Although
temozolomide (TMZ) replaced nitrosoureas as the standard initial
chemotherapy for
glioblastoma (GBM), no studies have compared TMZ with
nimustine (
ACNU), a nitrosourea agent widely used in central Europe and most Asian regions. One hundred thirty-five patients with GBM who underwent extensive
tumor resection in our institution received both radiation and
chemotherapy as initial treatment, 34 received TMZ and 101
ACNU-based (
ACNU plus
teniposide or
cisplatin)
chemotherapy. Efficacy analysis included overall survival (OS) and progression-free survival (PFS). The following prognostic factors were taken into account: age, performance status, extent of resection, and O(6)-methylguanine-DNA-methyltransferase (MGMT) gene status. The median OS was superior in the TMZ versus the
ACNU group (p = 0.011), although MGMT gene silencing, which is associated with a striking survival benefit from
alkylating agents, was more frequent in the
ACNU group. In multivariate Cox analysis adjusting for the common prognostic factors, TMZ
chemotherapy independently predicted a favorable outcome (p = 0.002 for OS, hazard ratio [HR], 0.45; p = 0.011 for PFS, HR, 0.56). Given that >40 % of patients in
ACNU group did not receive the intensive
chemotherapy cycles because of severe hematological and nonhematological toxicity, we performed a further subanalysis for patients who received at least 4 cycles of
chemotherapy. Although a modest improvement in survival occurred in this
ACNU subgroup, the efficacy was still inferior to that in the TMZ cohort. Our data suggest that the survival benefit of TMZ
therapy is superior to that of an
ACNU-based regimen in patients with extensive
tumor resection, also shows greater tolerability.