Background

It is not clear how the pathology, presentation and outcome for patients who present with de novo metastatic breast cancer (dnMBC) compare with those who later develop distant metastases. DnMBC is uncommon in younger patients. We describe these differences within a cohort of young patients in the United Kingdom.

Methods

Women aged 40 years or younger with a first invasive breast cancer were recruited to the prospective POSH national cohort study. Baseline clinicopathological data were collected, with annual follow-up. Overall survival (OS) and post-distant relapse-free survival (PDRS) were assessed using Kaplan–Meier curves.

Results

In total, 862 patients were diagnosed with metastatic disease. DnMBC prevalence was 2.6% (76/2977). Of those with initially localised disease, 27.1% (786/2901) subsequently developed a distant recurrence. Median follow-up was 11.00 years (95% CI 10.79–11.59). Patients who developed metastatic disease within 12 months had worse OS than dnMBC patients (HR 2.64; 1.84–3.77). For PDRS, dnMBC was better than all groups, including those who relapsed after 5 years. Of dnMBC patients, 1.3% had a gBRCA1, and 11.8% a gBRCA2 mutation.

Conclusions

Young women with dnMBC have better PDRS than those who develop relapsed metastatic breast cancer. A gBRCA2 mutation was overrepresented in dnMBC.

中文翻译：

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在一批年轻患者中从头生存与复发转移性乳腺癌的生存率和疾病特征。

背景

尚不清楚从头转移性乳腺癌（dnMBC）的患者与后来发生远处转移的患者的病理，表现和结果如何比较。DnMBC在年轻患者中并不常见。我们在英国一群年轻患者中描述了这些差异。

方法

40岁或以下患有首次浸润性乳腺癌的女性被纳入前瞻性POSH国家队列研究。收集基线临床病理数据，并进行年度随访。使用Kaplan–Meier曲线评估了总生存期（OS）和远距离无复发生存期（PDRS）。

结果

总共862名患者被诊断出患有转移性疾病。DnMBC患病率为2.6％（76/2977）。在最初患有局部疾病的患者中，27.1％（786/2901）随后发生了远处复发。中位随访时间为11.00年（95％CI 10.79-11.59）。在12个月内发生转移性疾病的患者的OS较dnMBC患者差（HR 2.64； 1.84-3.77）。对于PDRS，dnMBC优于所有组，包括5年后复发​​的组。在dnMBC患者中，有1.3％的人患有BRCA1突变，有11.8％的人患有BRCA2突变。

结论

与发展复发性转移性乳腺癌的女性相比，患有dnMBC的年轻女性的PDRS更好。gBRCA2突变在dnMBC中代表过多。