METHODS: In this study, we built a new model (Asian Risk Calculator) for estimating the likelihood of carrying a pathogenic variant in BRCA1 or BRCA2 gene, using germline BRCA genetic testing results in a cross-sectional population-based study of 8,162 Asian patients with breast cancer. We compared the model performance to existing mutation prediction models. The models were evaluated for discrimination and calibration.
RESULTS: Asian Risk Calculator included age of diagnosis, ethnicity, bilateral breast cancer, tumor biomarkers, and family history of breast cancer or ovarian cancer as predictors. The inclusion of tumor grade improved significantly the model performance. The full model was calibrated (Hosmer-Lemeshow P value = .614) and discriminated well between BRCA and non-BRCA pathogenic variant carriers (area under receiver operating curve, 0.80; 95% CI, 0.75 to 0.84). Addition of grade to the existing clinical genetic testing criteria targeting patients with breast cancer age younger than 45 years reduced the proportion of patients referred for genetic counseling and testing from 37% to 33% (P value = .003), thereby improving the overall efficacy.
CONCLUSION: Population-specific customization of mutation prediction models and clinical genetic testing criteria improved the accuracy of BRCA mutation prediction in Asian patients.
METHOD: A historical cohort of 986 premenopausal, and 1123 postmenopausal, parous breast cancer patients diagnosed from 2001 to 2012 in University Malaya Medical Centre were included in the analyses. Time since LCB was categorized into quintiles. Multivariable Cox regression was used to determine whether time since LCB was associated with survival following breast cancer, adjusting for demographic, tumor, and treatment characteristics.
RESULTS: Premenopausal breast cancer patients with the most recent childbirth (LCB quintile 1) were younger, more likely to present with unfavorable prognostic profiles and had the lowest 5-year overall survival (OS) (66.9; 95% CI 60.2-73.6%), compared to women with longer duration since LCB (quintile 2 thru 5). In univariable analysis, time since LCB was inversely associated with risk of mortality and the hazard ratio for LCB quintile 2, 3, 4, and 5 versus quintile 1 were 0.53 (95% CI 0.36-0.77), 0.49 (95% CI 0.33-0.75), 0.61 (95% CI 0.43-0.85), and 0.64 (95% CI 0.44-0.93), respectively; P trend = 0.016. However, this association was attenuated substantially following adjustment for age at diagnosis and other prognostic factors. Similarly, postmenopausal breast cancer patients with the most recent childbirth were also more likely to present with unfavorable disease profiles. Compared to postmenopausal breast cancer patients in LCB quintile 1, patients in quintile 5 had a higher risk of mortality. This association was not significant following multivariable adjustment.
CONCLUSION: Time since LCB is not independently associated with survival in premenopausal or postmenopausal breast cancers. The apparent increase in risks of mortality in premenopausal breast cancer patients with a recent childbirth, and postmenopausal patients with longer duration since LCB, appear to be largely explained by their age at diagnosis.
OBJECTIVE: To assess the global distribution of breast cancer stage by country, age group, calendar period, and socioeconomic status using population-based data.
DATA SOURCES: A systematic search of MEDLINE and Web of Science databases and registry websites and gray literature was conducted for articles or reports published between January 1, 2000, and June 20, 2022.
STUDY SELECTION: Reports on stage at diagnosis for individuals with primary breast cancer (C50) from a population-based cancer registry were included.
DATA EXTRACTION AND SYNTHESIS: Study characteristics and results of eligible studies were independently extracted by 2 pairs of reviewers (J.D.B.F., A.D.A., A.M., R.S., and F.G.). Stage-specific proportions were extracted and cancer registry data quality and risk of bias were assessed. National pooled estimates were calculated for subnational or annual data sets using a hierarchical rule of the most relevant and high-quality data to avoid duplicates.
MAIN OUTCOMES AND MEASURES: The proportion of women with breast cancer by (TNM Classification of Malignant Tumors or the Surveillance, Epidemiology, and End Results Program [SEER]) stage group.
RESULTS: Data were available for 2.4 million women with breast cancer from 81 countries. Globally, the proportion of cases with distant metastatic breast cancer at diagnosis was high in sub-Saharan Africa, ranging from 5.6% to 30.6% and low in North America ranging from 0.0% to 6.0%. The proportion of patients diagnosed with distant metastatic disease decreased over the past 2 decades from around 3.8% to 35.8% (early 2000s) to 3.2% to 11.6% (2015 onwards), yet stabilization or slight increases were also observed. Older age and lower socioeconomic status had the largest proportion of cases diagnosed with distant metastatic stage ranging from 2.0% to 15.7% among the younger to 4.1% to 33.9% among the oldest age group, and from 1.7% to 8.3% in the least disadvantaged groups to 2.8% to 11.4% in the most disadvantaged groups.
