REVIEW
Epidemiology and Pathophysiology of Alcohol and Breast Cancer: Update 2012
Helmut K. Seitz
1,2,
*
, Claudio Pelucchi
3
, Vincenzo Bagnardi
4,5
and Carlo La Vecchia
3,6,7
1
Centre of Alcohol Research, University of Heidelberg, Heidelberg, Germany,
2
Department of Medicine, Salem Medical Centre, Zeppelinstr. 11-33,
Heidelberg 69121, Germany,
3
Mario Negri Institute for Pharmacological Research, Milan, Italy,
4
Department of Statistics, University of Milano-Bicocca,
Milan, Italy,
5
Division of Epidemiology and Biostatistics, European Institute of Oncology, Milan, Italy,
6
International Prevention Research Institute, Lyon,
France and
7
Department of Occupational Health, University of Milano, Milan, Italy
*Corresponding author: Tel.: +49-6221-483200; Fax: +49-6221-483494; E-mail: [email protected]
(
Received
20
December
2011;
accepted
9
January
2012)
Abstract
—
Aims:
To update epidemiological data on alcohol and breast cancer, with special emphasis on light alcohol consump-
tion, and to review mechanisms of alcohol mediated mammary carcinogenesis.
Methods:
For epidemiological data, in November
2011 we performed a literature search in various bibliographic databases, and we conducted a meta-analysis of data on light alcohol
drinking. Relevant mechanistic studies were also reviewed to November 2011.
Results:
A significant increase of the order of 4% in
the risk of breast cancer is already present at intakes of up to one alcoholic drink/day. Heavy alcohol consumption, defined as three
or more drinks/day, is associated with an increased risk by 40
–
50%. This translates into up to 5% of breast cancers attributable to
alcohol in northern Europe and North America for a total of approximately 50 000 alcohol-attributable cases of breast cancer world-
wide. Up to 1
–
2% of breast cancers in Europe and North America are attributable to light drinking alone, given its larger prevalence
in most female populations when compared with heavy drinking. Alcohol increases estrogen levels, and estrogens may exert its car-
cinogenic effect on breast tissue either via the ER or directly. Other mechanisms may include acetaldehyde, oxidative stress, epigen-
etic changes due to a disturbed methyl transfer and decreased retinoic acid concentrations associated with an altered cell cycle.
Conclusions:
Women should not exceed one drink/day, and women at elevated risk for breast cancer should avoid alcohol or
consume alcohol occasionally only.
GENERAL INTRODUCTION
Alcohol consumption is a risk factor for cancer of various
organs including the upper alimentary tract, the liver, the col-
orectum and the female breast (
Seitz and Stickel, 2007
).
Among these organs, ethanol-mediated mammary carcino-
genesis seems different since even small doses of ethanol
stimulate breast cancer development. This is of considerable
concern since in Europe and in the USA breast cancer is the
most common cancer in women and alcohol use is wide-
spread. In this review, up to date epidemiological data on
alcohol and breast cancer have been analyzed with special
emphasis on light alcohol consumption. In addition, possible
