Background: Cancer of the larynx is one of the most common in men after age 50, reaches over the head and neck region, representing 25% of malignant tumors that affect this area and 2% of all malignancies. Approximately two thirds of these tumors arise in the true vocal cord and 1/3 is located above the vocal cords. The relationship between HPV and the diseases of the upper airways has been known for almost a century, but only in the last three decades has its potential oncogenic activity as recognized in the literature. HPV types similar to those found in the cervix were also observed in cancer of the larynx, tongue and oropharynx. Objectives: To assess the frequency of HPV in laryngeal cancer samples, identify the genotypes of HPV in laryngeal cancer sample; establish the relationship between laryngeal cancer and HPV as a risk factor. Methods: Systematic review of clinical trials in which descriptors and synonyms for Laryngeal Neoplasms and Papillomavirus Infections were used in the following electronic databases by March 2012: CENTRAL, MEDLINE (PUBMED), LILACS and SciELO. Three reviewers selected, assessed methodological quality and extracted data from relevant studies. Results: Individual Estimates combined in a meta-analysis resulted in a statistically significant difference of HPV among cases compared to controls, most likely among cases (OR 4.26, 95% CI of 2.05 to 8:87, P = 0.004). Statistical analysis suggests substantial heterogeneity (I2) between studies (I2> 50%, P <0.1), which can be explained by the type of control used. The viral type more frequent among cases was between 16 and HPV controls viral types were HPV-6 and HPV-16 and -18. Conclusions: The results of this meta-analysis support the hypothesis of the involvement of HPV in laryngeal cancer, suggesting that HPV is a risk factor of differentiation depends on the other factors and the method of identification of viral DNA.
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