饮酒或为东方年轻乳腺癌风险因素
虽然西方人群研究结果已经表明，酒精摄入量与乳腺癌风险成正比，但是对于东方人群，酒精摄入量与乳腺癌风险的小样本研究结果不一。
2021年2月10日，国际抗癌联盟《国际癌症杂志》清样发表日本爱知癌症中心、名古屋大学、北海道大学、爱知医科大学、广岛放射线影响研究所、东北大学、东京国立癌症研究中心、岐阜大学、大阪大学、东京国立国际医疗研究中心、广岛大学、佐贺大学、东京大学的研究报告，对八项人群队列研究进行汇总分析，探讨了日本女性人群酒精摄入量与乳腺癌风险的相关性。
该研究对日本八项大规模人群前瞻队列研究（日本公共卫生中心前瞻研究JPHC-I和JPHC-II、日本协作队列研究JACC、宫城队列研究MIYAGI-I和MIYAGI-II、爱知队列研究AICHI、大崎队列研究OHSAKI、寿命研究LSS）进行汇总分析，评估酒精摄入量（频次和重量）与乳腺癌风险的关联，并根据入组时和诊断时是否绝经进行归类。对各个队列推算风险比和95%置信区间，并通过随机效应模型进行汇总。
结果，研究对象共计15万8164例，随访236万9252人×年，新诊断乳腺癌2208例。
对于入组时未绝经女性：
经常饮酒与从不饮酒相比：乳腺癌风险高37%（风险比：1.37，95%置信区间：1.04～1.81）
每天饮酒≥23克与从不饮酒相比：乳腺癌风险高74%（风险比：1.74，95%置信区间：1.25～2.43）
按频次归类进行趋势分析：P=0.017
对于诊断时未绝经女性：
每天饮酒≥23克与从不饮酒相比：乳腺癌风险高89%（风险比：1.89，95%置信区间：1.04～3.43）
按频次归类进行趋势分析：P=0.032
不过，虽然已绝经女性人数较多且随访时间较长，但是入组时或诊断时酒精摄入量与乳腺癌风险无显著相关性。
因此，该研究结果表明，经常饮酒和大量饮酒都是日本绝经前女性乳腺癌的风险因素，与西方国家既往研究结果相似。不过，日本绝经后女性酒精摄入量与乳腺癌风险缺乏明确相关性，故有必要开展进一步研究对亚洲（尤其中国）女性进行更大规模的调查。
Int J Cancer. 2021 Feb 10. Online ahead of print.
Alcohol consumption and breast cancer risk in Japan: a pooled analysis of eight population-based cohort studies.
Iwase M, Matsuo K, Koyanagi YN, Ito H, Tamakoshi A, Wang C, Utada M, Ozasa K, Sugawara Y, Tsuji I, Sawada N, Tanaka S, Nagata C, Kitamura Y, Shimazu T, Mizoue T, Naito M, Tanaka K, Inoue M.
Aichi Cancer Center Research Institute, Nagoya, Japan; Nagoya University, Nagoya, Japan; Hokkaido University, Sapporo, Japan; Aichi Medical University, Nagakute, Japan; Radiation Effects Research Foundation, Hiroshima, Japan; Tohoku University, Sendai, Japan; National Cancer Center, Tokyo, Japan; Gifu University, Gifu, Japan; Osaka University, Osaka, Japan; National Center for Global Health and Medicine, Tokyo, Japan; Hiroshima University, Hiroshima, Japan; Saga University, Saga, Japan; The University of Tokyo, Tokyo, Japan.
Although alcohol consumption is reported to increase the incidence of breast cancer in European studies, evidence for an association between alcohol and breast cancer in Asian populations is insufficient. We conducted a pooled analysis of eight large-scale population-based prospective cohort studies in Japan to evaluate the association between alcohol (both frequency and amount) and breast cancer risk with categorization by menopausal status at baseline and at diagnosis. Estimated hazard ratios (HR) and 95% confidence intervals were calculated in the individual cohorts and combined using random-effects models. Among 158164 subjects with 2369252 person-years of follow-up, 2208 breast cancer cases were newly diagnosed. Alcohol consumption had a significant association with a higher risk of breast cancer in both women who were premenopausal at baseline (regular drinker compared to nondrinker: HR 1.37, 1.04-1.81, ≥23g/d compared to 0 g/d: HR 1.74, 1.25-2.43, P for trend per frequency category: P = .017) and those who were premenopausal at diagnosis (≥23g/d compared to 0 g/d: HR 1.89, 1.04-3.43, P for trend per frequency category: P = .032). In contrast, no significant association was seen in women who were postmenopausal at baseline or at diagnosis, despite a substantial number of subjects and long follow-up period. Our results revealed that frequent and high alcohol consumption are both risk factors for Asian premenopausal breast cancer, similarly to previous studies in Western countries. The lack of a clear association in postmenopausal women in our study warrants larger investigation in Asia.
KEYWORDS: alcohol; breast cancer; cohort study; pooled analysis
PMID: 33497475
DOI: 10.1002/ijc.33478