Abstract
BACKGROUND
Temozolomide (TMZ) is the cornerstone for glioblastoma (GBM) treatment. A significant proportion of patients develops hematologic toxicities with limited investigations on outcomes and risk factors for their development.
METHODS
Our study combines data from the two largest group trials, RTOG 0525 and RTOG 0825, to analyze serious hematologic adverse events (HAE) associated with TMZ therapy for GBM. We analyzed frequency and outcomes of HAE during chemoradiation.
RESULTS
1154 patients were evaluated with a median age of 57 years. Over 79% of patients developed HAE during the entire course of GBM treatment. During chemoradiation the most common HAE during chemoradiation was lymphopenia (41.5%), followed by thrombocytopenia (39.0%), and anemia (35.3%). Of these, 34.1% were severe (Grade 3 or 4) and 65.9% were mild (grade 1 or 2). During maintenance the most common HAE was leukopenia (50.7%), followed by neutropenia (50.4%), and lymphopenia (45.3%). MGMT methylation was not associated with HAEs. A history of HAEs during chemoradiation was a protective factor for developing HAEs during maintenance. MGMT methylated and age younger than 50 were protective factors for mortality. Patients that presented HAEs anytime during treatment had a longer overall survival and progression free survival. There was no significant difference in survival between mild or severe HAEs.
CONCLUSION
HAE are common during chemoradiation with TMZ for GBM, but are more commonly grade 1 or 2 per CTCAE. HAE during GBM treatment is associated with decreased progression free survival and overall survival.