Background:About 15–20% of breast cancers are HER2 positive. Approximately 15–24% of individuals with localized HER2-positive cancer develop metastatic disease after curative treatment, while 3–10% present with de novo metastasis. Survival has significantly improved with various anti-HER2 agents, but there is considerable heterogeneity at the individual level. Our study aims to identify factors influencing survival in de novo metastatic HER2-positive breast cancer using a large sample from the National Cancer Database (NCDB).Methods:Women with metastatic HER2-positive breast cancer diagnosed from 2010 to 2020 in the NCDB were included. Demographic, clinicopathological, treatment data, and overall survival (OS) were collected. Kaplan–Meier curves estimated OS. The log-rank test identified OS differences between groups in univariate analysis. The Cox proportional hazard model with backward elimination identified factors affecting OS in multivariate analysis. The 12-month, 36-month, and 60-month survival estimates, 95% confidence intervals (CIs), and adjusted hazard ratios were reported.Results:Among 5376 women with metastatic HER2-positive breast cancer from 2010 to 2020, the median OS was 55.95 months (95% CI 53.55-NE). Multivariate analysis identified age, Charlson–Deyo comorbidity score, histology, HER2 IHC expression, hormone receptor status, the number of metastatic sites, metastasis location, first-line chemotherapy, anti-HER2 therapy, hormone-blocking therapy, surgery at primary/non-primary sites, and palliative treatment as significant factors affecting OS. Race and radiation receipt were not significant.Conclusions:This is the largest analysis of overall survival estimates in de novo metastatic HER2-positive breast cancer to date in the real-world setting. We identified several independent prognostic factors influencing OS in this population. These findings will help individualize prognostication at diagnosis, optimize treatment strategies, and facilitate patient stratification in future trials.
背景：约15%-20%的乳腺癌为HER2阳性。在接受根治性治疗的局限性HER2阳性乳腺癌患者中，约15%-24%会发展为转移性疾病，而3%-10%的患者在初诊时即存在转移（新发转移）。尽管多种抗HER2药物显著改善了患者生存，但个体间仍存在显著异质性。本研究旨在利用美国国家癌症数据库（NCDB）的大样本数据，探究影响新发转移性HER2阳性乳腺癌患者生存的因素。 方法：纳入NCDB中2010年至2020年诊断为转移性HER2阳性乳腺癌的女性患者。收集人口统计学、临床病理学、治疗数据及总生存期（OS）。采用Kaplan-Meier曲线评估OS，对数秩检验进行单因素分析以识别组间OS差异，通过向后剔除法构建Cox比例风险模型进行多因素分析以确定影响OS的因素。报告12个月、36个月和60个月生存率估计值、95%置信区间（CI）及校正风险比。 结果：在2010年至2020年间的5376例转移性HER2阳性乳腺癌女性患者中，中位OS为55.95个月（95% CI 53.55-未达到）。多因素分析显示，年龄、Charlson-Deyo合并症评分、组织学类型、HER2免疫组化表达水平、激素受体状态、转移灶数量、转移部位、一线化疗、抗HER2治疗、激素阻断治疗、原发灶/非原发灶手术以及姑息治疗是影响OS的显著因素。种族和放疗接受情况未显示显著影响。 结论：这是迄今为止在真实世界环境下对新发转移性HER2阳性乳腺癌患者总生存期进行的最大规模分析。我们确定了影响该人群OS的多个独立预后因素。这些发现将有助于在诊断时实现个体化预后评估，优化治疗策略，并为未来临床试验中的患者分层提供依据。
肿瘤(癌症)患者之家