Alcohol consumption and survival after breast cancer diagnosis in Japanese women

It is unclear whether alcohol consumption may impact survival after breast cancer diagnosis. To clarify the association between pre-treatment alcohol consumption and survival in breast cancer patients, a prospective patient cohort study was conducted.
The cohort comprised 1,420 breast cancer patients diagnosed during 1997–2013 at a single institute in Japan. Alcohol drinking and other lifestyle factors were assessed by questionnaire survey at the initial admission. The patients were followed until December 31, 2016.
During a median follow-up period of 8.6 years, 261 all-cause and 193 breast cancer-specific deaths were documented. Survival curves showed that ever-drinkers tended to have better survival than never-drinkers (breast cancer-specific survival). Better survival was also observed for light drinkers with an intake of <5.0 g per day. In the Cox model, ever-drinking was associated with a decreased risk of all-cause (HR: 0.75; 95% CI: 0.54–1.05) and
breast cancer-specific death (HR: 0.68; 95% CI: 0.46–0.99). Light drinkers had a lower risk of breast cancer-specific death (frequency of drinking, HR
= 0.57 for occasional or 1–2 times per week and
0.72 for 3–7 times per week; amount of alcohol consumed per day, HR = 0.57 for <5.0 g and 0.68 for
≥5.0 g compared with never-drinking). In terms of hormone receptor status, a significantly decreased risk of death associated with ever-drinking was observed among women with receptor-negative cancer (ER-/PR-, HR = 0.41; 95% CI: 0.20–0.84 for
breast cancer-specific death).
The authors conclude that pretreatment, i.e., pre- diagnosis alcohol consumption is unlikely to have an adverse effect on survival after breast cancer diagnosis. Light alcohol consumption may have a beneficial effect on patient survival.
Source: Alcohol consumption and survival after breast cancer diagnosis in Japanese women: A prospective patient cohort study. Y Minami, S Kanemura, M Kawai, Y Nishino, H Tada, M Miyashita, T Ishida, Y Kakugawa.PLOS One, Published: November 13, 2019.