Pemetrexed Plus Gemcitabine or Carboplatin for Patients With Advanced Malignant Pleural Mesothelioma

OBJECTIVES: Primary * Estimate the response rates in patients with advanced malignant mesothelioma of the pleura treated with pemetrexed disodium combined with either gemcitabine or carboplatin. Secondary * Assess the toxic effects of these regimens in these patients. * Estimate survival time in patients treated with these regimens. * Correlate smoking status with outcome in patients treated with these regimens. OUTLINE: This is a randomized, multicenter study. Patients are randomized to 1 of 2 treatment arms. While randomized, the study is not a comparative study. Rather, outcomes on each arm will be compared to a historical control rate from previous studies. Randomization allows simultaneous testing of two experimental arms. * Arm I: Patients receive intravenous (IV) pemetrexed disodium over 10 minutes and carboplatin IV over 30 minutes on day 1. * Arm II: Patients receive pemetrexed disodium as in arm I and gemcitabine IV over 30 minutes on days 1 and 8. In both arms, treatment repeats every 21 days for up to 6 courses in the absence of disease progression or unacceptable toxicity. Beginning approximately 5-10 days before the start of chemotherapy and continuing until approximately 3 weeks after completion of chemotherapy, all patients receive oral folic acid once daily and cyanocobalamin (vitamin B12) intramuscularly every 9 weeks. Patients are followed every 3 months for 2 years and then every 6 months for 1 year. PROJECTED ACCRUAL: A total of 32-60 patients (16-30 per treatment arm) will be accrued for this study within 12.8-27.0 months.