Carboplatin combined with carmustine and etoposide in the treatment of glioblastoma

Phase III study comparing three cycles of infusional carmustine and cisplatin followed by radiation therapy with radiation therapy and concurrent carmustine in patients with newly diagnosed supratentorial glioblastoma multiforme: Eastern Cooperative Oncology Group Trial 2394

PURPOSE

This phase III Eastern Cooperative Oncology Group-Southwest Oncology Group intergroup study was conducted to determine whether three 72-hour infusions of carmustine (BiCNU) and cisplatin administered monthly before external-beam radiotherapy would improve the survival of patients with newly diagnosed glioblastoma multiforme. The control arm consisted of radiation with standard adjuvant BiCNU.

PATIENTS AND METHODS

A total of 223 patients were accrued from 1996 to 1999. Of these, 219 patients were eligible; 109 were randomly assigned to the experimental arm, and 110 were randomly assigned to the control arm. Randomization was stratified by age, performance status, and extent of resection.

RESULTS

The median age of the patients was 55 years; 55% were male, 93% were white, 26% had a biopsy only, and 84% were ambulatory. Treatment arms were well balanced with respect to baseline characteristics. Median follow-up time of the 15 patients still alive at the time of analysis was 3.3 years (range, 2 to 5 years). Median survival times for the standard and experimental arms were 11.2 and 11.0 months (P =.33, two-sided log-rank test), and survival at 1 year was 45% versus 44%, respectively. Fifty-six percent of patients received all three cycles of BiCNU/cisplatin, 12% received two cycles, and 31% received only one cycle. Toxicity was primarily hematologic and was more common in the experimental arm (P <.01).

CONCLUSION

This study demonstrates that 72-hour infusions of BiCNU and cisplatin followed by radiation do not improve median survival, survival at 1 year, or time to progression. Furthermore, this treatment requires more time in the hospital and is associated with more serious toxicities than standard therapy.

O6-methylguanine-DNA methyltranspherase gene expression in gliomas by means of real-time quantitative RT-PCR and clinical response to nitrosoureas

O(6)-methylguanine-DNA methyltransferase (MGMT) mRNA expressions were examined in 100 neuroepithelial tumors by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) using SYBR Green I. The mean relative quantitation value of MGMTmRNA normalized to the level of beta2-microglobulin for 100 tumors was 5.3 +/- 11.2. The mean value of 41 glioblastomas was significantly higher than that for the other 59 tumors (p = 0.0008 by Student's t-test). In contrast, the means of 19 low-grade gliomas and 12 medulloblastomas were significantly lower than that of other tumors (p = 0.0282 and p = 0.0456 by Student's t-test). Among the 55 retrospective patients who had been treated with 1-(4-amino-2-methyl-5-pyrimidynyl)methyl-3-(2-chloroethyl)- 3-nitrosourea hydrochloride (ACNU), the value was a significant independent predictor of the effect of initial therapy with ACNU (p = 0.0007 by Mann-Whitney U-test) and the survival period (p = 0.0175 by Wald test). The value >or=1 was the most significant factor in predicting the initial effect of treatment by multi-variant regression analysis (p < 0.0001). These results suggest that our individual adjuvant therapy based on MGMTmRNA expression may be improved by the application of real-time quantitative RT-PCR.

Preliminary individual adjuvant therapy for gliomas based on the results of molecular biological analyses for drug-resistance genes

New adjuvant therapy individualized by the results of reverse transcription-polymerase chain reaction (RT-PCR) for drug-resistance genes has been used to treat malignant gliomas. Protocol studies for malignant gliomas were not so encouraging in their therapeutic results because of heterogeneity and the various drug-sensitivities of the tumors. Individualization of glioma therapy is recommended. Drug-resistance genes messenger ribonucleic acid (mRNA) expressions were investigated in drug-resistant human glioma cell lines derived from U87MG and 46 frozen samples of retrospectively examined neuroepithelial tumors (12 low grade neuroepithelial tumors, 16 Grade III gliomas, 11 glioblastomas, and 7 other malignant neuroepithelial tumors such as medulloblastomas and primitive neuroectodermal tumors) by RT-PCR with the specific primers for O6-methylguanine DNA methyltransferase (MGMT), multidrug-resistance gene 1 (MDR1), multidrug-resistance-associated protein (MRP), and glutathione-S-transferase-pi (GST-pi). Thirty-seven preliminary individual adjuvant therapies (IAT) based on RT-PCR results, mainly in MGMT expression, were performed on 30 consecutive patients with neuroepithelial tumors. In the retrospectively examined series, the initial response to 1-(4-amino-2-methyl-5-pyrimidynyl) methyl-3-(2-chloroethyl)-3-nitrosourea hydrochloride (ACNU) was correlated most significantly to the MGMT mRNA expression among 11 independent prognostic factors (p = 0.0037) in multivariate logistic regression analysis. In the preliminary IAT, 17 of 32 evaluable therapies had a partial or complete response (53.1% response rate). Our IAT based on RT-PCR seemed to be more effective than conventional therapies for malignant gliomas.