Meta-analytic re-evaluation of misonidazole in the treatment of high grade astrocytoma.

BACKGROUND

The clinical effects of the radiation sensitizer, misonidazole, in the treatment of high grade astrocytoma are equivocal based on available clinical trial data. A meta-analysis was performed in order to evaluate the impact of this compound on treatment outcome for this disease.

METHODS

One year survival data derived from over 1,700 patients enrolled in 9 randomized clinical trials were analyzed using the meta-analytic techniques previously described by Peto et al. This analysis compared the proportion of patients surviving one year treated with misonidazole sensitized radiation therapy (+/- chemotherapy) versus radiation alone (+/- chemotherapy).

RESULTS

A summary odds ratio was calculated following a statistical analysis showing a lack of heterogeneity among the included studies in terms of their estimate of effect. The calculated Peto odds ratio was 0.92 with a 95% confidence interval of 0.77-1.09. These data indicate that misonidazole treatment is associated with an approximately 8% improved 1 year survival compared with non-misonidazole treatment arms. This odds ratio increased to 0.87 when only those trials using "conventional" radiation therapy schedules were analyzed.

CONCLUSION

This analysis suggests that misonidazole may contribute to improved 1 year survival in patients with high grade astrocytoma and that the magnitude of this improvement may be comparable to that seen with the use of chemotherapy in this patient group.