Breast cancer research in Asia: adopt or adapt Western knowledge?

Comprehensive genomic profiling and therapeutic implications for Taiwanese patients with treatment-naïve breast cancer

BACKGROUND

Breast cancer is a heterogeneous disease categorized based on molecular characteristics, including hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) expression levels. The emergence of profiling technology has revealed multiple driver genomic alterations within each breast cancer subtype, serving as biomarkers to predict treatment outcomes. This study aimed to explore the genomic landscape of breast cancer in the Taiwanese population through comprehensive genomic profiling (CGP) and identify diagnostic and predictive biomarkers.

METHODS

Targeted next-generation sequencing-based CGP was performed on 116 archived Taiwanese breast cancer specimens, assessing genomic alterations (GAs), including single nucleotide variants, copy number variants, fusion genes, tumor mutation burden (TMB), and microsatellite instability (MSI) status. Predictive variants for FDA-approved therapies were evaluated within each subtype.

RESULTS

In the cohort, frequent mutations included PIK3CA (39.7%), TP53 (36.2%), KMT2C (9.5%), GATA3 (8.6%), and SF3B1 (6.9%). All subtypes had low TMB, with no MSI-H tumors. Among HR + HER2- patients, 42% (27/65) harbored activating PIK3CA mutations, implying potential sensitivity to PI3K inhibitors and resistance to endocrine therapies. HR + HER2- patients exhibited intrinsic hormonal resistance via FGFR1 gene gain/amplification (15%), exclusive of PI3K/AKT pathway alterations. Aberrations in the PI3K/AKT/mTOR and FGFR pathways were implicated in chemoresistance, with a 52.9% involvement in triple-negative breast cancer. In HER2+ tumors, 50% harbored GAs potentially conferring resistance to anti-HER2 therapies, including PIK3CA mutations (32%), MAP3K1 (2.9%), NF1 (2.9%), and copy number gain/amplification of FGFR1 (18%), FGFR3 (2.9%), EGFR (2.9%), and AKT2 (2.9%).

CONCLUSION

This study presents CGP findings for treatment-naïve Taiwanese breast cancer, emphasizing its value in routine breast cancer management, disease classification, and treatment selection.

High-value breast cancer care within resource limitations

Breast cancer care is a costly global health issue where effective management depends on early detection and treatment. A breast cancer diagnosis can result in financial catastrophe especially in low- and middle-income countries (LMIC). Large inequities in breast cancer care are observed and represent a global challenge to caregivers and patients. Strategies to improve early diagnosis include awareness and clinical breast examination in LMIC, and screening in high-income countries (HIC). The use of clinical guidelines for the management of breast cancer is needed. Adapted guidelines from HIC can address disparities in populations with limited resources. Locally developed strategies still provide effective guidance in improving survival. Integrated practice units (IPU) with timely multidisciplinary breast care conferences and patient navigators are required to achieve high-value, personalized breast cancer management in HIC as well as LMIC. Breast cancer patient care should include a quality of life evaluation using ideally patient-reported outcomes (PROM) and experience measurements (PREM). Evaluation of breast cancer outcomes must include the financial cost of delivered care. The resulting value perspective should guide resource allocation and program priorities. The value of care must be improved by translating the findings of social and economic research into practice and resolving systemic inequity in clinical breast cancer research. Cancer survivorship programs must be put in place everywhere. The treatment of patients with metastatic breast cancer must require more attention in the future, especially in LMIC.

Age-specific breast and ovarian cancer risks associated with germline BRCA1 or BRCA2 pathogenic variants - an Asian study of 572 families

Background

Clinical management of Asian BRCA1 and BRCA2 pathogenic variants (PV) carriers remains challenging due to imprecise age-specific breast (BC) and ovarian cancer (OC) risks estimates. We aimed to refine these estimates using six multi-ethnic studies in Asia.

Methods

Data were collected on 271 BRCA1 and 301 BRCA2 families from Malaysia and Singapore, ascertained through population/hospital-based case-series (88%) and genetic clinics (12%). Age-specific cancer risks were estimated using a modified segregation analysis method, adjusted for ascertainment.

Findings

BC and OC relative risks (RRs) varied across age groups for both BRCA1 and BRCA2. The age-specific RR estimates were similar across ethnicities and country of residence. For BRCA1 carriers of Malay, Indian and Chinese ancestry born between 1950 and 1959 in Malaysia, the cumulative risk (95% CI) of BC by age 80 was 40% (36%-44%), 49% (44%-53%) and 55% (51%-60%), respectively. The corresponding estimates for BRCA2 were 29% (26-32%), 36% (33%-40%) and 42% (38%-45%). The corresponding cumulative BC risks for Singapore residents from the same birth cohort, where the underlying population cancer incidences are higher compared to Malaysia, were higher, varying by ancestry group between 57 and 61% for BRCA1, and between 43 and 47% for BRCA2 carriers. The cumulative risk of OC by age 80 was 31% (27-36%) for BRCA1 and 12% (10%-15%) for BRCA2 carriers in Malaysia born between 1950 and 1959; and 42% (34-50%) for BRCA1 and 20% (14-27%) for BRCA2 carriers of the same birth cohort in Singapore. There was evidence of increased BC and OC risks for women from >1960 birth cohorts (p-value = 3.6 × 10-5 for BRCA1 and 0.018 for BRCA2).

Interpretation

The absolute age-specific cancer risks of Asian carriers vary depending on the underlying population-specific cancer incidences, and hence should be customised to allow for more accurate cancer risk management.

Funding

Wellcome Trust [grant no: v203477/Z/16/Z]; CRUK (PPRPGM-Nov20∖100002).

Clinical characteristics and pathologic complete response (pCR) rate after neoadjuvant chemotherapy in postpartum women with breast cancer

PURPOSE

Breast cancer (BC) is currently the leading cause of death in women worldwide. Studies have confirmed that pregnancy is an independent factor affecting the survival of BC patients. BC found during pregnancy, lactation, or shortly after delivery is what we used to think of as pregnancy-associated breast cancer (PABC). The current expert definition of this concept is not uniform; however, there is growing evidence that postpartum breast cancer (PPBC) differs from other types of BC in terms of both biological features and prognosis, with a slightly different focus on diagnosis and treatment. With the increase of female reproductive age population and changes in fertility policies in China, patients with PPBC are receiving increasing attention. Here, we systematically analyzed the clinicopathological characteristics and chemotherapeutic response of patients with PPBC. We retrospectively analyzed the clinicopathological data, molecular subtypes, chemotherapy regimens, and pathological complete remission (pCR) rates of 1343 patients with non-metastatic BC at Harbin Medical University Cancer Hospital from January 1, 2012 to May 31, 2023. The categorical data were compared by chi-square test and Fisher exact test using logistic regression model. Predictor variables with P < 0.05 in the univariate analysis were included in the multivariate regression analysis to investigate the relationship between different age groups and pCR.

RESULTS

A total of 714 patients were eligible for analysis in this study, and 667 patients had a history of pregnancy, 40 (5.6%) of whom were PPBC patients. When diagnosed with BC, patients with PPBC were younger, more likely to undergo breast-conserving surgery (BCS), and more likely to achieve pCR (P < 0.05). In molecular typing, human epidermal growth factor receptor 2 (HER-2)-positive and triple-negative breast cancer (TNBC) were more frequent. In the entire cohort, HER-2 expression and delivery status were independent predictors of pCR rates in BC patients after neoadjuvant chemotherapy (NAC).

CONCLUSION

Our findings suggest that postpartum status is an independent predictor of pCR attainment in BC patients. PPBC is more sensitive to chemotherapy than other patients.We need to pay more attention to this group and achieve individualized treatment, which will help us treat BC better and provide new targets and blueprints for our clinical therapy.

Family history and breast cancer risk for Asian women: a systematic review and meta-analysis

BACKGROUND

Studies of women of European ancestry have shown that the average familial relative risk for first-degree relatives of women with breast cancer is approximately twofold, but little is known for Asian women. We aimed to provide evidence for the association between family history and breast cancer risk for Asian women by systematically reviewing published literature.

METHODS

Studies reporting the familial relative risk of breast cancer for Asian women were searched in three online databases and complemented by a manual search. Odds ratios (ORs) for the association between family history and breast cancer risk were pooled across all included studies and by subgroups in terms of the type of family history, age, menopausal status and geographical region.

