RecruitingPhase 2Drug trialA Study of Additional Chemotherapy After Surgery for People With Malignant Peritoneal MesotheliomaThe purpose of this study is to find out whether intraperitoneal or intravenous chemotherapy given after cytoreductive surgery and HIPEC are effective treatments for people with malignant peritoneal mesothelioma. Outcomes will be compared by observing intraperitoneal versus intravenous treatments to analyze if one is better than the other.