A randomized trial of accelerated hyperfractionated radiation therapy and bis-chloroethyl nitrosourea for malignant glioma. A preliminary report of Radiation Therapy Oncology Group 83-02

Accelerated hyper-versus normofractionated radiochemotherapy with temozolomide in patients with glioblastoma: a multicenter retrospective analysis

Background and purpose

The standard treatment of glioblastoma patients consists of surgery followed by normofractionated radiotherapy (NFRT) with concomitant and adjuvant temozolomide chemotherapy. Whether accelerated hyperfractionated radiotherapy (HFRT) yields comparable results to NFRT in combination with temozolomide has only sparsely been investigated. The objective of this study was to compare NFRT with HFRT in a multicenter analysis.

Materials and methods

A total of 484 glioblastoma patients from four centers were retrospectively pooled and analyzed. Three-hundred-ten and 174 patients had been treated with NFRT (30 × 1.8 Gy or 30 × 2 Gy) and HFRT (37 × 1.6 Gy or 30 × 1.8 Gy twice/day), respectively. The primary outcome of interest was overall survival (OS) which was correlated with patient-, tumor- and treatment-related variables via univariable and multivariable Cox frailty models. For multivariable modeling, missing covariates were imputed using multiple imputation by chained equations, and a sensitivity analysis was performed on the complete-cases-only dataset.

Results

After a median follow-up of 15.7 months (range 0.8–88.6 months), median OS was 16.9 months (15.0–18.7 months) in the NFRT group and 14.9 months (13.2–17.3 months) in the HFRT group (p = 0.26). In multivariable frailty regression, better performance status, gross-total versus not gross-total resection, MGMT hypermethylation, IDH mutation, smaller planning target volume and salvage therapy were significantly associated with longer OS (all p < 0.01). Treatment differences (HFRT versus NFRT) had no significant effect on OS in either univariable or multivariable analysis.

Conclusions

Since HFRT with temozolomide was not associated with worse OS, we assume HFRT to be a potential option for patients wishing to shorten their treatment time.

Treatment of newly diagnosed glioblastoma in the elderly: a network meta-analysis

BACKGROUND

A glioblastoma is a fatal type of brain tumour for which the standard of care is maximum surgical resection followed by chemoradiotherapy, when possible. Age is an important consideration in this disease, as older age is associated with shorter survival and a higher risk of treatment-related toxicity.

OBJECTIVES

To determine the most effective and best-tolerated approaches for the treatment of elderly people with newly diagnosed glioblastoma. To summarise current evidence for the incremental resource use, utilities, costs and cost-effectiveness associated with these approaches.

SEARCH METHODS

We searched electronic databases including the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE and Embase to 3 April 2019, and the NHS Economic Evaluation Database (EED) up to database closure. We handsearched clinical trial registries and selected neuro-oncology society conference proceedings from the past five years.

SELECTION CRITERIA

Randomised trials (RCTs) of treatments for glioblastoma in elderly people. We defined 'elderly' as 70+ years but included studies defining 'elderly' as over 65+ years if so reported.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods for study selection and data extraction. Where sufficient data were available, treatment options were compared in a network meta-analysis (NMA) using Stata software (version 15.1). For outcomes with insufficient data for NMA, pairwise meta-analysis were conducted in RevMan. The GRADE approach was used to grade the evidence.

MAIN RESULTS

We included 12 RCTs involving approximately 1818 participants. Six were conducted exclusively among elderly people (either defined as 65 years or older or 70 years or older) with newly diagnosed glioblastoma, the other six reported data for an elderly subgroup among a broader age range of participants. Most participants were capable of self-care. Study quality was commonly undermined by lack of outcome assessor blinding and attrition. NMA was only possible for overall survival; other analyses were pair-wise meta-analyses or narrative syntheses. Seven trials contributed to the NMA for overall survival, with interventions including supportive care only (one trial arm); hypofractionated radiotherapy (RT40; four trial arms); standard radiotherapy (RT60; five trial arms); temozolomide (TMZ; three trial arms); chemoradiotherapy (CRT; three trial arms); bevacizumab with chemoradiotherapy (BEV_CRT; one trial arm); and bevacizumab with radiotherapy (BEV_RT). Compared with supportive care only, NMA evidence suggested that all treatments apart from BEV_RT prolonged survival to some extent. Overall survival High-certainty evidence shows that CRT prolongs overall survival (OS) compared with RT40 (hazard ratio (HR) 0.67, 95% confidence interval (CI) 0.56 to 0.80) and low-certainty evidence suggests that CRT may prolong overall survival compared with TMZ (TMZ versus CRT: HR 1.42, 95% CI 1.01 to 1.98). Low-certainty evidence also suggests that adding BEV to CRT may make little or no difference (BEV_CRT versus CRT: HR 0.83, 95% CrI 0.48 to 1.44). We could not compare the survival effects of CRT with different radiotherapy fractionation schedules (60 Gy/30 fractions and 40 Gy/15 fractions) due to a lack of data. When treatments were ranked according to their effects on OS, CRT ranked higher than TMZ, RT and supportive care only, with the latter ranked last. BEV plus RT was the only treatment for which there was no clear benefit in OS over supportive care only.   One trial comparing tumour treating fields (TTF) plus adjuvant chemotherapy (TTF_AC) with adjuvant chemotherapy alone could not be included in the NMA as participants were randomised after receiving concomitant chemoradiotherapy, not before. Findings from the trial suggest that the intervention probably improves overall survival in this selected patient population. We were unable to perform NMA for other outcomes due to insufficient data. Pairwise analyses were conducted for the following. Quality of life Moderate-certainty narrative evidence suggests that overall, there may be little difference in QoL between TMZ and RT, except for discomfort from communication deficits, which are probably more common with RT (1 study, 306 participants, P = 0.002). Data on QoL for other comparisons were sparse, partly due to high dropout rates, and the certainty of the evidence tended to be low or very low. Progression-free survival High-certainty evidence shows that CRT increases time to disease progression compared with RT40 (HR 0.50, 95% CI 0.41 to 0.61); moderate-certainty evidence suggests that RT60 probably increases time to disease progression compared with supportive care only (HR 0.28, 95% CI 0.17 to 0.46), and that BEV_RT probably increases time to disease progression compared with RT40 alone (HR 0.46, 95% CI 0.27 to 0.78). Evidence for other treatment comparisons was of low- or very low-certainty. Severe adverse events Moderate-certainty evidence suggests that TMZ probably increases the risk of grade 3+ thromboembolic events compared with RT60 (risk ratio (RR) 2.74, 95% CI 1.26 to 5.94; participants = 373; studies = 1) and also the risk of grade 3+ neutropenia, lymphopenia, and thrombocytopenia. Moderate-certainty evidence also suggests that CRT probably increases the risk of grade 3+ neutropenia, leucopenia and thrombocytopenia compared with hypofractionated RT alone. Adding BEV to CRT probably increases the risk of thromboembolism (RR 16.63, 95% CI 1.00 to 275.42; moderate-certainty evidence). Economic evidence There is a paucity of economic evidence regarding the management of newly diagnosed glioblastoma in the elderly. Only one economic evaluation on two short course radiotherapy regimen (25 Gy versus 40 Gy) was identified and its findings were considered unreliable.

AUTHORS' CONCLUSIONS

For elderly people with glioblastoma who are self-caring, evidence suggests that CRT prolongs survival compared with RT and may prolong overall survival compared with TMZ alone. For those undergoing RT or TMZ therapy, there is probably little difference in QoL overall. Systemic anti-cancer treatments TMZ and BEV carry a higher risk of severe haematological and thromboembolic events and CRT is probably associated with a higher risk of these events. Current evidence provides little justification for using BEV in elderly patients outside a clinical trial setting. Whilst the novel TTF device appears promising, evidence on QoL and tolerability is needed in an elderly population. QoL and economic assessments of CRT versus TMZ and RT are needed. More high-quality economic evaluations are needed, in which a broader scope of costs (both direct and indirect) and outcomes should be included.

Accelerated hyperfractionated radiochemotherapy with temozolomide is equivalent to normofractionated radiochemotherapy in a retrospective analysis of patients with glioblastoma

Background

Current standard of treatment for newly diagnosed patients with glioblastoma (GBM) is surgical resection with adjuvant normofractionated radiotherapy (NFRT) combined with temozolomide (TMZ) chemotherapy. Hyperfractionated accelerated radiotherapy (HFRT) which was known as an option from randomized controlled trials before the temozolomide era has not been compared to the standard therapy in a randomized setting combined with TMZ.