RESULTS

The pooled OR for women who have a first-degree relative with breast cancer was 2.46 (95% confidence interval [CI]: 2.03, 2.97). There was no evidence that the familial risk differed by the type of affected relative (mother versus sisters), the woman's age (< 50 years versus ≥ 50 years), menopausal status (pre versus post) and geographical region (East and Southeast Asia versus other regions) (all P > 0.3). The pooled ORs for women of Asian ancestry with a family history in any relative were similar for those living in non-Asian countries (2.26, 95% CI: 1.42, 3.59) compared with those living in Asian countries (2.18, 95% CI: 1.85, 2.58).

CONCLUSIONS

Family history of breast cancer is associated with an approximately twofold relative risk of breast cancer for Asian women, which is of similar magnitude to that observed for women of European ancestry. This implies that similar familial factors are implicated in breast cancer risk between women of European and Asian ancestries. Genetic factors are likely to play a substantial role in explaining the breast cancer familial risk for Asian women, as similar risks were observed across different living environments and cultures.

Will Absolute Risk Estimation for Time to Next Screen Work for an Asian Mammography Screening Population?

Personalized breast cancer risk profiling has the potential to promote shared decision-making and improve compliance with routine screening. We assessed the Gail model's performance in predicting the short-term (2- and 5-year) and the long-term (10- and 15-year) absolute risks in 28,234 asymptomatic Asian women. Absolute risks were calculated using different relative risk estimates and Breast cancer incidence and mortality rates (White, Asian-American, or the Singapore Asian population). Using linear models, we tested the association of absolute risk and age at breast cancer occurrence. Model discrimination was moderate (AUC range: 0.580-0.628). Calibration was better for longer-term prediction horizons (E/O_{long-term ranges}: 0.86-1.71; E/O_{short-term ranges}:1.24-3.36). Subgroup analyses show that the model underestimates risk in women with breast cancer family history, positive recall status, and prior breast biopsy, and overestimates risk in underweight women. The Gail model absolute risk does not predict the age of breast cancer occurrence. Breast cancer risk prediction tools performed better with population-specific parameters. Two-year absolute risk estimation is attractive for breast cancer screening programs, but the models tested are not suitable for identifying Asian women at increased risk within this short interval.

Benefits of PECS Block as Part of the Enhanced Recovery After Surgery (ERAS) Protocol for Breast Cancer Surgery in an Asian Institution: A Retrospective Cohort Study

INTRODUCTION

Regional analgesia techniques have been increasingly used for post-operative pain management following mastectomy. We aim to evaluate analgesic benefits of pectoral nerve (PECS2) block incorporated as part of the enhanced recovery after surgery (ERAS) protocol in patients undergoing mastectomy in University Malaya Medical Centre, Malaysia.

MATERIAL AND METHODS

A single centre, cohort study evaluating 335 women who have undergone unilateral mastectomy between January 2017 and March 2020 in Malaysia. Regional anaesthesia were given pre-operatively via ultrasound guided pectoral and intercostal nerves block (PECSII).

RESULTS

Utilization of regional anaesthesia increased from 11% in 2017 to 43% in 2020. Types and duration of surgeries were comparable. Opiod consumption was 3 mg lower in those who had PECS2 block ((27 [24-30] mg), in comparison with those who received general anaesthesia only (30 [26-34] mg), p < 0.001, and length of stay was half a day shorter in the regional anaesthesia group and these were statistically significant. However, pain score (2 [1-3]; 2 [1-3], p=0.719) and post-operative nausea and vomiting (PONV) (32.6-32.5%, p = 0.996) were similar.

CONCLUSION

This study highlights the importance of PECS2 block as a component of ERAS protocol for mastectomy in an Asian hospital. This study also inferred that patients may be safely discharged within 24 h of surgery and therefore, same day surgery may be feasible in selected group of patients undergoing mastectomy and this could imply overall cost benefits.

Look how far we have come: BREAST cancer detection education on the international stage

The development of screening mammography over 30 years has remarkedly reduced breast cancer-associated mortality by 20%-30% through detection of small cancer lesions at early stages. Yet breast screening programmes may function differently in each nation depending on the incidence rate, national legislation, local health infrastructure and training opportunities including feedback on performance. Mammography has been the frontline breast cancer screening tool for several decades; however, it is estimated that there are 15% to 35% of cancers missed on screening which are owing to perceptual and decision-making errors by radiologists and other readers. Furthermore, mammography screening is not available in all countries and the increased speed in the number of new breast cancer cases among less developed countries exceeds that of the developed world in recent decades. Studies conducted through the BreastScreen Reader Assessment Strategy (BREAST) training tools for breast screening readers have documented benchmarking and significant variation in diagnostic performances in screening mammogram test sets in different countries. The performance of the radiologists from less well-established breast screening countries such as China, Mongolia and Vietnam were significant lower in detecting early-stage cancers than radiologists from developed countries such as Australia, USA, Singapore, Italy. Differences in breast features and cancer presentations, discrepancies in the level of experiences in reading screening mammograms, the availability of high-quality national breast screening program and breast image interpretation training courses between developed and less developed countries are likely to have impact on the variation of readers' performances. Hence dedicated education training programs with the ability to tailor to different reader cohorts and different population presentations are suggested to ameliorate challenges in exposure to a range of cancer cases and improve the interpretation skills of local radiologists. Findings from this review provide a good understanding of the radiologist' performances and their improvement using the education interventions, primarily the BREAST program, which has been deployed in a large range of developing and developed countries in the last decade. Self-testing and immediate feedback loops have been shown to have important implications for benchmarking and improving the diagnostic accuracy in radiology worldwide for better breast cancer control.

Breast Cancer in Asia: Incidence, Mortality, Early Detection, Mammography Programs, and Risk-Based Screening Initiatives

Simple Summary

Nearly all breast cancer patients survive for more than five years when the tumor is found early and in the localized stage. Regular clinical breast examinations, mammograms, and monthly self-exams of the breasts all contribute to early detection. However, late-stage breast cancers are common in many Asian countries. Low-income countries suffer from a lack of resources for breast cancer screening. High-income countries, on the other hand, are not benefiting fully from national breast screening programs due to an underutilization of the preventive healthcare services available. Existing reviews on Asian breast cancers are heavily focused on risk factors. The question of whether we should adopt or adapt the knowledge generated from non-Asian breast cancers would benefit from an extension into screening guidelines. In addition, several Asian countries are piloting studies that move away from the age-based screening paradigm.

Abstract

Close to half (45.4%) of the 2.3 million breast cancers (BC) diagnosed in 2020 were from Asia. While the burden of breast cancer has been examined at the level of broad geographic regions, literature on more in-depth coverage of the individual countries and subregions of the Asian continent is lacking. This narrative review examines the breast cancer burden in 47 Asian countries. Breast cancer screening guidelines and risk-based screening initiatives are discussed.

An Integrated Machine Learning Scheme for Predicting Mammographic Anomalies in High-Risk Individuals Using Questionnaire-Based Predictors

This study aimed to investigate the important predictors related to predicting positive mammographic findings based on questionnaire-based demographic and obstetric/gynecological parameters using the proposed integrated machine learning (ML) scheme. The scheme combines the benefits of two well-known ML algorithms, namely, least absolute shrinkage and selection operator (Lasso) logistic regression and extreme gradient boosting (XGB), to provide adequate prediction for mammographic anomalies in high-risk individuals and the identification of significant risk factors. We collected questionnaire data on 18 breast-cancer-related risk factors from women who participated in a national mammographic screening program between January 2017 and December 2020 at a single tertiary referral hospital to correlate with their mammographic findings. The acquired data were retrospectively analyzed using the proposed integrated ML scheme. Based on the data from 21,107 valid questionnaires, the results showed that the Lasso logistic regression models with variable combinations generated by XGB could provide more effective prediction results. The top five significant predictors for positive mammography results were younger age, breast self-examination, older age at first childbirth, nulliparity, and history of mammography within 2 years, suggesting a need for timely mammographic screening for women with these risk factors.

Impact of the ACOSOG Z0011 trial on surgical practice in Asian patients: trends in axillary surgery for breast cancer from a Korean Breast Cancer Registry analysis

Background

Since the publication of the Z0011 trial, practice-changing clinical guidelines for breast surgery have been developed. Although recent studies confirmed the feasibility of the Z0011 strategy in Asian populations, there has been no study on the trends of axillary surgery in Asian cohort. This study aimed to investigate the time trend of axillary surgery for breast cancer from a Korean Breast Cancer Registry to understand the impact of the Z0011 trial in Asian patients.

