling within the south-east quadrant of the cost-effectiveness plane, indicating that tailored screening is more cost effective than mammogram-only screening, with lower costs and higher QALYs to be gained. This suggests that a polygenic risk-tailored breast cancer screening programme is cost effective, entailing lower cost than the current mammogram-only programme, while causing no additional harm to women.

CONCLUSION

Results from this cost-effectiveness analysis show that polygenic risk-tailored screening is cost effective with an ICER of - 3713.80 SGD/QALY. Tailored screening remains cost effective even across varying percentile cutoffs for each risk group. While the results look promising for incorporating polygenic risk into the current breast cancer screening programme, further studies should be conducted to address various limitations.

Higher densities of tumour-infiltrating lymphocytes and CD4+ T cells predict recurrence and progression of ductal carcinoma in situ of the breast

AIMS

Host immunity influences cancer progression and therapeutic response. We investigated the potential of tumour-infiltrating lymphocytes (TILs) around ductal carcinoma in situ (DCIS) in predicting recurrence and progression.

METHODS AND RESULTS

CD4, CD8, programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) expression in DCIS from 198 patients was determined by immunohistochemistry. We correlated disease-free survival (DFS), clinicopathological parameters and biomarker expression with TIL density and CD4/CD8 ratio. High TIL density was associated with high nuclear grade (P < 0.001), DCIS PD-L1 expression (P = 0.008), TIL PD-L1 expression (P < 0.001), oestrogen (ER) negativity (P < 0.001), progesterone (PR) negativity (P < 0.001), human epidermal growth factor receptor 2 (HER2) positivity (P = 0.002) and triple negativity (P = 0.001). TIL PD-L1 expression was associated with triple-negative DCIS (P = 0.028). TIL density was associated with molecular subtypes (P < 0.001). High CD4⁺ T cell density was associated with high nuclear grade (P = 0.001), microinvasion (P = 0.037), ER negativity (P < 0.001), PR negativity (P = 0.001), HER2 positivity (P = 0.004), triple negativity (P = 0.023) and PD-L1 expression in TILs (P < 0.011). High CD4/CD8 ratio was associated with PD-L1 expression in DCIS (P = 0.035) and TILs (P < 0.001). DCIS with higher TIL density disclosed worse DFS (P = 0.012) and was affirmed with multivariate analysis [95% confidence interval (CI) = 1.109-2.554, hazard ratio (HR) = 1.683, P = 0.014]. Poorer DFS for ipsilateral invasive recurrence was found for DCIS with higher CD4⁺ T cell density (P = 0.006) or CD4/CD8 ratio (P = 0.02), confirmed by multivariate analysis for the former (95% CI = 1.369-10.196, HR = 3.736, P = 0.01) and latter (95% CI = 1.311-7.935, HR = 3.225, P = 0.011).

CONCLUSION

DCIS with higher TIL density was associated with poorer prognostic parameters and predicted recurrence, while both CD4⁺ T cell density and CD4/CD8 ratio were associated with both recurrence and ipsilateral invasive recurrence.

Incidence of breast cancer attributable to breast density, modifiable and non-modifiable breast cancer risk factors in Singapore

Incidence of breast cancer is rising rapidly in Asia. Some breast cancer risk factors are modifiable. We examined the impact of known breast cancer risk factors, including body mass index (BMI), reproductive and hormonal risk factors, and breast density on the incidence of breast cancer, in Singapore. The study population was a population-based prospective trial of screening mammography - Singapore Breast Cancer Screening Project. Population attributable risk and absolute risks of breast cancer due to various risk factors were calculated. Among 28,130 women, 474 women (1.7%) developed breast cancer. The population attributable risk was highest for ethnicity (49.4%) and lowest for family history of breast cancer (3.8%). The proportion of breast cancers that is attributable to modifiable risk factor BMI was 16.2%. The proportion of breast cancers that is attributable to reproductive risk factors were low; 9.2% for age at menarche and 4.2% for number of live births. Up to 45.9% of all breast cancers could be avoided if all women had breast density <12% and BMI <25 kg/m². Notably, sixty percent of women with the lowest risk based on non-modifiable risk factors will never reach the risk level recommended for mammography screening. A combination of easily assessable breast cancer risk factors can help to identify women at high risk of developing breast cancer for targeted screening. A large number of high-risk women could benefit from risk-reduction and risk stratification strategies.