Methods

Data of 152 patients with newly diagnosed GBM treated from 10/2004 until 7/2018 at a single tertiary care institution were extracted from a clinical database and retrospectively analyzed. Thirty-eight patients treated with NFRT of 60 Gy in 30 fractions (34 with simultaneous and 2 with sequential TMZ) were compared to 114 patients treated with HFRT of 54.0 Gy in 30 fraction of 1.8 Gy twice daily (109 with simultaneous and 3 with sequential TMZ). The association between treatment protocol and other variables with overall survival (OS) was assessed using univariable and multivariable Cox regression analysis; the latter was performed using variables selected by the LASSO method.

Results

Median overall survival (OS) was 20.3 month for the entire cohort. For patients treated with NFRT median OS was 24.4 months compared to 18.5 months in patients treated with HFRT (p = 0.131). In univariable regression analysis the use of dexamethasone during radiotherapy had a significant negative impact on OS in both patient groups, HR 2.21 (95% CI 1.47–3.31, p = 0.0001). In multivariable analysis adjusted for O6-methylguanine-DNA methyl-transferase (MGMT) promotor methylation status, salvage treatment and secondary GBM, the use of dexamethasone was still a negative prognostic factor, HR 1.95 (95% CI 1.21–3.13, p = 0.006). Positive MGMT-methylation status and salvage treatment were highly significant positive prognostic factors. There was no strong association between treatment protocol and OS (p = 0.504).

Conclusions

Our retrospective analysis supports the hypothesis of equivalence between HFRT and the standard protocol of treatment for GBM. For those patients who are willing to obtain the benefit of shortening the course of radiochemotherapy, HFRT may be an alternative with comparable efficacy although it was not yet tested in a large prospective randomized study against the current standard. The positive influence of salvage therapy and negative impact of concomitant use of corticosteroids should be addressed in future prospective trials. To confirm our results, we plan to perform a pooled analysis with other tertiary clinics in order to achieve better statistical reliability.

Clinical Results of Unconventional Fractionation Radiotherapy in Central Nervous System Tumors

Malignant brain tumors (primary and metastatic) are apparently resistant to most therapeutic efforts. Several randomized trials have provided evidence supporting the efficacy of radiation therapy. Attempts at improving the results of external beam radiotherapy include altered fractionation, radiation sensitizers and concomitant chemotherapy. In low-grade gliomas, all clinical studies with radiotherapy have employed conventional dose fractionation regimens. In high-grade gliomas, hypofractionation schedules represent effective palliative regimens in poor prognosis subsets of patients; short-term survival in these patients has not allowed to evaluate late toxicity. In tumors arising within the central nervous system, hyperfractionated irradiation exploits the differences in repair capacity between tumour and late responding normal tissues. It may allow for higher total dose and may result in increased tumor cell kill. Accelerated radiotherapy may reduce the repopulation of tumor cells between fractions. It may potentially improve tumor control for a given dose level, provided that there is no increase in late normal tissue injury. In supratentorial malignant gliomas, superiority of accelerated hyperfractionated over conventionally fractionated schedules was observed in a randomized trial; however, the gain in survival was less than 6 months. At present no other randomized trial supports the preferential choice for altered fractionation irradiation. Also in pediatric brainstem tumors there are no data to confirm the routine use of hyperfractionated irradiation, and significant late sequelae have been reported in the few long-term survivors. Shorter treatment courses with accelerated hyperfractionated radiotherapy may represent a useful alternative to conventional irradiation for the palliation of brain metastases. Different considerations have been proposed to explain this gap between theory and clinical data. Patients included in dose/effect studies are not stratified by prognostic factors and other treatment-related parameters. This observation precludes any definite conclusion about the relative role of conventional and of altered fractionation. New approaches are currently in progress. More prolonged radiation treatments, up to higher total doses, could delay time to tumor progression and improve survival in good prognosis subsets of patients; altered fractionation may be an effective therapeutic tool to achieve this goal.

Evaluation of Helical Tomotherapy in the Treatment of High-Grade Gliomas near Critical Structures

Background

Our purpose was to investigate the role of helical tomotherapy using a simultaneous integrated boost technique for the treatment of high-grade gliomas near intracranial critical structures.

Methods and materials

Of 27 patients treated with helical tomotherapy, 11 were eligible. Only patients whose tumors were within 0.5 cm of the optic chiasm, the optic nerve or the brainstem were included. The therapeutic approach was a simultaneous integrated boost, prescribing 66 and 60 Gy to the PTV1 and PTV2, respectively, in 30 fractions. All patients received concomitant temozolomide at a dose of 75 mg/m2 daily during radiation therapy.

Results

Of the 11 patients considered, 3 patients (27%) died after 4 months from the completion of the combined treatment. Three patients (27%) presented local progression, and the median time to disease progression was 6 months (range, 1–12). Five patients (45%), at the time of this evaluation, did not have signs or symptoms of recurrence or progression of the disease. Acute toxicity, evaluated during radiochemotherapy, was minimal, with all patients experiencing RTOG grade 0 and grade 1 toxicity.

Conclusions

Helical tomotherapy proved to be an effective and safe treatment modality, with an improvement of accuracy in delivery of highdose radiotherapy despite the presence of nearby critical structures.

Therapeutic interactions of autophagy with radiation and temozolomide in glioblastoma: evidence and issues to resolve

Glioblastoma is a unique model of non-metastasising disease that kills the vast majority of patients through local growth, despite surgery and local irradiation. Glioblastoma cells are resistant to apoptotic stimuli, and their death occurs through autophagy. This review aims to critically present our knowledge regarding the autophagic response of glioblastoma cells to radiation and temozolomide (TMZ) and to delineate eventual research directions to follow, in the quest of improving the curability of this incurable, as yet, disease. Radiation and TMZ interfere with the autophagic machinery, but whether cell response is driven to autophagy flux acceleration or blockage is disputable and may depend on both cell individuality and radiotherapy fractionation or TMZ schedules. Potent agents that block autophagy at an early phase of initiation or at a late phase of autolysosomal fusion are available aside to agents that induce functional autophagy, or even demethylating agents that may unblock the function of autophagy-initiating genes in a subset of tumours. All these create a maze, which if properly investigated can open new insights for the application of novel radio- and chemosensitising policies, exploiting the autophagic pathways that glioblastomas use to escape death.

Stress Response Leading to Resistance in Glioblastoma-The Need for Innovative Radiotherapy (iRT) Concepts

Glioblastoma (GBM) is the most common and most aggressive malignant primary brain tumor in adults. In spite of multimodal therapy concepts, consisting of surgery, radiotherapy and chemotherapy, the median survival, merely 15–18 months, is still poor. Mechanisms for resistance of GBM to radio(chemo)therapy are not fully understood yet and due to the genetic heterogeneity within the tumor including radiation-resistant tumor stem cells, there are several factors leading to therapy failure. Recent research revealed that, hypoxia during radiation and miRNAs may adversely affect the therapeutic response to radiotherapy. Further molecular alterations and prognostic markers like the DNA-repair protein O6-methylguanine-DNA methyltransferase (MGMT), anti-apoptotic molecular chaperones, and/or the activity of aldehyde dehydrogenase 1 (ALDH1) have also been identified to play a role in the sensitivity to cytostatic agents. Latest approaches in the field of radiotherapy to use particle irradiation or dose escalation strategies including modern molecular imaging, however, need further evaluation with regard to long-term outcome. In this review we focus on current information about the mechanisms and markers that mediate resistance to radio(chemo)therapy, and discuss the opportunities of Innovative Radiotherapy (iRT) concepts to improve treatment options for GBM patients.

Early toxicity predicts long-term survival in high-grade glioma

Background:

Patients with high-grade gliomas are treated with surgery followed by chemoradiation. The risk factors and implications of neurological side effects are not known.

Methods:

Acute and late ⩾ grade 3 neurological toxicities (NTs) were analysed among 2761 patients from 14 RTOG trials accrued from 1983 to 2003. The association between acute and late toxicity was analysed using a stepwise logistic regression model. The association between the occurrence of acute NT and survival was analysed as an independent variable.

