Temozolomide use in adult patients with gliosarcoma: an evolving clinical practice

The purpose of this study is to determine the factors that impact overall survival (OS) in adult patients with gliosarcoma in the modern era treated at a single institution compared with a cohort from the SEER registry. A total of 46 adult patients with pathologically confirmed gliosarcoma at MD Anderson Cancer Center from 2000 to 2010 were retrospectively analyzed. Demographic and treatment were obtained. For comparison, a total of 218 patients with gliosarcoma in the SEER database from 1991 to 2008 were analyzed. Survival analysis was conducted using the Kaplan-Meier log rank test. At MD Anderson, the overall incidence of gliosarcoma over the specified time interval was 1.5 %. Gliosarcoma was more common in males (n = 31, 67.4 %) with a median age of 56 years (range 24-92 years). Median survival in all patients was 12.5 months. A total of 17 patients (37 %) received temozolomide (TMZ) concurrently with RT and adjuvantly, with a 24 month OS of 20.0 %, compared with 10.2 % among those not treated with this regimen (p = 0.68). In contrast, the 2 year OS rate in the SEER database was 24.2 % during 2006-2008, compared to 12.1 % among those diagnosed in 2000-2003 (p = 0.03), presumably related to the widespread adoption of the chemoradiation regimen. Patients with gliosarcoma treated with TMZ at a single institution improved OS although this finding did not reach statistical significance. Patients diagnosed in the TMZ era in the SEER database display an improved OS, although the explanation for this finding requires further elucidation.