Higher density of stromal M2 macrophages in breast ductal carcinoma in situ predicts recurrence

Immune response can affect tumour progression and treatment outcome. This study investigated the potential of stromal macrophages around ductal carcinoma in situ (DCIS) in predicting recurrence and progression. CD68 and CD163 expression of macrophages in DCIS from 198 patients was determined by immunohistochemistry. Disease free survival (DFS), clinicopathological parameters and biomarker expression were correlated with the densities of both CD68⁺ and CD163⁺ macrophages. High CD68⁺ macrophage density was associated with high nuclear grade (p < 0.001), oestrogen receptor (ER) negativity (p = 0.029), progesterone receptor (PR) negativity (p = 0.008) and human epidermal growth factor receptor 2 (HER2) positivity (p < 0.001). High CD163⁺ macrophage density was associated with high nuclear grade (p = 0.003), microinvasion (p = 0.01), ER negativity (p < 0.001), PR negativity (p = 0.001), HER2 positivity (p = 0.001) and triple negativity (p = 0.022). DCIS with higher CD68⁺ macrophage density disclosed significantly worse DFS for ipsilateral invasive recurrence (p = 0.004) and is affirmed by multivariate Cox regression analysis (95% CI 1.126-5.102, HR = 2.397, p = 0.023). DCIS with higher CD163⁺ macrophage density showed significantly worse DFS for both recurrence (p = 0.001) and ipsilateral invasive recurrence (p = 0.001). These findings, for CD163⁺ macrophage density, were affirmed by multivariate Cox regression analysis respectively for both recurrence (95% CI 1.210-2.293, HR = 1.880, p = 0.005) and ipsilateral invasive recurrence (95% CI 1.122-5.176, HR = 2.410, p = 0.024). This study demonstrated that DCIS with higher macrophage density was associated with poorer prognostic parameters, while DCIS with higher CD163⁺ macrophage density predicted both  recurrence and ipsilateral invasive recurrence.

Occupational exposure to endocrine disrupting substances and the risk of breast Cancer: the Singapore Chinese health study

Background

Evidence from basic research links exposure to endocrine disrupting chemicals (EDCs) with a higher risk for breast cancer. However, there is less evidence from observational epidemiological research and the results are equivocal. Therefore, we examined the association between occupational exposure to substances where exposure to EDCs is likely and the risk of breast cancer.

Methods

A prospective study consisting of a population-based cohort of 33,458 Singaporean Chinese women aged 45–74 years enrolled in the Singapore Chinese Health Study (SCHS) from 1993 to 98 and followed through 2014. Subjects’ self-reported occupational exposure and duration to industries, job titles, and substance types were garnered at baseline, and cases of incident breast cancer (N = 988) were determined by linkage with the Singapore Cancer Registry. Hazard ratios (HR) and 95% confidence intervals (CI) were estimated for exposure to substances, job titles, and industries.

Results

There was no association between cumulative exposure to substances via occupation where EDC exposure is likely and risk of breast cancer. These results were consistent for hypothesized high (HR 0.94, 95% CI: 0.66–1.35), medium (HR 1.03 95% CI: 0.77–1.38) and low (HR 0.74, 95% CI 0.48–1.13) combined substance exposure groups when compared with those who were not exposed via occupation. Similar null associations were observed when examining job titles and industry categories.

Conclusions

There was no association between EDC related occupational exposures and breast cancer risk in working women of the Singaporean Chinese Health Study. Future studies that employ rigorous methods with regard to exposure assessment of EDCs are needed.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5862-2) contains supplementary material, which is available to authorized users.

