Efficacy and patient-reported outcomes with dose-intense temozolomide in patients with newly diagnosed pure and mixed anaplastic oligodendroglioma: a phase II multicenter study

Standard initial therapy for patients with pure and mixed anaplastic oligodendrogliomas (AO/MAO) includes chemotherapy and radiation therapy. Anaplastic oligodendrogliomas with 1p/19q co-deletion are more responsive to chemotherapy. There is concern for potential long-term CNS toxicity of radiation. Hence an approach using chemotherapy initially and reserving radiation for progressive disease is attractive. This multicenter phase II trial included patients with newly diagnosed AO/MAO with central pathology review and 1p/19q assay. Temozolomide was given 150 mg/m² days 1–7 and 15–21, every 28 days for 8 cycles. The primary endpoint was progression free survival (PFS). Secondary endpoints included response rate, overall survival (OS), treatment toxicity and health-related quality of life (HRQL). Data from 62 patients enrolled between December 2001 and April 2007 at seven centers were analyzed. Among patients with measurable disease, 8 % achieved complete remission, 56 % had stable disease and 36 % had progression. The median PFS and OS were 27.2 months (95 % CI 11.9–36.3) and 105.8 months (95 % CI 51.5–N/A), respectively. Both 1p loss and 1p/19q co-deletion were positive prognostic factors for PFS (p < 0.001) and OS (p < 0.001); and there was some suggestion that 1p/19q co-deletion also predicted better response to chemotherapy (p = 0.007). Grade 3/4 toxicities were mainly hematological. Significantly improved HRQL in the future uncertainty domain of the brain cancer module was seen after cycle 4 (p < 0.001). This trial achieved outcomes similar to those reported previously. Toxicities from dose-intense temozolomide were manageable. Improvement in at least one HRQL domain increased over time. This trial supports the further study of first-line temozolomide monotherapy as an alternative to radiation therapy for patients with newly diagnosed AO/MAO with 1p 19q co-deleted tumors.