Glioblastoma: clinical characteristics, prognostic factors and survival in 492 patients.

Objective: Glioblastoma is the most common and most malignant primary brain tumor in adults. The only overall accepted independent prognostic factors are patient age and performance. We present a large single institution patient series examined for prognostic factors using uni- and multivariate survival analysis.

Methods: 492 patients were included who underwent craniotomy for newly diagnosed glioblastoma WHO grade IV between 1990 and 2007 at our department. The association to patient survival was estimated using log-rank test for univariate analysis and cox regression method for multivariate analysis.

Results: Median patient age was 62 years (mean: 60.4 years, range: 22-93 years), the male: female ratio was 1.26:1. Primary genesis was found in 91.0% of cases. A multifocal tumor was present in 110 cases (22.4%). The median pre- and post-operative Karnofsky Performance Score was 70. Total tumor resection was performed in 288 cases (58.5%), subtotal removal in 134 cases (27.2%). The following parameters were significantly associated with survival in univariate analysis: age, performance, primary genesis, multifocal tumor, neurological deficit, neuropsychological findings, seizures, incidental finding, total or subtotal resection, radiotherapy, chemotherapy, combined radio-/chemotherapy with temozolomide, re-craniotomy, second tumor in patient history. The following parameters were significantly associated with survival in multivariate analysis: age, performance, multifocal tumor, total or subtotal resection, radiotherapy, chemotherapy, combined radio-/chemotherapy with temozolomide.

Conclusion: In addition to patient age and performance, we identified multiple lesions and resection status as independent prognostic factors. Radiotherapy, chemotherapy and combined radio-/chemotherapy with temozolomide were significantly associated with prolonged survival.