Alcohol Consumption and Survival after a Breast Cancer Diagnosis: A Literature-Based Meta-analysis and Collaborative Analysis of Data for 29,239 Cases
Authors: Ali Alaa M.G. , Schmidt Marjanka K. , Bolla Manjeet K. , Wang Qin , Gago-Dominguez M. , Castelao J. Esteban , Carracedo Angel , Garzón Victor Muñoz , Bojesen Stig E. , Nordestgaard Børge G. , Flyger Henrik , Chang-Claude Jenny , Vrieling Alina , Rudolph Anja , Seibold Petra , Nevanlinna Heli , Muranen Taru A. , Aaltonen Kirsimari , Blomqvist Carl , Matsuo Keitaro , Ito Hidemi , Iwata Hiroji , Horio Akiyo , John Esther M. , Sherman Mark , Lissowska Jolanta , Figueroa Jonine , Garcia-Closas Montserrat , Anton-Culver Hoda , Shah Mitul , Hopper John L. , Trichopoulou Antonia , Bueno-de-Mesquita Bas , Krogh Vittorio , Weiderpass Elisabete , Andersson Anne , Clavel-Chapelon Françoise , Dossus Laure , Fagherazzi Guy , Peeters Petra H. , Olsen Anja , Wishart Gordon C. , Easton Douglas F. , Borgquist Signe , Overvad Kim , Barricarte Aurelio , González Carlos A. , Sánchez María-José , Amiano Pilar , Riboli Elio , Key Tim , Pharoah Paul D. 
Published: March 2014

Abstract
Background: Evidence for an association of alcohol consumption with prognosis after a diagnosis of breast cancer has been inconsistent. We have reviewed and summarized the published evidence and evaluated the association using individual patient data from multiple case cohorts.
Methods: A MEDLINE search to identify studies published up to January 2013 was performed. We combined published estimates of survival time for “moderate drinkers” versus nondrinkers. An analysis of individual participant data using Cox regression was carried out using data from 11 case cohorts.
Results: We identified 11 published studies suitable for inclusion in the meta-analysis. Moderate postdiagnosis alcohol consumption was not associated with overall survival [HR, 0.95; 95% confidence interval (CI), 0.85–1.05], but there was some evidence of better survival associated with prediagnosis consumption (HR, 0.80; 95% CI, 0.73–0.88). Individual data on alcohol consumption for 29,239 cases with 4,839 deaths were available from the 11 case cohorts, all of which had data on estrogen receptor (ER) status. For women with ER-positive disease, there was little evidence that pre- or postdiagnosis alcohol consumption is associated with breast cancer–specific mortality, with some evidence of a negative association with all-cause mortality. On the basis of a single study, moderate postdiagnosis alcohol intake was associated with a small reduction in breast cancer–specific mortality for women with ER-negative disease. There was no association with prediagnosis intake for women with ER-negative disease.
Conclusion: There was little evidence that pre- or post-diagnosis alcohol consumption is associated with breast cancer–specific mortality for women with ER-positive disease. There was weak evidence that moderate post-diagnosis alcohol intake is associated with a small reduction in breast cancer–specific mortality in ER-negative disease.
Impact: Considering the totality of the evidence, moderate postdiagnosis alcohol consumption is unlikely to have a major adverse effect on the survival of women with breast cancer. Cancer Epidemiol Biomarkers Prev; 23(6); 934–45. ©2014 AACR.