Sex difference in diffuse malignant peritoneal mesothelioma

Background: Diffuse malignant peritoneal mesothelioma (DMPM) is rare and in the past has proved an invariably fatal disease. Female patients have been reported to have an improved survival outcome for reasons that are not understood. Methods: The survival of 34 men and 28 women who underwent cytoreduction and perioperative intraperitoneal chemotherapy for DMPM was compared. Twenty-five clinicopathological variables were subjected to univariate analysis. Results: The women had a 5-year survival rate of 63 per cent and median survival was not reached. The men had a 5-year survival rate of 42 per cent, with a median survival of 32 months (P = 0.045). Women had undergone more extensive previous surgery and had less extensive peritoneal involvement at the time of cytoreduction. Tumours in women more frequently showed a small nuclear size (30 mu m or less) and the chromatin pattern was more often granular than clear. Conclusion: Women with DMPNI had better survival. This observation may be related to the favourable clinical and histopathologicol features associated with women.