Intracranial germ cell tumors (GCT) are a group of relatively uncommon tumors that display histologic, genetic, biochemical, diagnostic, and therapeutic similarities to the more common GCTs that occur outside the central nervous system. Their extra-embryonic origins in the fetal yolk sac account for their numerous similarities, and subsequent migratory paths early in fetal development underlie their ubiquitous primary sites. Intracranial GCTs most commonly arise from the pineal or suprasellar region and their location has traditionally hampered surgical management. For this reason, radiation alone, frequently encompassing a large treatment volume, has constituted the gold standard for treatment. In the last two decades, effective chemotherapy in combination with improved neurosurgical procedures and radiation techniques have resulted in dramatic improvements in survival. However, the morbidity of radiation therapy in children, particularly craniospinal irradiation (CSI), has prompted many investigators to explore approaches that reduce the volume and dose of radiotherapy while preserving high cure rates (Shirato et al. 1997; Choi et al. 1998; Matsutani et al. 1998; Aoyama et al. 2002).