Whole brain radiotherapy with concurrent temozolomide in multifocal and/or multicentric newly diagnosed glioblastoma.

The standard medical care of glioblastoma (GBM) patients with good performance status is based on focal brain radiotherapy (40-60 Gy) with concurrent temozolomide (TMZ) followed by adjuvant TMZ. Newly diagnosed multifocal and/or multicentric GBM (M/M GBM) cases are usually treated with TMZ alone: whole brain chemoradiotherapy (CRT) is avoided for safety reasons. To our knowledge, no study has investigated the safety and efficacy of whole-brain radiotherapy (WBRT) with concurrent TMZ in M/M GBM patients. This retrospective study sought to assess the role of WBRT associated with concurrent TMZ followed by TMZ alone in this population. Eleven patients with pathologically proven M/M GBM (≥3 lobes) were treated with WBRT between April 2009 and September 2017. The median age was 50 years [34-74]. The median dose of radiotherapy was 45 Gy at 1.8 Gy per fraction over 37 days [29-41], with concurrent daily TMZ at the dose of 75 mg/m2. This treatment was followed by adjuvant monthly TMZ (150 mg/m2-D1-D5). All pathology slides and radiology images were reviewed. The median overall and progression-free survival times for all patients were 10 months [4-25] and 5 months [3-21], respectively. There was no grade 3-4 toxicity due to radiotherapy. One patient stopped the TMZ during the radiochemotherapy period and 9 patients received adjuvant TMZ with a median number of 5 cycles [2-8]. Our study supports the safety and the efficacy of WBRT with TMZ in newly diagnosed M/M GBM. Larger prospective studies are needed to support our results.