LOCAL APPLICATION OF RADIOLABELED MONOCLONAL-ANTIBODIES IN THE TREATMENT OF HIGH-GRADE MALIGNANT GLIOMAS - A 6-YEAR CLINICAL-EXPERIENCE

BACKGROUND, Infusion of radiolabeled monoclonal antibodies (MAbs) dire ctly into a tumor or into the site of disease after surgery concentrat es a high quantity of antibody and radioisotope in the neoplastic tiss ue. The strong irradiation delivered by this method can result in cont rol of high grade malignant gliomas. METHODS, Antitenascin MAbs BC-2 a nd BC-4 labeled with I-131 (mean dose, 1998 MBq) were injected into 10 5 patients with malignant glioma by means of an indwelling catheter. M ultiple courses (up to six) were given. The patients underwent MAb tre atment after their tumors were minimized by surgery, radiotherapy, and , in recurrent lesions, a second operation. Data is presented in this article for 62 evaluable patients with high grade malignant gliomas (5 8 glioblastomas and 4 anaplastic astrocytomas), of which 31 were newly diagnosed tumors and 31 were recurrent lesions. In 40 cases the disea se was minimal at the time of MAb injection, and in 22 cases a macrosc opic remnant was present. RESULTS, There were very few adverse effects , all of which were minor. The treatment yielded a significant extensi on of patients' median survival (23 months) and of the disease free ti me to relapse (12 months). Favorable objective responses were recorded as follows: 9 partial responses, 3 complete responses, and 20 with no evidence of disease. A response rate of 51.6% was calculated for all assessable patients. The most important factor in obtaining beneficial outcomes was limited extension of the neoplasm at the time of therapy . CONCLUSIONS, In selected patients, locoregional radioimmunotherapy c an be included in a multimodal strategy to control high grade malignan t gliomas and produce favorable results. (C) 1997 American Cancer Soci ety.