Results:

There were 2610 analysable patients (86% glioblastoma, 10% anaplastic astrocytoma). All received a systemic agent during radiation (83% chemotherapy, 17% biological agents). Median radiation dose was 60 Gy. There were 182 acute and 83 late NT events. On univariate analysis, older age, poor performance status, aggressive surgery, pre-existing neurological dysfunction, poor mental status and twice-daily radiation were associated with increased acute NT. In a stepwise logistic regression model the occurrence of acute NT was significantly associated with late NT (OR=2.40; 95% CI=1.2–4.8; P=0.014). The occurrence of acute NT predicted poorer overall survival, independent of recursive partitioning analysis class (median 7.8 vs 11.8 months).

Interpretation:

Acute NT is significantly associated with both late NT and overall survival.

Radiotherapy and temozolomide for newly diagnosed glioblastoma and anaplastic astrocytoma: validation of Radiation Therapy Oncology Group-Recursive Partitioning Analysis in the IMRT and temozolomide era

Since the development of the Radiation Therapy Oncology Group-Recursive Partitioning Analysis (RTOG-RPA) risk classes for high-grade glioma, radiation therapy in combination with temozolomide (TMZ) has become standard care. While this combination has improved survival, the prognosis remains poor in the majority of patients. Therefore, strong interest in high-grade gliomas from basic research to clinical trials persists. We sought to evaluate whether the current RTOG-RPA retains prognostic significance in the TMZ era or alternatively, if modifications better prognosticate the optimal selection of patients with similar baseline prognosis for future clinical protocols. The records of 159 patients with newly-diagnosed glioblastoma (GBM, WHO grade IV) or anaplastic astrocytoma (AA, WHO grade III) were reviewed. Patients were treated with intensity-modulated radiation therapy (IMRT) and concurrent followed by adjuvant TMZ (n = 154) or adjuvant TMZ only (n = 5). The primary endpoint was overall survival. Three separate analyses were performed: (1) application of RTOG-RPA to the study cohort and calculation of subsequent survival curves, (2) fit a new tree model with the same predictors in RTOG-RPA, and (3) fit a new tree model with an expanded predictor set. All analyses used a regression tree analysis with a survival outcome fit to formulate new risk classes. Overall median survival was 14.9 months. Using the RTOG-RPA, the six classes retained their relative prognostic significance and overall ordering, with the corresponding survival distributions significantly different from each other (P < 0.01, χ² statistic = 70). New recursive partitioning limited to the predictors in RTOG-RPA defined four risk groups based on Karnofsky Performance Status (KPS), histology, age, length of neurologic symptoms, and mental status. Analysis across the expanded predictors defined six risk classes, including the same five variables plus tumor location, tobacco use, and hospitalization during radiation therapy. Patients with excellent functional status, AA, and frontal lobe tumors had the best prognosis. For patients with newly-diagnosed high-grade gliomas, RTOG-RPA classes retained prognostic significance in patients treated with TMZ and IMRT. In contrast to RTOG-RPA, in our modified RPA model, KPS rather than age represented the initial split. New recursive partitioning identified potential modifications to RTOG-RPA that should be further explored with a larger data set.

Optimizing radiotherapy schedules for elderly glioblastoma multiforme patients

Glioblastoma is the most common malignant primary brain tumor. Despite recent advances, the overall prognosis remains poor with median survivals of approximately 1 year and 5-year survivals of less than 5%. Efforts at risk stratification have identified age and performance status as the most important prognostic features. It is well established that patients treated with postoperative radiation therapy have improved survival and functional capacity compared with unirradiated patients. Recent evidence suggests that the benefit of postoperative radiation persists even within the cohort aged 70 years or over. Some investigators have questioned whether the standard treatment schedule of 60 Gy delivered over a 6-week period is necessary for older patients with limited functional status. Alternative treatment schedules have been devised to reduce the inconvenience and morbidity of standard therapy. This review aims to evaluate the current state of knowledge on alternative radiotherapy schedules for elderly and poor-prognosis patients with glioblastoma.

A phase II trial of accelerated radiotherapy using weekly stereotactic conformal boost for supratentorial glioblastoma multiforme: RTOG 0023

PURPOSE

This phase II trial was performed to assess the feasibility, toxicity, and efficacy of dose-intense accelerated radiation therapy using weekly fractionated stereotactic radiotherapy (FSRT) boost for patients with glioblastoma multiforme (GBM).

METHODS AND MATERIALS

Patients with histologically confirmed GBM with postoperative enhancing tumor plus tumor cavity diameter <60 mm were enrolled. A 50-Gy dose of standard radiation therapy (RT) was given in daily 2-Gy fractions. In addition, patients received four FSRT treatments, once weekly, during Weeks 3 to 6. FSRT dosing of either 5 Gy or 7 Gy per fraction was given for a cumulative dose of 70 or 78 Gy in 29 (25 standard RT + 4 FSRT) treatments over 6 weeks. After the RT course, carmustine (BCNU) at 80 mg/m(2) was given for 3 days, every 8 weeks, for 6 cycles.

RESULTS

A total of 76 patients were analyzed. Toxicity included: 3 Grade 4 chemotherapy, 3 acute Grade 4 radiotherapy, and 1 Grade 3 late. The median survival time was 12.5 months. No survival difference is seen when compared with the RTOG historical database. Patients with gross total resection (41%) had a median survival time of 16.6 months vs. 12.0 months for historic controls with gross total resection (p = 0.14).

CONCLUSION

This first, multi-institutional FSRT boost trial for GBM was feasible and well tolerated. There is no significant survival benefit using this dose-intense RT regimen. Subset analysis revealed a trend toward improved outcome for GTR patients suggesting that patients with minimal disease burden may benefit from this form of accelerated RT.

An estimation of radiobiologic parameters from clinical outcomes for radiation treatment planning of brain tumor

PURPOSE

To estimate a plausible set of radiobiologic parameters such as alpha, alpha/beta values, from clinical outcomes for biologically based radiation treatment planning of brain tumors.

METHODS AND MATERIALS

Linear-quadratic (LQ) formalism and the concept of equivalent uniform dose were used to analyze a series of published clinical data for malignant gliomas involving different forms of radiation therapy.

RESULTS

A plausible set of LQ parameters was obtained for gliomas: alpha = 0.06 +/- 0.05 Gy(-1), alpha/beta = 10.0 +/- 15.1 Gy, the tumor cell doubling time T(d) = 50 +/- 30 days, with the repair half-time of 0.5 h. The present estimated biologic parameters can reasonably predict the effectiveness of most of the recently reported clinical results employing either single or combined radiation therapy modalities. Different LQ parameters between Grade 3 and Grade 4 astrocytomas were found, implying the radiosensitivity for different grade tumors may be different. Smaller alpha, beta from in vivo was observed, indicating lower radiosensitivity occurred in vivo as compared with in vitro.

CONCLUSIONS

A plausible set of radiobiologic parameters for gliomas was estimated based on clinical data. These parameters can reasonably predict most of the clinical results. They may be used to design new treatment fractionation schemes and to evaluate and optimize treatment plans.

Safety of thrice-daily hyperfractionated radiation and BCNU for high-grade gliomas

PURPOSE

To investigate the safety of thrice-daily hyperfractionated radiotherapy (RT) given in conjunction with BCNU (carmustine) in high-grade gliomas.

METHODS AND MATERIALS

Patients >18 years old with newly diagnosed high-grade gliomas were eligible. The dose of radiation was 5040 cGy, with a 1440-cGy boost in 180 cGy fractions delivered thrice daily in two 6-day periods with a 2-week interval. BCNU (200 mg/m(2)) was administered on the first day of radiation, then every 7 weeks for 1 year and every 10 weeks for another year.

RESULTS

Eighteen patients were enrolled. The mean age was 49.6 years. Sixteen patients had astrocytomas (Grade 3 or 4 in 5 and 11 patients, respectively) and 2 had oligoastrocytomas (Grade 3 and 4 in 1 patient each). One underwent total resection, 9 subtotal resection, and 8 biopsy only. Thirteen patients had stable disease, 4 regression, and 1 progression. The median time to progression was 37.8 weeks. The median overall survival was 44.4 weeks. Nine patients had neurologic toxicities, including 2 deaths at 69 and 139 weeks.

CONCLUSION

This regimen is unacceptably toxic. Factors that could have contributed to the toxicity may include the total radiation dose, thrice-daily hyperfractionation, and the concurrent use of i.v. BCNU.