Evaluation of the relative effectiveness of the 2017 updated Manchester scoring system for predicting BRCA1/2 mutations in a Southeast Asian country

BACKGROUND

Germline mutations in the BRCA1 and BRCA2 genes have significant clinical implications for both risk-reducing and early surveillance management. The third and most recent revision of the Manchester scoring system (MSS3) used to distinguish patients indicated for germline BRCA1/2 testing included further adjustments for triple negative breast cancer, high-grade serous ovarian cancer and human epidermal growth factor 2 (HER2) receptor status. This study aims to evaluate the relative effectiveness of MSS3 in a Southeast Asian population.

METHODS

All patients in our centre were tested using next-generation sequencing (NGS) panels that included full gene sequencing as well as coverage for large deletions/duplications in BRCA1/2. We calculated MSS1-3 scores for index patients between 2014 and 2017 who had undergone BRCA1/2 genetic testing and recorded their genetic test results. MSS1-3 outcomes were compared using receiver operating characteristic analysis, while associations with predictors were investigated using Fisher's exact test and logistics regression. Calculations were performed using Medcalc17.

RESULTS

Of the 330 included patients, 47 (14.2%) were found to have a germline mutation in BRCA1 or BRCA2. A positive HER2 receptor was associated with a lower likelihood of a BRCA1/2mutation (OR=0.125, 95% CI 0.016 to 0.955; P=0.007), while high-grade serous ovarian cancer was conversely associated with an increased likelihood of a BRCA1/2 mutation (OR=5.128, 95% CI 1.431 to 18.370; P=0.012). At the 10% threshold, 43.0% (142/330) of patients were indicated for testing under MSS3, compared with 35.8% (118/330) for MSS1% and 36.4% (120/330) for MSS2. At the 10% threshold, MSS3 sensitivity was 91.5% and specificity 65.0%, significantly better than the previous MSS1 (P=0.037) and MSS2 (P=0.032) models.

CONCLUSION

Our results indicate that the updated MSS3 outperforms previous iterations and relative to the Manchester population, is just as effective in identifying patients with BRCA1/2 mutations in a Southeast Asian population.

PPARγ Ligand-induced Annexin A1 Expression Determines Chemotherapy Response via Deubiquitination of Death Domain Kinase RIP in Triple-negative Breast Cancers

Metastatic breast cancer is still incurable so far; new specifically targeted and more effective therapies for triple-negative breast cancer (TNBC) are required in the clinic. In this study, our clinical data have established that basal and claudin-low subtypes of breast cancer (TNBC types) express significantly higher levels of Annexin A1 (ANXA1) with poor survival outcomes. Using human cancer cell lines that model the TNBC subtype, we observed a strong positive correlation between expression of ANXA1 and PPARγ. A similar correlation between these two markers was also established in our clinical breast cancer patients' specimens. To establish a link between these two markers in TNBC, we show de novo expression of ANXA1 is induced by activation of PPARγ both in vitro and in vivo and it has a predictive value in determining chemosensitivity to PPARγ ligands. Mechanistically, we show for the first time PPARγ-induced ANXA1 protein directly interacts with receptor interacting protein-1 (RIP1), promoting its deubiquitination and thereby activating the caspase-8-dependent death pathway. We further identified this underlying mechanism also involved a PPARγ-induced ANXA1-dependent autoubiquitination of cIAP1, the direct E3 ligase of RIP1, shifting cIAP1 toward proteosomal degradation. Collectively, our study provides first insight for the suitability of using drug-induced expression of ANXA1 as a new player in RIP1-induced death machinery in TNBCs, presenting itself both as an inclusion criterion for patient selection and surrogate marker for drug response in future PPARγ chemotherapy trials. Mol Cancer Ther; 16(11); 2528-42. ©2017 AACR.

Prevalence and Determinants of Adherence to Oral Adjuvant Endocrine Therapy among Breast Cancer Patients in Singapore

Objective:

The success of oral adjuvant endocrine therapy (OAET) is greatly influenced by patients’ level of adherence to treatment. The objective of this study is to measure the prevalence and determinants of adherence to OAET among breast cancer patients in Singapore.