Methods

We collected prospectively constructed data from the nationwide Korean Breast Cancer Registry (KBCR). We identified patients who underwent sentinel node biopsy followed by breast-conserving surgery from 2011 to 2018 and were found to have pathological stage T1-2N1-3M0 disease. Regression analyses were performed to compare the downward trend of axillary lymph node dissection (ALND) in Korean cohort with that previously reported in a Dutch cohort.

Results

From KBCR data, 7478 patients met the inclusion criteria. The proportion of ALND significantly decreased from 2011 (76.6%) to 2018 (47.5%). Multivariate analysis revealed that earlier years at diagnosis, larger tumor size, and lymphatic invasion were associated with a higher odds ratio of performing ALND. Compared to the Dutch cohort, the downward trend of ALND in Korea was significantly more gradual (annual percent change: 37.2 vs. 5.8%, p < 0.001).

Conclusions

This study demonstrated a downward trend of ALND in Korean patients with breast cancer. However, the rate of decrease was significantly slower than that in the Dutch cohort.

Racial differences in predictive value of the 21-gene recurrence score assay: a population-based study using the SEER database

Purpose

The 21-gene recurrence score (RS) assay is currently used for predicting chemotherapeutic benefits for hormone receptor-positive (HR +) early-stage breast cancer patients without consideration regarding racial differences in that predictive value. This study aimed at demonstrating racial differences in the predictive values of the 21-gene RS assay.

Methods

The study cohort was selected from the Surveillance, Epidemiology, and End Results (SEER) database. Breast cancer-specific mortality (BCSM) was compared between patients who received chemotherapy (the “CTx group”) and those who did not (the “no CTx group”) to estimate the predictive value of the assay. This comparison was repeated for each racial group.

Results

Among 88,498 T1 − 2N0 HR + breast cancer patients who had results of 21-gene RS, 13,123 patients had RS > 25, which included 10,697 Whites, 1282 Blacks, and 1,144 Asian Americans/Pacific Islanders (AAPIs). Chemotherapy was administered to 8364 patients (63.4%). The adjusted hazard ratio for BCSM in the CTx group (vs. no CTx group) was 0.734 (95% confidence interval [CI] 0.588–0.917) in Whites, 0.748 (95% CI 0.428–1.307) in Blacks, and 1.343 (95% CI 0.558–3.233) in AAPIs. No subgroup within patients with RS > 25 among non-White women showed a significant predictive value of the 21-gene RS assay, except for Black women with grade 3 tumors.

Conclusion

The predictive value of the 21-gene RS assay for assessing chemotherapy benefit was validated in White women based on the SEER database, although the predictive value was not warranted in non-White women.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12282-022-01371-z.

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.

Moderation effect of mammography screening among women with multiple chronic conditions

Comorbidity substantially affects breast cancer risk and prognosis. However, women with chronic conditions are less likely to participate in mammography screening. Few studies have examined potential benefits of mammography in women with chronic conditions. This study investigated the moderation effects of mammography screening on early stage breast cancer and all-cause mortality among women aged 50–69 years with chronic conditions in Taiwan. We used a matched cohort design with four nationwide population databases, and an exact matching approach to match groups with different chronic conditions. Women population aged 50–69 years in 2010 in Taiwan were studied. A generic Charlson comorbidity index (CCI) measure was used to identify chronic illness burden. The sample sizes of each paired matched group with CCI scores of 0, 1, 2, or 3+ were 170,979 using a 1-to-1 exact matching. Conditional logistic regressions with interaction terms were used to test moderation effect, and adjusted predicted probabilities and marginal effects to quantify average and incremental chronic conditions associated with outcome measures. Statistical analyses were conducted in 2020–2021. Women with more chronic conditions were less likely to participate in mammography screening or to receive early breast cancer diagnoses, but were at greater risk of mortality. However, mammography participation increased the likelihood of early breast cancer diagnosis (OR 1.48, 95% CI 1.36–1.60) and decreased risk of all-cause mortality (HR 0.53, 95% CI 0.51–0.55). The interaction terms of CCI and mammography participation indicated significantly increased benefits of early breast cancer diagnosis and decreased risk of all-cause mortality as chronic illness increased. Mammography participation significantly moderated the link between comorbidity and outcome measures among women with chronic conditions. Hence, it is important for public health policy to promote mammography participation for women with multiple chronic conditions.

Prevalence of breast imaging reporting and data system (BIRADS) categories and breast consistencies in Central India -A cross-sectional survey

Background:

For recognizing the initial stages of breast cancer, mammography is regarded as one of the best modalities and plays a crucial part to lessen morbidity and mortality. For collaborative studies and planning of preventive strategies, it is significant to have baseline data. Thus, in this survey, the frequency distribution of breast imaging reporting and data system (BIRADS) classification and breast consistencies was investigated during the mammographic screening program in the Gwalior region, India.

Material and Methods:

A descriptive, cross-sectional survey was conducted in the Gwalior region, India, in which 1,838 patients were screened with the aid of mammography. The mammography films were evaluated by a single radiologist who determined the BIRADS score, breast composition, and any other abnormal findings. After tabulating the data into MS Excel (MS Office version 2007 developed by Microsoft, Redmond, WA), descriptive analysis and Chi-square test were performed to determine the association between the BIRADS score and breast consistency and setting significance level at (below) 0.05.

Results:

The most commonly found BIRADS score was score 1 (53.4%), followed by score 2 (20.4%), and score 5 was of the least frequency (1.3%). Similarly, the most common consistency found was fatty (48.2%) and the least common was heterogeneously dense (3.97%). The most BIRADS category of 0 was seen in heterogeneously dense (n = 22; 26%) followed by dense breast compositions (n = 18; 25%). The most common consistency found with known breast malignancy (BIRADS 6) patients was the extremely dense breast (n = 11; 40.7%).

Conclusion:

In this study, it was observed that about 57.3% of all the cases were categorized as BIRADS 1 and 20.8% as BIRADS 2.

An Overview of the Treatment Efficacy and Side Effect Profile of Pharmacological Therapies in Asian Patients with Breast Cancer

Breast cancer (BC) among Asians accounts for ~ 40% of the global BC burden. Differences in BC risk, presentation, tumor biology, and response to treatment exist between Asian and non-Asian patients; however, Asian patients are often under-represented in clinical trials. This narrative review summarizes the efficacy and safety of pharmacological therapies for BC in Asian populations, with a focus on outcomes in Asian versus non-Asian patients treated with chemotherapy, hormone therapy, anti-human epidermal growth factor receptor-2 targeted therapies, cyclin-dependent kinase 4/6 (CDK4/6) inhibitors, mammalian target of rapamycin inhibitors, bone-targeted therapies, poly-ADP ribose polymerase, phosphoinositide 3-kinase, and checkpoint inhibitors. While most therapies have demonstrated comparable efficacy and safety in Asian and non-Asian patients with BC, differences that are largely attributed to pharmacogenetic variations between populations exist. Pharmacogenetic differences may contribute to a reduced clinical benefit of tamoxifen, whereas improved clinical outcomes have been reported with tyrosine kinase inhibitors and CDK4/6 inhibitors in Asian versus non-Asian patients with BC. In particular, Asian patients have an increased incidence of hematological toxicities, including neutropenia, although adverse events can be effectively managed using dose adjustments. Recent trials with CDK4/6 inhibitors have increased efforts to include Asians within study subsets. Future clinical trials enrolling higher numbers of Asian patients, and an increased understanding of differences in patient and tumor genetics between Asians and non-Asians, have the potential to incrementally improve the management of BC in Asian patients.

Breast cancer risk stratification for mammographic screening: A nation-wide screening cohort of 24,431 women in Singapore

Background

Breast cancer incidence is increasing in Asia. However, few women in Singapore attend routine mammography screening. We aim to identify women at high risk of breast cancer who will benefit most from regular screening using the Gail model and information from their first screen (recall status and mammographic density).

Methods

In 24,431 Asian women (50–69 years) who attended screening between 1994 and 1997, 117 developed breast cancer within 5 years of screening. Cox proportional hazard models were used to study the associations between risk classifiers (Gail model 5‐year absolute risk, recall status, mammographic density), and breast cancer occurrence. The efficacy of risk stratification was evaluated by considering sensitivity, specificity, and the proportion of cancers identified.

Results

Adjusting for information from first screen attenuated the hazard ratios (HR) associated with 5‐year absolute risk (continuous, unadjusted HR [95% confidence interval]: 2.3 [1.8–3.1], adjusted HR: 1.9 [1.4–2.6]), but improved the discriminatory ability of the model (unadjusted AUC: 0.615 [0.559–0.670], adjusted AUC: 0.703 [0.653–0.753]). The sensitivity and specificity of the adjusted model were 0.709 and 0.622, respectively. Thirty‐eight percent of all breast cancers were detected in 12% of the study population considered high risk (top five percentile of the Gail model 5‐year absolute risk [absolute risk ≥1.43%], were recalled, and/or mammographic density ≥50%).