Multidisciplinary management of adult anaplastic oligodendrogliomas and anaplastic mixed oligo-astrocytomas

Once thought to be rare, oligodendroglial tumors might actually represent up to 25% of primary glial neoplasms. In recent years, the histologic criteria for the diagnosis of oligodendroglioma have been broadened to include most small cell, monomorphic glial neoplasms. These refinements have led to an increased recognition of oligodendroglial neoplasms, but uniform definitions of pure versus mixed oligodendroglioma as well as the criteria for high-grade (anaplastic) versus low-grade tumors remain elusive. From a prognostic standpoint, the presence of an oligodendroglial component in a malignant glioma predicts longer survivals times for patients treated with surgery, and radiation therapy with or without chemotherapy. High rates of response to PCV (procarbazine, CCNU and Vincristine) chemotherapy also have been noted among patients with anaplastic oligodendroglial neoplasms. Ongoing prospective trials seek to clarify the role of PCV chemotherapy when added to radiation therapy and surgery. In addition, the role of molecular markers as diagnostic aides and guides to therapy and prognosis are being explored for patients with pure and mixed anaplastic oligodendroglial tumors.

Multidisciplinary management of adult anaplastic astrocytomas

The management of patients with anaplastic astrocytoma (AA) requires multidisciplinary involvement. In this article, the literature on the treatment of patients with AA is reviewed, emphasizing randomized trials and key retrospective studies. The role of surgery, radiation therapy, and chemotherapy in newly diagnosed patients and those with recurrent disease is described. Basic science insights, advances in neuroimaging and neuropathology, and novel therapies targeting invasion, angiogenesis, and growth modulation will hopefully lead to improved outcome in this subset of patients with malignant glioma.

Concurrent accelerated hyperfractionated radiation therapy and carboplatin/etoposide in patients with malignant glioma: long-term results of a phase II study

PURPOSE

Feasibility, antitumor activity and toxicity of accelerated hyperfractionated radiation therapy (Acc Hfx RT) and concurrent carboplatin/etoposide (CBDCA/VP 16) chemotherapy were investigated in patients with malignant glioma.

MATERIAL AND METHODS

Seventy-nine patients with either glioblastoma multiforme (GBM) (n = 61) or anaplastic astrocytome (AA) (n = 18) entered into a phase II study on the use of Acc Hfx RT with 60 Gy in 40 fractions in 20 treatment days over 4 weeks and concurrent CBDCA, 200 mg/m2, and VP 16, 200 mg/m2, both given once weekly during the RT course.

RESULTS

The median survival time for all 79 patients was 14 months (11 and 44 months for GBM and AA patients, respectively), while the 2- and 4-year survival was respectively 33% and 11% for all patients, 13% and 1.6% for GBM patients, and 100% and 44% for AA patients (p < 0.0001). The median time to progression for all patients was 12 months (9 and 40 months for GBM and AA, respectively), while the 2- and 4-year progression-free survival (PFS) was respectively 28% and 10% (all patients), 10% and 1.7% (GBM) and 89% and 39% (AA) (p < 0.0001). Multivariate analysis showed that age, performance status, and preoperative size of tumor influenced survival in GBM. Only 5 (6%) patients experienced grade 3 leukopenia and 6 (8%) patients experienced grade 3 thrombocytopenia. No late RT-induced toxicity was observed to date.

CONCLUSIONS

Although Acc Hfx RT/CBDCA + VP 16 was feasible and little toxic, it failed to improve survival/progression-free survival over that obtained with other currently used regimens. These results do not justify the investigation of this regimen in a phase III trial.

Phase II, two-arm RTOG trial (94-11) of bischloroethyl-nitrosourea plus accelerated hyperfractionated radiotherapy (64.0 or 70.4 Gy) based on tumor volume (> 20 or < or = 20 cm(2), respectively) in the treatment of newly-diagnosed radiosurgery-ineligible glioblastoma multiforme patients

PURPOSE

To compare survivorship, and acute and delayed toxicities following radiation therapy (RT) of radiosurgery-ineligible glioblastoma multiforme (GBM) patients treated with tumor volume-influenced, high-dose accelerated, hyperfractionated RT plus bischloroethyl-nitrosourea (BCNU), using prior RTOG malignant glioblastoma patients as historical controls.

METHODS AND MATERIALS

One hundred four of 108 patients accrued from June 1994 through May 1995 from 26 institutions were analyzable. Patients were histologically confirmed with GBM, and previously untreated. Treatment assignment (52 patients/arm) was based on tumor mass (TM), defined as the product of the maximum diameter and greatest perpendicular dimension of the titanium-gadolinium-enhanced postoperative MRI: Arm A, 64 Gy, TM > 20 cm(2); or Arm B, 70.4 Gy, TM < or = 20 cm(2). Both Arms A and B received BCNU (80 mg/m(2), under hyperhydration) days 1-3, 56-58, then 4 cycles, each 8 weeks, for a total of 6 treatment series.

RESULTS

During the 24 months immediately post-treatment, the overall median survival was 9.1 months in Arm A (64 Gy) and 11.0 months in Arm B (70.4 Gy). Median survival in recursive partitioning analysis (RPA) Class III/IV was 10.4 months in Arm A and 12.2 months in Arm B, while RPA Class V/VI was 7.6 months in Arm A and 6.1 months in Arm B. There were no grade 4 neurological toxicities in Arm A; 2 grade 4 neurological toxicities were observed in Arm B (1 motor deficit, 1 necrosis at 157 days post-treatment).

CONCLUSION

This strategy of high-dose, accelerated hyperfractionated radiotherapy shortens overall RT treatment times while allowing dose escalation, and it provides the potential for combination with currently available, as well as newer, chemotherapy agents. Survival is comparable with previously published RTOG data, and toxicities are within acceptable limits.

Accelerated hyperfractionated radiotherapy in supratentorial malignant astrocytomas

PURPOSE

To determine the safety and effectiveness of accelerated hyperfractionated radiotherapy in the treatment of supratentorial malignant astrocytomas.

MATERIALS AND METHODS

Between June 1995-July 1997, 75 patients were enrolled to a prospective phase II study. A total dose of 60 Gy was delivered in 2 Gy b.i.d. fractions with an interval of 6-8 h, 5 days per week, in an overall time of 3 weeks. The treatment protocol was planned to give 40 Gy to a treatment volume covering the contrast-enhancing lesion and oedema (+ 3-cm margin) and additional 20 Gy to the volume encompassing the contrast-enhancing lesion alone with a 1-cm margin based on preoperative magnetic resonance imaging and/or CT findings. The patients had a median age of 46 years and a median Karnofsky performance status score of 80. Histology consisted of anaplastic astrocytoma (AA) in 16 (21%) and glioblastoma multiforme (GBM) in 59 (79%) patients.

RESULTS

Median survival was 11 months for all patients; 10 months for GBM patients and 40 months for AA patients. Survival rates at 1 and 3 years were 41%, 11% for all patients; 62, 37% for AA patients and 35, 6% for GBM patients, respectively. Multivariate analysis revealed significant impact of age, histology and neurological functional class on survival. The incidence of grade 3 or worse late neurological toxicity was 5.3%.

CONCLUSIONS

Although accelerated hyperfractionated radiotherapy showed no significant advantage on survival, it shortened the treatment period from 6 to 3 weeks. Radiotherapy was well tolerated and the incidence of late toxicity is acceptable.

Accelerated radiotherapy with concomitant ACNU/Ara-C for the treatment of malignant glioma

PURPOSE

To evaluate activity and toxicity of simultaneous ACNU and Ara-C with concurrent accelerated hyperfractionated radiotherapy in the treatment of high-grade glioma.

PATIENTS AND METHODS

Thirty patients aged 23-71 years (median 47.5), 16 patients with glioblastoma multiforme (GBM) and 14 patients with grade-III glioma, received 93 courses of ACNU/Ara-C (median 4 courses) at following dose levels (ACNU/Ara-C in mg/m2/day): 70/90 (11 courses), 75/100 (36 courses) and 90/120 (46 courses). ACNU was administered IV on day 1 of each cycle, Ara-C as a 2 h-intravenous infusion on days 1-3. Patients received concomitant radiation therapy with 2 daily fractions of 1.75 Gy up to 57 Gy (median).

RESULTS

Median survival of all patients was 13 months, 11 months for GBM and > 28 months for grade-III glioma; 31% (9 patients) survived longer than 24 months. The percentage of grade IV hematological toxicity was dose-dependent: 33% at the 70/90 dose level, 40% at 75/100 and 58% at 90/120. Six patients required platelet transfusion, 1 patient red blood cells; no febrile neutropenia occurred. Among 18 patients evaluable for response, 3 (17%) showed PR, 8 (44%) NC and 7 (39%) PD at completion of chemoradiation. No acute or late neurological toxicity occurred in this study. Younger age (p = 0.0001) and grade-III histology (p = 0.0009) were important prognostic factors for prolonged survival.

