NCOG-43. THE APPLICATION OF INDUCTION CHEMOTHERAPY COMBINED WITH RADIOTHERAPY IN YOUNG ADULTS WITH CNS GERM CELL TUMORS

Abstract BACKGROUND Central nervous system (CNS) germ cell tumors are rare brain neoplasms, accounting for approximately 0.3-0.5% of all CNS tumors. A combination of radiotherapy and chemotherapy is the standard of care (SOC) in pediatric patients. However, there is no SOC for young adult or adult patients. This study evaluates a regimen of induction chemotherapy followed by radiation in treating young adults with CNS germ cell tumors. METHOD Nine young adult patients diagnosed with pure CNS germinomas were identified in our institution. They underwent a treatment regimen of induction chemotherapies that were planned for four cycles and consisted of bleomycin (three doses per cycle), cisplatin (five doses per cycle) and etoposide (five doses per cycle) followed with whole brain and/or ventricular radiotherapy. The patients’ overall survival (OS), neurological function (including cognition), and adverse events (AE) were analyzed. RESULT Among the nine patients (seven males and two females), the median age is 20 years (range: 17-33 years). They received bleomycin, cisplatin and etoposide (median: two cycles, range: 1-4), and subsequent radiotherapy with plans based on tumor location by radiation oncologists, with a median radiotherapy dose of 45 Gy (range: 36-50.4). Seven patients had a complete response after chemotherapy. The median OS is 53 months (range: 39-121). There is no identifiable cognitive impairment by neurological exam. All patients experienced at least one, reversible, grade 3 AE of myelosuppression. All patients return to their normal baseline including employment. Results of neuropsychological evaluation and all AEs will be presented at the conference. CONCLUSION Induction chemotherapy followed by radiotherapy is potentially safe and effective with manageable and reversible side effects from chemotherapy without cognitive and functional impairment in the nine young adult patients with CNS germ cell tumors. A prospective study of this approach in a clinical trial setting is warranted.