Concurrent Pemetrexed/Cisplatin With Pleural Intensity Modulated Radiation Therapy for Patients With Unresectable Malignant Pleural Mesothelioma

The purpose of this study is to evaluate the safety of combining chemotherapy at different doses with a specific type of radiation therapy delivered to the entire lining of the lung to find out what effects, if any, it has on people. This radiation technique is called pleural intensity modulated radiation therapy (IMRT). IMRT specifically targets the lining of the lung (pleura) where the cancer is and reduces the risk of damaging the lung itself. When given after chemotherapy, pleural IMRT has demonstrated promising results with respect to keeping mesothelioma under control longer. However, the investigators want to determine if giving pleural IMRT at the same time as chemotherapy is safe. If safe, further studies will be done to see if chemotherapy and pleural IMRT given at the same time keeps the tumor under control for a longer period of time than chemotherapy followed by pleural IMRT.