Malignant gliomas have been difficult to treat with chemotherapy. The most effective agent, BCNU (carmustine), has considerable systemic toxicity and a short half-life in serum. To obviate these problems, a method has been developed for the local sustained release of chemotherapeutic agents by their incorporation into biodegradable polymers. Implantation of the drug-impregnated polymer at the tumor site allows prolonged local exposure with minimal systemic exposure. In this Phase I-II study, 21 patients with recurrent malignant glioma were treated with BCNU released interstitially by means of a polyanhydride biodegradable polymer implant. Up to eight polymer wafers were placed in the resection cavity intraoperatively, upon completion of tumor debulking. The polymer releases the therapeutic drug for approximately 3 weeks. Three increasing concentrations of BCNU were studied; the treatment was well tolerated at all three levels. There were no adverse reactions to the BCNU wafer treatment itself. The average survival period after reoperation was 65 weeks for the first dose group, 64 weeks for the second dose group, and 32 weeks for the highest dose group. The overall mean survival time was 48 weeks from reoperation and 94 weeks from the original operation. The overall median survival times were 46 weeks postimplant and 87 weeks from initial surgery. Eighteen (86%) of 21 patients lived more than 1 year from the time of their initial diagnosis and eight (38%) of 21 patients lived more than 1 year after intracranial implantation of the polymer. Frequent hematology, blood chemistry, and urinalysis tests did not reveal any systemic effect from this interstitial chemotherapy. Since the therapy is well tolerated and safe, a placebo-controlled clinical trial has been started. The trial will measure the effect of the second treatment dose on survival of patients with recurrent malignant glioma.
To provide baseline information for the "local" therapy of the glioblastoma multiforme (GBM), whole-brain histological sections of 15 untreated GBM's were studied to determine the distribution of neoplastic cells. These findings were then compared with the computerized tomography (CT) scans in 11 cases in order to determine the extent to which the peripheral portion of the neoplasm can be estimated by the presence of a low-density area without contrast enhancement. The results of the histological study confirmed the marked heterogeneity of GBM's and disclosed a great variability in the geometry, extent, and character of the peripheral "infiltrating" margin. In spite of the widely held concept that glioblastomas are localized within 2 cm of the contrast-enhanced rim, there were three cases in this two-dimensional study in which this distance was exceeded, and it seems likely that three-dimensional reconstructions would have detected additional cases in which neoplastic cells extended beyond this arbitrary limit. Only three of the 15 GBM's were restricted to the distribution of one internal carotid or one vertebral artery. To the extent that the neoplasms in the present series are representative, this suggests that glioblastomas will be difficult to treat successfully by intra-arterial therapy using existing therapeutic agents. Correlations of histological sections with the CT scans revealed that the vast majority of the neoplastic tissue was contained within the contrast-enhancing and "peritumoral" areas of low density, but that in five cases fingers of neoplasm extended for short distances beyond the outer margin of the latter region. This indicates that the distribution of cells of a GBM cannot be inferred from CT images since the "peritumoral" area of low density can over- or underestimate the extent of the lesion.
Within 3 weeks of definitive surgery, 571 adult patients with histologically confirmed, supratentorial malignant gliomas were randomly assigned to receive one of three chemotherapy regimens: BCNU (1,3-bis(2-chloroethyl)-1-nitrosourea) alone, alternating courses (every 8 weeks) of BCNU and procarbazine, or BCNU plus hydroxyurea alternating with procarbazine plus VM-26 (epipodophyllotoxin). Patients accrued in 1980 and 1981 were to receive 6020 rads of whole-brain radiotherapy concurrent with the first course of chemotherapy. Patients accrued in 1982 and 1983 were randomly assigned to receive either whole-brain irradiation as above, or 4300 rads of whole-brain radiotherapy plus 1720 rads coned down to to the tumor volume. The data were analyzed for the total randomized population and separately for the 510 patients, termed the "Valid Study Group (VSG)," who met protocol eligibility specifications (including central pathology review), 80% of whom had glioblastoma multiforme. The median survival times from time of randomization for the three chemotherapy groups of the VSG ranged from 11.3 to 13.8 months, and 29% to 37% of the patients survived for 18 months (life-table estimate); the differences between these groups were not statistically significant. Survival differences between the radiotherapy groups were small and not statistically significant. It is concluded that, for malignant glioma, giving part of the radiotherapy by coned-down boost is as effective as full whole-brain irradiation, and that multiple-drug chemotherapy as outlined in this protocol conferred no significant survival advantage over BCNU alone.
This Phase III trial tested the efficacy and safety of intra-arterial 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) for the treatment of newly resected malignant glioma, comparing intra-arterial BCNU and intravenous BCNU (200 mg/sq m every 8 weeks), each regimen without or with intravenous 5-fluorouracil (1 gm/sq m three times daily given 2 weeks after BCNU). All patients also received radiation therapy. A total of 505 patients were randomly assigned within the study. Fifty-seven patients were excluded, primarily because of neuropathology error, and the remaining 448 patients constituted the Valid Study Group. Of the total 505 patients, 190 patients could not receive intra-arterial BCNU and 315 patients were randomly assigned to receive intra-arterial (167 patients) and intravenous (148 patients) BCNU. Actuarial analysis (log-rank) demonstrated reduced survival for the intra-arterial group (p = 0.03). Serious toxicity was observed in the intra-arterial group; 16 patients (9.5%) developed irreversible encephalopathy with computerized tomography evidence of cerebral edema, and 26 patients (15.5%) developed visual loss ipsilateral to the infused carotid artery. Administration of 5-fluorouracil did not influence survival. The survival rate between the intravenous and the intra-arterial BCNU patients with glioblastoma multiforme did not differ, but was worse for intra-arterial BCNU patients with anaplastic astrocytoma than for those receiving intravenous BCNU (p = 0.002). Neuropathologically, intra-arterial BCNU produced white matter necrosis. It is concluded that intra-arterial BCNU is neither safe nor effective in prolonging survival when administered by the methods used in this study of newly diagnosed patients with malignant glioma.
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