Michels K B, Trichopoulos D, Robins J M, Rosner B A, Manson J E, Hunter D J, Colditz G A, Hankinson S E, Speizer F E, Willett W C
Department of Epidemiology, Harvard School of Public Health, Boston, MA 02115, USA.
Lancet. 1996 Dec 7;348(9041):1542-6. doi: 10.1016/S0140-6736(96)03102-9.
The mammary gland is largely undifferentiated before birth and may be particularly susceptible to intrauterine influences that could increase the risk of cancer through acceleration of cell proliferation or other pregnancy-related processes. Studies of migrant populations, animal data, and limited epidemiological evidence suggest that breast cancer may originate in utero. In a nested case-control study we assessed whether birthweight and other perinatal factors are associated with risk of breast cancer.
This case-control study was nested within the cohorts of the two Nurses' Health Studies. We used self-administered questionnaires to obtain information from the mothers of 582 nurses with invasive breast cancer and the mothers of 1569 nurses who did not have breast cancer (controls). Information on risk factors for breast cancer during adulthood were obtained from the nurses; multiple logistic regression analysis adjusted for these risk factors.
Birthweight was a significant predictor of breast-cancer risk. With women who weighed 4000 g or more at birth as the reference category, the adjusted odds ratios for breast cancer were 0.86 (95% CI 0.59-1.25) for birthweights of 3500-3999 g, 0.68 (0.48-0.97) for birthweights of 3000-3499 g, 0.66 (0.45-0.98) for birthweights of 2500-2999 g, and 0.55 (0.33-0.93) for birthweights below 2500 g (p for trend 0.004). Prematurity was not significantly associated with risk of breast cancer.
Birthweight is significantly associated with breast-cancer risk, which suggests that intrauterine factors or processes affect the risk of breast cancer in the offspring. High concentrations of pregnancy oestrogens may have an important role in breast carcinogenesis, but other pregnancy hormones or intrauterine factors may also be involved.
乳腺在出生前基本未分化，可能特别容易受到子宫内因素的影响，这些因素可能通过加速细胞增殖或其他与妊娠相关的过程增加患癌风险。对移民人群的研究、动物数据以及有限的流行病学证据表明，乳腺癌可能起源于子宫内。在一项巢式病例对照研究中，我们评估了出生体重和其他围产期因素是否与乳腺癌风险相关。
这项病例对照研究嵌套在两项护士健康研究的队列中。我们使用自填式问卷从582名浸润性乳腺癌护士的母亲和1569名未患乳腺癌的护士（对照）的母亲那里获取信息。从护士那里获得成年期乳腺癌风险因素的信息；对这些风险因素进行多因素逻辑回归分析。
出生体重是乳腺癌风险的重要预测因素。以出生时体重4000克或以上的女性为参照组，出生体重为3500 - 3999克的女性患乳腺癌的校正比值比为0.86（95%可信区间0.59 - 1.25），出生体重为3000 - 3499克的为0.68（0.48 - 0.97），出生体重为2500 - 2999克的为0.66（0.45 - 0.98），出生体重低于2500克的为0.55（0.33 - 0.93）（趋势p值为0.004）。早产与乳腺癌风险无显著关联。
出生体重与乳腺癌风险显著相关，这表明子宫内因素或过程会影响后代患乳腺癌的风险。孕期高浓度雌激素可能在乳腺癌发生过程中起重要作用，但其他孕期激素或子宫内因素也可能参与其中。
