Combined treatment involving peritonectomy procedures, multivisceral resections, and hyperthermic intraperitoneal chemotherapy (HIPEC) has reportedly resulted in survival benefit for peritoneal surface malignancies, including diffuse malignant peritoneal mesothelioma (DMPM). Many unanswered questions remain regarding the surgical options in the management of DMPM. The aim of this case–control study was to assess the impact of the type and extent of parietal peritonectomy on survival and operative outcomes.

Thirty patients with DMPM undergoing selective parietal peritonectomy (SPP) of macroscopically involved regions, and 30 matched patients undergoing routine complete parietal peritonectomy (CPP), regardless of disease distribution, were retrospectively identified from a prospective database.

Groups were comparable for all characteristics, except for a higher proportion of patients treated before July 2003 and undergoing preoperative systemic chemotherapy in the SPP group. Median follow-up was 86.2 months in the SPP group and 50.3 months in the CPP group. Median overall survival was 29.6 months in the SPP group and not reached in the CPP group; 5-year overall survival was 40.0% and 63.9%, respectively (P = 0.0269). At multivariate analysis, CPP versus SPP was recognized as an independent predictor of better prognosis, along with complete cytoreduction, negative lymph nodes, epithelial histology, and lower MIB-1 labelling index. Morbidity and reoperation rates were not different between groups. No operative mortality occurred. In 12 of 24 patients undergoing CPP, pathologic examination detected disease involvement on parietal surfaces with no evident tumor at surgical exploration.

CPP improved survival in patients with DMPM undergoing combined treatment. This information may contribute to standardize surgical options for DMPM and other peritoneal malignancies.