Pulsed reduced dose-rate radiotherapy: case report

摘要: The initial management of malignant gliomas is multimodality in nature, consisting surgery, radiation therapy and chemotherapy. However, once progression has occurred, treatment options are limited both terms selection efficacy. We report a case 37 year-old male diagnosed with Grade II astrocytoma initially treated surgery external beam 54 Gy delivered 1.8 fractions that subsequently progressed to IV astrocytoma. This was managed temozolomide chemotherapy until the patient exhibited further progression. Although had received prior full dose radiotherapy, he re-treated radiotherapy at substantially reduced dose-rate. reduction dose-rate obtained by delivering series 0.2 pulses separated 3 min time intervals, creating an apparent rate 0.0667 Gy/min. region recurrence 50 using 25 daily 2.0 Gy. radiographic response clinical improvement following re-irradiation pulsed no acute or late neurologic toxicities when other were not available. Despite 104 tumor bed surrounding brain parenchyma, there evidence radiation-induced normal tissue necrosis. radiobiologic basis for use recurrent glioma patients discussed.