CONCLUSION

This chemoradiation regimen is active in malignant gliomas and can be safely recommended at a dose level using 70 mg/m2 ACNU together with 90 mg/m2 Ara-C.

Pre-irradiation carboplatin and etoposide and accelerated hyperfractionated radiation therapy in patients with high-grade astrocytomas: a phase II study

PURPOSE

To investigate feasibility, activity and toxicity of pre-irradiation chemotherapy (CHT) in patients with newly diagnosed high-grade astrocytoma.

MATERIAL AND METHODS

Thirty-five patients with glioblastoma multiform (GBM) and ten patients with anaplastic astrocytoma (AA) entered into this study. Three weeks after surgery patients started their CHT consisting of two cycles of carboplatin (CBDCA) (C) 400 mg/m2, day 1 and etoposide (VP 16) (E) 120 mg/m2, days 1-3, given in a 3-week interval. One week after the second cycle of CE, accelerated hyperfractionated radiation therapy (ACC HFX RT) was introduced with tumor dose of 60 Gy in 40 fractions in 20 treatment days in 4 weeks, 1.5 Gy b.i.d. fractionation.

RESULTS

Responses to two cycles of CE could be evaluated in 29 (67%) of 43 patients who received it. Fourteen patients were found impossible to determine radiographic response due to an absence of post-operative contrast enhancement because they were all grossly totally resected. There were 7, 24% (95% confidence intervals - CI, 9-40%), PR (2 AA and 5 GBM), 19 SD, and 3 PD. After RT, of those 29 patients, there were 3 CR and 11 PR (overall objective response rate was 48% (95% CI, 30-67%)), 12 SD, and 3 PD. Median survival time (MST) for all 45 patients is 14 months (95% CI, 11-20 months, while median time to progression (MTP) for all patients is 12 months (95% CI, 8-16 months). Toxicities of this combined modality approach were mild to moderate, with the incidences of CHT-induced grade 3 leukopenia, being 5% (95% CI, 0-11%), and grade 3 thrombocytopenia being 7% (95% CI, 0-15%). Of RT-induced toxicity, grade 1 external otitis was observed in 26% (95% CI, 13-39%), while nausea, vomiting and somnolence were each observed in 5% (95% CI, 0-11%) patients.

CONCLUSION

Pre-irradiation CE and ACC HFX RT was a feasible treatment regimen with mild to moderate toxicity, but failed to improve results over what usually would be obtained with 'standard' approach in this patient population.

Modifying radical radiotherapy in high grade gliomas; shortening the treatment time through acceleration

PURPOSE

To evaluate the efficacy and toxicity of accelerated radiotherapy in patients with primary high grade glioma, where acceleration is used as a means of delivering a shortened course of radical radiotherapy.

PATIENTS AND METHODS

Two-hundred and eleven patients with primary high grade glioma were treated at the Royal Marsden NHS Trust between 1987 and 1997 with accelerated radiotherapy (55 Gy in 34 fractions twice daily), to planning target volume (PTV) defined as enhancing tumour and a 3 cm margin. All had histologically confirmed high grade glioma (53 anaplastic astrocytoma, 137 glioblastoma multiforme, 4 gliosarcoma, 5 gemistocytic astrocytoma, 12 high grade astrocytoma not otherwise specified). The mean Karnofsky performance status (KPS) was 90 and median age was 54 years (range 19-77).

RESULTS

Of 211 patients entered, 201 were able to complete radiotherapy; 39 patients (19%) had deterioration in KPS during radiotherapy and this was transient in 11. Median survival of 211 patients was 10 months with 1 year, 2 year, and 3 year survival probabilities of 38%, 14%, and 8% respectively. Age and extent of excision were independent prognostic factors for survival. Previous comparison to matched cohort receiving 60 Gy in 30 daily fractions did not demonstrate significant survival difference.

CONCLUSION

Accelerated radiotherapy is a feasible treatment approach for patients with high grade glioma. The survival and functional outcome are comparable to conventional radiotherapy and the treatment is without serious acute toxicity. While acceleration of conventional dose irradiation could be tested in randomised studies, it is unlikely this approach would result in a clinically meaningful survival benefit. Accelerated radiotherapy therefore remains one of the ways of delivering radical irradiation in patients with high grade glioma. However, it adds complexity to what is a palliative treatment regimen and the rationale and advisability should be re-examined, particularly in terms of impact on quality of life, true patient preference, and health economic considerations.

Phase I evaluation of preirradiation chemotherapy with carmustine and cisplatin and accelerated radiation therapy in patients with high-grade gliomas

OBJECTIVE

A Phase I study was conducted to determine the safety, toxicity, and maximum tolerated dose of preirradiation chemotherapy using carmustine (BCNU) and cisplatin in the treatment of high-grade gliomas.

METHODS

Patients with newly diagnosed high-grade gliomas received BCNU and cisplatin after surgery, both before and during definitive radiation therapy. Preirradiation chemotherapy consisted of an administration of 40 mg/m2 BCNU on Days 1 through 3 and 30 mg/m2 cisplatin on Days 1 through 3 and 29 through 31 and repeated at 8 weeks to coincide with the start of radiation therapy. Postradiation chemotherapy consisted of an administration of 200 mg/m2 BCNU once every 8 weeks for four cycles. Radiation therapy consisted of 160-cGy fractions administered twice daily for 15 days, yielding a total dose of 4800 cGy. Dose escalation of BCNU was planned. If hematological toxicity was mild, the dose of cisplatin was to be held constant and BCNU dose escalated to 50 mg/m2 on Days 1 through 3.

RESULTS

Eighteen patients were studied. The hematological toxicity was dose-limiting. Grade 3 or 4 leukopenia occurred in each of 10 patients (56%), and Grade 3 or 4 thrombocytopenia occurred in each of 9 patients (50%). Other toxicities included anorexia (94%), nausea (83%), emesis (33%), alopecia (94%), mild ototoxicity (50%), and, in one patient, death as a result of BCNU pulmonary toxicity. The median survival time was 14 months. Objective responses occurred in 45% of the patients evaluable for response. The maximum tolerated dose of this combination was 50 mg/m2 BCNU on Days 1 through 3 and 30 mg/m2 cisplatin on Days 1 through 3 and 29 through 31 before radiation and repeated in 8 weeks to coincide with the start of radiation.

CONCLUSION

This schedule of the preirradiation administration of BCNU and cisplatin with accelerated hyper-fractionated radiation therapy for the treatment of high-grade gliomas provides a less toxic alternative to that of previous studies of preirradiation chemotherapy with these agents and merits further investigation.

Efficacy of radiotherapy for malignant gliomas in elderly patients

PURPOSE

Age above 65 years is a strong negative prognostic factor for survival in patients with malignant gliomas (MG) treated with radiotherapy (RT) and its value has been questioned. We analyzed the effect of RT on the survival of elderly patients with malignant gliomas.

METHODS AND MATERIALS

We examined 85 consecutive elderly patients with a histological diagnosis of MG. Age ranged from 65 to 81 years (median 70 years). Glioblastoma multiforme (GBM) was diagnosed in 64 patients (75.3%). Surgical treatment included needle biopsy in 32 patients (37.6%). Median postoperative Karnofsky Performance Status (KPS) was 60 (range: 30-100). Survival probability was estimated using Kaplan-Meier method and compared with the log-rank test. Crude and adjusted hazard ratios (HR) were calculated using Cox's regression models.

RESULTS

Median survival time for all patients was 18.1 weeks. In multivariate analysis, RT was the only independent prognostic variable for survival (HR: 9.1 [95% CI: 4.5-18.7]). Forty-two patients did not start RT mostly due to low KPS (<50). The median survival of the 43 patients who started RT was 45 weeks. In these patients, Cox multivariate analysis indicated that age was independently associated with prolonged survival (HR: 2.85 [95% CI 1.31-6.19]). Median survival of patients age 70 years and younger was 55 weeks compared with 34 weeks for patients older than 70 years.

CONCLUSIONS

The overall survival for elderly patients with MG is poor. RT seems to improve survival in patients up to 70 years, but in older patients treated with RT the survival is significantly shorter.