Methods:

A cross-sectional survey of patients supplemented by analysis of their prescription records was used to collect data. Adherence to OAET was assessed using the Morisky Medication Adherence Scale-4 items and evaluation of refill gaps. Univariate and multivariate analyses were done to evaluate the association between patients’ characteristics and adherence to OAET.

Results:

A total of 157 women who have started OAET at least 6 months before the time of interview participated in the study, of which less than half (64 patients, 40.8%) of the patients had high adherence. Univariate analysis identified patients who were 57 years or older (P = 0.027), unemployed (P = 0.027), on aromatase inhibitors (P = 0.023), on three or more concurrent medications (P = 0.001), and had one or more comorbidities (P = 0.000) to be significantly more adherent. However, only the number of comorbidities was found to be an independent predictor of adherence in a multiple logistic regression analysis (adjusted odds ratio = 2.60; 95% confidence interval = 1.208–5.593; P = 0.015). Forgetfulness was the main reason for nonadherence mentioned by 63 (67.7%) of the 93 nonadherent patients.

Conclusions:

Low level of OAET adherence was found in this study, and forgetfulness was cited as the main reason for nonadherence. Patients were generally receptive to the implementation of various strategies to assist them with their medication-taking behavior

The Augmented Cognitive Mediation Model: Examining Antecedents of Factual and Structural Breast Cancer Knowledge Among Singaporean Women

As knowledge acquisition is an important component of health communication research, this study examines factors associated with Singaporean women's breast cancer knowledge using an augmented cognitive mediation model. We conducted a nationally representative study that surveyed 802 women between the ages of 30 and 70 using random-digit dialing. The results supported the augmented cognitive mediation model, which proposes the inclusion of risk perception as a motivator of health information seeking and structural knowledge as an additional knowledge dimension. There was adequate support for the hypothesized paths in the model. Risk perception was positively associated with attention to newspaper, television, Internet, and interpersonal communication. Attention to the three media channels was associated with interpersonal communication, but only newspaper and television attention were associated with elaboration. Interpersonal communication was positively associated with structural knowledge, whereas elaboration was associated with both factual and structural knowledge. Differential indirect effects between media attention and knowledge dimensions via interpersonal communication and elaboration were found. Theoretical and practical implications are discussed.

Barriers to early presentation of self-discovered breast cancer in Singapore and Malaysia: a qualitative multicentre study

OBJECTIVE

To explore and compare barriers to early presentation of self-discovered breast cancer in Singapore and Malaysia.

DESIGN

A qualitative interview study with thematic analysis of transcripts.

PARTICIPANTS

67 patients with self-discovered breast symptoms were included in the analysis. Of these, 36% were of Malay ethnicity, 39% were Chinese and 25% Indian, with an average age of 58 years (range 24-82 years). The number of women diagnosed at early stages of cancer almost equalled those at advanced stages. Approximately three-quarters presented with a painless lump, one-quarter experienced a painful lump and 10% had atypical symptoms.

SETTING

University hospital setting in Singapore and Malaysia.

RESULTS

Patients revealed barriers to early presentation not previously reported: the poor quality of online website information about breast symptoms, financial issues and the negative influence of relatives in both countries, while perceived poor quality of care and services in state-run hospitals and misdiagnosis by healthcare professionals were reported in Malaysia. The pattern of presentation by ethnicity remained unchanged where more Malay delayed help-seeking and had more advanced cancer compared to Chinese and Indian patients.

CONCLUSIONS

There are few differences in the pattern of presentation and in the reported barriers to seek medical care after symptom discovery between Singapore and Malaysia despite their differing economic status. Strategies to reduce delayed presentation are: a need to improve knowledge of disease, symptoms and causes, quality of care and services, and quality of online information; and addressing fear of diagnosis, treatment and hospitalisation, with more effort focused on the Malay ethnic group. Training is needed to avoid missed diagnoses and other factors contributing to delay among health professionals.

