Sun Xuezheng, Nichols Hazel B, Tse Chiu-Kit, Bell Mary B, Robinson Whitney R, Sherman Mark E, Olshan Andrew F, Troester Melissa A
Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina. Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina.
Cancer Epidemiol Biomarkers Prev. 2016 Jan;25(1):60-7. doi: 10.1158/1055-9965.EPI-15-0864. Epub 2015 Nov 6.
Parity and time since last birth influence breast cancer risk and vary by intrinsic tumor subtype, but the independent effects of these factors on prognosis have received limited attention.
Study participants were 1,140 invasive breast cancer patients from phases I and II of the population-based Carolina Breast Cancer Study, with tissue blocks available for subtyping using immunohistochemical markers. Breast cancer risk factors, including pregnancy history, were collected via in-person interviews administered shortly after diagnosis. Vital status was determined using the National Death Index. The association of parity and birth recency with breast cancer-specific and overall survival was assessed using Cox proportional hazards models.
During follow-up (median = 13.5 years), 450 patients died, 61% due to breast cancer (n = 276). High parity (3+ births) and recent birth (<5 years before diagnosis) were positively associated with breast cancer-specific mortality, independent of age, race, and selected socioeconomic factors [parity, reference = nulliparous, adjusted HR = 1.76; 95% confidence interval (CI) = 1.13-2.73; birth recency, reference = 10+ years, adjusted HR = 1.29; 95% CI, 0.79-2.11]. The associations were stronger among patients with luminal tumors and those surviving longer than 5 years.
Parity and recent birth are associated with worse survival among breast cancer patients, particularly among luminal breast cancers and long-term survivors.
The biologic effects of parity and birth recency may extend from etiology to tumor promotion and progression.
生育胎次及上次生育后的时间会影响乳腺癌风险，且因肿瘤内在亚型而异，但这些因素对预后的独立影响受到的关注有限。
研究参与者为来自基于人群的卡罗来纳乳腺癌研究第一和第二阶段的1140例浸润性乳腺癌患者，有组织块可使用免疫组化标记进行亚型分类。通过诊断后不久进行的面对面访谈收集包括妊娠史在内的乳腺癌危险因素。使用国家死亡指数确定生命状态。使用Cox比例风险模型评估生育胎次和最近生育情况与乳腺癌特异性生存和总生存的关联。
在随访期间（中位时间 = 13.5年），450例患者死亡，61%死于乳腺癌（n = 276）。高生育胎次（3次及以上生育）和最近生育（诊断前<5年）与乳腺癌特异性死亡率呈正相关，独立于年龄、种族和选定的社会经济因素[生育胎次，参照 = 未生育，调整后HR = 1.76；95%置信区间（CI）= 1.13 - 2.73；最近生育情况，参照 = 10年及以上，调整后HR = 1.29；95% CI，0.79 - 2.11]。在管腔型肿瘤患者和存活超过5年的患者中，这些关联更强。
生育胎次和最近生育与乳腺癌患者生存较差相关，尤其是在管腔型乳腺癌患者和长期存活者中。
生育胎次和最近生育的生物学效应可能从病因学延伸至肿瘤促进和进展。
