Bouchardy Christine, Verkooijen Helena M, Fioretta Gérald
Geneva Cancer Registry, Institute for Social and Preventive Medicine, University of Geneva, Switzerland.
Int J Cancer. 2006 Sep 1;119(5):1145-51. doi: 10.1002/ijc.21889.
Reasons of the important impact of socioeconomic status on breast cancer prognosis are far from established. This study aims to evaluate and explain the social disparities in breast cancer survival in the Swiss canton of Geneva, where healthcare costs and life expectancy are among the highest in the world. This population-based study included all 3,920 female residents of Geneva, who were diagnosed with invasive breast cancer before the age of 70 years between 1980 and 2000. Patients were divided into 4 socioeconomic groups, according to the woman's last occupation. We used Cox multivariate regression analysis to identify reasons for the socioeconomic inequalities in breast cancer survival. Compared to patients of high social class, those of low social class had an increased risk (unadjusted hazard ratio [HR] 2.4, 95% CI: 1.6-3.5) of dying as a result of breast cancer. These women were more often foreigners, less frequently had screen-detected cancer and were at more advanced stage at diagnosis. They less frequently underwent breast-conserving surgery, hormonal therapy, and chemotherapy, in particular, in case of axillary lymph node involvement. When adjusting for all these factors, patients of low social class still had a significantly increased risk of dying of breast cancer (HR 1.8, 95% CI: 1.2-2.6). Overmortality linked to low SES is only partly explained by delayed diagnosis, unfavorable tumor characteristics and suboptimal treatments. Other factors, not measured in this study, also could play a role. While waiting for the outcome of other researches, we should consider socioeconomic status as an independent prognostic factor and provide intensified support and surveillance to women of low social class.
社会经济地位对乳腺癌预后产生重要影响的原因尚未完全明确。本研究旨在评估并解释瑞士日内瓦州乳腺癌生存方面的社会差异，该州的医疗成本和预期寿命位居世界前列。这项基于人群的研究纳入了1980年至2000年间在日内瓦被诊断为70岁之前的浸润性乳腺癌的所有3920名女性居民。根据女性的最后职业，将患者分为4个社会经济组。我们使用Cox多变量回归分析来确定乳腺癌生存中社会经济不平等的原因。与高社会阶层的患者相比，低社会阶层的患者因乳腺癌死亡的风险增加（未调整风险比[HR] 2.4，95%置信区间：1.6 - 3.5）。这些女性更多为外国人，通过筛查发现癌症的频率较低，诊断时处于更晚期。她们较少接受保乳手术、激素治疗和化疗，尤其是在腋窝淋巴结受累的情况下。在对所有这些因素进行调整后，低社会阶层的患者死于乳腺癌的风险仍然显著增加（HR 1.8，95%置信区间：1.2 - 2.6）。与低社会经济地位相关的超额死亡率仅部分由诊断延迟、不良肿瘤特征和治疗不充分所解释。本研究未测量的其他因素也可能起作用。在等待其他研究结果的同时，我们应将社会经济地位视为一个独立的预后因素，并为低社会阶层的女性提供强化支持和监测。
