Smoking, environmental tobacco and renal cell carcinoma: Results from a case-control study

Background: Tobacco use is an established risk factor for renal cell carcinoma (RCC), although little is known regarding the influence of environmental tobacco smoke (ETS). This study assesses the role of tobacco and ETS on RCC incidence using a case-control design. Methods: Incident cases (n = 335) were identified from Florida hospital records and the state cancer registry, and population controls (n = 337) were identified from random-digit dialing. Interviews assessed lifetime consumption of cigarettes and exposure to ETS at home, work, and public/private spaces. Odds ratios and 95% confidence intervals were calculated using logistic regression, controlled for age, sex, race, and BMI. Results: A significant association was found between pack-years and RCC (Wald χ2 = 5.987, p = 0.014). Cases were more likely to have smoked 20 pack-years (OR: 1.48, 95% CI: 1.06-2.07), an association that remained significant only for whites in stratified analyses. A significant protective effect was found for smoking cessation among ex-smokers (Wald χ2 = 17.468, p = 0.000), particularly for 15+ years of cessation (OR: 0.31, 95% CI: 0.18-0.55). Cases were more likely to report home ETS exposure of 20+ years (OR: 1.67; 95% CI: 1.20-2.32), an association that was significant for all groups on stratified analyses by gender and race. Work ETS exposure was significantly associated with RCC only among women, at 15+ years (OR: 1.98; 95% CI: 1.16, 3.38). Conclusion: These findings confirm the known association between tobacco use and RCC and establish a potential etiologic role for ETS, particularly in the home.