Conclusion

The Gail model is able to stratify women based on their individual breast cancer risk in this population. Including information from the first screen can improve prediction in the 5 years after screening. Risk stratification has the potential to pick up more cancers.

Talazoparib Versus Chemotherapy in Patients with HER2-negative Advanced Breast Cancer and a Germline BRCA1/2 Mutation Enrolled in Asian Countries: Exploratory Subgroup Analysis of the Phase III EMBRACA Trial

PURPOSE

We evaluated study outcomes in patients enrolled in Asian regions in the phase III EMBRACA trial of talazoparib vs. chemotherapy.

MATERIALS AND METHODS

Patients with human epidermal growth factor receptor 2-negative germline BRCA1/2-mutated advanced breast cancer who received prior chemotherapy were randomized 2:1 to talazoparib 1 mg/day or chemotherapy (physician's choice). Primary endpoint was progression-free survival (PFS) per independent central review in the intent-to-treat (ITT) population. This post-hoc analysis evaluated efficacy/safety endpoints in the ITT population of patients enrolled in Asian regions.

RESULTS

Thirty-three patients were enrolled at Asian sites (talazoparib, n=23; chemotherapy, n=10). Baseline characteristics were generally comparable with the overall EMBRACA population. In Asian patients, median PFS was 9.0 months (95% confidence interval [CI], 3.0 to 15.2) for talazoparib and 7.1 months (95% CI, 1.2 to not reached) for chemotherapy (hazard ratio [HR], 0.74 [95% CI, 0.22 to 2.44]). Objective response rate was numerically higher for talazoparib vs. chemotherapy (62.5% [95% CI, 35.4 to 84.8] vs. 25.0% [95% CI, 3.2 to 65.1]). Median overall survival was 20.7 months (95% CI, 9.4 to 40.1) versus 21.2 months (95% CI, 2.7 to 35.0) (HR, 1.41 [95% CI, 0.49 to 4.05]). In Asian patients, fewer grade 3/4 adverse events (AEs), serious AEs (SAEs), grade 3/4 SAEs, and AEs resulting in dose reduction/discontinuation occurred with talazoparib than chemotherapy; for talazoparib, the frequency of these events was lower in Asian patients versus overall EMBRACA population.

CONCLUSION

In this subgroup analysis, talazoparib numerically improved efficacy versus chemotherapy and was generally well tolerated in Asian patients, with fewer grade 3/4 treatment-emergent AE (TEAEs), SAEs, and TEAEs leading to dose modification vs. the overall EMBRACA population.

Mediation Effect of Health Beliefs in the Relationship Between Health Knowledge and Uptake of Mammography in a National Breast Cancer Screening Program in Taiwan

Despite evidence that breast cancer screening effectively diagnoses and treats cancer through early detection, mammography use remains low in Taiwan. We applied the health belief model (HBM) and the knowledge-attitude-behavior (KAB) model as theoretical frameworks to examine factors associated with mammography uptake among women aged 45-69 years in Taiwan. A cross-sectional survey January-July 2018 was conducted of women aged 45-69 years in five southern Taiwan health institutions. Survey questionnaires included demographics, HBM constructs, and health knowledge regarding breast cancer and screening. Multivariable logistic regression models explored the mediation effects of HBM constructs between health knowledge and mammography use. The final analytical sample included 621 women; 67 did not receive mammography and 554 received mammography. When the regression model was adjusted only for demographic factors, women with adequate health knowledge were more likely to undergo mammography (AOR = 2.321, 95%CI = 1.141-3.809); in regression models including health knowledge and HBM constructs, the likelihood effect of health knowledge declined and became insignificant (AOR = 1.711, 95%CI = 0.985-2.972), indicating potential mediation effects between health knowledge and up-to-date mammography use. Overall, based on the HBM and the KAB theoretical framework, our data support that health belief played a substantial mediating role in the association between health knowledge and mammography uptake, in particular perceived barriers and cues to action in the HBM, which were modifying factors of health beliefs. Therefore, to improve mammography uptake, it may be helpful to design educational model-based interventions through tackling those modifiable perceived barriers and enhancing the intensity of external cues to action.

Risk evaluation of early-stage hormone receptor-positive and human epidermal growth factor receptor 2-negative breast cancer patients: a population-based study from Taiwan

PURPOSE

To assess the prognostic value of the Dutch criteria for patients with early-stage hormone receptor-positive and human epidermal growth factor receptor 2-negative breast cancer from the Taiwan Cancer Registry Database.

PATIENTS AND METHODS

We included 8295 patients with early-stage node-negative breast cancer who underwent surgery during January 2008-December 2012. Patients were stratified into low- and high-risk groups based on the Dutch criteria. The Kaplan-Meier method and log-rank test were used to estimate the difference in breast cancer-specific survival (BCSS) and overall survival (OS) between groups. Multivariable analysis was used to evaluate the prognostic value of the Dutch criteria.

RESULTS

Overall, the low-risk and high-risk groups comprised 5375 and 2920 patients, respectively. In the low- and high-risk groups, the 5-year BCSS rate was 99.6% and 98.2% (P < 0.0001) and the 5-year OS rate was 98.3% and 96.8% (P < 0.0001), respectively. The hazard ratio for BCSS was 4.18 (95% confidence interval [CI] 2.63-6.63, P < 0.0001), and the hazard ratio for OS was 1.94 (95% CI 1.48-2.55); both were significantly poorer in the high-risk group than in the low-risk group. In the low-risk group, the 5-year BCSS and OS of patients who did and did not receive adjuvant chemotherapy were similar (99.5% versus 99.6% [P = 0.927] and 98.8% and 98.1% [P = 0.0683], respectively).

CONCLUSION

The prognosis of low-risk patients as classified using the Dutch criteria is excellent with or without adjuvant chemotherapy. The benefit of multi-gene testing for chemotherapy decision-making might be minimal in these patients.

Effect of accessibility improvement in a national population-based breast cancer screening policy on mammography utilization among women with comorbid conditions in Taiwan

In Taiwan, a Cancer Screening Quality Improvement Program (CAQIP), implemented in 2010, provides financial support to qualified hospitals to improve accessibility. This study aimed to examine the effect of CAQIP on mammography participation among women aged 50-69 years at various health statuses. A natural experimental study design before and after CAQIP implementation in 2010 was conducted. Phase 1 included 437,875 screened and 1,490,453 non-screened women, and 830,348 and 1,03,454 in Phase 2. Compared with women with no comorbidity, women with severe chronic conditions were less likely to participate in mammography screening. CAQIP was positively associated with the likelihood of mammography participation (OR 3.899, 95% CI 3.878-3.920); the magnitude of the effect was smaller for women with comorbid conditions. The findings provide evidences and economic theorical perspectives of potential benefits of health policy interventions to improve accessibility and mammography participation among women aged 50-69 years with comorbid conditions.

Breast cancer in elderly Korean women: clinicopathological and biological features

BACKGROUND

With an aging society, Korean women ≥70 years of age are increasingly being diagnosed with breast cancer.

OBJECTIVE

To investigate the clinicopathological and biological characteristics of breast cancer in elderly Korean women and compare them with breast cancer in elderly (≥70 years) women globally and in Korean women of all ages.

METHODS

We retrospectively reviewed the clinicopathological and biological features of breast cancer in elderly Korean women (≥70 years; n = 87) who sought treatment during 2004-2014 from a single institution. These data were indirectly compared with data of Korean women of all ages (nationwide Korean Breast Cancer Registry) or elderly women globally (meta-analysis).

RESULTS

Compared to elderly women with breast cancer globally, Korean elderly women had a more symptomatic presentation, lower ER expression, and overexpression or amplification of human epidermal growth factor receptor 2. Compared to Korean women of all ages with breast cancer, elderly Korean women presented with advanced tumor stages, larger tumor size, more lymph node involvement, and more luminal B and basal-like subtypes.

CONCLUSIONS

Breast cancer had a more aggressive clinicopathological and biological characteristics in elderly Korean women than in Korean women of all ages or elderly women globally.

