Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
Cancer Causes Control. 2011 Oct;22(10):1415-24. doi: 10.1007/s10552-011-9814-8. Epub 2011 Jul 13.
The contribution of menstrual and reproductive factors to risk of ductal carcinoma (DCIS) of the breast is poorly understood.
The association between menstrual and reproductive factors and subsequent DCIS risk was examined in Women's Health Initiative (WHI) clinical trial participants, in which mammography was protocol mandated. The cohort consisted of 64,060 women, among whom 664 cases of DCIS were ascertained over a median follow-up of 12.0 years. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI).
After adjustment for covariates, only older age at menopause (HR ≥ 55 vs. 45-54 : 1.39, 95% CI 1.08-1.79) was significantly associated with risk; however, greater parity (HR ≥ 5 live births vs. 0: 0.70, 95% CI 0.47-1.03), among parous women, and age at first live birth (HR ≥ 30 years relative to <20 years: 1.32, 95% CI 0.92-1.90) were of borderline significance. Age at menarche and months of breast-feeding were not associated with risk. Associations did not differ between high- and low-/moderate-grade DCIS, or by level of body mass index or family history of breast cancer; however, there was a suggestion that the associations of age at menopause, parity, and age at first live birth were limited to women who had ever used hormone therapy.
Findings from this large cohort of postmenopausal women suggest that age at menopause, and possibly, age at first live birth, and parity are associated with risk of DCIS, whereas age at menarche and duration of breast-feeding are not.
月经和生殖因素对乳腺导管癌（DCIS）风险的影响知之甚少。
在妇女健康倡议（WHI）临床试验参与者中，检查了月经和生殖因素与随后 DCIS 风险之间的关系，其中乳腺 X 线照相术是协议规定的。该队列包括 64060 名女性，其中在中位随访 12.0 年后确定了 664 例 DCIS 病例。使用 Cox 比例风险模型估计风险比（HR）和 95%置信区间（95%CI）。
调整协变量后，仅绝经年龄较大（HR≥55 岁与 45-54 岁：1.39，95%CI 1.08-1.79）与风险显著相关；然而，在多产妇中，较高的生育次数（HR≥5 次活产与 0：0.70，95%CI 0.47-1.03）和首次活产年龄（HR≥30 岁与<20 岁：1.32，95%CI 0.92-1.90）具有边缘意义。初潮年龄和哺乳时间与风险无关。这些关联在高-低/中度 DCIS 之间或在 BMI 水平或乳腺癌家族史之间没有差异；然而，有迹象表明，绝经年龄、生育次数和首次活产年龄的关联仅限于曾使用激素治疗的女性。
这项来自绝经后女性的大型队列研究的结果表明，绝经年龄，可能还有首次活产年龄和生育次数与 DCIS 风险相关，而初潮年龄和哺乳时间与风险无关。
