Abstract

Background

Breast cancer is rare in men, and information on its causes is very limited from studies that have generally been small. Adult obesity has been shown as a risk factor, but more detailed anthropometric relations have not been investigated.

Methods

We conducted an interview population-based case-control study of breast cancer in men in England and Wales including 1998 cases incident during 2005-2017 at ages younger than 80 years and 1597 male controls, with questions asked about a range of anthropometric variables at several ages. All tests of statistical significance were 2-sided.

Results

Risk of breast cancer statistically significantly increased with increasing body mass index (BMI) at ages 20 (odds ratio [OR] = 1.07, 95% confidence interval [CI] = 1.02 to 1.12 per 2-unit change in BMI), 40 (OR = 1.11, 95% CI = 1.07 to 1.16), and 60 (OR = 1.14, 95% CI = 1.09 to 1.19) years, but there was also an indication of raised risk for the lowest BMIs. Large waist circumference 5 years before interview was more strongly associated than was BMI with risk, and each showed independent associations. Associations were similar for invasive and in situ tumors separately and stronger for HER2-positive than HER2-negative tumors. Of the tumors, 99% were estrogen receptor positive.

Conclusions

Obesity at all adult ages, particularly recent abdominal obesity, is associated with raised risk of breast cancer in men, probably because of the conversion of testosterone to estrogen by aromatase in adipose tissue. The association is particularly strong for HER2-expressing tumors.

Details

Title
Obesity and Breast Cancer Risk in Men: A National Case-Control Study in England and Wales
Author
Swerdlow, Anthony J 1 ; Bruce, Cydney 2 ; Cooke, Rosie 3 ; Coulson, Penny 4 ; Griffin, James 5 ; Butlin, Alison 4 ; Smith, Beverley 4 ; Swerdlow, M Jill 4 ; Jones, Michael E 4 

 Division of Genetics and Epidemiology, The Institute of Cancer Research, London, UK; Division of Breast Cancer Research, The Institute of Cancer Research, London, UK 
 Division of Genetics and Epidemiology, The Institute of Cancer Research, London, UK; Nottingham Clinical Trials Unit, School of Medicine, University of Nottingham, Nottingham, UK 
 Division of Genetics and Epidemiology, The Institute of Cancer Research, London, UK; Department of Oncology, University of Oxford, Oxford, UK 
 Division of Genetics and Epidemiology, The Institute of Cancer Research, London, UK 
 Division of Genetics and Epidemiology, The Institute of Cancer Research, London, UK; Warwick Clinical Trials Unit, Warwick Medical School, University of Warwick, Coventry, UK 
Publication year
2021
Publication date
Oct 2021
Publisher
Oxford University Press
e-ISSN
25155091
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
3170601856
Copyright
© The Author(s) 2021. Published by Oxford University Press. This work is published under https://creativecommons.org/licenses/by-nc/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.