Efficacy of temozolomide as adjuvant chemotherapy after postsurgical radiotherapy alone for glioblastomas

The aim of this study was to assess the efficacy of adjuvant TMZ chemotherapy for newly diagnosed GBM patients who were treated with surgery followed by radiotherapy alone.

Between January 2003 and April 2005, 59 consecutive GBM patients underwent radiation therapy after surgical resection and subsequently received TMZ chemotherapy. For the comparative analysis, we selected 60 clinically matched GBM patients who underwent radiotherapy followed by nitrosourea-based chemotherapy (NUBC), at the same institution between June 1995 and April 2005. The study cohort was divided into two groups, those with adjuvant TMZ treatment and with NUBC.

59 patients with adjuvant TMZ treatment were assigned to the treatment group and 60 patients with NUBC to the control group. The median overall survival for the treatment group was 18.2 months (95% CI, 11.7-24.7 months), compared with the survival of 14.5 months (95% CI, 11.2-17.7 months) for the control group (p=0.019). The progression-free survival for the treatment group was 5.6 months (95% CI, 4.4-6.7 months), while the control group showed progression-free survival of 3.3 months (95% CT, 3.2-6.0 months) (p=0.030). Uni- and multivariate analysis revealed that extent of surgical resection, age > or =55 years and postoperative KPS were significantly associated with survival.

Adjuvant TMZ chemotherapy provided a clinically relevant benefit of survival, as compared with NUBC. Thus, we suggest that adjuvant TMZ chemotherapy may be effective even for patients who did not receive concomitant chemoradiotherapy for GBM.