Zeleniuch-Jacquotte A, Toniolo P, Levitz M, Shore R E, Koenig K L, Banerjee S, Strax P, Pasternack B S
Department of Environmental Medicine, New York University School of Medicine, New York 10010, USA.
Cancer Epidemiol Biomarkers Prev. 1995 Dec;4(8):857-60.
A positive association between postmenopausal serum levels of total estradiol, percentage of free estradiol, and percentage of estradiol not bound to sex hormone-binding globulin (SHBG) and breast cancer risk was recently reported by the New York University Women's Health Study (P. Toniolo et al., J. Natl. Cancer Inst., 87: 190-197, 1995). Data from this prospective study are used to assess whether the observed associations differ according to estrogen receptor (ER) status of the tumor. Between 1985 and 1991, 7063 postmenopausal women donated blood and completed questionnaires at a large breast cancer screening clinic in New York City. Before 1991, 130 cases of first primary breast cancer were identified by active follow-up of the cohort. For each case, two controls were selected, matching the case on age at first blood donation and length of storage of specimens. Biochemical analyses were performed on sera that had been stored at -80 degrees since sampling. ER information was abstracted from pathology reports. Separate statistical analyses were conducted of ER-positive, ER-negative, and ER-unknown groups (53, 23, and 54 matched sets, respectively). In each of the 3 groups, the mean estradiol and the mean percentage of free estradiol were greater (21-28% and 6-7%, respectively) in cases than in controls. Conversely, the mean percentage of estradiol bound to SHBG was 9-12% lower in cases than in controls. The logistic regression coefficients measuring the strength of the association between estradiol and its free and SHBG-bound fractions and breast cancer risk were similar in the ER-positive, ER-negative, and ER-unknown groups. These data suggest that in postmenopausal women, the association of endogenous estrogens with breast cancer risk is independent of the ER status of the tumor. This result is more compatible with the hypothesis of a progression from ER-positive to ER negative tumors than with the hypothesis that ER status identifies two distinct types of breast cancer.
纽约大学妇女健康研究最近报告称，绝经后血清总雌二醇水平、游离雌二醇百分比以及未与性激素结合球蛋白（SHBG）结合的雌二醇百分比与乳腺癌风险之间存在正相关（P. 托尼奥洛等人，《国家癌症研究所杂志》，87: 190 - 197, 1995）。这项前瞻性研究的数据用于评估所观察到的关联是否因肿瘤的雌激素受体（ER）状态而异。1985年至1991年期间，7063名绝经后女性在纽约市一家大型乳腺癌筛查诊所献血并填写问卷。1991年之前，通过对该队列的积极随访确定了130例原发性乳腺癌病例。对于每例病例，选择两名对照，根据首次献血时的年龄和标本储存时间与病例进行匹配。对自采样后一直储存在 -80度的血清进行生化分析。ER信息从病理报告中提取。分别对ER阳性、ER阴性和ER未知组（分别为53、23和54个匹配组）进行统计分析。在这3组中的每组中，病例组的平均雌二醇和游离雌二醇平均百分比均高于对照组（分别高21 - 28%和6 - 7%）。相反，病例组中与SHBG结合的雌二醇平均百分比比对照组低9 - 12%。测量雌二醇及其游离和与SHBG结合部分与乳腺癌风险之间关联强度的逻辑回归系数在ER阳性、ER阴性和ER未知组中相似。这些数据表明，在绝经后女性中，内源性雌激素与乳腺癌风险的关联与肿瘤的ER状态无关。这一结果与从ER阳性肿瘤进展为ER阴性肿瘤的假设比与ER状态识别两种不同类型乳腺癌的假设更相符。
