In this cohort of pleural mesothelioma, 45% of sample harboured copy-number deletions, 1.3% had variants and 1.6% had rearrangements in CDKN2A. Compared to pleural mesothelioma, deletions in CDKN2A/B were significantly less frequent in peritoneal mesothelioma. This evidence concerns the gene CDKN2A and peritoneal mesothelioma.