Intracerebral neutron brachytherapy for hemispheric glioblastoma multiforme. A pilot study.

The University of Kentucky Brain Tumor Study and Research Group has developed a new treatment protocol of interstitial brain brachytherapy using Californium-252 neutron source implantation in 1980. Only patients with malignant gliomas were eligible for this pilot study. Nine patients entered the Phase I trial of the protocol study between November 1980 and October 1981. According to the design of the protocol, all patients who had a verified histologic diagnosis of glioblastoma multiforme underwent postoperative intracerebral Cf-252 neutron source implantation, followed by 6 000 cGy of external photon beam irradiation. The purpose of this pilot study was to test the feasibility of interstitial Cf-252 neutron source implantation and only one implant afterloading applicator was used for brachytherapy. The implant applicator was placed in the center of tumor and the procedure was performed under CT guidance. In the assessment of the procedure, Karnofsky functional performance status, intellectual status, neurological examination, CT scans, and complications were used. All patients tolerated the procedure well and no serious complications were encountered. Despite the quality of these early treatments, there was some evidence of short-term benefit in duration of survival of the patients. We believe that further technical improvement to achieve an adequate isodose distribution to cover the tumor volume might result in longer duration improvement in survival.