The trace element selenium is of essential importance for the synthesis of a set of redox active proteins. We investigated three complementary serum selenium status biomarkers in relation to overall survival and recurrence following diagnosis of primary invasive breast cancer in a large prospective cohort study. The Sweden Cancerome Analysis Network – Breast Initiative (SCAN-B) is a prospective population-based study including multiple participating hospitals. Main analyses included 1996 patients with a new diagnosis of primary invasive breast cancer, with blood sampling at the time of diagnosis. In sera of the patients, total serum selenium, selenoprotein P (SELENOP), and glutathione peroxidase 3 (GPx3) activity was analysed. All three biomarkers showed a positive correlation (p < 0.001), supporting the high quality of samples and analytical techniques. During a total of 13,306 person years of follow-up, 310 deaths and 167 recurrent breast cancer events occurred. In fully adjusted Cox models, all three biomarkers correlated inversely with mortality (p _trend <0.001) and compared with the lowest quintile, hazard ratios (95% confidence interval) for overall survival in the highest quintile of selenium, SELENOP and GPx3 were 0.42 (0.28–0.63), 0.51 (0.36–0.73) and 0.52 (0.36–0.75), respectively. Low GPx3 activity was associated with more recurrences (Q5 vs Q1: fully adjusted HR (95%CI); 0.57 (0.35–0.92), (p _trend = 0.005). Patients with low selenium status according to all three biomarkers (triple deficient) had the highest mortality risk with an overall survival probability of ∼50% after 8 years, in particular as compared to those having at least one marker in the highest quintile; fully adjusted HR (95%CI); 0.30 (0.21–0.43). Prediction of mortality based on all three biomarkers outperformed established tumour characteristics like histologic grade, number of involved lymph nodes or tumour size. An assessment of Se status at breast cancer diagnosis identifies patients at exceptionally high risk for a poor prognosis.

微量元素硒对于一组氧化还原活性蛋白的合成至关重要。我们在一项大型前瞻性队列研究中调查了三种互补的血清硒状态生物标志物与原发性浸润性乳腺癌诊断后的总生存期和复发率的关系。瑞典癌症组分析网络 - 乳房倡议 (SCAN-B) 是一项基于人群的前瞻性研究，包括多家参与医院。主要分析包括 1996 名新诊断为原发性浸润性乳腺癌的患者，在诊断时进行了血液采样。在患者的血清中，分析了总血清硒、硒蛋白 P (SELENOP) 和谷胱甘肽过氧化物酶 3 (GPx3) 的活性。所有三种生物标志物均呈正相关（p < 0.001），支持高质量的样品和分析技术。在总共 13,306 人年的随访中，发生了 310 例死亡和 167 例复发性乳腺癌事件。在完全调整的 Cox 模型中，所有三种生物标志物都与死亡率呈负相关（p_趋势<0.001)，与最低五分位数相比，最高五分位数硒、SELENOP 和 GPx3 的总生存风险比 (95% CI) 分别为 0.42 (0.28–0.63)、0.51 (0.36–0.73) 和 0.52 (0.36) –0.75），分别。低 GPx3 活性与更多复发相关（Q5 与 Q1：完全调整后的 HR (95%CI)；0.57 (0.35–0.92)，（p_趋势= 0.005)。根据所有三种生物标志物（三重缺乏），硒状态低的患者死亡风险最高，8 年后总生存概率约为 50%，特别是与那些在最高五分位数中至少有一个标志物的患者相比；完全调整后的 HR (95%CI)；0.30 (0.21–0.43)。基于所有三种生物标志物的死亡率预测优于既定的肿瘤特征，如组织学分级、受累淋巴结数量或肿瘤大小。对乳腺癌诊断时硒状态的评估可以确定患者预后不良的风险极高。