Abstract: Malignant glioma is treated mainly by surgery with chemotherapy and external radiotherapy as adjuvant remedies. Survival time can be prolonged if appropriate radioimmunotherapy is employed as another concurrent alternative. Per-clinical, clinical phase I and II studies of ¹³¹I and ⁹⁰Y labeled anti-tenascin monoclonal antibodies in the treatment of malignant glioma have resulted in satisfactory therapeutic efficacy.