Phase I and pharmacokinetic study of preirradiation chemotherapy with BCNU, cisplatin, etoposide, and accelerated radiation therapy in patients with high-grade glioma

PURPOSE

We conducted a Phase I study of bischloroethylnitrosourea (BCNU), cisplatin, and oral etoposide administered prior to and during accelerated hyperfractionated radiation therapy in newly diagnosed high-grade glioma. Pharmacokinetic studies of oral etoposide were also done.

METHODS AND MATERIALS

Patients started chemotherapy after surgery but prior to definitive radiation therapy (160 cGy twice daily x 15 days; 4800 cGy total). Initial chemotherapy consisted of BCNU 40 mg/m2 days 1-3, cisplatin 30 mg/m2 days 1-3 and 29-31, and etoposide 50 mg orally days 1-14 and 29-42, repeated in 8 weeks concurrent with radiation therapy. BCNU 200 mg/m2 every 8 weeks x 4 cycles was given after radiation therapy.

RESULTS

Sixteen patients, 5 with grade 3 anaplastic astrocytoma and 11 with glioblastoma were studied. Grade 3-4 leukopenia (38%) and thrombocytopenia (31%) were dose-limiting. Other toxicities were anorexia (81%), nausea (94%), emesis (56%), alopecia (88%), and ototoxicity (38%). The maximum tolerated dose was BCNU 40 mg/m2 days 1-3, cisplatin 20 mg/m2 days 1-3 and 29-31, and oral etoposide 50 mg days 1-21 and 29-49 prior to radiation therapy and repeated in 8 weeks with the start of radiation therapy followed by BCNU 200 mg/m2 every 8 weeks for 4 cycles. Median time to progression and survival were 13 and 14 months respectively. Responses occurred in 2 of 9 (22%) patients with evaluable disease. In pharmacokinetic studies, all patients achieved plasma concentrations of >0.1 microg/ml etoposide (the in vitro radiosensitizing threshold), following a 50 mg oral dose. The mean +/- SD 2 hr and 6 hr plasma concentrations were 0.92 +/- 0.43 microg/ml and 0.36 +/- 0.12 microg/ml, respectively. Estimated duration of exposure to >0.1 microg/ml etoposide was 10-17 hr.

CONCLUSIONS

Preirradiation chemotherapy with BCNU, cisplatin, and oral etoposide with accelerated hyperfractionated radiation therapy in high-grade gliomas is feasible and merits further investigation. Sustained radiosensitizing concentrations can be achieved with low oral doses of etoposide.

Accelerated radiotherapy regimen for malignant gliomas using stereotactic concomitant boosts for dose escalation

The purpose of this pilot study was to determine the feasibility and toxicities of an accelerated treatment program by using a concomitant stereotactic radiotherapy boost given weekly during a course of standard external-beam irradiation (EBXRT) in patients with malignant gliomas. Twelve patients underwent biopsy or subtotal resection of a malignant glioma and were enrolled on the protocol, which delivered 44 Gy-EBXRT and a 12-Gy stereotactic radiotherapy boost given on 3 consecutive weeks of treatment for a total dose of 80 Gy over 33 days. Three patients with anaplastic astrocytoma and nine patients with glioblastoma multiforme had median survival times of 33 months and 16 months, respectively. All of the tumor recurrences were within or were closely adjacent to the region of high-dose irradiation. None of the patients required a treatment break, and there were no acute complications. Two patients developed seizures in the follow-up period, and four patients were diagnosed with radionecrosis at the time of the second operation. The treatment program was found to be feasible and was well tolerated, and it resulted in a rate of late complications similar to those of radiosurgery or interstitial brachytherapy.

Hyperfractionated and accelerated radiation therapy in central nervous system tumors (malignant gliomas, pediatric tumors, and brain metastases)

The authors review the main contributions of the international literature concerning the role of hyperfractionation (HF), accelerated fractionation (AF), and accelerated hyperfractionation (AHF) of the dose in radiation therapy (RT) of central nervous system tumors. Basic rationales, clinical results, acute/late toxicity, and current prospectives are summarized in three sections focusing on malignant gliomas, pediatric brainstem tumors, and brain metastases. In supratentorial malignant gliomas the superiority of AHF (0.89 Gy x 3 fractions/day; total dose 61.4 Gy) over conventional fractionation ((CF) total dose 58 Gy) was demonstrated by a randomized trial. However, the gain in median survival time was less than 6 months. No other randomized trials support the preferential choice of non-CF schedules outside clinical trials. Ongoing trials are exploring the role of AHF in combination with chemotherapy, hypoxic cell and radiosensitizing agents. As for pediatric brainstem tumors, there are no data to support the routine use of HF that should be preferably used in an investigative setting. As late sequelae have been reported in the few long-term survivors, patients should be carefully selected. Regarding brain metastases AF RT and AHF RT, with their faster treatment course, may represent a convenient alternative to CF RT for the palliation of brain metastases. In carefully selected patients with solitary brain metastases non-CF RT may be part of aggressive treatment approaches.

Short course radiotherapy is an appropriate option for most malignant glioma patients

PURPOSE

To determine whether a shortened course of radiotherapy (RT) is an appropriate treatment option for malignant glioma patients.

METHODS AND MATERIALS

Prognostic groups published by the Radiation Therapy Oncology Group (RTOG) are used to compare results for a short radiotherapy regimen with results of aggressive protocol treatment. The study group includes 219 patients treated during 1975-1993 with 51 Gy in 17 fractions. Patients were retrospectively assigned to six prognostic groups previously identified in a recursive partitioning analysis of the RTOG. The prognostic groups are based on age, histology, performance status, mental status, neurologic function, resection extent, length of symptoms, and RT dose.

RESULTS

The six RTOG prognostic groupings were significantly predictive of outcome for patients treated with this shortened regimen (log-rank, p < 0.001). The median survival for our patients by RTOG groups 1-6 were 68, 57, 22, 13, 8, and 5 months, respectively. Two-year survival results were 64, 67, 45, 8, 3, and 3%. The median and two-year survival results for each prognostic grouping were similar to the results achieved by aggressive treatment on RTOG malignant glioma trials for selected patients. Treatment toxicity was uncommon.

CONCLUSION

This shortened regimen is an appropriate treatment option for most malignant glioma patients (RTOG groups 4-6), resulting in similar survival as standard regimens with reduced patient effort and cost. Although acute side effects are acceptable and the risk of brain necrosis is low, we do not recommend this treatment to the minority of patients who have a substantial long term survival probability (RTOG groups 1-3) because long term neurocognitive assessment is lacking.

Supratentorial glioblastoma: neuroradiological findings and survival after surgery and radiotherapy

Few studies have attempted to correlate neuroimaging with outcome in patients with glioblastoma. Our aim was to evaluate the relationship between neuroradiological findings and survival in these patients. We studied 18 consecutive patients with glioblastoma who had undergone surgery and radiotherapy. We assessed the following features, using preoperative CT and/or MRI: tumour size, extent of necrotic area within the mass, extent of perifocal oedema and contrast enhancement. The mean survival was 14.2 +/- 5 months (range 6-22). The extent of radiological evidence of necrosis within the mass correlated significantly with survival time, whereas tumour size, perifocal oedema and contrast enhancement did not.

Final report of a phase I/II trial of hyperfractionated and accelerated hyperfractionated radiation therapy with carmustine for adults with supratentorial malignant gliomas. Radiation Therapy Oncology Group Study 83-02

BACKGROUND

Efforts to improve local control and survival by increasing the dose of once-daily radiation therapy beyond 70 Gray (Gy) for patients with malignant gliomas has yet been unsuccessful. Hyperfractionated radiation therapy (HF) should allow for delivery of a higher total dose without increasing normal tissue late effects, whereas accelerated hyperfractionated radiation therapy (AHF) may minimize tumor repopulation by shortening overall treatment time. The Radiation Therapy Oncology Group (RTOG) conducted a randomized Phase I/II study of escalating doses of HF and AHF either carmustine (bis-chlorethyl nitrosourea [BCNU]) fro adults with supratentorial glioblastoma multiforme (GBM) or anaplastic astrocytoma (AA). Primary study endpoints were overall survival and acute and chronic treatment-related toxicity.

METHODS

From 1983 to 1989, 786 patients with supratentorial gliomas (81% with GBM and 19% with AA) were stratified by histology, age, and performance status and randomized to receive partial brain irradiation, utilizing either HF (1.2 Gy twice daily to doses of 64.8, 72, 76.8, or 81.6 Gy) of AHF (1.6 Gy twice daily to doses of 48 or 54.4 Gy). All patients received carmustine. The distinction of pronistic factors was similar on all arms.