Characteristics and behaviour of screen-detected ductal carcinoma in situ of the breast: comparison with symptomatic patients

Breast cancer is the most common malignancy in Singapore women. Ductal carcinoma in situ (DCIS) is the putative, non-obligate precursor of the majority of invasive breast cancers. The efficacy of the Singapore breast-screening pilot project in detecting early stage breast cancer led to the launch of a national breast-screening programme, BreastScreen Singapore (BSS), in January 2002. In this study, we compared clinicopathological and immunohistochemical characteristics, as well as clinical outcomes, between screen-detected and symptomatic DCIS. The study cohort comprised 1202 cases of DCIS diagnosed at Singapore General Hospital from 1994 to 2010. Comparison of clinicopathological parameters, immunohistochemical results of ER, PR, HER2, CK14, EGFR, and 34βE12, and clinical outcomes was carried out between the 2 groups. Amongst 1202 cases, 610 (50.7%) were screen-detected and 592 (49.3%) were symptomatic DCIS. Screen-detected cases were smaller in size (P < 0.001), of lower nuclear grade (P = 0.004), and more frequently expressed ER (P < 0.001). Luminal A phenotype was more frequently observed in screen-detected DCIS, while triple-negative and HER2 phenotypes were more common in symptomatic DCIS (P < 0.001). The basal-like phenotype was also more frequent in symptomatic DCIS (P = 0.041). Mean and median follow-up was 99.7 and 97.8 months, respectively, with a maximum follow-up of 246.0 months. More symptomatic patients developed invasive recurrences compared to screen-detected patients (P = 0.001). A trend for better disease-free survival was observed in screen-detected patients (P = 0.076). Patients who were screen-detected experienced better overall survival than those with symptomatic DCIS (P = 0.007). Our data indicate a more favourable outcome of screen-detected DCIS patients confirming the role of BSS in early identification of this curable disease.

Temporal changes in breast cancer incidence in South Asian women

BACKGROUND

Breast cancer in the UK resident population of South Asian ethnicity has been lower than that in indigenous women. Leicester has a large South Asian population and a breast cancer unit with comprehensive data on diagnosed cancers. This study analysed the annual incidence of new breast cancer diagnoses in females from 1998 to 2009 to determine any changes in recent years.

METHODS

Ethnicity was known in over 98% of cases. Population denominators were based on published figures for 2001 and 2011, projected back to 1998. Age-adjusted directly standardised incidence rates were determined by ethnicity and broken down by invasive status and screening classification. Incidence rates were analysed using logistic regression in order to identify statistically significant effects of age, ethnicity, deprivation and year of diagnosis. Interactions with invasive status and screening classification were also investigated.

RESULTS

At the start of the study period South Asian incidence was estimated to be 45% of that of the white population (p<0.001); by the end of the period the difference was still significant (p=0.022) but smaller, at 17%.

CONCLUSION

South Asians should no longer be considered at low risk of breast cancer.

Contralateral prophylactic mastectomy in an Asian population: a single institution review

BACKGROUND

Contralateral prophylactic mastectomy (CPM) removes the non-diseased breast in women who have unilateral breast cancer. This reduces the incidence of contralateral breast cancer, and potentially improves survival in high risk patients. Such surgical risk-reduction strategy is increasingly being adopted in the United States, despite a decreasing incidence of contralateral breast cancer. The use of CPM in an Asian population is yet unknown. We present the first Asian report on CPM rates and trends in Singapore, the country with the highest incidence of breast cancer in Asia.

METHODS

A retrospective review of all patients who had breast cancer surgery from 2001 to 2010 at the largest healthcare system in Singapore was performed. Patient demographics and tumour characteristics were analysed with regards to type of surgery performed. Factors associated with CPM were identified.

RESULTS

From 2001 to 2010, a total of 5130 patients underwent oncological breast surgery. A decreasing trend of mastectomies (82.7%-70.8%), an upward trend of breast conserving surgery (BCS) (17.3%-29.2%) and an increasing trend in CPM (0.46%-1.25%) is observed. Patients who opted for CPM are likely to be younger (48.4 ± 9.4 years), married (60%), parous (56.7%), with no family history of breast/ovarian cancer (66.7%), and diagnosed at an earlier stage. The rate of synchronous occult breast malignancy was found to be 10% (n = 30), and these were in patients who were of a low cancer-risk profile.

