Laryngeal cancer and silica dust exposure: a systematic review and meta-analysis

Am J Ind Med. 2012 Aug;55(8):669-76. doi: 10.1002/ajim.22037. Epub 2012 Mar 27.


Background: Individual epidemiological studies generally lack the power to examine the association between silica exposure or silicosis and laryngeal cancer. We summarized pertinent evidence from published literature by using meta-analysis.

Methods: A systematic literature search was performed to identify cohort and case-control studies, and the method of meta-analysis was used to combine standardized mortality ratios (SMRs) or standardized incidence ratios (SIRs) from cohort studies and odds ratios (ORs) from case-control studies.

Results: A significantly increased risk of laryngeal cancer (pooled OR = 1.39, 95% confidence interval (95% CI): 1.17-1.67) among workers exposed to silica dust was observed by combining six case-control studies with adjustment for smoking and alcohol consumption. A similarly increased but statistically non-significant risk estimate was observed from cohort studies, with a pooled SMR of 1.38 (95% CI: 0.79-1.96) for silicosis cases; and a pooled SMR of 1.13 (95% CI: 0.82-1.45) and a pooled SIR of 1.50 (95% CI: 0.59-2.42) for workers with silica dust exposure.

Conclusion: This systematic review demonstrated a weak association between silica or silicosis and laryngeal cancer. Owing to the inherent limitations of the original studies, interpretation of the results of this meta-analysis should be cautious.

Publication types

  • Meta-Analysis
  • Review
  • Systematic Review

MeSH terms

  • Air Pollutants, Occupational / adverse effects*
  • Dust*
  • Humans
  • Laryngeal Neoplasms / chemically induced*
  • Laryngeal Neoplasms / complications
  • Occupational Diseases / chemically induced*
  • Occupational Exposure / adverse effects*
  • Odds Ratio
  • Silicon Dioxide / adverse effects*
  • Silicosis / complications


  • Air Pollutants, Occupational
  • Dust
  • Silicon Dioxide