Paganini-Hill A
Department of Preventive Medicine, University of Southern California School of Medicine, Los Angeles 90031.
Semin Surg Oncol. 1994 May-Jun;10(3):158-64. doi: 10.1002/ssu.2980100303.
In all but one of seven recent epidemiologic case-control and cohort studies directly examining the association between aspirin and colorectal cancer and polyps, regular aspirin use reduced the risk of these diseases by about half. Although these studies show a biologically plausible relationship between aspirin and colorectal cancer, information regarding dose and duration and risk change after discontinuation of aspirin is limited and contradictory. Additionally, selection bias, recall bias, and confounding cannot be completed discounted. The one randomized trial of aspirin and placebo showed that aspirin at a dose adequate for preventing myocardial infarction (325 mg every other day) did not reduce colorectal cancer incidence during five years of randomized treatment and follow-up. Further studies need to determine the biologic effects of aspirin, the minimum dose required, and whether other factors, such as age, illnesses, and reasons for aspirin use, modify or confound colorectal cancer development.
在最近七项直接研究阿司匹林与结直肠癌及息肉之间关联的流行病学病例对照研究和队列研究中，除一项研究外，其余所有研究均表明，经常服用阿司匹林可使这些疾病的风险降低约一半。尽管这些研究显示了阿司匹林与结直肠癌之间存在生物学上合理的关系，但关于剂量、持续时间以及停用阿司匹林后的风险变化的信息有限且相互矛盾。此外，选择偏倚、回忆偏倚和混杂因素也不能完全排除。一项阿司匹林与安慰剂的随机试验表明，在五年的随机治疗和随访期间，足以预防心肌梗死的剂量（每隔一天服用325毫克）的阿司匹林并未降低结直肠癌的发病率。进一步的研究需要确定阿司匹林的生物学效应、所需的最小剂量，以及年龄、疾病和使用阿司匹林的原因等其他因素是否会改变或混淆结直肠癌的发展。
