We aim to provide the most accurate and updated quantification of the effect of cigarette smoking on kidney cancer risk focusing on dose-response relationships.
We conducted a meta-analysis, using an innovative approach combining an umbrella review and a traditional literature search.
Fifty-six original studies were included, providing pooled relative risks (RR) of kidney cancer of 1.39 (95% confidence interval, CI: 1.28-1.51) for current and 1.20 (95% CI: 1.14-1.27) for former compared with never smokers. Kidney cancer risk increased non-linearly with smoking intensity, the RR compared with never smokers being 1.18 (95% CI: 1.11-1.26) for five and 1.72 (95% CI: 1.52-1.95) for 30 cigarettes/day, and increased linearly with smoking duration, the RR being 1.70 (95% CI: 1.10-2.64) after 25 years. The risk linearly decreased with time-since-quitting.
Even smoking few cigarettes per day significantly increases kidney cancer risk. Quitting smoking reduces the risk, the earlier the better.
Critical reviews in oncology/hematology. 2019 Jul 29 [Epub ahead of print]
Xiaoqiu Liu, Giulia Peveri, Cristina Bosetti, Vincenzo Bagnardi, Claudia Specchia, Silvano Gallus, Alessandra Lugo
Department of Environmental Health Sciences, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy., Department of Molecular and Translational Medicine, Università degli Studi di Brescia, Brescia, Italy., Department of Oncology, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy., Department of Statistics and Quantitative Methods, Università degli Studi di Milano-Bicocca, Milan, Italy., Department of Environmental Health Sciences, Istituto di Ricerche Farmacologiche Mario Negri IRCCS, Milan, Italy. Electronic address: .