The prognostic role of cigarette smoking in Kidney Cancer Survival

BACKGROUND: The role of cigarette smoking as a prognostic factor for kidney cancer (KC) is unclear. In this population‐based study, we analyze cancer‐specific survival (CSS) outcomes among KC patients by smoking status at diagnosis in the diverse state of Florida. METHODS: All primary KC cases from the Florida Cancer Registry diagnosed during 2005–2018 were analyzed. Cox proportional regression was conducted to assess the determinants of KC survival, including age, sex, race/ethnicity, socioeconomic status, histology type, cancer stage, and treatment received with a particular focus on smoking status (smokers at diagnosis referred to as current smokers, former smokers, and never smokers). RESULTS: Among all 36,150 KC patients, 18.3% were smokers at diagnosis (n = 6629), 32.9% were former smokers (n = 11,870), and 48.8% were never smokers (n = 17,651). Age‐standardized five‐year survival for current, former, and never smokers was 65.3 (95% CI: 64.1–66.5), 70.6 (95% CI: 69.7–71.5), and 75.3 (95% CI: 74.6–76.0) respectively. In multivariable analysis, current and former smokers had an estimated 30% and 14% higher risk of KC death compared to never smokers, respectively, after adjusting for potential confounders (HR: 1.30, 95% CI: 1.23–1.40; HR: 1.14, 95% CI: 1.10–1.20). CONCLUSION: Smoking independently contributes to poorer survival, across all KC stages. Clinicians should encourage and facilitate participation in cigarette smoking cessation programs targeted at current smokers. Prospective studies are warranted to assess the role of different types of tobacco use and cessation programs on KC survival.