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

The efficacy of hypofractionated radiotherapy (HFRT) with concurrent and adjuvant temozolomide in newly diagnosed glioblastoma: A meta-analysis

PURPOSE

The efficacy of hypofractionated radiotherapy (HFRT) in glioblastoma (GBM) without age restrictions remains unclear. The aim of this meta-analysis is to access the survival outcomes of HFRT in these patients.

METHODS

A comprehensive electronic literature search of PubMed, Web of Science and Cochrane Library was conducted up to June 1, 2020. The main evaluation data were the overall survival (OS) rate at 12 months and 24 months and the progression-free survival (PFS) rate at 6 and 12 months. The secondary evaluation data was the incidence of radionecrosis and adverse events. The study was performed using R "meta" package.

RESULTS

Eleven studies met the inclusion criteria, which totally contained 484 participants. The 12-month OS and 24-month OS rate of HFRT in GBM were 71.3% and 34.8%, while the 6-month PFS and 12-month rate were 74.0% and 40.8%. Compared to low-BED (biological equivalent dose) schedules (<78Gy), high-BED schedules may increase survival benefit both in PFS-6 (P=0.003) and PFS-12 (P=0.011), while the difference did not show on OS. Different dose per fraction had no significant effect on both OS and PFS. Incidence of radionecrosis was 14.2%. Although the overall incidence of adverse reactions cannot be quantified, the toxicity of HFRT was acceptable.

CONCLUSIONS

Compared with survival data for standard treatment, HFRT seemed to improve overall survival and progression-free survival, while high BED schedules may future increase benefit on PFS. Meanwhile, the toxicity of HFRT was tolerable. Further randomised controlled clinical studies are needed to confirm these findings.

Efficacy and Safety of Hypofractionated Radiotherapy for the Treatment of Newly Diagnosed Glioblastoma Multiforme: A Systematic Review and Meta-Analysis

Background: Hypofractionated radiotherapy (HFR) is sometimes used in the treatment of glioblastoma multiforme (GBM). The efficacy and safety of HFR is still under investigation. The aim of this systematic review and meta-analysis was to provide a comprehensive summary of the efficacy and safety of HFR, and to compare the efficacy and safety of HFR and conventional fraction radiotherapy (CFR) for the treatment of patients with GBM, based on the results of randomized controlled trials (RCTs).

Methods: A literature search was conducted to identify Phase II and III trials o comparing the efficacy and safety of HFR and CFR. Study selection, data extraction, and quality assessment, were conducted by two independent researchers. The analysis was performed using RevMan 5.3 and Stata 12.0.

Results: Sixteen Phase II and III trials were included in the systematic review, and four RCTs were included in the meta-analysis. Participants treated with HRF and CRF had comparable overall survival (OS) (hazard ratio [HR]: 0.94, 95% confidence interval [CI]: 0.72–1.22, P = 0.64) and progression-free survival (PFS) (HR: 1.09, 95% CI: 0.60–1.95, P = 0.79), and similar rates of adverse events. However, in participants aged >70 years, those who received HFR had a higher OS than those who received CFR (HR: 0.59, 95% CI: 0.37–0.93, P = 0.02).

Conclusions: HRF is efficacious and safe for the treatment of GBM. In individuals aged >70 years, treatment with HRF is superior to CFR in terms of OS. The role of HFR in the treatment of GBM in younger individuals and those with good prognostic factors requires further research.

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.

Irradiation Fields and Doses in Glioblastoma Multiforme: Are Current Standards Adequate?

Aims and background

The optimum conventional radiotherapy in glioblastoma multiforme patients has not been clearly defined by prospective trials. To better characterize a standard radiotherapy in glioblastoma multiforme, the impact on survival of different fields and doses was analyzed in a retrospective single center series.

Methods

One hundred and forty-seven patients with glioblastoma multiforme, submitted to biopsy only (n = 15), subtotal (n = 48) or total resection (n = 82) and who completed the planned postsurgical radiotherapy, were considered. The median age was 57 years, the male/female ratio 1.5/1, and the performance status ≥70 in 76%. Whole brain irradiation, followed by a boost to partial brain, was used in 75 cases with a whole brain dose of 44–50 Gy (median, 46) and a partial brain dose of 56–70 Gy (median, 60 Gy). Partial brain irradiation alone was used in 72 patients with a dose of 56–70 Gy (median, 61 Gy). Ninety-eight patients received 56–60 Gy (median, 59 Gy) to partial brain whereas 49 patients received 61–70 Gy (median, 63 Gy).

