Central Nervous System Nongerminomatous Germ Cell Tumors

Abstract

Intracranial nongerminomatous germ cell tumors (NGGCT) encompasses a heterogeneous group of germ cell tumors of various histology which occur in the brain. Various criteria for prognostic categorization have been used in different parts of the world with varying treatment strategies. Systemic chemotherapy is an essential part of the multimodal treatment of NGGCT. Survival rate of patients with NGGCT is 60–70% with use of combined chemoradiotherapy. From the published literature, craniospinal radiotherapy (CSI) combined with cisplatin-based chemotherapy with or without second-look surgery tends to provide the best treatment outcome for NGGCT. Intracranial NGGCT requires high radiation dose >50 Gy to the primary site, however, the optimal volume of radiotherapy is still debatable. Whole ventricular irradiation is currently being adopted for localized intracranial NGGCT to minimize late neurocognitive toxicity. A Children Oncology Group study is currently underway to test whether the dose and volume of radiotherapy can be adapted according to the tumor response to chemotherapy. The role of surgery in treatment of NGGCT is both diagnostic and therapeutic. In Europe and North America, delayed surgery for persistent disease after chemotherapy is preferred, while in Japan, more aggressive and upfront resection is advocated for better therapeutic design. Use of intensity-modulated radiotherapy (IMRT) or proton beam therapy (PBT) is expected to translate to an improved neurocognitive outcome after treatment.