Peritoneal mesothelioma is an extremely rare tumor and our sequencing data were in accordance with a previous study in which the authors performed WES on 7 PM finding a low mutational rate and BAP1 as the most altered gene.[25] We also found an insertion in BAP1, potentially associated with a loss-of-function, and a deletion changing the reading frame in SETD2, a gene found altered in malignant pleural mesothelioma.[26] In addition, we detected a novel mutation in the WT1 transactivation domain (NM_000378.4; c.212C>T; p.Ser71Phe). The gene discussed is WT1; the disease is malignant pleural mesothelioma.