EPID-36. CLINICAL FEATURES OF 614 PRIMARY INTRACRANIAL GERM CELL TUMORS: AN 15-YEAR EXPERIENCE OF A SINGLE CENTER IN CHINA

Abstract Incidence of primary intracranial germ cell tumors (ICGCT) in Asian countries is higher than Western countries. This study aims to describe the characteristics of ICGCT patients in China. Data on all patients with ICGCT who were seen at the Department of Neuro-oncology, Sanbo Brain Hospital, Capital Medical University from 2007 to 2022 were collected retrospectively. Patient demographics, disease characteristics and treatment outcomes were analyzed. A total of 614 patients were identified, with 309 germinomas and 305 non-germinomatous germ cell tumors (NGGCT). The median age at diagnosis was 12.8 years. The male-female ratio is 2.4 to 1. The primary disease sites were mainly pineal gland and suprasellar region. Adults (age≥23) were more likely to develop germinomas (65.3%). 78% patients received radiotherapy after initial diagnosis. In M0 patients, whole brain radiotherapy was the most common approach, while in M+ was craniospinal radiotherapy. Whole ventricle radiotherapy was uncommon (4%). The most common chemotherapy regimen for germinoma was a combination of bleomycin, cisplatin and etoposide/tenipside; while for the NGGCT was ifosfamide combined with carboplatin/cisplatin and etoposide. For germinoma, the median recurrence-free survival (RFS) and overall survival (OS) were 150.3 months and 222 months; the 10 year RFS and OS were 58.2% and 85.1%, respectively. For NGGCT, the median RFS and OS were 80.4 months and 166.7 months; the 10 year RFS and OS were 46.9% and 60.5%. At relapse, four (0.65%) developed secondary malignancies. Seven (1.14%) developed extracranial dissemination. Chemotherapy and radiotherapy could improve the RFS and OS. Higher radiation dose was associated with better prognosis. The prognosis of focal radiotherapy alone was poor. M0 germinoma treated with focal radiotherapy alone were more likely relapse. This study suggested that treatment outcomes of our ICGCT patients are comparable with those in Western centers. Adjuvant chemotherapy and whole brain/craniospinal radiotherapy are pivotal treatment.