Prospective Evaluation of Risk Factors for Male Breast Cancer

Hormonal and Reproductive Epidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, MD 20852-7234, USA.
Journal of the National Cancer Institute (Impact Factor: 12.58). 10/2008; 100(20):1477-81. DOI: 10.1093/jnci/djn329
Source: PubMed


Most risk factors for male breast cancer have been derived from retrospective studies that may reflect selective recall. In
the prospective National Institutes of Health–AARP Diet and Health Study, we studied 324 920 men, among whom 121 developed
breast cancer. Men who reported a first-degree relative with breast cancer had an increased risk of breast cancer (relative
risk [RR] = 1.92, 95% confidence interval [CI] = 1.19 to 3.09). Among the medical conditions examined, a new finding emerged
regarding increased male breast cancer risk associated with a history of a bone fracture (RR = 2.20, 95% CI = 1.24 to 3.91).
Obesity was positively related to risk (RR = 1.79, 95% CI = 1.10 to 2.91, for body mass indices of ≥30 vs <25 kg/m2) and physical activity inversely related, even after adjustment for body mass index. Smokers were at somewhat elevated risk,
although trends with smoking characteristics were inconsistent. Alcohol consumption was not related to risk. The identified
risk factors show some commonalities with female breast cancer and indicate the importance of hormonal mechanisms. Differences
in risk factors may reflect unique mechanisms associated with androgens and their ratio to bioavailable estrogens.

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Available from: Albert R Hollenbeck, Sep 29, 2015
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    • "Human epidermal growth factor receptor 2 (HER2) over-expression and/or amplification appear less frequent in MBC and the mean age at diagnosis is approximately five years older than for women [2,3,5,6]. Risk factors include hormonal imbalances (for example, caused by liver disease, Klinefelter's syndrome or obesity), genetic predisposition (mainly due to BRCA2 mutations) and environmental factors (for example, exposure to chronic heat or radiation) [7,8]. Survival rates have been debated, with some studies finding that men diagnosed with breast cancer have a worse prognosis than women [9,10], whereas other studies have reported similar prognoses [11,12]. "
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    • "There are some professions which are connected to MBC such as work places with high temperatures and low frequency magnetic fields (Brinton et al., 2008). Prostate cancer is associated with MBC. "
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    ABSTRACT: Male breast cancer is a very rare disease with an incidence of about 0.5-1% comparing with the one of female breast cancer but relatively little is known about its cause. Treatment strategies for breast cancer in males are derived from studies performed among females. The probable reasons behind the frequent, late diagnoses presented at stages III or IV might be the lack of awareness. The rarity of the disease precludes large prospective randomized clinical trials. This study reviews male breast cancer and its risk factors, recommendations for diagnosis and the management of patients with male breast cancer.
    Asian Pacific journal of cancer prevention: APJCP 01/2012; 13(1):15-9. DOI:10.7314/APJCP.2012.13.1.015 · 2.51 Impact Factor
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    • "Data obtained from [3-7]. These references include comprehensive discussion on other considered risk factors for male breast cancer (MBC). "
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    ABSTRACT: Male breast carcinoma is a rare condition. Few male breast cancer-specific epidemiological or clinical trial data are available - our understanding of male breast cancer thus comes from studies of female breast cancer, painting an inaccurate picture when it comes to determining contributing factors. Clinicians report an increase in diagnoses of male breast cancer but this has not been formally reported. We therefore undertook a review of data obtained from four western nations: England, Scotland, Canada and Australia. When adjusted for age, this review clearly showed an increase in the incidence of male breast cancer over a 15-year period. Reasons for the increased incidence are discussed in the context of suggested risk factors such as BRCA2 and lifestyle changes over the past few decades. The clinical management of male breast carcinoma is considered, in particular the potential role of aromatase inhibitors and fulvestrant and targeting pathways involving prolactin and androgen receptor.
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