At least 10% of glioblastoma relapses occur at distant and even contralateral locations. This disseminated growth limits surgical intervention and contributes to neurological morbidity. Preclinical data pointed towards a role for temozolomide in reducing radiotherapy-induced gliomas cell invasiveness. Our objective was to develop and validate a new analysis tool of magnetic resonance imaging (MRI) data to examine the clinical recurrence pattern of glioblastomas. MRIcro software was used to map location and extent of initial preoperative and recurrent tumours on MRI of 63 patients of the EORTC 26981/22981/NCIC CE.3 study into the same stereotaxic space. This allowed us to examine changes of site and distance between the initial and the recurrent tumour on the group level. Thirty of the 63 patients were treated using radiotherapy while the other patients completed a radiotherapy-plus-temozolomide treatment. Baseline characteristics (median age, Karnofsky performance score) and outcome data (progression-free survival, overall survival) of the patients included in this analysis resemble those of the general study cohort. The patient groups did not differ in the promotor methylation status of methyl-guanyl-methly-transferase (MGMT). Overall frequency of distant recurrences was 20%. Analysis of recurrence pattern revealed no difference in the size of the recurrent tumour nor a differential effect on the distance of the recurrences from the preoperative tumour location between the groups. The data show the feasibility of group-wise recurrence pattern analysis. An effect of temozolomide treatment on the recurrence pattern in the EORTC 26981/22981/NCIC CE.3 study could not be demonstrated.