Upfront Bevacizumab and Temozolomide or Fotemustine before Radiotherapy for Patients with Glioblastoma and Severe Neurological Impairment at Diagnosis

Abstract

Unresectable glioblastomas with severe neurological impairment at diagnosis have a poor prognosis. The conventional approach using a temozolomide-based chemoradiotherapy has limited efficiency on patients in the RTOG RPA V–VI classes. The activity of the antiangiogenic monoclonal antibody bevacizumab is well defined in recurrent glioblastoma, despite the fact that its impact on survival is not yet established. We wondered if neoadjuvant bevacizumab, used as upfront treatment in combination with a cytotoxic agent, was tolerable and active on neurological signs in patients with severe alteration of the neurological status due to the tumor being located in functional areas. Eight patients received intravenous bevacizumab, 10 mg/kg every 2 weeks, and either oral temozolomide (150–200 mg/m ²/day for 5 days every 4 weeks) or intravenous fotemustine (80 mg/m ² every 2 weeks). After an average of 5 cycles of bevacizumab, a clinical improvement of neurological functions was recorded in 8/8 patients who could then receive radiotherapy at a conventional dose (60 Gy in 30 fractions) with continuation of bevacizumab and the cytotoxic agent. Four out of the 8 patients benefited from a durable stabilization and experienced an unusually long survival in such a bad situation at diagnosis. In conclusion, neoadjuvant bevacizumab with chemotherapy appears to be feasible and efficient in a category of patients from the RTOG RPA V–VI classes, by allowing the completion of full-dose radiotherapy. A clinical trial is planned to confirm these retrospective observations.