GCT-65. INCIDENCE AND OUTCOME OF INTRACRANIAL MALIGNANT GERM CELL TUMOURS DIAGNOSED IN WESTERN DENMARK IN THE LAST DECADE

INTRODUCTION: Intracranial malignant germ cell tumours (iGCT) are rare brain tumours mainly diagnosed in children and younger adults. MATERIAL AND METHODS: A retrospective analysis was performed by chart review of patients treated for iGCT in the northern and central region of Denmark. Teratoma only patients were not included in the study. RESULTS: 20 patients with iGCT were diagnosed from 2008–2019 in Western Denmark. The cumulative incidence was 1.05 per 100.000. The yearly incidence was 0.1 per 100.000. Mean age at diagnosis was 18 years (range 8–36 years), 17 were males and 3 were females. 13 patients presented with germinoma and 7 patients with non germinomateous germ cell tumours (NGGCT). Three patients had disseminated disease, two with germinoma and one with NGGCT. All patients had received radiotherapy and 18 patients were treated with multidrug chemotherapy including platinum and etoposide before irradiation. Two patients experienced recurrent disease, both non disseminated at diagnosis, one patient with germinoma and one patient with NGGCT. Both received salvage treatment including high dose chemotherapy with stem cell transplantation and reirradiation. Two NGGCT patients died, one patient after development of an anaplastic astrocytoma in the radiation field five years after radiotherapy and one patient after intracranial hemorraghe 18 months after salvage treatment for recurrent disease. Overall survival was 90%, 100% for GCT and 71% for NGGCT. CONCLUSION: The outcome of patients with iGCT in Western Denmark was comparable to the literature. A nationwide study of epidemiology and outcome of iGCT in Denmark is planned.