Identified clusters of malignant mesothelioma cases in South & Islands, Italy, ReNaM, 1993–2008. Smoothed relative risk (RR) estimates of incident cases of mesothelioma (all sites) recorded by the Italian registry of malignant mesothelioma (ReNaM) in the 1993–2008 period are mapped based on municipality of residence. No incidence data are available for Molise, Calabria and Sardinia (not shown). Only municipalities with RR higher than 1 are shown in the figure and color-coded. Cluster labels refer to the municipality with the highest number of cases.