Gender is a non-negligible risk factor affecting the overall survival time of NSCLC patients: a nationwide population-based study

Abstract Purpose: The aim of this study is to explore the effect of gender on overall survival (OS) in non–small cell lung cancer (NSCLC) patients. Methods: The Surveillance, Epidemiology, and End Results Database (SEER) was queried for NSCLC cases from 2004 to 2015. A total of 129,864 NSCLC patients were identified to enroll in our study, including 78,460 males and 51,404 females. We compared and analyzed the demographics, socioeconomics, regional differences, tumor characteristics, treatment, and survival time in both groups of patients. Results: Kaplan-Meier analysis showed improved OS in the female group compared to the male group throughout all stages (P<0.001). Median OS for males were 33.00 (95%CI: 31.88-34.12), 23.00 (95%CI: 21.93-24.07), 11.00 (95%CI: 10.77-11.23), and 4.00 (95%CI: 3.90-4.10) months from stage IB to IV, respectively. Median OS for females were 52.00 (95%CI: 49.53-54.47), 30.00 (95%CI: 27.95-32.05), 13.00 (95%CI: 12.63-13.37), 5.00 (95%CI: 4.85-5.15) months respectively as counterparts. A multivariable Cox regression model was constructed and analyzed on survival for each clinical stage. Being in the female cohort could significantly reduce risks for mortality compared with male cohort at all stages (hazard ratios [HR] of 0.766, 0.797, 0.846, and 0.857 for stages IB through IV respectively, [all P< 0.001]). Conclusions: For various stages of patients older than 45 years, the OS of female NSCLC patients with or without chemotherapy is greater than that for male counterparts. Gender is a non-negligible risk factor affecting the overall survival time of NSCLC patients.