Patterns of recurrence after complete remission with definitive radiotherapy in the treatment of malignant glioma

Background: In patients with malignant glioma, neuroimaging studies cannot identify the true tumor margins, and tumor disappearance on neuroimaging studies does not necessarily indicate histologic disappearance of the tumor. Methods: Patterns of recurrence and survival times were studied retrospectively in 21 patients with glioblastoma and 16 patients with anaplastic astrocytoma, whose tumor had disappeared on neuroimaging studies after treatment. Results: Thirteen patients with glioblastoma and 8 patients with anaplastic astrocytoma developed a local recurrence alone. Four patients with glioblastoma developed both a local recurrence and seeding metastasis. Five patients with anaplastic astrocytoma were recurrence free. Overall 5- year survivals were 0% and 60% in patients with glioblastoma and anaplastic astrocytoma, respectively. Conclusion: Long-term local control was not generally obtainable in glioblastoma; however, it was obtainable in anaplastic astrocytoma.