Pujol P, Hilsenbeck S G, Chamness G C, Elledge R M
Unité 148 INSERM, Montpellier, France.
Cancer. 1994 Sep 1;74(5):1601-6. doi: 10.1002/1097-0142(19940901)74:5<1601::aid-cncr2820740517>3.0.co;2-#.
The incidence of estrogen receptor (ER)-positive breast cancer apparently is increasing. It remains unclear whether this increase is due to an improvement in receptor assay sensitivity, a change in patient characteristics, or a change in tumor biology.
The distribution of ER, tumor size, and patient age for 11,195 tumor specimens gathered from patients nationwide from 1973 to 1992 were analyzed. All assays were performed in a single laboratory. A single-label, dextran-coated charcoal (DCC) method was used from 1973 to 1984, and a dual-label, DCC method, which allows the determination of both ER and progesterone receptor levels in the same assay, was used from 1985 to 1992.
The median level of ER has increased steadily from 14 fmol per milligram of protein in 1973 to 58 fmol per milligram of protein in 1992 (P < 0.0001). The percentage of ER-positive tumors also rose from 73-78% during the same period (P = 0.008). When the assay method was modified from single to dual label, no abrupt or stepwise increase occurred. Tumor size decreased over the same period (P < 0.0001). From 1973 to 1977, 48% of tumors were larger than 2 cm, and 15% were larger than 5 cm, compared to 60% and 9%, respectively, from 1988 to 1992. The percentage of women older than 50 years of age remained relatively constant over time. After adjusting for tumor size, age, number of positive lymph nodes, and change in assay method, a sustained rise in ER level remained. In a multivariate analysis that included age, age group, year of biopsy, tumor size, and number of positive nodes, the year of biopsy still was independently predictive of ER level (P < 0.0001).
The measured level of ER in primary breast cancers has increased during the last 2 decades. It is unlikely that technical improvements or changes in tumor size, age, or nodal status fully explain this increase. The rising level of ER may reflect a change in breast cancer biology and in hormonal events that influence breast cancer genesis and growth.
雌激素受体（ER）阳性乳腺癌的发病率明显呈上升趋势。目前尚不清楚这种上升是由于受体检测灵敏度的提高、患者特征的变化还是肿瘤生物学特性的改变。
分析了1973年至1992年从全国患者收集的11195份肿瘤标本的ER、肿瘤大小和患者年龄分布情况。所有检测均在单一实验室进行。1973年至1984年采用单标记葡聚糖包被活性炭（DCC）法，1985年至1992年采用双标记DCC法，该方法可在同一检测中同时测定ER和孕激素受体水平。
ER的中位数水平从1973年的每毫克蛋白质14飞摩尔稳步上升至1992年的每毫克蛋白质58飞摩尔（P<0.0001）。同期ER阳性肿瘤的百分比也从73%-78%上升（P=0.008）。当检测方法从单标记改为双标记时，未出现突然或逐步上升的情况。同期肿瘤大小减小（P<0.0001）。1973年至1977年，48%的肿瘤大于2厘米，15%大于5厘米，而1988年至1992年分别为60%和9%。50岁以上女性的百分比随时间相对保持稳定。在调整肿瘤大小、年龄、阳性淋巴结数量和检测方法的变化后，ER水平仍持续上升。在包括年龄、年龄组、活检年份、肿瘤大小和阳性淋巴结数量的多变量分析中，活检年份仍然独立预测ER水平（P<0.0001）。
在过去20年中，原发性乳腺癌中测得的ER水平有所上升。技术改进或肿瘤大小、年龄或淋巴结状态的变化不太可能完全解释这种上升。ER水平的上升可能反映了乳腺癌生物学特性以及影响乳腺癌发生和生长的激素事件的变化。
