Induction chemotherapy followed by reduced-volume radiation therapy for newly diagnosed central nervous system germinoma

Abstract

Object. Although curative, radiation, which is conventionally administered for germinomas, causes significant neurological sequelae. This study aimed at reducing the volume and dose of radiation to a localized level of 24 Gy by pretreating the patient with chemotherapy. Methods. Seventeen patients were divided into two risk groups based on serological findings and the extent of tumor. They were treated with chemotherapy prior to receiving localized radiation therapy. Six patients with solitary pure germinomas were treated with three or four cycles of cisplatin and etoposide (EP regimen) followed by 24-Gy local radiation therapy. Eleven patients with human chorionic gonadotropin (HCG)—secreting, multifocal, or disseminated germinomas received four to five cycles of ifosfamide, cisplatin, and etoposide (ICE regimen) followed by 24-Gy local radiation therapy. Craniospinal ports were used only in three cases of germinomas with dissemination. Gross-total resection was performed in three patients. Fourteen patients were able to be evaluated for their responses to chemotherapy. All patients achieved a complete response within three cycles. At a median follow-up duration of 24 months, 16 patients (94%) were alive without recurrence. One patient with an HCG-secreting germinoma experienced recurrence 38 months after surgery. That patient underwent successful salvage therapy using the same protocol. Thus, all 17 patients became free of disease with a 70 to 100% Karnofsky Performance Scale status. Toxicities associated with this study's chemotherapy regimen were mostly transient. No patient showed neurological or endocrinological deterioration during the follow-up period. Conclusions. The EP and ICE regimens were highly effective in treating the central nervous system germinomas and permitted dose and volume reduction of the radiotherapy. Localized 24-Gy irradiation was sufficient for disease control.