Dragani TA, et al. - Given that asbestos exposure is the main etiology of malignant mesothelioma, researchers investigated if the intensity of exposure modulates the development of this disease via analyzing 594 malignant mesothelioma patients for whom count data on asbestos bodies and fibers (per gram of wet lung tissue) were available. In heavily exposed subjects, tumors become clinically apparent at a younger age suggesting the involvement of asbestos not only in the of malignant mesothelioma tumor initiation but, somehow, also in the progression of the disease.