DDEL-07. EFFICACY OF TEMOZOLOMIDE IN MEDULLOBLASTOMA PATIENTS: REVIEW OF SERIES OF TWO ADULT PATIENTS WITH RECENT UPDATES IN LITERATURE

Abstract Medulloblastoma is a primary malignant CNS tumor commonly seen in children and rarely in adults (20% vs 1% of all primary brain tumors). Maximal safe resection and craniospinal irradiation followed by adjuvant chemotherapy have proven to be an effective treatment in children. Due to insufficient data available in adult patients, it is also the usual approach in them despite unclear long-term outcomes. Standard chemotherapeutic regimens consisting of vincristine, cisplatin, and lomustine are known to cause greater toxicity in adults making adequate dose titration a challenge. Temozolomide is a second-generation cytotoxic alkylating agent with favorable CNS penetration. It is a potential alternative that has yielded superior results in treating gliomas and preventing recurrence along with minimal toxicity. We discuss a series of two adult medulloblastoma cases which were given 24 cycles of Temozolomide monotherapy over two years following surgical resection and craniospinal irradiation. Serial MRIs did not report any signs of recurrence rendering one case cancer-free for seventeen years and the other for ten. Minimal toxicity in the form of nausea, vomiting, headache, and reversible, temporary pancytopenia was seen in contrast to other agents. Improved survival with minimal toxicity was demonstrated in both cases proving the efficacy of Temozolomide as adjuvant chemotherapy for adult Medulloblastoma. While a regimen of Temozolomide is recommended for recurrent Medulloblastoma, there is no optimal regimen available for initially diagnosed, localized tumors, especially in adults. Multi-institutional clinical trials are required to study its role as a monotherapy during an early yet critical phase of management.