Limited impact of prognostic factors in patients with recurrent glioblastoma multiforme treated with a bevacizumab-based regimen.

Bevacizumab has demonstrated activity in patients with recurrent glioblastoma. However, the impact of prognostic factors associated with recurrent glioblastoma treated with cytotoxic agents has not been determined in patients treated with bevacizumab. To analyze the prognostic factors and clinical benefits of bevacizumab and irinotecan treatment in patients with recurrent glioblastoma. This monocentric study retrospectively analyzed all patients with recurrent glioblastoma who were treated with at least one cycle of bevacizumab and irinotecan at our institution from April 2007 to May 2010. Multivariate analysis was used to analyze prognostic factors for overall survival (OS) from the initiation of bevacizumab administration. Among the 100 patients that were identified (M/F: 65/35), the median age was 57.9 years (range: 18-76). Karnofsky Performance Status (KPS) was <70 in 44 patients and ≥ 70 in 56 patients; 83 % of the patients were on steroids. The median tumor area was 2012 mm². The median progression free survival was 3.9 months (CI 95 %: 3.4-4.3). The median OS was 6.5 months (CI 95 %: 5.6-7.4). Multivariate analysis revealed that OS was affected by KPS (p = 0.024), but not by gender, age, steroid treatment, number of previous lines of treatment, tumor size, or time from initial diagnosis. KPS was improved in 30 patients, including 14/44 patients with an initial KPS <70. The median duration of maintained functional independence (KPS ≥ 70) was 3.75 months (CI 95 %: 2.9-4.6). The median OS from initial diagnosis was 18.9 months (CI 95 %: 17.5-20.3). In patients with recurrent glioblastoma treated with bevacizumab, KPS was revealed as the only factor to impact OS. The clinical benefits associated with this regimen appear valuable. A positive impact of bevacizumab administration on OS of patients with glioblastoma multiforme is suggested.