Interstitial iodine 125 and concomitant cisplatin followed by hyperfractionated external beam irradiation for malignant supratentorial glioma: Preliminary experience at the University of Tennessee, Memphis

Between November 1989 and October 1992, 28 consecutive patients with glioblastoma multiforme (n = 18) or anaplastic astrocytoma (n = 10; includes one patient with oligodendroglioma with anaplastic astrocytoma component) were treated with interstitial iodine 125 (60 Gy over 6 days) and with concomitant cisplatin (via infusion on days 2-6 of the implant), then followed by hyperfractionated external beam irradiation (110 cGy delivered twice daily; 66 Gy planned total dose). Of 26 patients (60%) who received both ¹²⁵I and HEBI, 15 are alive with no evidence of recurrent disease at a median follow-up of 18 months post-¹²⁵I (range: 11 to 34 months). Four other disease-free patients succumbed to nontumor-related events. Two patients with local control had distant failure outside the HEBI treatment fields. Overall local control is 77%. Local failure occurred in 6 patients (23%) 2 to 11 months post-¹²⁵I. Time to disease progression ranged from 4 to 18 months (median: 10 months). Survival (measured from the date of diagnosis) has ranged from 6 to 26 months (median: 15 months). All patients have maintained Karnofsky Performance Status within 20 points of their preimplant status, with the exception of a single patient who, following diagnosis of radiation necrosis and surgical intervention for symptomatic relief, had a 30-point drop in KPS. Radiation necrosis or persistent mass effect were noted by neuroimaging in seven patients, four of whom required surgical intervention following failed medical management. Ototoxicity, nephrotoxicity, peripheral nerve dysfunction, or hematologic toxicities have not been observed. This new innovative treatment approach offers a promising alternative to the normally dismal prognosis for patients with malignant gliomas.