Abstract: 【Objective】 To examine the association between alcohol drinking and breast cancer risk. 【Methods】 A hospital -based case -control study was conducted and we recruited a total of 1 268 breast cancer cases and 1 268 controls hospitalized in two affiliated hospitals of Sun Yat -sen University between June 2007 and October 2015. The information on socio -demographic factors

dietary habits

menstrual and reproductive histories

disease and family histories

living habits and physical activity was collected. Multivariate unconditional logistic regression models were used to estimate the association between alcohol drinking and breast cancer risk. 【Results】 The mean (standard deviation) age of cases and controls were 47.35 (9.69) and 47.18 years (9.97)

respectively. And 172 cases (13.6 %) and 104 (8.2 %) controls drank alcohol. We controlled for the factors in the logistic regression models

such as body mass index

education

family income

physical activity

passive smoking

family history of breast cancer

history of benign breast disease and ever used an oral contraceptive use. A positive correlation was found between alcohol drinking and breast cancer risk [odds ratio (OR) = 1.76

95% confidence interval (CI) = 1.35 ~ 2.30)]

with significant dose -response relationships in terms of frequency

duration and amount of alcohol drinking (Ptrend < 0.01). Consumptions of white spirit

grape wine and beer were found to increase the risk of breast cancer.【Conclusion】 This study suggests that alcohol drinking might increase the risk of breast cancer. The effect might only appear in women consumers of white spirit

grape wine and beer.