Results

There was an almost significantly longer survival in patients irradiated to the partial brain alone with respect to those also receiving whole brain radiotherapy (P = 0.056). Doses <60 Gy significantly prolonged survival (P = 0.006). Multivariate analysis confirmed that the impact on survival of radiation dose was independent of age, performance status, extent of surgery, field of irradiation and the use of chemotherapy. The extent of irradiation field was not independently related to improved survival.

Conclusions

Our retrospective findings suggest that we reflect on the adequacy of the current standard irradiation parameters. Well-designed prospective trials are necessary to standardize the radiotherapy control group in patients with glioblastoma multiforme to be compared in phase III trials with innovative therapeutic approaches.

Hypofractionated radiotherapy with simultaneous integrated boost (SIB) plus temozolomide in good prognosis patients with glioblastoma: a multicenter phase II study by the Brain Study Group of the Italian Association of Radiation Oncology (AIRO)

INTRODUCTION

A multicenter phase II study for assessing the efficacy and the toxicity of hypofractionated radiotherapy with SIB plus temozolomide in patients with glioblastoma was carried out by the Brain Study Group of the Italian Association of Radiation Oncology.

METHODS

Twenty-four patients with newly diagnosed glioblastoma belonging to Recursive Partitioning Analysis classes III and IV were enrolled. The prescribed dose was 52.5 Gy in 15 fractions of 3.5 Gy and 67.5 in 15 fractions of 4.5 Gy to the SIB volume. Dose constraints for the hypofractionated schedule were provided. Radiotherapy was associated with concomitant and sequential temozolomide.

RESULTS

Median overall survival (OS) was 15.1 months, while median progression-free survival (PFS) was 8.6 months. Actuarial OS at 12 months was 65.6% ± 0.09, whereas actuarial PFS at 12 months was 41.2% ± 0.10. Status of methylation of MGMT promoter resulted to be a significant prognostic factor for OS. Radiotherapy-related acute toxicity was not relevant. Three patients (12.5%) had G3 myelotoxicity that required temozolomide temporary interruption or dose reduction during the chemotherapy. However, chemotherapy was not definitely discontinued for toxicity in any case. One patient out of 24 (4.2%) developed radionecrosis that required surgical resection with no evidence of disease in the surgical specimen.

CONCLUSIONS

This trial confirms that hypofractionated radiotherapy with SIB and association with temozolomide may be a reasonable and feasible option for good prognosis patients with GBM.

Phase 1/2 Trial of 5-Fraction Stereotactic Radiosurgery With 5-mm Margins With Concurrent and Adjuvant Temozolomide in Newly Diagnosed Supratentorial Glioblastoma: Health-Related Quality of Life Results

PURPOSE

We report a longitudinal assessment of health-related quality of life (HRQOL) in patients with glioblastoma (GBM) treated on a prospective dose escalation trial of 5-fraction stereotactic radiosurgery (25-40 Gy in 5 fractions) with concurrent and adjuvant temozolomide.

METHODS

HRQOL was assessed using the European Organization for Research and Treatment of Cancer (EORTC) quality of life questionnaire core-30 (QLQ-C30) general, the EORTC quality of life questionnaire-brain cancer specific module (QLQ-BN20), and the M.D. Anderson Symptom Inventory-Brain Tumor (MDASI-BT). Questionnaires were completed at baseline and at every follow-up visit after completion of radiosurgery. Changes from baseline for 9 predefined HRQOL measures (global quality of life, physical functioning, social functioning, emotional functioning, motor dysfunction, communication deficit, fatigue, insomnia, and future uncertainty) were calculated at every time point.

RESULTS

With a median follow-up time of 10.4 months (range, 0.4-52 months), 139 total HRQOL questionnaires were completed by the 30 patients on trial. Compliance with HRQOL assessment was 76% at 12 months. Communication deficit significantly worsened over time, with a decline of 1.7 points per month (P=.008). No significant changes over time were detected in the other 8 scales of our primary analysis, including global quality of life. Although 8 patients (27%) experienced adverse radiation effects (ARE) on this dose escalation trial, it was not associated with a statistically significant decline in any of the primary HRQOL scales. Disease progression was associated with communication deficit, with patients experiencing an average worsening of 13.9 points per month after progression compared with 0.7 points per month before progression (P=.01).

CONCLUSION

On this 5-fraction dose escalation protocol for newly diagnosed GBM, overall HRQOL remained stable and appears similar to historical controls of 30 fractions of radiation therapy. Tumor recurrence was associated with worsening communication deficit, and ARE did not correlate with a decline in HRQOL.