RESULTS

There were 747 eligible and analyzable patients among 786 enrolled patients (95%). Two patients had a Grade 5 and 65 patients had a Grade 4 chemotherapy toxicity. Two patients in the 81.6 Gy arm experienced late Grade 4 radiation toxicity and there was 1 late radiation-associated death in the 54.4 Gy arm. The rate of Grade 3 of worse radiation toxicity at 5 years, calculated by the delivered does level, was 3% in the lowest total dose arms (48 and 54.4 Gy), 4% in the intermediate dose arms (64.8 and 72 Gy), and 5% in the highest dose arms (76.8 and 81.6 Gy) (p = 0.54). Survival rates at 2 and 5 years were: 21% and 11%, and 4%, respectively, for GBM patients. There were no significant differences between the treatment arms with regard to median survival time (MST), when analyzed by the originally assigned dose. The MST for all patients varied between 10.8 months and 12.7 months (P = 0.59); between 9.6 months and 11 months for patients with GBM (P = 0.43); and between 30.4 months and 85.8 months for patients with AA (P = 0.78). Analysis of the survival rates for all patients by dose received rather than by dose assigned revealed a 14% 5-year survival rate for the lower HF doses (64.8 and 73 Gy), 11% for the higher doses (76.8 and 81.6 Gy), and 10% for the AHF doses (48 and 54.4 Gy) (P = 0.1). The subgroup a AA patients had a better MST (49.9 months) in the lower received HF doses than in the higher HF doses (34.6 months) (P = 0.35). In contrast, GM patients who received the higher HF doses had survival superior to the patients in the AHF arms (MST of 11.6 months and 10.2 months, respectively, P = 0.04).

CONCLUSIONS

The use of HF with BCNU and dose escalation up to 81.6 Gy is both feasible and tolerable, although late toxicity increases slightly with increasing dose. The best MST with the least toxicity were observed for AA in the lower received HF doses (72 and 64.8 Gy). Accordingly, 72 Gy in two 1.2 Gy fractions was used as the investigational arm of a completed Phase III trial (RTOG 90-06). In contrast, for GBM patients, longer survival times were noted in the higher received HF doses (78.6 and 81.6 Gy), suggesting the role for further dose escalation. The low toxicity rate with AHF arms suggest that further dose escalation is possible and is currently occurring in RTOG 94-11.

Central pathology review in clinical trials for patients with malignant glioma. A Report of Radiation Therapy Oncology Group 83-02

BACKGROUND

Confounding biologic factors, including histologic grade, may influence the outcome of adult patients with malignant gliomas more than may modifications in therapeutic approach. Any clinical trial design for malignant gliomas in adults must account for such biologic factors, including the accurate identification of the two histologic subgroups astrocytoma with anaplastic foci (AAF) or glioblastoma multiforme (GBM), which are associated with distinctly different survival outcomes. This paper examines the need for a central pathology review before entry of patients in cooperative group clinical trials stratified by histologic grade.

METHODS

Pathology slides from Radiation Therapy Oncology Group (RTOG) trial 83-02, a randomized Phase II study of hyperfractionated and accelerated hyperfractionated radiation therapy and carmustine for malignant gliomas, provided 747 analyzable cases, with 680 (91%) available for central pathology review. This review was performed by a single pathologist according to RTOG/Eastern Cooperative Oncology Group histopathologic criteria. The kappa statistic was used to measure agreement between the institutional and central classification of AAF and GBM. The influence of misclassification was examined using computer simulation of varying clinical trial sizes (n = 25, 50, or 200). The effect on the statistical power of trials (n = 200) with varying mixtures of AAF and GBM tumors was investigated using computer simulations.

RESULTS

Of 159 tumors classified as AAF by institutional pathology review, only 66% (105) were classified as AAF (AAF/AAF) by central review, and 54 of these cases (34%) were classified as GBM (GBM/AAF), whereas 96% (501) of 521 institutionally classified as GBM (GBM/GBM) were similarly classified by central review. Computer simulations demonstrated a 59% underestimation in the median survival (1.82 vs. 4.49 years) for trials of patients with institutionally defined AAF compared to patients with centrally defined AAF in studies of 200 patients, resulting from the addition of poor prognosis of GBM in the trial. Misclassification can also substantially reduce the statistical power of a clinical trial. In one of the simulation studies, statistical power was reduced from 65% to 14% if 50% of the patients were to receive an inaccurate histologic classification. Even greater losses in power are possible in many plausible clinical settings.

CONCLUSIONS

This examination of a central versus an institutional pathology review demonstrates a low level of agreement on AAF classification and a high level of concordance on GBM classification. The results indicate the need to adjust sample size for trials of both AAF and GBM tumors to have adequate statistical power. A central pathology review remains essential for trial entry for patients with AAF and could be omitted for trials enrolling patients with GBM only.

Radiosurgery in the initial management of malignant gliomas: survival comparison with the RTOG recursive partitioning analysis. Radiation Therapy Oncology Group

PURPOSE

To evaluate the impact of stereotactic radiosurgery on the survival of patients treated with malignant gliomas.

METHODS AND MATERIALS

A total of 115 patients from three institutions (75 from the Joint Center for Radiation Therapy, 30 from the University of Wisconsin, and 10 from the University of Florida) were treated with a combination of surgery, external beam radiation therapy, and linac-based radiosurgery as part of similar institutional protocols from March 1988 through July 1993. Patients were stratified into six prognostic classes (classes 1-6) based on the recursive partitioning analysis of multiple prognostic factors previously reported by the Radiation Therapy Oncology Group.

RESULTS

The actuarial 2-year and median survival for all patients analyzed was 45% and 96 weeks, respectively. In comparison to the results from a previously published analysis of 1578 patients entered on three Radiation Therapy Oncology Group external beam radiotherapy protocols from 1974 to 1989, those patients treated with radiosurgery had a significantly improved 2-year and median survival (p = 0.01) corresponding with a standardized mortality risk ratio of 0.51 [95% confidence interval (CI): 0.31, 0.85]. This improvement in survival was seen predominantly for the worse prognostic classes (classes 3-6). The 2-year survival for the radiosurgical patients compared with the previously reported patients was 81% vs. 76% for classes 1/2, 75% vs. 35% for class 3, 34% vs. 15% for class 4, and 21% vs. 6% for classes 5/6, respectively. Although Karnofsky performance status and prognostic class were significant on univariate analysis, only the Karnofsky score was a significant predictor of outcome on multivariate analysis. Median and 2-year survival for patients with a Karnofsky score > or = 70 was 106 weeks and 51%, respectively, as compared to 38 weeks and 0% for patients with a Karnofsky score < 70% (p = 0.001).

CONCLUSIONS

The addition of radiosurgery to conventional treatment (surgery and external beam radiotherapy) of malignant gliomas appears to improve survival when compared to historical reports. These results should be interpreted with caution because the recursive partitioning model does not completely predict the prognosis of the patients treated in the present study. Although this study suggests that radiosurgery may prolong survival in patients with malignant gliomas, the role of radiosurgery in the management of these patients remains to be defined by a prospective randomized trial.

Improving the acceptability of high-dose radiotherapy by reducing the duration of treatment: accelerated radiotherapy in high-grade glioma

Radiotherapy, although clearly beneficial in patients with high-grade glioma, is largely palliative, and a protracted course of treatment may not be the most appropriate approach in the context of limited survival. We therefore assessed the feasibility, toxicity and survival results of a short accelerated radiotherapy regimen given twice daily over a period of 3 weeks. A total of 116 patients with high-grade glioma were treated with radiotherapy in a prospective study using an accelerated fractionation regimen. The total dose of 55 Gy was given in 32-36 fractions of 1.72-1.53 Gy, twice daily 5 days a week, with a minimum 6 h interval between fractions. Toxicity was assessed using Karnofsky performance status scale and in the later part of the study with the Barthel index. Survival data were compared with a control group treated with 60 Gy in 30 daily fractions in a previous MRC study, matched for known prognostic factors. The median survival of 116 patients treated with accelerated radiotherapy was 10 months. Survival comparison of accelerated patients with matched controls treated with conventional fractionation demonstrated a hazard ratio of 1.13 (95% confidence interval 0.85-1.51; P = 0.39). Early treatment toxicity was acceptable, with only seven patients developing transient decrease in performance status. The accelerated radiotherapy regimen was logistically feasible and acceptable to patients, carers and staff. Treatment time was reduced without apparent increase in early toxicity and there was no loss of survival benefit. The effectiveness and convenience of a short accelerated regimen makes this a suitable alternative to a 6 week course of radiotherapy in patients with high-grade glioma. However, a full randomised trial comparing conventional and accelerated radiotherapy may be required as proof of equivalence.

