Wingo P A, Lee N C, Ory H W, Beral V, Peterson H B, Rhodes P
Division of Reproductive Health, Center for Chronic Disease Prevention and Health Promotion, Atlanta, Georgia.
Cancer. 1993 Feb 15;71(4 Suppl):1506-17. doi: 10.1002/cncr.2820710416.
Nearly all studies have suggested that the use of oral contraceptives (OC) is not associated with the aggregate risk of breast cancer diagnosed in women aged 20-54 years. Because of age-specific differences in the breast cancer-parity relationship and because of age-specific differences in other breast cancer risk factors, the Centers for Disease Control reexamined data from the Cancer and Steroid Hormone Study (CASH) to assess whether OC use has different effects on the risk of breast cancer at different ages of diagnosis.
This population-based case-control study was designed to examine the relationship between the use of OC and the risk of breast, ovarian, and endometrial cancer. CASH was conducted in eight geographic areas in the United States during 1980-1982. All participants were interviewed at home with a pretested standardized questionnaire including a calendar of life events and a photograph book of all pills marketed in the United States.
We found that the relationship between the risk of breast cancer and OC use appeared to vary by the age at diagnosis. Among women aged 20-34 years at diagnosis or interview, those who had ever used OC had a slightly increased risk of breast cancer (odds ratio [OR], 1.4; 95% confidence interval [CI], 1.0-2.1) compared with women of the same ages who had never used OC. Among these women, there were no trends of increasing or decreasing risk with any measure of OC use. Among women aged 35-44 years, there was no association between OC use and breast cancer. Among women aged 45-54 years, those who used OC had a slightly decreased risk of breast cancer (OR, 0.9; 95% CI, 0.8-1.0). Among these women, risk estimates decreased significantly with increasing time since first and last use.
Although the slightly increased risk estimates for the youngest women were compatible with findings by other investigators, the decreased risk estimates for the oldest women have not been described in as many studies. Available data provide no reasons to change prescribing practices or the use of OC that are related to the breast cancer risk.
几乎所有研究都表明，使用口服避孕药（OC）与20至54岁女性诊断出乳腺癌的总体风险无关。由于乳腺癌与生育状况关系存在年龄特异性差异，且其他乳腺癌风险因素也存在年龄特异性差异，疾病控制中心重新审视了癌症与类固醇激素研究（CASH）的数据，以评估OC使用在不同诊断年龄对乳腺癌风险是否有不同影响。
这项基于人群的病例对照研究旨在检验OC使用与乳腺癌、卵巢癌和子宫内膜癌风险之间的关系。CASH于1980年至1982年在美国八个地理区域进行。所有参与者都在家中接受了预先测试的标准化问卷调查，问卷包括生活事件日历和美国市场上所有避孕药的照片集。
我们发现，乳腺癌风险与OC使用之间的关系似乎因诊断年龄而异。在诊断或访谈时年龄为20至34岁的女性中，曾经使用过OC的女性患乳腺癌的风险略有增加（优势比[OR]，1.4；95%置信区间[CI]，1.0至2.1），而从未使用过OC的同年龄女性则没有。在这些女性中，无论采用何种OC使用衡量标准，风险均无增加或降低趋势。在35至44岁的女性中，OC使用与乳腺癌之间没有关联。在45至54岁的女性中，使用OC的女性患乳腺癌的风险略有降低（OR，0.9；95%CI，0.8至1.0）。在这些女性中，自首次和最后一次使用以来，随着时间的增加，风险估计值显著降低。
尽管最年轻女性的风险估计值略有增加与其他研究者的发现一致，但年龄最大女性的风险估计值降低在许多研究中并未被描述。现有数据没有理由改变与乳腺癌风险相关的OC处方做法或使用情况。
