Prognostic factors in high-grade malignant glioma. A multivariate analysis of 76 cases with postoperative radiotherapy.

PURPOSE

Patients with malignant gliomas have a limited survival prognosis. We retrospectively analyzed data of malignant glioma patients with the aim of defining prognostic factors on which individualized treatment strategies might be built on.

PATIENTS AND METHODS

Seventy-six patients with primary malignant glioma (51 glioblastoma multiforme, 20 anaplastic astrocytoma, 4 anaplastic oligo-astrocytoma, 1 anaplastic glioma) were postoperatively irradiated with 5 and 8 Me V photons, 2 Gy per fraction to a median total dose of 60 Gy (range 50 to 70 Gy).

RESULTS

The youngest quartile of patients (up to 45 years) had the highest 3-year survival rates (mean +/- SE: 15 +/- 8%) and median survival time (17.9 months, 95% confidence interval: 9.2, 24.2 months) as compared to the oldest quartile (> 61 years) with no 3-year survivor and a median survival time of 9.7 months (7.2, 12.3 months). The middle quartiles (46 to 61 years) showed intermediate results. The difference between the youngest and oldest quartile (p = 0.01) and the middle quartile versus the oldest quartile (p = 0.04) was significant. In univariate analysis, tumor size (p = 0.04 for -30 mm vs > 50 mm) was of importance. In multivariate analysis only age of the patient reached statistical significance (p = 0.03). As compared to the youngest quartile of patients, the oldest quartile had a relative risk of 2.1 (95% confidence interval: 0.9, 5.1) of dying from the disease; the age group of 46 to 61 years had a relative risk of 2.0 (0.9, 4.3).

CONCLUSIONS

Age of the patient is the most important factor for survival prognosis favouring younger age (< or = 45 years). The possible implications for radiation therapy are discussed.