Cohort profile: The Singapore Breast Cancer Cohort (SGBCC), a multi-center breast cancer cohort for evaluation of phenotypic risk factors and genetic markers

This article aims to provide a detailed description of the Singapore Breast Cancer Cohort (SGBCC), an ongoing multi-ethnic cohort established with the overarching goal to identify genetic markers for breast cancer risk, prognosis and treatment response, as well as to understand the ethnic differences in disease risk and outcome in an Asian setting. The cohort comprises of breast cancer patients aged 21 years and above from six public hospitals which diagnose and treat nearly 76% breast cancer cases in Singapore. Self-reported data on sociodemographic and lifestyle, reproductive risk factors, medical history and family history of breast or ovarian cancer is collected using a structured questionnaire. Clinical data on tumour characteristics, and treatment modalities are obtained through medical record. Bio-specimens (blood or saliva) is collected at recruitment. Follow-up on survival information is done through routine linkage with the Registry of Births and Deaths. As of 31 December 2016, 7,768 subjects have been recruited to the study with 76% subjects contributed bio-specimens. The SGBCC provides a valuable platform which offers a unique, large and rich resource for new research ideas on breast cancer related phenotypic risk factors and genetic markers.

Association of Insulin, Metformin, and Statin with Mortality in Breast Cancer Patients

PURPOSE

This study investigated the association of insulin, metformin, and statin use with survival and whether the association was modified by the hormone receptor status of the tumor in patients with breast cancer.

MATERIALS AND METHODS

We studied 7,452 patients who had undergone surgery for breast cancer at Seoul National University Hospital from 2008 to 2015 using the nationwide claims database. Exposure was defined as a recorded prescription of each drug within 12 months before the diagnosis of breast cancer.

RESULTS

Patients with prior insulin or statin use were more likely to be older than 50 years at diagnosis and had a higher comorbidity index than those without it (p < 0.01 for both). The hazard ratio (HR) for death with insulin use was 5.7 (p < 0.01), and the effect was attenuated with both insulin and metformin exposure with an HR of 1.2 (p=0.60). In the subgroup analyses, a heightened risk of death with insulin was further prominent with an HR of 17.9 (p < 0.01) and was offset by co-administration of metformin with an HR of 1.3 (p=0.67) in patients with estrogen receptor (ER)-negative breast cancer. Statin use was associated with increased overall mortality only in patients with ER-positive breast cancer with HR for death of 1.5 (p=0.05).

CONCLUSION

Insulin or statin use before the diagnosis of breast cancer was associated with an increase in all-cause mortality. Subsequent analyses suggested that metformin or statin use may have been protective in patients with ER-negative disease, which warrants further studies.

Palbociclib and beyond for the treatment of HR + HER2- metastatic breast cancer: an Asian-Pacific perspective and practical management guide on the use of CDK4/6 inhibitors

Breast cancer is the most frequent cancer amongst women worldwide including in Asia where the incidence rate is rapidly increasing. Even with treatment, around 30% of patients with early breast cancer progress to metastatic disease, with hormone receptor positive (HR+) and human epidermal growth factor receptor 2 negative (HER2-) breast cancer the most common phenotype. First-line endocrine therapy targeting the estrogen receptor signaling pathway provides a median progression-free survival or time to progression of 6-15 months in HR + HER2- metastatic breast cancer. Recently, cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitors, combined with endocrine therapy, have achieved more than two years median progression-free survival in HR + HER2- metastatic breast cancer. However, the characteristics of the Asian breast cancer population differ from those of Western populations and need to be considered when selecting a suitable treatment. Breast cancer is diagnosed at a younger age in Asian populations and late stage at presentation is generally more common in low-/middle-income countries than high-income countries. Consequently, the proportion of premenopausal women with metastatic breast cancer is higher in Asian compared with Western populations. While CDK4/6 inhibitors have been approved in the USA (FDA) since 2015, experience with them in Asia is more limited. We review the experience with the CDK4/6 inhibitor palbociclib in Asian patients with HR + HER2- metastatic breast cancer and provide guidance on the use of palbociclib in these patients.

European polygenic risk score for prediction of breast cancer shows similar performance in Asian women

Polygenic risk scores (PRS) have been shown to predict breast cancer risk in European women, but their utility in Asian women is unclear. Here we evaluate the best performing PRSs for European-ancestry women using data from 17,262 breast cancer cases and 17,695 controls of Asian ancestry from 13 case-control studies, and 10,255 Chinese women from a prospective cohort (413 incident breast cancers). Compared to women in the middle quintile of the risk distribution, women in the highest 1% of PRS distribution have a ~2.7-fold risk and women in the lowest 1% of PRS distribution has ~0.4-fold risk of developing breast cancer. There is no evidence of heterogeneity in PRS performance in Chinese, Malay and Indian women. A PRS developed for European-ancestry women is also predictive of breast cancer risk in Asian women and can help in developing risk-stratified screening programmes in Asia.

Cost-effectiveness analyses of breast cancer medications use in developing countries: a systematic review

BACKGROUND

Pharmacoeconomic evaluation is important for breast-cancer medications due to their high costs. To our knowledge, no systematic literature reviews of pharmacoeconomic studies for breast-cancer medication use are present in developing-countries.

OBJECTIVES

To systematically review the existing cost-effectiveness evaluations of breast-cancer medication in developing-countries.

METHODOLOGY

A systematic literature search was performed in PubMed, EMBASE, SCOPUS, and EconLit. Two researchers determined the final articles, extracted data, and evaluated their quality using the Quality of Health-Economic Studies (QHES) tool. The interclass-correlation-coefficient (ICC) was calculated to assess interrater-reliability. Data were summarized descriptively.

RESULTS

Fourteen pharmacoeconomic studies published from 2009 to 2019 were included. Thirteen used patient-life-years as their effectiveness unit, of which 10 used quality-adjusted life-years. Most of the evaluations focused on trastuzumab as a single agent or on regimens containing trastuzumab (n = 10). The conclusion of cost-effectiveness analysis varied among the studies. All the studies were of high quality (QHES score >75). Interrater reliability between the two reviewers was high (ICC = 0.76).

CONCLUSION

In many studies included in the review, the use of breast-cancer drugs in developing countries was not cost-effective. Yet, more pharmacoeconomic evaluations for the use of recently approved agents in different disease stages are needed in developing countries.

Effectiveness of Mass and Small Media Campaigns to Improve Cancer Awareness and Screening Rates in Asia: A Systematic Review

PURPOSE

The main objective of this systematic review was to identify whether mass and small media interventions improve knowledge and attitudes about cancer, cancer screening rates, and early detection of cancer in Asia.

METHODS

The review was conducted according to a predefined protocol. Medline, EMBASE, CINAHL, Web of Science, Cochrane Library, and Google Scholar were searched in September 2017, and data extraction and rating of methodologic study quality (according to Joanna Briggs Institute rating procedures) were performed independently by reviewers.

RESULTS

Twenty-two studies (reported across 24 papers) met the inclusion criteria. Most studies (n = 21) were conducted in high or upper-middle income countries; targeted breast (n = 11), cervical (n = 7), colorectal (n = 3), or oral (n = 2) cancer; and used small media either alone (n = 15) or in combination with mass media and other components (n = 5). Studies regarding cancer screening uptake were of medium to high quality and mainly reported positive outcomes for cervical cancer and mixed results for breast and colorectal cancer. The methodologic strength of research that investigated change in cancer-related knowledge and the cost effectiveness of interventions, respectively, were weak and inconclusive.

CONCLUSION

Evidence indicated that small media campaigns seemed to be effective in terms of increasing screening uptake in Asia, in particular cervical cancer screening. Because of the limited number of studies in Asia, it was not possible to be certain about the effectiveness of mass media in improving screening uptake and the effectiveness of campaigns in improving cancer-related knowledge.

Overview of Breast Cancer and Implications of Overtreatment of Early-Stage Breast Cancer: An Indian Perspective

The prevalence and mortality of breast cancer is increasing in Asian countries, including India. With advances in medical technology leading to better detection and characterization of the disease, it has been possible to classify breast cancer into various subtypes using markers, which helps predict the risk of distant recurrence, response to therapy, and prognosis using a combination of molecular and clinical parameters. Breast cancer and its therapy, mainly surgery, systemic therapy (anticancer chemotherapy, hormonal therapy, targeted therapy, and immunotherapy), and radiation therapy, are associated with significant adverse influences on physical and mental health, quality of life, and the economic status of the patient and her family. The fear of recurrence and its devastating effects often leads to overtreatment, with a toxic cost to the patient financially and physically in cases in which this is not required. This article discusses some aspects of a breast cancer diagnosis and its impact on the various facets of the life of the patient and her family. It further elucidates the role of prognostic factors, the currently available biomarkers and prognostic signatures, and the importance of ethnically validating biomarkers and prognostic signatures.

