Occupational Exposures and Cancer of the Larynx—Systematic Review and Meta-analysis

Objective: To review epidemiologic data on occupational exposures and laryngeal cancer. Methods: We performed a systematic literature search and a series of meta-analyses for agents with at least 10 available studies with homogenous exposure. Results: We analyzed 99 publications. Significantly increased meta-relative risks (meta-RRs) were obtained considering exposure to polycyclic aromatic hydrocarbons (meta-RR 1.29; 95% confidence interval [CI] 1.10 to 1.52), engine exhaust (meta-RR 1.17; 95% CI 1.05 to 1.30), textile dust (meta-RR 1.41; 95% CI 1.09 to 1.83), and working in the rubber industry (meta-RR 1.39; 95% CI 1.13 to 1.71). Exposures to wood dust, formaldehyde, and cement dust were not significantly associated with laryngeal cancer. In regards of the epidemiologic available data, we could not conclude on the role of solvents. Conclusion: Further studies should overcome past limitations in terms of exposure characterization, adjustment for confounding, and sample size.