In 2007, the United States’ National Cancer Institute reported that over 126,000 individuals in the United States alone were aected by primary brain or other central nervous system (CNS) cancers [Altekruse et al., 2010]. In addition to these numbers, metastatic brain cancer aects a signicant percentage of those suering from other primary cancers. Lung and breast cancer patients are particularly prone to developing brain metastases, with one study nding that as many as 19% of lung cancer patients will be diagnosed with brain metastases, and as many as 5% of breast cancer patients [Barnholtz-Sloan et al., 2004]. Old autopsy data from patients with breast carcinoma suggest the incidence may be higher, with as many as 30% developing CNS metastases [Tsukada et al., 1983]. Survival rates are poor once brain metastases develop, with a reported median survival of just seven months in patients with good prognosis [Gaspar et al, 1997]. orough reviews on both primary [Behin et al., 2003] and metastatic [Kamar and Posner, 2010] brain cancer exist that describe diagnosis and classication of the various tumor types.