Impact of Prior Cancer on the Prognosis of Patients With Laryngeal Cancer: A Population-Based Study Using the Surveillance, Epidemiology, and End Results Database.

Little is known about the clinical significance of laryngeal cancer as a subsequent tumor. We aimed to determine the impact of a prior cancer history on the prevalence and prognosis of patients with laryngeal cancer. We retrospectively reviewed patients diagnosed with laryngeal cancer between 2004 and 2011 in the Surveillance, Epidemiology, and End Results (SEER) database. The -test and chi-squared test were used to compare variables as appropriate. Matched 1:1 case control-adjusted Kaplan-Meier analyses and Cox regression models were performed to investigate the impact of prior cancer on overall survival (OS). Among 20,987 patients with laryngeal cancer, nearly one-fifth ( = 3,915, 18.65%) had a prior cancer. The top three common prior cancers were prostate (588, 28.1%), lung and bronchus (354, 16.9%), and head and neck (306, 14.6%). A total of 73.4% of the prior cancers were diagnosed within 5 years of the laryngeal cancer diagnosis. Compared to patients without prior cancer, a worse survival was significantly associated with a prior cancer among laryngeal cancer patients, regardless of the interval time of the prior cancer (log-rank tests < 0.001). Furthermore, prior cancer was an independent predictor of worse OS based on the Cox regression model [hazard ratio (HR) = 1.396, 95% confidence interval, 1.336-1.458]. In addition, patients with prior lung and bronchus cancer tended to have the worst survival (log-rank tests < 0.001). Prior cancer has an adverse effect on clinical outcomes among patients with laryngeal cancer. These results suggest that individualized treatment should be seriously considered in patients with laryngeal cancer and a history of prior cancer, regardless of the interval time of prior cancer.