Beresford S A, Weiss N S, Voigt L F, McKnight B
Departments of Epidemiology, University of Washington, Seattle 98195-7236, USA.
Lancet. 1997 Feb 15;349(9050):458-61. doi: 10.1016/S0140-6736(96)07365-5.
Postmenopausal oestrogen therapy reduces the risk of osteoporosis and cardiovascular diseases but is associated with an increased risk of endometrial cancer. We have assessed the impact of a regimen of oestrogen with cyclic progestagen on risk of endometrial cancer for postmenopausal women.
We did a population-based case-control study of women aged 45-74 years in western Washington State, USA. Cases were identified from a regional cancer registry as having histologically confirmed endometrial cancer during 1985-91. 832 (72%) of 1154 eligible cases completed interviews. Controls were identified by random digit dialling, screened for intact uterus, frequency matched for age and county, and randomly assigned a reference date within 1985-91. Interviews with 1114 (73%) of 1526 eligible controls were done. The women provided information about use of hormone replacement therapy, and reproductive and medical history before diagnosis date (cases) or reference date (controls).
Relative to women who had never used hormones (for > 6 months), women who had taken unopposed oestrogen had a four-fold increase (95% CI 3.1-5.1) in risk of endometrial cancer. Women who used a combined therapy of oestrogen with cyclic progestagen (eg. medroxyprogesterone acetate) had a relative risk of 14 (1.0-1.9). Among women with fewer than 10 days of added progestagen per month, the relative risk was 3.1 (1.7-5.7). Whereas that for women with 10-21 days of added progestagen was 1.3 (0.8-2.2). The use of these combined regimens for 5 or more years was associated with risks of 3.7 (1.7-8.2) and 2.5 (1.1-5.5), respectively, relative to non-users of hormones.
Postmenopausal women who use combined therapy of oestrogen with cyclic progestagen on a long-term basis have an increased risk of endometrial cancer compared with those who are not on hormone replacement, even when progestagen is added for 10 or more days per month. This increase is much smaller than that associated with unopposed oestrogen, but needs to be confirmed.
绝经后雌激素治疗可降低骨质疏松症和心血管疾病的风险，但与子宫内膜癌风险增加有关。我们评估了雌激素联合周期性孕激素方案对绝经后女性子宫内膜癌风险的影响。
我们在美国华盛顿州西部对45 - 74岁的女性进行了一项基于人群的病例对照研究。病例是从区域癌症登记处确定的，在1985 - 1991年期间经组织学确诊为子宫内膜癌。1154例符合条件的病例中有832例（72%）完成了访谈。对照通过随机数字拨号确定，筛选出子宫完整的女性，按年龄和县区进行频率匹配，并在1985 - 1991年内随机分配一个参考日期。对1526例符合条件的对照中的1114例（73%）进行了访谈。这些女性提供了关于激素替代疗法的使用情况以及诊断日期（病例）或参考日期（对照）之前的生殖和病史信息。
与从未使用过激素（超过6个月）的女性相比，使用单纯雌激素的女性患子宫内膜癌的风险增加了四倍（95%置信区间3.1 - 5.1）。使用雌激素联合周期性孕激素（如醋酸甲羟孕酮）的女性相对风险为1.4（1.0 - 1.9）。在每月添加孕激素少于10天的女性中，相对风险为3.1（1.7 - 5.7）。而每月添加孕激素10 - 21天的女性相对风险为1.3（0.8 - 2.2）。与未使用激素的女性相比，使用这些联合方案5年或更长时间的相对风险分别为3.7（1.7 - 8.2）和2.5（1.1 - 5.5）。
与未接受激素替代治疗的绝经后女性相比，长期使用雌激素联合周期性孕激素治疗的绝经后女性患子宫内膜癌的风险增加，即使每月添加孕激素10天或更长时间。这种增加远小于单纯使用雌激素相关风险，但仍需进一步证实。