Olaparib monotherapy for Asian patients with a germline BRCA mutation and HER2-negative metastatic breast cancer: OlympiAD randomized trial subgroup analysis

The OlympiAD Phase III study (NCT02000622) established the clinical benefits of olaparib tablet monotherapy (300 mg twice daily) over chemotherapy treatment of physician’s choice (TPC) in patients with a germline BRCA1/2 mutation (gBRCAm) and human epidermal growth factor receptor 2 (HER2)-negative metastatic breast cancer who had received ≤2 chemotherapy lines in the metastatic setting. Here, we report pre-specified analyses of data from Asian (China, Japan, Korea and Taiwan) patients in the study. All patients were randomized 2:1 to olaparib tablets (300 mg twice daily) or single-agent chemotherapy TPC (21-day cycles of either capecitabine, eribulin or vinorelbine). The primary endpoint was progression-free survival assessed by blinded independent central review. The prevalence of gBRCAm in the OlympiAD Asian subgroup screened for study recruitment was 13.5%. Patient demographics and disease characteristics of the Asian subgroup (87/302 patients) were generally well balanced between treatment arms. Asian patients in the olaparib arm achieved longer median progression-free survival, assessed by blinded independent central review, versus the chemotherapy TPC arm (5.7 vs 4.2 months; HR = 0.53 [95% CI: 0.29–0.97]), which was consistent with findings in the global OlympiAD study population. Findings on secondary efficacy and safety/tolerability outcome measures in Asian patients were also similar to those observed in the global OlympiAD study population. The OlympiAD study was not powered to detect race-related differences between treatment groups; however, the consistency of our findings with the global OlympiAD study population suggests that previously reported findings are generalizable to Asian patients.

Economic Evaluation of Breast Cancer Early Detection Strategies in Asia: A Systematic Review

OBJECTIVE

This article aims to support the development of practical guidelines for early detection of breast cancer in Asia by systematically reviewing economic evaluation studies of such early detection strategies in Asian countries.

METHODS

A systematic literature review was conducted following the Cochrane Handbook and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis Protocols checklist. The quality of reviewed studies was examined using the Consolidated Health Economic Evaluation Reporting Standards statement.

RESULTS

A total of 15 articles on the economic evaluation of breast cancer early detection based in Asia were reviewed. Cost-effectiveness was used in all the studies as the analytic method to compare the cost and consequences of different screening policies. Ten studies were categorized as incorporating the modeled approach. Fourteen studies analysed the cost-effectiveness of the organized population-based approach, in which mammography screening was the prevailing screening modality. Only one study evaluated the cost-effectiveness of early diagnosis for breast cancer patients in order to provide early treatment. The results from the identified economic evaluations, and consequent recommendations concerning optimal early detection strategies varied among studies, and depended on key parameters and assumption used, as well as differences in inter-country health resources, breast cancer incidence, prevalence and early detection pathways.

CONCLUSIONS

The economic evaluation of breast cancer early detection programs is still limited in Asia. Policy decisions on organized mammography screening in women <50 are economically attractive in the region, despite the lack of evidence to provide recommendations on opportunistic screening strategy and early diagnosis strategy. Future studies need to provide better transparency of the data used and cover more comprehensive strategies, to make them relevant and adaptable to other Asian countries, resulting in clear policy recommendations on breast cancer early detection strategies.

Quantitative stain-free imaging and digital profiling of collagen structure reveal diverse survival of triple negative breast cancer patients

Background

Stromal and collagen biology has a significant impact on tumorigenesis and metastasis. Collagen is a major structural extracellular matrix component in breast cancer, but its role in cancer progression is the subject of historical debate. Collagen may represent a protective layer that prevents cancer cell migration, while increased stromal collagen has been demonstrated to facilitate breast cancer metastasis.

Methods

Stromal remodeling is characterized by collagen fiber restructuring and realignment in stromal and tumoral areas. The patients in our study were diagnosed with triple-negative breast cancer in Singapore General Hospital from 2003 to 2015. We designed novel image processing and quantification pipelines to profile collagen structures using numerical imaging parameters. Our solution differentiated the collagen into two distinct modes: aggregated thick collagen (ATC) and dispersed thin collagen (DTC).

Results

Extracted parameters were significantly associated with bigger tumor size and DCIS association. Of numerical parameters, ATC collagen fiber density (CFD) and DTC collagen fiber length (CFL) were of significant prognostic value for disease-free survival and overall survival for the TNBC patient cohort. Using these two parameters, we built a predictive model to stratify the patients into four groups.

Conclusions

Our study provides a novel insight for the quantitation of collagen in the tumor microenvironment and will help predict clinical outcomes for TNBC patients. The identified collagen parameters, ATC CFD and DTC CFL, represent a new direction for clinical prognosis and precision medicine. We also compared our result with benign samples and DICS samples to get novel insight about the TNBC heterogeneity. The improved understanding of collagen compartment of TNBC may provide insights into novel targets for better patient stratification and treatment.

Chemoprevention of Breast Cancer With Vitamins and Micronutrients: A Concise Review

Numerous dietary components and vitamins have been found to inhibit the molecular events and signalling pathways associated with various stages of breast cancer development. To identify the vitamins and dietary micronutrients that exert protective effects against breast cancer and define their mechanism of action, we performed a literature review of in vitro, animal and epidemiological studies and selected the in vitro and animal studies with robust molecular evidence and the epidemiological studies reporting statistically significant inverse associations for a breast cancer-specific protective effect. There is sufficient evidence from in vitro, animal and epidemiological human studies that certain vitamins, such as vitamin D3, folate, vitamin B6, and beta carotene as well as dietary micronutrients, such as curcumin, piperine, sulforaphane, indole-3-carbinol, quercetin, epigallocatechin gallate (EGCG) and omega-3 polyunsaturated fatty acids (PUFAs), display an antitumoral activity against breast cancer and have the potential to offer a natural strategy for breast cancer chemoprevention and reduce the risk of breast cancer recurrence. Therefore, a supplement that contains these micronutrients, using the safest form and dosage should be investigated in future breast cancer chemoprevention studies and as part of standard breast cancer therapy.

Association of Overweight and Obesity with Breast Cancer During Premenopausal Period in Asia: A Meta-Analysis

Background:

The association of overweight and obesity with breast cancer risk in premenopausal women and in different ethnicities remains in debate, especially among Asian women. The aim of this systematic review and meta-analysis was to determine the association of overweight and obesity with breast cancer during premenopausal period in Asian women.

Methods:

We performed a meta-analysis of research articles on the association of overweight and obesity with breast cancer during premenopausal period in Asian women published from January 2000 to July 2018 in article databases of EBSCO, PubMed, and ProQuest. Pooled odds ratios (ORs) were calculated by fixed and random-effect models. Publication bias was visually evaluated using funnel plots, and then statistically assessed using Egger's and Begg's tests. Review Manager 5.3 (RevMan 5.3) and Stata version 14.2 (Stata Corporation) were used to process the data. We reviewed 886 articles.

Results:

We found 15 studies conducted systematic review continued by meta-analysis of relevant data with 22,362 patients. There was significant association of obesity [OR = 1.36 (95% confidence interval (CI) 1.26–1.47, P < 0.00001)] and overweight [OR = 1.17 (95% CI 1.10–1.25, P < 0.00001)] with breast cancer during premenopausal period in Asian women. In this study, there was no significant publication bias for studies included in overweight and obesity with breast cancer during premenopausal in Asian women.

Conclusions:

This study suggested association of overweight and obesity with breast cancer during premenopausal period in Asian women.

Clinical and epidemiologic factors associated with breast cancer and its subtypes among Northeast Chinese women

The incidence of breast cancer has increased dramatically in China. We evaluated the clinical and epidemiologic factors associated with breast cancer, and its stage in a case‐control study of Northeast Chinese women. We also examined whether these factors were differentially distributed among molecular subtypes of breast cancer in a case‐only analysis. We identified 1118 breast cancer patients and 2284 healthy women from Cancer Hospital of Medical University between January 2014 and December 2017. Logistic regression models were used to calculate the odds ratios (ORs) and corresponding 95% confidence intervals (CIs). We found that postmenopausal women had a decreased risk of breast cancer (multivariate‐adjusted OR = 0.33, 95% CI:0.25‐0.43), and tended to have breast cancer of human epidermal growth factor receptor 2 (HER2)‐overexpressing (multivariate‐adjusted OR = 2.99, 95% CI: 1.49‐5.97) and triple‐negative (multivariate‐adjusted OR = 2.16, 95% CI: 1.02‐4.56) subtypes, compared with the luminal B subtype. Women with history of abortion had an increased risk of breast cancer (multivariate‐adjusted OR = 4.70, 95% CI: 3.60‐6.14). Women with high breast density and high Breast Imaging Reporting and Data System (BIRADS) scores of lesions tended to have breast cancer of advanced stage, but were not differentially distributed among its molecular subtypes. In conclusion, postmenopausal women had decreased risk of breast cancer, and tended to have nonluminal subtype, while women with history of abortion had increased risk of breast cancer. Women with high breast density and BIRADS scores of lesions tended to have advanced stage breast cancer. We provide evidence on the epidemiologic factors for breast cancer and its subtypes, which may help with breast cancer risk stratification.

