Malignant Pleural Mesothelioma Outcomes in the Era of Combined Platinum and Folate Antimetabolite Chemotherapy

Introduction. Malignant pleural mesothelioma (MPM) is associated with a poor prognosis. Palliative platinum-based chemotherapy may help to improve symptoms and prolong life. Since 2004, the platinum is commonly partnered with a folate antimetabolite. We performed a review investigating if survival had significantly changed before and after the arrival of folate antimetabolites in clinical practice. Methods. All MPM patients from January 1991 to June 2012 were identified. Data collected included age, gender, asbestos exposure, presenting signs/symptoms, performance status, histology, stage, bloodwork, treatment modalities including chemotherapy, and date of death or last follow-up. The primary endpoint was overall survival. Cox models were applied to determine variables associated with survival. Results. There were 245 patients identified. Median overall survival for all patients was 9.4 months. After multivariate analysis, performance status, stage, histology, leucocytosis, and thrombophilia remained independently associated with survival. Among all patients who received chemotherapy, there was no difference in overall survival between the periods before and after folate antimetabolite approval: 14.2 versus 13.2 months (P = 0.35). Specifically receiving combined platinum-based/folate antimetabolite chemotherapy did not improve overall survival compared to all other chemotherapy regimens: 14.1 versus 13.6 months (P = 0.97). Conclusions. In this review, we did not observe an incremental improvement in overall survival after folate antimetabolites became available.