Department of Molecular Medicine and Surgery, Karolinska Institute, Karolinska University Hospital, Stockholm, Sweden.
PLoS One. 2009 Nov 11;4(11):e7695. doi: 10.1371/journal.pone.0007695.
Breast cancer is uncommon in young women and correlates with a less favourable prognosis; still it is the most frequent cancer in women under 40, accounting for 30-40% of all incident female cancer. The aim of this study was to study prognosis in young women, quantifying how much stage at diagnosis and management on the one hand, and tumour biology on the other; each contribute to the worse prognosis seen in this age group.
METHODOLOGY/PRINCIPAL FINDINGS: In a registry based cohort of women aged 20-69 (n = 22 017) with a primary diagnosis of invasive breast cancer (1992-2005), women aged 20-34 (n = 471), 35-39 (n = 858) and 40-49 (n = 4789) were compared with women aged 50-69 years (n = 15 899). The cumulative 5-year relative survival ratio and the relative excess mortality (RER) were calculated. The cumulative 5-year relative survival ratio was lowest in women aged 20-34. The RER was 2.84 for women aged 20-34 and decreased with increasing age (RER 1.76 and 1.17 for women aged 35-39 and 40-49, respectively). The excess risk was, however, present only in disease stages I and II. For women aged 20-34 with stage I disease RER was 4.63, and 6.70 in the subgroup with tumour size 1-10 mm. The absolute difference in stage I between the youngest and the reference groups amounted to nearly 8%, with a 90% 5-year survival in women aged 20-34. In stages IIa and IIb, the relative excess risk was not as dramatic, but the absolute differences approached 15%. The youngest women with small tumours generally received more aggressive treatment than women in older age groups.
After correction for stage, tumour characteristics and treatment, age remained an independent risk factor for breast cancer death in women <35 years of age. The excess risk for young women was only seen in early stages of disease and was most pronounced in women with small tumours. Young women affected by breast cancer have a high risk of dying compared to their middle-aged counterparts even if diagnosed early and receiving an intense treatment.
乳腺癌在年轻女性中较为少见，与预后较差相关；然而，它仍是 40 岁以下女性中最常见的癌症，占所有女性癌症发病的 30-40%。本研究旨在研究年轻女性的预后，定量分析诊断时的分期和治疗以及肿瘤生物学在多大程度上导致该年龄组预后较差。
方法/主要发现：在一项基于登记的 20-69 岁（n = 22017）女性原发性浸润性乳腺癌（1992-2005 年）队列中，将 20-34 岁（n = 471）、35-39 岁（n = 858）和 40-49 岁（n = 4789）的女性与 50-69 岁的女性（n = 15899）进行比较。计算了 5 年累积相对生存率和相对超额死亡率（RER）。20-34 岁女性的 5 年累积相对生存率最低。RER 为 2.84，随着年龄的增加而降低（35-39 岁和 40-49 岁女性的 RER 分别为 1.76 和 1.17）。然而，这种超额风险仅存在于 I 期和 II 期疾病中。对于 20-34 岁 I 期疾病患者，RER 为 4.63，肿瘤大小为 1-10mm 的亚组中为 6.70。年龄最小的女性与参考组之间的 I 期差异几乎达到 8%，20-34 岁女性的 5 年生存率为 90%。在 IIa 和 IIb 期，相对超额风险并不那么显著，但绝对差异接近 15%。肿瘤较小的年轻女性通常接受比老年女性更积极的治疗。
在调整分期、肿瘤特征和治疗后，年龄仍然是 35 岁以下女性乳腺癌死亡的独立危险因素。年轻女性的超额风险仅见于疾病早期，在肿瘤较小的女性中最为明显。与中年女性相比，即使早期诊断并接受强化治疗，患有乳腺癌的年轻女性死亡风险仍然很高。
