Retrospective analysis of effects of radiotherapy with concomitant and adjuvant Temozolomide versus radiotherapy alone in patients with Glioblastoma

Glioblastoma remains one of the greatest challenges in oncology today. Although radiotherapy improves the outcomes after surgery, overall survival is poor and it needs new treatment approaches to provide better long term survival. In this regard, several drugs have been studied including nitroureas based chemotherapy, however, temozolomid as an alkylating agent is an promising agent for GB patients.In this study, we retrospectively investigated our GB patients and we compared the effects of radiotherapy with concomitant and adjuvant temozolomide versus radiotherapy alone on survival. A total of 140 patients was recruited and 80 were on temozolomide and 60 were on radiotherapy alone groups. Both groups were same for demographic features (age, gender) and prognostic indexes including ECOG and RPA. Also, the type of surgery was similar in both groups.In survival analyses, it was shown that median overall survival was 17 months in temozolomide group while it is 15 months in radiotherapy alone group (p<0.002). The average time of overall survival was also significantly better in temozolomide group (19.9 ± 1.5 vs 14.8 ± 0.7 months). Moreover, progression free survival was 14.4 months in temozolomide group and it was 9 months in radiotherapy alone group (p<0.0001). The average time of progression free survival was 17.0 ± 1.7 months in temozolomide group and it was 10.0 ± 0.7 months in radiotherapy alone group. When prognostic factors were evaluated, only ECOG score was independent varibale predicting overall and progression free survival in multivariate analysis.In our study, we found that concomitant and adjuvant temozolomide provide better overall survival and progression free survival in GB patients. Further studies are needed to find prognostic factors.