Local application of radiolabeled monoclonal antibodies in the treatment of high grade malignant gliomas: a six-year clinical experience.

BACKGROUND

Infusion of radiolabeled monoclonal antibodies (MAbs) directly into a tumor or into the site of disease after surgery concentrates a high quantity of antibody and radioisotope in the neoplastic tissue. The strong irradiation delivered by this method can result in control of high grade malignant gliomas.

METHODS

Antitenascin MAbs BC-2 and BC-4 labeled with 131I (mean dose, 1998 MBq) were injected into 105 patients with malignant glioma by means of an in-dwelling catheter. Multiple courses (up to six) were given. The patients underwent MAb treatment 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 (58 glioblastomas and 4 anaplastic astrocytomas), of which 31 were newly diagnosed tumors and 31 were recurrent lesions. In 40 cases the disease was minimal at the time of MAb injection, and in 22 cases a macroscopic remnant was present.

RESULTS

There were very few adverse effects, all of which were minor. The treatment yielded a significant extension of patients' median survival (23 months) and of the disease free time 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 can be included in a multimodal strategy to control high grade malignant gliomas and produce favorable results.