Radiotherapy with and without temozolomide in elderly patients with glioblastoma.

ABSTRACT

BACKGROUND AND PURPOSE: The optimal treatment for elderly patients (age ≥ 70 years) with glioblastoma (GBM) remains controversial. We conducted a retrospective analysis in 43 consecutive elderly patients with glioblastoma who either underwent radiotherapy (RT) or radiotherapy plus concomitant temozolomide (TMZ). PATIENTS AND METHODS: A total of 43 patients (≥ 70 years of age, median age 75.8 years) with newly diagnosed glioblastoma and a Karnofsky performance status (KPS) ≥ 70 were treated with RT alone (median 60 Gy in 2 Gy single fractions) or RT plus TMZ at a dose of 75 mg/m(2) per day. The two groups were well-balanced; univariate (log-rank test) and multivariate Cox proportional hazards analysis were used to identify relevant prognostic factors. RESULTS: The median overall survival (mOS) of the entire patient cohort was 264 days (8.8 months) and the median progression-free survival (PFS) was 192 days (6.4 months). The factors age, sex, previous surgery, KPS, and concomitant use of TMZ had no significant influence on OS/PFS; multivariate analysis was performed to obtain adjusted hazard ratios. TMZ use resulted in a trend toward poorer overall survival when applied concomitantly (314 days compared to 192 days within the TMZ group, p = 0.106). The subgroup analysis revealed that TMZ use resulted in significantly worse survival rates in patients with KPS70 (p = 0.027), but for patients with KPS80 this difference was not detectable. CONCLUSION: TMZ should only be used carefully in elderly patients with unfavorable KPS. In this patient cohort, radiotherapy alone is a reasonable option. Standard RT plus concomitant TMZ may be an advantageous treatment option for elderly patients with newly diagnosed glioblastoma who present with good prognostic factors.