Peritoneal mesothelioma

Opinion statement

Peritoneal mesothelioma is usually a rapidly fatal primary peritoneal surface malignancy with a median survival time of less than 1 year, mainly because of lack of effective treatment. The incidence is approximately one per 1,000,000; approximately one fifth to one third of all mesotheliomas are peritoneal. Because of its unusual nature, the disease has not been clearly defined in terms of its natural history, diagnosis, or management. Treatment options with intravenous chemotherapy are far from satisfactory. However, because malignant peritoneal mesothelioma usually remains confined to the peritoneal cavity for most of its natural history, regional chemotherapy is an attractive option. From a theoretic perspective, the treatments are most likely to succeed in selected patients with small-volume residual disease after cytoreductive surgery. Advantages of intraperitoneal chemotherapy include greatly enhanced drug concentrations in the peritoneal cavity and decreased systemic toxicity. In designing an intraperitoneal treatment strategy for the management of peritoneal mesothelioma, the limited number of active cytotoxic drugs and the timing of drug delivery pose problems. Prognosis as determined by clinical presentation, the completeness of cytoreduction, and gender (female patients survive longer than male patients) appears to be improved by the use of intraperitoneal chemotherapy. Over the past decade, the management of these patients has evolved similarly to ovarian cancer treatment and now involves cytoreductive surgery, heated intraoperative intraperitoneal chemotherapy with cisplatin and doxorubicin, and early postoperative intraperitoneal paclitaxel. These perioperative treatments are followed by adjuvant intraperitoneal paclitaxel and second-look cytoreduction. Prolonged disease-free survival and reduced adverse symptoms with the current management strategy are documented by a high complete response rate as assessed by a negative second look. This multimodality treatment approach with debulking surgery and intraperitoneal chemotherapy has resulted in a median survival of 50 to 60 months. Peritoneal mesothelioma is an orphan disease that is treatable, with expectations for “potential” cure in a small number of patients diagnosed and treated early with definitive local/regional treatments. A prolonged high quality of life is possible in the majority of patients.