Mesothelioma deserves particular attention for various reasons: 1) a dramatic increase in the incidence of this tumor has been observed in various countries; 2) diagnosis is not rarely problematic; 3) asbestos-related mesothelioma represents a nearly unique model in human cancerogenesis. Latency periods (defined as intervals between first exposure to asbestos and death) differ from one occupational category to another. These differences seem to depend not only on the intensity of the exposure, but also on other unidentified factors. The study of the mechanisms influencing the length of latency periods could open a way in preventing mesothelioma.