CONCLUSIONS AND RELEVANCE: Effective policy and interventions have resulted in decreased proportions of women diagnosed with metastatic breast cancer at diagnosis in high-income countries, yet inequality persists, which needs to be addressed through increased awareness of breast cancer symptoms and early detection. Improving global coverage and quality of population-based cancer registries, including the collection of standardized stage data, is key to monitoring progress.
METHODS: All 5616 patients, diagnosed with breast cancer in University Malaya Medical Centre from 1999 to 2013 were included. In 945 elderly patients (aged 65 years and above), multivariable logistic regression was performed to identify factors associated with treatment, following adjustment for age, ethnicity, tumor, and other treatment characteristics. The impact of lack of treatment on survival of the elderly was assessed while accounting for comorbidities.
RESULTS: One in five elderly patients had comorbidities. Compared to younger patients, the elderly had more favorable tumor characteristics, and received less loco-regional treatment and chemotherapy. Within stage I-IIIa elderly breast cancer patients, 10 % did not receive any surgery. These patients were older, more likely to be Malays, have comorbidities, and bigger tumors. In elderlies with indications for adjuvant radiotherapy, no irradiation (30 %) was associated with increasing age, comorbidity, and the absence of systemic therapy. Hormone therapy was optimal, but only 35 % of elderly women with ER negative tumors received chemotherapy. Compared to elderly women who received adequate treatment, those not receiving surgery (adjusted hazard ratio: 2.30, 95 %CI: 1.10-4.79), or radiotherapy (adjusted hazard ratio: 1.56, 95 %CI: 1.10-2.19), were associated with higher mortality. Less than 25 % of the survival discrepancy between elderly women receiving loco-regional treatment and no treatment were attributed to excess comorbidities in untreated patients.
CONCLUSION: While the presence of comorbidities significantly influenced loco-regional treatment decisions in the elderly, it was only able to explain the lower survival rates in untreated patients up to a certain extent, suggesting missed opportunities for treatment.
METHODS: Through the Association of Southeast Asian Nations Costs in Oncology study, 1,294 newly diagnosed patients with cancer (Ministry of Health [MOH] hospitals [n = 577], a public university hospital [n = 642], private hospitals [n = 75]) were observed in Malaysia. Cost diaries and questionnaires were used to measure incidence of financial toxicity, encompassing financial catastrophe (FC; out-of-pocket costs ≥ 30% of annual household income), medical impoverishment (decrease in household income from above the national poverty line to below that line after subtraction of cancer-related costs), and economic hardship (inability to make necessary household payments). Predictors of financial toxicity were determined using multivariable analyses.
RESULTS: One fifth of patients had private health insurance. Incidence of FC at 1 year was 51% (MOH hospitals, 33%; public university hospital, 65%; private hospitals, 72%). Thirty-three percent of households were impoverished at 1 year. Economic hardship was reported by 47% of families. Risk of FC attributed to conventional medical care alone was 18% (MOH hospitals, 5%; public university hospital, 24%; private hospitals, 67%). Inclusion of expenditures on nonmedical goods and services inflated the risk of financial toxicity in public hospitals. Low-income status, type of hospital, and lack of health insurance were strong predictors of FC.
CONCLUSION: Patients with cancer may not be fully protected against financial hardships, even in settings with universal health coverage. Nonmedical costs also contribute as important drivers of financial toxicity in these settings.
METHODS: Country-specific data from a multinational prospective cohort study, Association of Southeast Asian Nations Costs in Oncology Study, comprising 1,249 cancer survivors were included. Household costs of complementary medicine (healthcare practices or products that are not considered as part of conventional medicine) throughout the first year after cancer diagnosis were measured using cost diaries. Study outcomes comprised (1) shares of household expenditures on complementary medicine from total out-of-pocket costs and health costs that were respectively incurred in relation to cancer, (2) incidence of financial catastrophe (out-of-pocket costs related to cancer ≥ 30% of annual household income), and (3) economic hardship (inability to pay for essential household items or services).
RESULTS: One third of patients reported out-of-pocket household expenditures on complementary medicine in the immediate year after cancer diagnosis, accounting to 20% of the total out-of-pocket costs and 35% of the health costs. Risk of financial catastrophe was higher in households reporting out-of-pocket expenditures on complementary medicine (adjusted odds ratio: 1.39 [95% CI, 1.05 to 1.86]). Corresponding odds ratio within patients from low-income households showed that they were substantially more vulnerable: 2.28 (95% CI, 1.41 to 3.68). Expenditures on complementary medicine were, however, not associated with economic hardship in the immediate year after cancer diagnosis.
CONCLUSION: In settings with universal health coverage, integration of subsidized evidence-based complementary medicine into mainstream cancer care may alleviate catastrophic expenditures. However, this must go hand in hand with interventions to reduce the use of nonevidence-based complementary therapies following cancer.
METHODS: All 4930 women diagnosed with breast cancer in University Malaya Medical Center, Malaysia from 1993 to 2011 were included. Factors associated with very early presentation (stage I) at diagnosis were identified. Tumour characteristics, management patterns, and survival of very early breast cancer were described, and where appropriate, compared with other settings.
