CIGARETTE SMOKING AND BREAST CANCER: CASE-CONTROL STUDIES OF PREVALENT AND INCIDENT CANCER IN THE CANADIAN NATIONAL BREAST SCREENING STUDY

Abstract Background/Objective: India is the world's most biodiverse region and is undergoing a period of dramatic social and economic change. Due to population's explosion, climate change and lax implementation of environmental policies, the incidence of breast cancer is increasing. From population-based cancer registry data, breast cancer is the most common cancer in women in urban registries where it constitutes more than 30% of all cancers in females. We conducted a meta-analysis of all breast cancer case–control studies conducted in India during 1991–2018 to find pooled estimates of odds ratio (OR). Materials and Methods: Eligible studies were identified through a comprehensive literature search of PubMed, EMBASE, and HINARI databases from 1991 to January 2018. This analysis included 24 observational studies out of 34 that reported the case–control distribution of reproductive factors, body mass index (BMI) and type of residence. The analysis was performed using RevMan 5.3 (Review Manager, 2017) applying the random-effects model. Results: A total of 21,511 patients (9889 cases and 11,622 controls) were analyzed, resulting in statistically significant association between breast cancer and the following reproductive factors: never breastfeed (OR: 3.69; 95% confidence interval [CI]: 1.70, 8.01), menopausal age >50 years (OR: 2.88; 95% CI: 1.85, 3.85), menarche age <13 years (OR: 1.83; 95% CI: 1.34, 2.51), null parity (OR: 1.58; 95% CI: 1.21, 2.06), postmenopause (OR: 1.35; 95% CI: 1.13, 1.62), and age at the 1st pregnancy >25 years (OR: 1.57; 95% CI: 1.37, 1.80). Family history (FH) of breast cancer (OR: 5.33; 95% CI: 2.89, 9.82), obesity (OR: 1.19; 95% CI: 1.00, 1.42), and urban residence (OR: 1.22; 95% CI: 1.03, 1.44) were also found to be significant risk factors. Conclusion: The results of this meta-analysis are indicative of significant associations between reproductive factors and breast cancer risk, profoundly so among women experiencing menopause after the age of 50, women who never breastfeed and FH of breast cancer.

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Serum hormone levels in pre-menopausal Chinese women in Shanghai and white women in Los Angeles: results from two breast cancer case-control studies

Cancer Causes & Control ◽

10.1007/bf00053183 ◽

1990 ◽

Vol 1 (1) ◽

pp. 51-58 ◽

Cited By ~ 87

Author(s):

Leslie Bernstein ◽

Jian-Min Yuan ◽

Ronald K. Ross ◽

Malcolm C. Pike ◽

Rosemarie Hanisch ◽

...

Keyword(s):

Breast Cancer ◽

Los Angeles ◽

White Women ◽

Chinese Women ◽

Breast Cancer Case ◽

Case Control ◽

Cancer Case ◽

Case Control Studies ◽

Hormone Levels ◽

Serum Hormone

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Assessment of a Questionnaire for Breast Cancer Case-Control Studies

Asian Pacific Journal of Cancer Prevention ◽

10.7314/apjcp.2013.14.5.2777 ◽

2013 ◽

Vol 14 (5) ◽

pp. 2777-2782 ◽

Cited By ~ 4

Author(s):

Loreta Strumylaite ◽

Rima Kregzdyte ◽

Danguole Ceslava Rugyte ◽

Algirdas Bogusevicius ◽

Kristina Mechonosina

Keyword(s):

Breast Cancer ◽

Breast Cancer Case ◽

Case Control ◽

Cancer Case ◽

Case Control Studies

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Identification of High-Order Single-Nucleotide Polymorphism Barcodes in Breast Cancer Using a Hybrid Taguchi-Genetic Algorithm: Case-Control Study

JMIR Medical Informatics ◽

10.2196/16886 ◽

2020 ◽

Vol 8 (6) ◽

pp. e16886

Author(s):

Li-Yeh Chuang ◽

Cheng-San Yang ◽

Huai-Shuo Yang ◽

Cheng-Hong Yang

Keyword(s):

Breast Cancer ◽

Genetic Algorithm ◽

Taguchi Method ◽

Case Control Study ◽

Breast Cancer Case ◽

Case Control ◽

High Order ◽

Cancer Case ◽

Single Nucleotide ◽

Control Study

Background Breast cancer has a major disease burden in the female population, and it is a highly genome-associated human disease. However, in genetic studies of complex diseases, modern geneticists face challenges in detecting interactions among loci. Objective This study aimed to investigate whether variations of single-nucleotide polymorphisms (SNPs) are associated with histopathological tumor characteristics in breast cancer patients. Methods A hybrid Taguchi-genetic algorithm (HTGA) was proposed to identify the high-order SNP barcodes in a breast cancer case-control study. A Taguchi method was used to enhance a genetic algorithm (GA) for identifying high-order SNP barcodes. The Taguchi method was integrated into the GA after the crossover operations in order to optimize the generated offspring systematically for enhancing the GA search ability. Results The proposed HTGA effectively converged to a promising region within the problem space and provided excellent SNP barcode identification. Regression analysis was used to validate the association between breast cancer and the identified high-order SNP barcodes. The maximum OR was less than 1 (range 0.870-0.755) for two- to seven-order SNP barcodes. Conclusions We systematically evaluated the interaction effects of 26 SNPs within growth factor–related genes for breast carcinogenesis pathways. The HTGA could successfully identify relevant high-order SNP barcodes by evaluating the differences between cases and controls. The validation results showed that the HTGA can provide better fitness values as compared with other methods for the identification of high-order SNP barcodes using breast cancer case-control data sets.

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The randomized trial of mammography screening that was not—A cautionary tale

Journal of Medical Screening ◽

10.1177/09691413211059461 ◽

2021 ◽

pp. 096914132110594

Author(s):

Martin J Yaffe ◽

Jean M. Seely ◽

Paula B. Gordon ◽

Shushiela Appavoo ◽

Daniel B. Kopans

Keyword(s):

Breast Cancer ◽

Breast Screening ◽

Clinical Breast Examination ◽

Control Group ◽

Multiple Indicators ◽

National Breast ◽

Breast Examination ◽

Screening Study ◽

Clinical Breast ◽

And Performance

Two randomized trials were conducted in Canada in the 1980s to test the efficacy of breast cancer screening. Neither of the trials demonstrated benefit. Concerns were raised regarding serious errors in trial design and conduct. Here we describe the conditions that could allow subversion of randomization to occur and the inclusion of many symptomatic women in a screening trial. We examine anomalies in data where the balance would be expected between trial arms. “Open book” randomization and performance of clinical breast examination on all women before allocation to a trial arm allowed women with palpable findings to be mis-randomized into the mammography arm. Multiple indicators raising suspicion of subversion are present including a large excess in poor-prognosis cancers in the mammography trial arm at prevalence screen. Personnel described shifting of women from the control group into the mammography group. There is compelling evidence of subversion of randomization in Canadian National Breast Screening Study. Mis-randomization of even a few women with advanced breast cancer could markedly affect measured screening efficacy. The Canadian National Breast Screening Study trials should not influence breast screening policies.

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