Quality-adjusted survival analysis of malignant glioma. Patients treated with twice-daily radiation (RT) and carmustine: a report of Radiation Therapy Oncology Group (RTOG) 83-02

PURPOSE

To quantify the quality of life of malignant glioma patients treated on a randomized Phase I/II trial of twice-daily radiation therapy (RT) and carmustine, using a modified quality adjusted survival (QAS) model, and to compare the QAS among assigned treatment arms.

MATERIALS AND METHODS

The Radiation Therapy Oncology Group (RTOG) accrued 786 malignant glioma patients to a Phase I/II randomized dose escalation trial of twice-daily RT with carmustine from 1983 to 1989. Patients were randomized to one of four arms of hyperfractionated RT in 1.2 Gy twice daily (BID) fractions (64.8 Gy, 72.0 Gy, 76.8 Gy, or 81.6 Gy) or to either of two accelerated hyperfractionated RT arms in 1.6 Gy BID fractions (48.0 or 54.4 Gy). Although preliminary toxicity and survival data have been published, little information is available regarding the quality of these patients' lives during and following such therapy. QAS is a refinement of the methodology for assessing survival quality among breast cancer patients receiving adjuvant chemotherapy. The QAS method allows for inclusion of both improvement and decline in neurologic functional status. Patients were scored by the presence or absence of 15 neurologic signs and symptoms at on-study and at every follow-up. Within each category were gradations of severity, with the quality survival time (Q-TIME) adjusted according to any changes in these neurologic findings. The summation of all changes in signs and symptoms were weighted by 1/15th and incorporated into the QAS model as QAS = Q-TIME-TOX-RRX. TOX was the time spent with treatment-related toxicities, and RRX was the time spent in recovery from subsequent therapy.

RESULTS

Of 747 evaluable patients, the average QAS time was 18.5 months. The average QAS for the hyperfractionated arms of 64.8 Gy, 72.0 Gy, 76.8 Gy, and 81.6 Gy were 15.6, 20.8, 10.0, and 13.7 months, respectively. For the accelerated hyperfractionated RT arms of 48.0 and 54.4 Gy, the average QAS times were 13.1 and 13.4 months. The QAS time of the 72.0 Gy arm was significantly longer than that of all other groups, except the 64.8 Gy arm. As expected, the QAS times were strongly discriminated by both age and Karnofsky Performance Scores (KPS) (p < 0.001). Younger patients and patients with high KPS benefited most from assignment to the 72.0 Gy arm; QAS time was not significantly longer in any treatment arm among patients over age 50 or with KPS scores of 80 or less.

CONCLUSIONS

This quality-adjusted survival methodology can be successfully applied to malignant glioma patients and permits a quantitative assessment of the influence of investigational therapies on patient quality of life. This analysis confirms the potential benefit of intermediate dose (72.0 Gy) hyperfractionated RT for selected malignant glioma patients.

Brain, other central nervous system, and eye cancer

BACKGROUND

The Surveillance, Epidemiology, and End Results (SEER) Program provides population-based data for the descriptive epidemiology of cancer incidence and survival rates by age, sex, race, and time period according to site and various histologic categories.

METHODS

Relative frequencies, incidence rates, median age at diagnosis, and 5-year relative survival rates were analyzed by histologic type for microscopically confirmed primary malignant tumors of the brain, central nervous system (CNS) (except lymphomas), and eye, as well as olfactory neuroblastomas.

RESULTS

Age-specific incidence rates for astrocytoma and glioblastoma, along with those for malignant meningioma, rose with increasing age up to 70-74 years, whereas rates for ependymoma and medulloblastoma (but not oligodendroglioma) showed a peak at age 0-4 years. Age-adjusted incidence rates for astrocytomas and glioblastomas were lower for blacks compared with whites, but there was little difference for rare types of brain/CNS cancers. Age-adjusted incidence rates increased slightly from 1973-1977 to 1983-1987 for astrocytoma, with little change for other histologic types. For cases diagnosed in 1983-1987, 5-year relative survival rates varied by histologic type and were low for astrocytoma, not otherwise specified (32%), and especially low for glioblastoma (4%); there was no evidence for improvement in survival rates for these two types from 1973-1977 to 1983-1987. Age-specific rates for eye melanoma rose with increasing age (especially for males), and age-adjusted rates were higher for whites than for blacks and declined from 1973-1977 to 1983-1987 in whites. Among cases diagnosed in 1983-1987, 5-year relative survival rates were high for melanoma of the eye (79%) and retinoblastoma (96%); only for retinoblastoma was there evidence of improvement in survival rates between 1973-1977 and 1983-1987.

CONCLUSIONS

The SEER data are useful in examining the descriptive epidemiologic features, including time trends in incidence and survival rates, for primary cancers of the brain, CNS and eye. The lack of improvement in the low survival rates for some of these cancers emphasizes the remaining therapeutic challenges.

White matter changes are correlated significantly with radiation dose. Observations from a randomized dose-escalation trial for malignant glioma (Radiation Therapy Oncology Group 83-02)

BACKGROUND

A Phase I/II randomized dose-seeking trial was performed to document the severity, time course, and significance of white matter changes seen on serial imaging scans (magnetic resonance imaging, computed tomography) associated with bis-chlorethyl nitrosourea (BCNU) and hyperfractionated cranial irradiation.

METHODS

Long term survivors (> or = 18 months) were identified from a prospective randomized dose-escalation Phase I/II trial designed to evaluate twice-daily radiotherapy for supratentorial high grade malignant gliomas. All scans were reviewed by a neuroradiologist who had no information about the prescribed dose and fractionation. In the trial, patients were assigned to receive 64.8 Gy, 72.0 Gy, 76.8 Gy, or 81.4 Gy (all fractionated as 1.2 Gy twice a day [bid]), or 48.0 Gy or 54.4 Gy (both in 1.6-Gy bid fractions). Bis-chlorethyl nitrosourea was administered every 8 weeks for 1 year. Of 747 randomized patients, 177 had analyzable scans. The scans reviewed were those acquired preoperatively, immediately postoperatively, 3, 6, 12, and 18 months after radiotherapy. Radiographic endpoints included no white matter change (Grade 0), minimal patchy white matter foci (Grade 1), start of confluence of white matter disease (Grade 2), large confluent areas (Grade 3), confluence with cortical/subcortical involvement (Grade 4), leukoencephalopathy (Grade 5), and possible necrosis (Grade 6) according to the classification of F. Fazekas et al. The effects were scored relative to the baseline preoperative scans. The dose pairs of 48 Gy and 54.4 Gy, 64.8 Gy and 72 Gy, and 76.8 Gy and 81.4 Gy were grouped together for analysis (low, intermediate, and high dose, respectively). Toxicity was analyzed in three ways: Grade 2 or worse, Grade 3 or worse, and Grade 6.

RESULTS

Grade 2 or worse changes were observed in 26.6, 27.6, and 40.4% of patients in the low, intermediate, and high dose groups, respectively. Grade 3 or worse changes were observed in 8.3, 20.0, and 36.5% of patients in the low, intermediate, and high dose groups, respectively. Grade 6 changes were observed in 1.6, 4.6, and 19.2% of patients in the low, intermediate, and high dose groups, respectively. No statistically significant differences were observed among treatment groups when toxicity was evaluated as Grade 2 or worse. For toxicity of Grade 3 or worse, an chi-square test revealed P values of 0.04 (low vs. intermediate dose), 0.09 (intermediate vs. high dose), and 0.0005 (low vs. high dose). With the endpoint of possible necrosis (Grade 6), P values were 0.21 (low vs. intermediate dose), 0.05 (intermediate vs. high dose), and 0.003 (low vs. high dose). The median time to radiographic appearance of an effect (15 months) was not influenced by total dose or fraction size.

CONCLUSIONS

A well described toxicity scale for white matter injury was applied successfully to patients with malignant glioma treated with definitive irradiation. Severe white matter changes continued to increase significantly as the total dose of hyperfractionated cranial irradiation was escalated. The time to onset of the white matter abnormalities appeared to be independent of dose. An ongoing Radiation Therapy Oncology Group study will allow correlation of white matter injury with prospective neuropsychometric testing.