Neratinib-based therapy in patients with metastatic HER2-positive breast cancer from Asia

Aim: To evaluate the safety and efficacy of neratinib-based therapy in Asian patients with HER2-positive metastatic breast cancer (MBC). Patients & methods: We performed a pooled analysis of seven early-phase studies of neratinib given either as monotherapy or in combination with chemotherapeutic agents or trastuzumab in patients with advanced solid tumors. Results: A total of 793 patients with HER2-positive MBC were included in the efficacy analysis (Asia: 271 patients; other regions: 522 patients). The overall response rate in patients from Asia was 66.4% (180/271) and the median progression-free survival was 55.6 weeks. The most common adverse event in patients from Asia was diarrhea (all-grade: 96.3%; grade 3: 27.4%). Conclusion: Neratinib-based therapy is safe and effective in patients with HER2-positive MBC from Asia.

Prognostic Impact of Pregnancy in Korean Patients with Breast Cancer

BACKGROUND

Pregnancy concurrent with, shortly before, or after breast cancer poses unique challenges because hormonal changes in pregnancy potentially interact with breast cancer outcomes.

MATERIALS AND METHODS

We studied a cohort of 3,687 female patients of reproductive age (<50 years) with breast cancer, linking a large institutional database and the nationwide claims database to comprehensively capture exposure status and tumor characteristics. Exposures included breast cancer during pregnancy, postpartum breast cancer (<12 months after delivery), and pregnancy after breast cancer.

RESULTS

Forty-five patients with postpartum breast cancer were significantly more likely to have advanced stage, hormone receptor-negative tumor and to be younger than 35 years at diagnosis than those without postpartum breast cancer. This trend was not observed with 18 patients with breast cancer during pregnancy. The unadjusted 5-year survival rates were 77% versus 96% for patients with postpartum breast cancer versus their counterparts, 89% versus 96% for patients with breast cancer during pregnancy versus their counterparts, and 98% versus 96% for patients with pregnancy after breast cancer versus their counterparts, respectively. In the multivariable analyses, postpartum breast cancer exhibited hazard ratios for death of 1.57 (95% confidence interval [CI], 0.82-2.99), whereas those for breast cancer during pregnancy and pregnancy after breast cancer were 1.09 (95% CI, 0.15-7.91) and 0.86 (95% CI, 0.26-2.83), respectively.

CONCLUSION

Postpartum breast cancer, but not breast cancer during pregnancy, was associated with advanced stage, younger age at diagnosis (<35 years), hormone receptor-negative disease, and poorer survival. Pregnancy after breast cancer did not compromise overall survival.

IMPLICATIONS FOR PRACTICE

Although pregnancy around the time of diagnosis of breast cancer is expected to become increasingly common with maternal age at first childbirth on the rise, data on the prognostic impact of pregnancy have been inconsistent and rare from Asian populations. In this investigation of a Korean patient cohort with breast cancer, pregnancy-associated breast cancer was associated with advanced stage, younger age at diagnosis (<35 years), hormone receptor-negative disease, and poorer survival. This adverse impact of pregnancy on the prognosis was apparent with postpartum breast cancer but not observed with breast cancer during pregnancy. Pregnancy after breast cancer did not compromise overall survival.

Neratinib after trastuzumab-based adjuvant therapy in patients from Asia with early stage HER2-positive breast cancer

Aim: To evaluate the efficacy and safety of neratinib as extended adjuvant therapy in patients from Asia based on exploratory analyses of the Phase III ExteNET trial. Patients & methods: A total of 2840 women with early stage HER2-positive breast cancer were randomly assigned to neratinib 240 mg/day or placebo for 1 year after trastuzumab-based adjuvant therapy. Results: A total of 341 patients were from Asia (neratinib, n = 165; placebo, n = 176). 2-year invasive disease-free survival rates were 92.8 and 90.8% with neratinib and placebo, respectively (HR: 0.70; 95% CI: 0.31-1.55), and 5-year rates were 91.9 and 87.2%, respectively (HR: 0.57; 95% CI: 0.27-1.13). Diarrhea was the most common adverse event with neratinib. Conclusion: Extended adjuvant therapy with neratinib reduces disease recurrences in Asian women with HER2-positive breast cancer. Trial registration: Clinicaltrials.gov NCT00878709.

Retrospectively validating the results of the ACOSOG Z0011 trial in a large Asian Z0011-eligible cohort

PURPOSE

The Z0011 trial demonstrated that axillary dissection (ALND) could be omitted during breast-conserving therapy for cT1-2N0 breast cancers with 1-2 metastatic SLNs. However, that result has not been validated in a larger cohort and the significance of the small number of SLNs remains unclear. This study aimed to validate the Z0011 results within an Asian Z0011-eligible cohort and determine whether the number of sentinel lymph nodes (SLNs) influenced the Z0011-based outcomes.

METHODS

Data from Asian patients who fulfilled the Z0011 criteria were collected from five hospitals. Disease recurrence (DR) was compared between patients who underwent ALND or SLN dissection (SLND) alone. Propensity-score matching was performed to reduce the effects of potential selection biases.

RESULTS

During 2010-2016, 1750 Asian patients had 1-2 SLN metastases and fulfilled the Z0011 criteria. These patients included 707 cases treated using SLND alone (40%) and 967 patients with ≤ 2 SLNs (55%). Ninety-five patients (5.4%) experienced DR at a median interval of 50 months, although the rates of DR were similar in the ALND and SLND groups. The adjusted hazard ratios for DR after ALND omission were 0.95 (95% CI 0.55-1.64) among the entire cohort and 0.83 (95% CI 0.34-2.03) among patients with ≤ 2 SLNs.

CONCLUSIONS

In this Asian Z0011-eligible cohort, ALND omission did not increase risk of DR, even among patients with ≤ 2 SLNs. Therefore, the Z0011 strategy might be safely applied in Asia, and a small number of SLNs did not significantly influence this strategy.

Harnessing genomics to improve outcomes for women with cancer in India: key priorities for research

Cumulatively, breast, cervical, ovarian, and uterine cancer account for more than 70% of cancers in women in India. Distinct differences in the clinical presentation of women with cancer suggest underlying differences in cancer biology and genetics. The peak age of onset of breast and ovarian cancer appears to be a decade earlier in India (age 45-50 years) than in high-income countries (age >60 years). Understanding these differences through research to develop diagnosis, screening, prevention, and treatment frameworks that ar e specific to the Indian population are critical and essential to improving women's health in India. Since the sequencing of the human genome in 2001, applications of advanced technologies, such as massively parallel sequencing, have transformed the understanding of the genetic and environmental drivers of cancer. How can advanced technologies be harnessed to provide health-care solutions at a scale and to a budget suitable for a country of 1·2 billion people? What research programmes are necessary to answer questions specific to India, and to build capacity for innovative solutions using these technologies? In order to answer these questions, we convened a workshop with key stakeholders to address these issues. In this Series paper, we highlight challenges in tackling the growing cancer burden in India, discuss ongoing genomics research and developments in infrastructure, and suggest key priorities for future research in cancer in India.

Socio-Economic Status Inequity in Self Rated Health in Patients with Breast Cancer

AIM:

We investigate the evaluation of socio-economic status (SES) inequality on self-rated health (SRH) at women with breast cancer.

STUDY DESIGN:

Cross-sectional study

METHODS:

The current study conducted on all 270 breast cancer patients that were admitted to one of the hospitals of Arak University Medical Sciences (Arak, Iran from April to July 2018) by census (using non-random sampling (accessible sampling). SES was calculated by asset-based questionnaire and Principle Component Analysis (PCA) was performed to estimate the families’ SES. Concentration Index (C) and Curve (CC) was used to measure SES inequality in SRH. The data were analysed with Stata software.