CONCLUSIONS

This retrospective study reflects an increasing incidence of breast cancer in Singapore, with a decrease in mastectomies, and an increase in BCS and CPM rates, similar to Western data. Similar to Western populations, the Asian woman who opts for CPM is likely to be young and have an earlier stage of breast cancer. In contrast, the Asian woman is likely to have no family history of breast or ovarian cancers. Commonly cited reasons for increased CPM rates such as the increased availability of genetic counselling and pre-operative MRI evaluation, along with wide use of reconstruction, do not feature as dominant factors in our population, suggesting that the Asian patients may have different considerations when electing for CPM.

Time trends of cancer incidence in urban beijing, 1998-2007

OBJECTIVE

To report the time trends of cancer incidence in urban Beijing from 1998 to 2007.

METHODS

All data were obtained from Beijing Cancer Registry from 1998-2007 in urban Beijing. Time trends of incidence rate of cancer were assessed by annual percentage change (APC) of age-standardized incidence rate (ASR) of world standard population during this 10-year period.

RESULTS

For all 156851 cancer cases combined, the incidence rate rose in both males and females, with an APC of 2.23% and 3.74%, respectively. The incidence rate of upper gastrointestinal cancers declined significantly, with an APC of -2.83% in esophageal cancer and -1.37% in male gastric cancer, while lower gastrointestinal cancer, such as colorectal cancer, increased with an APC of 4.08%. The rates of kidney and bladder cancer increased with an APC of 7.93% and 5.57%, respectively. For women, the APC continued to rise in breast cancer (4.98%), ovary cancer (6.16%), cervix uteri cancer (11.74%), corpus uteri cancer (6.96%) and thyroid gland cancer (13.39%). The rate of prostate cancer among men increased with an APC of 8.58%; the rate of lymphoma and leukemia increased with APC of 5.48% and 5.44%, respectively.

CONCLUSION

Because of population aging and urban modernization, the cancer burden in Beijing has become more and more severe and similar to the western developed countries.

Supplementary Breast Ultrasound Screening in Asian Women with Negative But Dense Mammograms—A Pilot Study

Introduction: Dense breasts are common in Asian women and they limit the sensitivity of mammography. This study evaluates the performance of supplementary breast ultrasound screening in Asian women with dense mammograms. Materials and Methods: The study was approved by the hospital’s Institutional Review Board. A prospective clinical trial was performed between September 2002 and November 2004. Asymptomatic Asian women with negative and dense mammograms were offered supplementary ultrasound screening for breast cancer. Ultrasound assessment was categorised as U1 to U4. U1 and U2 cases were recommended routine interval screening mammography. U3 cases were recommended follow-up ultrasound in 6 months and routine interval screening mammography and U4 cases were recommended biopsy. Results: One hundred and forty-one women with mean age of 45.1 years were enrolled into the study. Mean scan time was 13.0 minutes (± 5.6 minutes) for bilateral vs 11.0 minutes (± 1.4 minutes) for unilateral scans. There were 10 patients and 14 patients in the in the U3 and U4 categories, respectively. Two U4 category patients were diagnosed with malignancy—a-6 mm ductal carcinoma-in-situ and a 13-mm invasive ductal carcinoma. The breast cancer detection rate was 1.4%. Sensitivity and specificity were 100% (2/2) and 88.5% (92/104) respectively. The positive predictive value was 14.3% (2/14) and the negative predictive value was 100% (92/92). Conclusion: This pilot study reveals the usefulness of supplementary ultrasound screening in detecting early stage mammographically and clinically occult breast cancers in Asian women with dense breasts. A larger long-term study is, however, needed to assess its feasibility and impact on breast cancer prognosis. Key words: Asian, Breast, Dense, Screening, Ultrasound

Measurement properties of the English and Chinese versions of the Functional Assessment of Cancer Therapy-Breast (FACT-B) in Asian breast cancer patients

