Patients with a prior history of cancer are commonly excluded from clinical trial. Increasing number of studies implied that a prior cancer did not adversely affect the clinical outcome among various types of cancer patients. However, the impact of prior cancer on survival of larynx cancer patients remains largely unknown. The aim of this study was to evaluate the prevalence of prior cancer and assess its impact on survival of patients diagnosed with larynx cancer. Patients with larynx cancer as the first or second primary malignancy diagnosed from 2004 to 2015 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. Propensity score matching (PSM) was conducted to balance baseline characteristics. Kaplan-Meier method, multivariate Cox proportional hazard model, and multivariate competing risk model were performed for survival analysis. A total of 24,812 eligible patients with larynx cancer were included in the study, wherein a total of 2436 patients (9.8%) had a prior history of cancer. Prostate (36%), lung and bronchus (10%), urinary bladder (7%), and breast (6%) were the most common types of prior cancer. A prior cancer history served as a risk factor for overall survival (AHR =1.30; 95% CI [1.21–1.41]; P < 0.001) but a protective factor for cancer-specific mortality (AHR = 0.83; 95% CI [0.72–0.94]; P = 0.004) in comparison with those without prior cancer. The subgroup analysis showed that a prior history of cancer adversely affected overall survival of patients with larynx cancer in most subgroups stratified by timing and types of prior cancer, as well as by different clinicopathologic features. Our study indicated an adverse survival impact of a prior history of cancer on patients with larynx cancer. Except for a few particular prior cancer, clinical trials should be considered prudently for laryngeal cancer patients with prior cancers.

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既往癌症史对喉癌患者生存的影响

具有癌症病史的患者通常被排除在临床试验之外。越来越多的研究表明，先前的癌症不会对各种类型的癌症患者的临床结局产生不利影响。然而，先前的癌症对喉癌患者生存的影响仍然未知。这项研究的目的是评估先前癌症的患病率，并评估其对诊断为喉癌的患者生存的影响。从监测，流行病学和最终结果（SEER）数据库中提取2004年至2015年诊断为第一或第二原发恶性喉癌的患者。进行倾向得分匹配（PSM）以平衡基线特征。Kaplan-Meier方法，多元Cox比例风险模型，采用多元竞争风险模型进行生存分析。该研究总共包括24,812名符合条件的喉癌患者，其中共有2436名患者（9.8％）有癌症的既往病史。前列腺癌（36％），肺和支气管（10％），膀胱（7％）和乳腺癌（6％）是最常见的既往癌症类型。既往的癌症病史是整体生存的危险因素（AHR = 1.30； 95％CI [1.21-1.41]； P <0.001），但是癌症特异性死亡率的保护因素（AHR = 0.83； 95％CI [0.72– [0.94]； P = 0.004），与之前没有癌症的患者相比。亚组分析显示，在大多数亚组中，癌症的既往史对喉癌患者的总体生存产生了不利影响，其按先期癌症的时机和类型以及不同的临床病理特征进行了分层。我们的研究表明，癌症的既往史对喉癌患者的生存有不利影响。除少数特定的先前癌症外，对于患有先前癌症的喉癌患者，应谨慎考虑临床试验。