RESULTS: Proportion of women presenting with stage I breast cancer significantly increased from 15.2% to 25.2% over two decades. Factors associated with very early presentation were Chinese ethnicity, positive family history of breast cancer, and recent period of diagnosis. Within stage I breast cancers, median tumour size at presentation was 1.5 cm. A majority of stage I breast cancer patients received mastectomy, which was associated with older age, Chinese ethnicity, postmenopausal status, and larger tumours. Chemotherapy was administered in 36% of patients. Five-year age-adjusted relative survival for women with stage I breast cancer was 99.1% (95% CI: 97.6-99.6%).
CONCLUSIONS: The proportion of women presenting with very early breast cancer in this setting without organised screening is increasing. These women seem to survive just as well as their counterparts from affluent settings.
METHOD: All newly diagnosed breast cancer patients with node-negative and hormone receptor negative tumors measuring≤2cm at the University Malaya Medical Centre (Malaysia) from 1993 to 2013 were included. Mortality of patients with and without adjuvant chemotherapy were compared and adjusted for possible confounders using propensity score.
RESULTS: Of 6732 breast cancer patients, 341 (5.1%) had small (≤2cm), node-negative and hormone receptor negative tumors at diagnosis. Among them, only 214 (62.8%) received adjuvant chemotherapy. Five-year overall survival was 88.1% (95% confidence interval (CI): 82.0%-94.2%) for patients receiving chemotherapy and 89.6% (95% CI: 85.1%-94.1%) for patients without chemotherapy. Chemotherapy was not associated with survival following adjustment for age, ethnicity, tumor size, tumor grade, HER2 status, lympho-vascular invasion, type of surgery and radiotherapy administration. However, chemotherapy was associated with a significant survival advantage (adjusted hazard ratio: 0.35, 95%CI: 0.14-0.91) in a subgroup of women with high-grade tumors.
CONCLUSION: Adjuvant chemotherapy does not appear to be associated with a survival benefit in women with T1N0M0, hormone receptor negative breast cancer except in those with high-grade tumors.
OBJECTIVE: To characterize tumors associated with BC susceptibility genes in large-scale population- or hospital-based studies.
DESIGN, SETTING, AND PARTICIPANTS: The multicenter, international case-control analysis of the BRIDGES study included 42 680 patients and 46 387 control participants, comprising women aged 18 to 79 years who were sampled independently of family history from 38 studies. Studies were conducted between 1991 and 2016. Sequencing and analysis took place between 2016 and 2021.
EXPOSURES: Protein-truncating variants and likely pathogenic missense variants in ATM, BARD1, BRCA1, BRCA2, CHEK2, PALB2, RAD51C, RAD51D, and TP53.
MAIN OUTCOMES AND MEASURES: The intrinsic-like BC subtypes as defined by estrogen receptor, progesterone receptor, and ERBB2 (formerly known as HER2) status, and tumor grade; morphology; size; stage; lymph node involvement; subtype-specific odds ratios (ORs) for carrying protein-truncating variants and pathogenic missense variants in the 9 BC susceptibility genes.
RESULTS: The mean (SD) ages at interview (control participants) and diagnosis (cases) were 55.1 (11.9) and 55.8 (10.6) years, respectively; all participants were of European or East Asian ethnicity. There was substantial heterogeneity in the distribution of intrinsic subtypes by gene. RAD51C, RAD51D, and BARD1 variants were associated mainly with triple-negative disease (OR, 6.19 [95% CI, 3.17-12.12]; OR, 6.19 [95% CI, 2.99-12.79]; and OR, 10.05 [95% CI, 5.27-19.19], respectively). CHEK2 variants were associated with all subtypes (with ORs ranging from 2.21-3.17) except for triple-negative disease. For ATM variants, the association was strongest for the hormone receptor (HR)+ERBB2- high-grade subtype (OR, 4.99; 95% CI, 3.68-6.76). BRCA1 was associated with increased risk of all subtypes, but the ORs varied widely, being highest for triple-negative disease (OR, 55.32; 95% CI, 40.51-75.55). BRCA2 and PALB2 variants were also associated with triple-negative disease. TP53 variants were most strongly associated with HR+ERBB2+ and HR-ERBB2+ subtypes. Tumors occurring in pathogenic variant carriers were of higher grade. For most genes and subtypes, a decline in ORs was observed with increasing age. Together, the 9 genes were associated with 27.3% of all triple-negative tumors in women 40 years or younger.
CONCLUSIONS AND RELEVANCE: The results of this case-control study suggest that variants in the 9 BC risk genes differ substantially in their associated pathology but are generally associated with triple-negative and/or high-grade disease. Knowing the age and tumor subtype distributions associated with individual BC genes can potentially aid guidelines for gene panel testing, risk prediction, and variant classification and guide targeted screening strategies.