The objective of the study was to examine the measurement properties of and comparability between the English and Chinese versions of the Functional Assessment of Cancer Therapy-Breast (FACT-B) in breast cancer patients in Singapore. This is an observational study of 271 Singaporean breast cancer patients. The known-group validity of FACT-B total score and Trial Outcome Index (TOI) were assessed in relation to performance status, evidence of disease, and treatment status cross-sectionally; responsiveness to change was assessed in relation to change in performance status longitudinally. Internal consistency and test-retest reliability were evaluated by the Cronbach's alpha and intraclass correlation coefficient (ICC), respectively. Multiple regression analyses were performed to compare the scores on the two language versions, adjusting for covariates. The FACT-B total score and TOI demonstrated known-group validity in differentiating patients with different clinical status. They showed high internal consistency and test-retest reliability, with Cronbach's alpha ranging from 0.87 to 0.91 and ICC ranging from 0.82 to 0.89. The English version was responsive to the change in performance status. The Chinese version was shown to be responsive to decline in performance status but the sample size of Chinese-speaking patients who improved in performance status was too small (N = 6) for conclusive analysis about responsiveness to improvement. Two items concerning sexuality had a high item non-response rate (50.2 and 14.4%). No practically significant difference was found in the total score and TOI between the two language versions despite minor differences in two of the 37 items. The English and Chinese versions of the FACT-B are valid, responsive, and reliable instruments in assessing health-related quality of life in breast cancer patients in Singapore. Data collected from the English and Chinese versions can be pooled and either version could be used for bilingual patients.

Quality of life in women during and after treatment for breast cancer: a systematic review of qualitative evidence

EXECUTIVE SUMMARY

Background Breast cancer is the most common cancer in women. With increasing numbers of women surviving breast cancer, there is a need to move beyond the traditional ways of evaluating clinical outcomes and include patient-based outcomes such as the quality of life.Objectives To integrate and summarise the best evidence related to the quality of life of women diagnosed with breast cancer during and up to ten years after treatment for breast cancer.

INCLUSION CRITERIA

Types of participants: Adult women (over the age of 18 years) diagnosed with breast cancer who are or have received treatment for breast cancer in the last ten years (i.e. surgery, chemotherapy, radiation therapy and/or hormonal therapy).

PHENOMENA OF INTEREST

The quality of life of women diagnosed with breast cancer during and up to ten years after treatment.

CONTEXT

Women with breast cancer from both developed and developing countries.Types of studies: Studies that focused on qualitative data including, but not limited to, designs such as phenomenology, grounded theory and ethnography, action research and feminist research.Search strategy The search sought to find both published and unpublished studies between 1990 and 2010, limited to the English language. Eleven electronic databases were searched including CINAHL, PubMed, Scopus and PsycArticles.Methodological quality Methodological quality was assessed independently by two reviewers using a standardised critical appraisal instrument from the Joanna Briggs Institute.Data extraction Qualitative data were extracted from the included studies using a standardised data extraction tool from the Joanna Briggs Institute.

RESULTS

A total of 42 findings from seven qualitative studies were extracted and rated as unequivocal or credible. Eleven categories were produced. Three synthesised findings were generated based on the meta-aggregation of the categories: (1) "effective care for patients will be achieved if clinicians are aware of the impact of breast cancer and its treatment on the physical and psychosocial domains of women's quality of life"; (2) "for effective patient-centred care, clinicians must be cognisant of the ways breast cancer and its treatment modalities affect social relationships"; (3) "clinicians should be aware that women use religion and spirituality to cope with breast cancer treatment and improve their quality of life".

CONCLUSIONS

This review concludes that the breast cancer diagnosis and its treatment can have a significant effect on several domains of women's quality of life. Healthcare providers caring for patients need to be well informed about each individual woman's physical and psychosocial concerns and be cognisant that any attempt to offer support must be targeted to meet the specific challenges faced by each individual woman.

IMPLICATIONS FOR PRACTICE

Support and guidance could be provided by healthcare providers through the use of counselling services, psycho-education and organisation of support groups. Elements of counselling and psycho-education should include, when appropriate, joint sessions with the woman's spouse/partner. As spirituality emerged as a coping mechanism, it is important that women be able to nurture their spiritual relationship in an environment which is supportive.

