High-Risk Peritoneal Mesothelioma: Does Metronomic Chemotherapy Have a Role?

To evaluate the feasibility, tolerance, and efficacy of OMCT (oral metronomic chemotherapy) after CRS + HIPEC for peritoneal mesothelioma in patients with poor prognostic factors: PCI > 20, incomplete CRS, poor performance status, or progression on systemic chemotherapy.

A retrospective analysis of patients undergoing CRS + HIPEC for peritoneal mesothelioma and receiving OMCT for poor risk factors.

Sixteen patients underwent CRS + HIPEC between 2013 and 2017. The median PCI was 31.5. Complete cytoreduction (CC-0/1) was obtained in 8 patients (50%). All 16 received HIPEC except one patient with baseline renal dysfunction.Thirteen patients had PCI > 20 where only 5 had CC-0/1. Of 8 suboptimal cytoreduction (CC-2/3), 7 received OMCT (6 for progression on chemotherapy and one for mixed histology). Three patients had PCI < 20 and all had CC-0/1 clearance. Only one received OMCT for progression on adjuvant chemotherapy. Patients receiving OMCT for progression on adjuvant chemotherapy (ACT) were in poor PS.The median follow-up was 13.4 months. Five are alive with the disease (three are on OMCT). Six are alive without disease (2 are on OMCT). The mean OS was 24.3 months and the mean DFS was 18 months. Outcomes were similar between CC-0/1 and CC-2/3 groups, OMCT vs no OMCT groups.All patients receiving OMCT for progression on neoadjuvant chemotherapy had better survival (alive at 12, 20, 32, 36 months) compared to those receiving OMCT for progression on the ACT (p = 0.012).

OMCT is a good alternative in high-volume peritoneal mesothelioma with incomplete cytoreduction and progression on chemotherapy. OMCT may improve outcomes in these scenarios when started early.