Surgery in the management of primary intracranial germ cell tumors

Surgery plays an important part in the overall management of primary central nervous system (CNS) germ cell tumors. While the general surgical objectives in patients with these neoplasms are similar to those with other types of CNS tumors, to obtain an accurate histopathologic diagnosis and to contribute towards improving patient survival the unique features of germ cell tumors have necessitated novel treatment strategies. Pure germinomas are exquisitely radiosensitive, and prior studies have shown no survival benefit from radical resection of such lesions. However, a significant proportion of CNS GCTs contain admixtures of nongerminomatous GCT (NGGCT) elements and are less responsive to aggressive chemotherapy and irradiation. Biopsy of these malignant GCTs carries the risk of histologic sampling error. Nevertheless, a proportion of NGGCTs produce tumor markers detectable in serum or CSF and may be accurately diagnosed without surgical intervention. Although the role of radical surgical resection has not been definitively demonstrated in the literature, recent data from an international cooperative trial suggest a survival benefit from radical resection of localized NGGCTs. Lastly, increasing experience has supported the role of delayed resective ("second-look") surgery for patients with negative tumor markers but residual radiographic abnormalities after initial chemotherapy. Resection of such lesions has typically yielded necrosis or teratoma, which may be cured by surgical resection, and obviated the need for additional chemotherapy or irradiation.