IMPLICATIONS FOR RESEARCH

The lack of studies within the Asian context indicates that further research is warranted to examine the impact of breast cancer and its treatment on the quality of life of women from diverse multi-ethnic populations. Further research into self-help strategies to improve the psychosocial well-being of women with breast cancer is warranted.It is noted that when faced with adversity, women seek comfort in religion and spirituality and a study into the relationship between spirituality and quality of life, as well as the effect of culture and religion on the quality of life, is warranted.

Recent trends and patterns in breast cancer incidence among Eastern and Southeastern Asian women

BACKGROUND

Incidence of breast cancer is rising in Asian countries, and breast cancer is the most common cancer among Asian women. However, there are few recent descriptive reports on the epidemiology of breast cancer among Eastern and Southeastern Asian populations.

METHODS

We examined incidence trends for invasive breast cancer in women aged ≥20 years from 15 registries in Eastern (China, Japan, the Republic of Korea, Taiwan) and Southeastern Asia (the Philippines, Singapore, Thailand) for the period 1993-2002 mainly using data from Cancer Incidence in Five Continents, Volumes VIII and IX. We compared trends in annual incidence rates and age-specific incidence curves over a 10-year period. We also compared the incidence rates of Asian-Americans with the rates of their Asian counterparts.

RESULTS

Breast cancer incidence rates increased gradually over time in all study populations. Rates were relatively high in Southeastern Asia and became progressively lower along a south-to-north gradient, with a fourfold geographic variation within the study populations. Age-specific incidence curves showed patterns that gradually changed according to incidence rates. Breast cancer incidence among Asian women living in the United States was 1.5-4 times higher than the corresponding incidence rate in the women's respective countries of origin.

CONCLUSION

Breast cancer incidence is expected to continue to increase for the next 10 years in Asia and may approach rates reported among Asian-Americans. The number and mean age of breast cancer cases is expected to increase as the female Asian population ages, the prevalence of certain risk factors changes (early menarche, late menopause, low parity, late age at first live birth, and low prevalence of breastfeeding), and as Asian countries introduce mass screening programs.

The hOGG1 Ser326Cys polymorphism and breast cancer risk: a meta-analysis

It was reported that the functional polymorphism Ser326Cys in the human 8-oxoguanine DNA glycosylase gene was associated with breast cancer risk; however, the published studies have inconsistent conclusions. To elucidate the effect of hOGG1 Ser326Cys on the susceptibility to breast cancer, all available studies were collected in this meta-analysis. We extracted the data from 10 case-control studies that were published in the PubMed database from 2003 to 2008 using the search phrases "human 8-oxoguanine DNA glycosylase, hOGG1, OGG1, OGG, polymorphism, genetic variation, and breast cancer." This meta-analysis included 4,963 breast cancer cases and 4,776 control subjects. The results showed that individuals who carrying the hOGG1 326Cys allele in the additive model did not have significantly increased risk of breast cancer compared with those carrying the 326Ser allele (P = 0.47, OR = 1.02; 95% CI = 0.96-1.09); similarly, no significant association between the hOGG1 326Cys allele and breast cancer risk was found either in the recessive genetic model (P = 0.34, OR = 1.06; 95% CI = 0.94-1.18) for Cys/Cys versus Ser/Cys + Ser/Ser, or dominant genetic model (P = 0.78, OR = 1.01; 95% CI = 0.93-1.11) for Cys/Cys + Ser/Cys versus Ser/Ser. In the stratified analysis, the meta-analysis showed the association between hOGG1 326Cys allele in the additive model and breast cancer was significant in European subjects (P = 0.04, OR = 0.71; 95% CI = 0.51-0.98), and dominant genetic model (P = 0.004, OR = 0.44; 95% CI = 0.25-0.77). However, the association was not significant between this polymorphism and different menopausal status (premenopausal and postmenopausal) and the other ethnicities (Asians and Americans). The meta-analysis suggested that the hOGG1 326Cys allele plays a significant protective effect to breast cancer in European women.