Brain tumor
Glioblastoma multiforme (GBM) is the most aggressive (grade IV) and most common form of a malignant brain tumor. Even when aggressive multimodality therapy consisting of radiotherapy, chemotherapy, and surgical excision is used, median survival is only 12–17 months. Standard therapy for glioblastoma multiforme consists of maximal surgical resection of the tumor, followed by radiotherapy between two and four weeks after the surgical procedure to remove the cancer, then by chemotherapy, such as temozolomide. Most patients with glioblastoma take a corticosteroid, typically dexamethasone, during their illness to relieve symptoms. Experimental treatments include targeted therapy, gamma knife radiosurgery, boron neutron capture therapy and gene therapy.
Mesothelioma
As an environmentally triggered malignancy, mesothelioma tumors have been found to be polyclonal in origin, by performing a X-inactivation based assay on epitheloid and biphasic tumors obtained from female patients. These results suggest that an environmental factor, most likely asbestos exposure, may damage and transform a group of cells in the tissue, resulting in a population of tumor cells that are, albeit only slightly, genetically different.