RESULTS:

The number of persons with good SRH by the level of SES was 165 (61.1%) and with poor SRH was 105 (38.9%). The number of persons with good SRH in comparison to same-aged people by level of SES was 135 (50%) and with poor SRH was 135 (50%). Concentration index of SRH in all level of SES was 0.061 (SE = 0.03). Also, Concentration index for SRH in comparison to same-aged people at different levels of SES was -0.044 (SE = 0.03).

CONCLUSION:

The results of this study showed that there is inequality in SRH in a patient with breast cancer of the richest level of SES.

Observer Variability in Breast Cancer Diagnosis between Countries with and without Breast Screening

RATIONAL AND OBJECTIVES

Image reporting is a vital component of patient management depending on individual radiologists' performance. Our objective was to explore mammographic diagnostic efficacy in a country where breast cancer screening does not exist.

MATERIALS AND METHODS

Two mammographic test sets were used: a typical screening (TS) and high-difficulty (HD) test set. Nonscreening (NS) radiologists (n = 11) read both test sets, while 52 and 49 screening radiologists read the TS and HD test sets, respectively. The screening radiologists were classified into two groups: a less experienced (LE) group with ≤5 years' experience and a more experienced (ME) group with ≥5 years' experience. A Kruskal-Wallis and Tukey-Kramer post hoc test were used to compare reading performance among reader groups, and the Wilcoxon matched pairs tests was used to compare TS and ND test sets for the NS radiologists.

RESULTS

Across the three reader groups, there were significant differences in case sensitivity (χ² [2] = 9.4, P = .008), specificity (χ² [2] = 10.3, P = .006), location sensitivity (χ² [2] = 19.8, P < .001), receiver operating characteristics, area under the curve (χ² [2] = 19.7, P < .001) and jack-knife free-response receiver operating characteristics (JAFROCs) (χ² [2] = 18.1, P < .001). NS performance for all measured scores was significantly lower than those for the ME readers (P < .006), while only location sensitivity was lower (χ² [2] = 17.5, P = .026) for the NS compared to the LE group. No other significant differences were observed.

CONCLUSION

Large variations in mammographic performance exist between radiologists from screening and nonscreening countries.

Serum Trace Elements and Their Associations with Breast Cancer Subgroups in Korean Breast Cancer Patients

The relationships between serum levels of trace elements and breast cancer remain relatively unknown. In this study, we investigate serum levels of seven trace elements in Korean breast cancer patients compared to controls without breast cancer. Serum trace element levels were determined using inductively coupled plasma mass spectrometry in Korean breast cancer patients before initiation of breast cancer treatment. Korean females without breast cancer served as a control group. Trace element levels were measured in the discovery cohort (n = 287) and were validated in an independent cohort (n = 142). We further investigated possible associations between trace element levels and the presence of lymph node metastasis, distant metastasis, or triple-negative breast cancer among breast cancer patients in subgroup analyses. Serum manganese and molybdenum levels were significantly higher (p < 0.05) in breast cancer patients than in controls. Serum copper levels were significantly higher in breast cancer patients with distant metastasis, while selenium levels were significantly lower. Other trace elements were neither significantly different between breast cancer patients and controls nor between subgroups of breast cancer patients. Our study provides insights about the potential roles and impacts of trace elements through an assessment of the associations between trace elements and breast cancer.

No association of TP53 codon 72 and intron 3 16-bp duplication polymorphisms with breast cancer risk in Chinese Han women: new evidence from a population-based case-control investigation

Background

Many studies have demonstrated that the genetic variants of tumor suppressor gene TP53 contribute to the prediction of breast cancer risk. However, most of them focused on Europeans and Americans; the investigations about Asians, especially Chinese women, are scarce. Thus, the aim of this study was to explore the influence of TP53 codon 72 and intron 3 16-bp duplication polymorphisms on the breast cancer risk in Chinese women, especially those from eastern China.

Methods

Blood samples collected from 254 breast cancer patients and 252 healthy female individuals were investigated. Genotypes of the two polymorphisms were determined by direct sequencing and conventional PCR, respectively.

Results

Heterozygous Arg/Pro and homozygous Del/Del were the most frequent genotypes of the two polymorphisms, respectively. Heterozygous Arg/Pro had a higher prevalence in breast cancer cases (P_adj = 0.10; OR_adj = 1.43, 95% CI 0.93–2.18), and no homozygous 16-bp duplication (Ins/Ins) genotype was found in the whole 506 clinical samples. For the distributions of allele and haplotype frequencies, no statistically significant difference was observed between the two groups when multiple (additive, dominant and recessive) genetic models were utilized in the analysis (P_adj > 0.05).

Conclusion

The results suggested that the two TP53 polymorphisms did not affect breast cancer risk in Chinese Han women, but the heterozygous Arg/Pro may exist as the possible risk genotype of the codon 72 polymorphism in contrast to the homozygous Arg/Arg and Pro/Pro.

Electronic supplementary material

The online version of this article (10.1186/s40001-018-0345-6) contains supplementary material, which is available to authorized users.

BRCA1 Promoter Methylation and Clinicopathological Characteristics in Sporadic Breast Cancer Patients in Indonesia

Objective:

The aim of this study was to investigate the BRCA1 promoter methylation and clinicopathological characteristics in sporadic breast cancer patients in Indonesia.

Methods:

In this cohort study, we selected 90 patients with stage I-III who had definitive surgery at our institution in 2011-2014. Demographic and clinical data regarding pathological stage, breast cancer treatment, outcome etc. were collected from the medical records. Twelve patients had incomplete information on follow up and 18 samples had insufficient tissues for the experiment. Sixty patients with adequate cancer tissues and complete follow up record were analyzed, only 56 patients were analyzed because 4 samples mRNA expression could not be detected. The Mann–Whitney U tests for non-normally distributed groups were used to compare the levels expression of BRCA1 mRNA between methylated and non-methylated samples. Chi-square tests were used to compare methylation status, BRCA1 mRNA expression and clinicopathological characteristics. P value < 0.05 was considered as statistically significant correlation. Data analysis was held by using the GraphPad PRISM 7 (GraphPad Software Inc., USA).

Results:

DNA and RNA were isolated from primary tumor tissues of 56 breast cancer patients. BRCA1 promoter methylation was detected in 48 of 56 patients (85%). Level of BRCA1 mRNA expression was associated with decreased methylation level in the BRCA1 promoter regions suggesting the role of epigenetic silencing. However, there was no statistically significant association among methylation levels, BRCA1 mRNA transcript level with clinicopathological factors.

Conclusion:

To our knowledge, this is the first study investigating methylation status and level of BRCA1 mRNA transcripts among breast cancer patients in Indonesia. We found that the prevalence of BRCA1 promoter methylation is higher than other studies from different populations. However, further investigation involving larger number of patients is required.

Mammographic detection of breast cancer in a non-screening country

OBJECTIVE:

To compare the diagnostic accuracy between radiologists' from a country with and without breast cancer screening.

METHODS:

All participating radiologists gave informed consent. A test-set involving 60 mammographic cases (20 cancer and 40 non-cancer) were read by 11 radiologists from a non-screening (NS) country during a workshop in July 2016. 52 radiologists from a screening country read the same test-set at the Royal Australian and New Zealand College of Radiologists' meetings in July 2015. The screening radiologists were classified into two groups: those with less than or equal to 5 years of experience; those with more than 5 years of experience, and each group was compared to the group of NS radiologists. A Kruskal-Wallis test followed by post-hoc multiple comparisons test were used to compare measures of diagnostic accuracy among the reader groups.

RESULTS:

The diagnostic accuracy of the NS radiologists was significantly lower in terms of sensitivity [mean = 54.0; 95% confidence interval (CI) (40.0-67.0)], location sensitivity [mean = 26.0; 95% CI (16.0-37.0)], receive roperating characteristic area under curve [mean = 73.0; 95% CI (66.5-81.0)] and Jackknifefree-response receiver operating characteristics figure-of-merit [mean = 45.0; 95% CI (40.0-50.0)] when compared with the less and more experienced screening radiologists, whilst no difference in specificity [mean = 75.0; 95% CI (70.0- 81.0)] was found. No significant differences in all measured diagnostic accuracy were found between the two groups of screening radiologists.

CONCLUSION:

The mammographic performance of a group of radiologists from a country without screening program was suboptimal compared with radiologists from Australia.

ADVANCES IN KNOWLEDGE:

Identifying mammographic performance in developing countries is required to optimize breast cancer diagnosis.