++
Malignant peritoneal mesothelioma (MPM) is a rare but highly lethal cancer that arises from the serosal membranes of the abdominal cavity. MPM represents about 15 to 20 percent of all malignant mesothelioma diagnoses which translates into approximately 350 to 450 new cases in the United States annually. Patients with MPM almost always succumb to disease progression within the abdominal cavity. There is a strong etiologic association with asbestos exposure although the link has not been as firmly established as in the pleural variant; in almost 40% of individuals with MPM no definite exposure to asbestos can be established. Because of its rarity, progress in the understanding of its molecular biology and advances in the development of more efficacious systemic treatments have been very limited. The disease afflicts gender equally but women and younger patients tend to have a better outcome. Systemic chemotherapy using a combination of cisplatin and pemetrexed has limited efficacy in controlling the disease long-term while surgical cytoreduction (CRS or cytoreduction surgery) with hyperthermic intraperitoneal chemotherapy (HIPEC) has become the accepted initial therapeutic intervention in appropriately selected patients with this disease.
+++
HISTORICAL PERSPECTIVES
++
The first description of a diffuse primary malignant process of the peritoneal serosa was made in a publication in 1908.1 In the report, a 32-year-old male miller with diffuse abdominal pain and ascites was noted to have an extensive and diffuse intraperitoneal neoplastic process that was not amenable to resection at surgical exploration. He was treated with palliative interventions and succumbed to disease 1 year later. Fifty years later, a literature review of 13 pathologically confirmed cases of what was first termed malignant peritoneal mesothelioma or MPM established this disease as a distinct pathological entity.2 Subsequently, an increased number of documented cases were reported in the medical literature and an understanding of the risk factors and clinical features of the condition began to emerge. Moertel3 published a comprehensive review of the subject in 1972 and in 1983 Antman et al4 at the Dana Farber Cancer Center published the first report detailing results of an integrated treatment strategy using a combination of operative resection, whole abdominal radiation, and systemic chemotherapy for patients with MPM. In that study, 18 previously untreated patients with MPM received a doxorubicin-containing regimen that was associated with substantial toxicity. Fourteen had measurable or evaluable disease and of these 14 patients, 6 (43%) had a measurable response. The median survival in the six responding patients was 22 months, while survival for the remaining eight patients who had stable or progressive disease was 5 months. Despite the subsequent development of systemic chemotherapy regimens consisting of pemetrexed and cisplatin or gemcitabine, MPM is still considered a chemotherapy-resistant cancer; overall response rates using these regimens are about 30% and median overall survivals (OSs) are 13 to 27 months.5,6 A single-arm phase II study of tremelimumab (anti-CTLA) in mesothelioma patients resulted in an ...