Woolcott Christy G, Maskarinec Gertraud, Pike Malcolm C, Henderson Brian E, Wilkens Lynne R, Kolonel Laurence N
Cancer Research Center of Hawaii, University of Hawaii, 1236 Lauhala Street, Honolulu, HI 96813, USA.
Cancer Causes Control. 2009 Jul;20(5):539-47. doi: 10.1007/s10552-008-9262-2. Epub 2008 Nov 14.
The main objective was to examine the association between simple hysterectomy (without bilateral oophorectomy) and breast cancer risk. Because hysterectomy prevalence varies by ethnicity, the secondary objective was to examine whether inclusion of women with hysterectomies affects the estimates of breast cancer risk by ethnicity.
The Multiethnic Cohort study was assembled between 1993 and 1996 and included 68,065 women from Hawaii and Los Angeles, aged 45-75 years, without any missing information or bilateral oophorectomy. Hysterectomy status was self-reported. After 7.7 years median follow-up, 1,862 cases of invasive breast cancer were identified. Proportional hazards models were used to estimate relative risks (RR) while controlling for known risk factors.
Prevalence of simple hysterectomy varied from 12% to 29% among the ethnic groups (White, African American, Native Hawaiian, Japanese American, and Latina). Overall, hysterectomy was not associated with breast cancer risk (RR = 0.98). Although the RRs were nonsignificantly elevated by 15% in White women and nonsignificantly reduced by 15% in Latinas of non-US origin, the variation by ethnicity was not significant (p(interaction) = 0.48). The breast cancer risk associated with ethnicity was very similar when estimated with and without women with hysterectomies.
This study suggests that simple hysterectomy status does not alter breast cancer risk. Therefore, inclusion of women with simple hysterectomies does not substantially change estimated risk of breast cancer by ethnicity.
主要目的是研究单纯子宫切除术（不包括双侧卵巢切除术）与乳腺癌风险之间的关联。由于子宫切除术的患病率因种族而异，次要目的是研究纳入有子宫切除术的女性是否会影响按种族划分的乳腺癌风险估计。
多民族队列研究于1993年至1996年进行，纳入了来自夏威夷和洛杉矶的68065名年龄在45 - 75岁之间、无任何缺失信息且未进行双侧卵巢切除术的女性。子宫切除术状态由自我报告获得。经过7.7年的中位随访，共确定了1862例浸润性乳腺癌病例。在控制已知风险因素的同时，使用比例风险模型来估计相对风险（RR）。
各民族（白人、非裔美国人、夏威夷原住民、日裔美国人和拉丁裔）中单纯子宫切除术的患病率从12%到29%不等。总体而言，子宫切除术与乳腺癌风险无关（RR = 0.98）。虽然白人女性的RR非显著升高了15%，非美国裔拉丁裔女性的RR非显著降低了15%，但种族差异并不显著（p（交互作用）= 0.48）。在估计有子宫切除术的女性和没有子宫切除术的女性时，与种族相关的乳腺癌风险非常相似。
本研究表明单纯子宫切除术状态不会改变乳腺癌风险。因此，纳入有单纯子宫切除术的女性不会实质性改变按种族划分的乳腺癌估计风险。