Evaluation of outcome and prognostic factors in patients of glioblastoma multiforme: A single institution experience

Aims:

We present retrospective analysis of patients of glioblastoma multiforme (GBM) and discuss clinical characteristics, various treatment protocols, survival outcomes, and prognostic factors influencing survival.

Materials and Methods:

From January 2002 to June 2009, 439 patients of GBM were registered in our department. The median age of patients was 50 years, 66.1% were males, and 75% underwent complete or near-total excision. We evaluated those 360 patients who received radiotherapy (RT). Radiotherapy schedule was selected depending upon pre-RT Karnofsky Performance Status (KPS). Patients with KPS < 70 (Group I, n = 48) were planned for RT dose of 30-35 Gy in 10-15 fractions, and patients with KPS ≥ 70 (Group II, n = 312) were planned for 60 Gy in 30 fractions. In group I, six patients and in group II, 89 patients received some form of chemotherapy (lomustine or temozolomide).

Statistical Analysis Used:

Statistical analysis was done using Statistical Package for Social Sciences, version 12.0. Overall survival (OS) was calculated using Kaplan-Meier method, and prognostic factors were determined by log rank test. The Cox proportional hazards model was used for multivariate analysis.

Results:

The median follow-up was 7.53 months. The median and 2-year survival rates were 6.33 months and 2.24% for group I and 7.97 months and 8.21% for group II patients, respectively (P = 0.001). In multivariate analysis, site of tumor (central vs. others; P = 0.006), location of tumor (parietal lobe vs. others; P = 0.003), RT dose (<60 Gy vs. 60 Gy; P = 0.0001), and use of some form of chemotherapy (P = 0.0001) were independent prognostic factors for survival.

Conclusions:

In patients with GBM, OS and prognosis remains dismal. Whenever possible, we should use concurrent and/or adjuvant chemotherapy to maximize the benefits of post-operative radiotherapy. Patients with poor performance status may be considered for hypofractionated RT schedules, which have similar median survival rates as conventional RT.

Hypo-fractionated IMRT for patients with newly diagnosed glioblastoma multiforme: a 6 year single institutional experience

OBJECTIVES

Glioblastoma (GBM) is the most common malignant primary brain tumour in adults. Surgery and radiotherapy constitute the cornerstones for the therapeutic management of GBM. The standard treatment today is maximal surgical resection followed by concomitant chemo-radiation therapy followed by adjuvant TMZ according to Stupp protocol. Despite the progress in neurosurgery, radiotherapy and oncology, the prognosis still results poor. In order to reduce the long time of standard treatment, maintaining or improving the clinical results, in our institute we have investigated the effects of hypo-fractionated radiation therapy for patients with GBM.

PATIENTS AND METHODS

Sixty-seven patients affected by GBM who had previously undergone surgical resection (total, subtotal or biopsy) were enrolled between October 2005 and December 2011 in a single institutional study of hypo-fractionated intensity modulated radiation therapy (IMRT) followed or not by adjuvant chemotherapy with TMZ (6-12 cycles). The most important eligibility criteria were: biopsy-proven GBM, KPS ≥ 60, age ≥ 18 years, no previous brain irradiation, informed consensus. Hypo-fractionated IMRT was delivered to a total dose of 25 Gy in 5 fractions prescribed to 70% isodose. Response to treatment, OS, PFS, toxicity and patterns of recurrence were evaluated, and sex, age, type of surgery, Karnofsky performance status, Recursive Partitioning Analysis (RPA) classification, time between surgery and initiation of radiotherapy were evaluated as potential prognostic factors for survival.

RESULTS

All patients have completed the treatment protocol. Median age was 64.5 years (range 41-82 years) with 31 females (46%) and 36 males (54%). Median KPS at time of treatment was 80. The surgery was gross total in 38 patients and subtotal in 14 patients; 15 patients underwent only biopsy. No grade 3-4 acute or late neurotoxicity was observed. With median follow-up of 14.9 months, the median OS and PFS were 13.4 and 7.9 months, respectively.

CONCLUSIONS

The hypo-fractionated radiation therapy can be used for patients with GBM, resulting in favourable overall survival, low rates of toxicity and satisfying QoL. Future investigations are needed to determine the optimal fractionation for GBM.

Hypofractionated radiotherapy for glioblastoma: strategy for poor-risk patients or hope for the future?

The prognosis of patients with glioblastoma (GBM) remains poor, and the use of hyperfractionation or dose escalation beyond 60 Gy has not conferred any survival benefit. More recently, hypofractionated radiotherapy (HFRT) has been employed as a novel approach for achieving dose escalation, with interesting results. We present here a systematic overview of the role and development of HFRT as a possible therapeutic strategy in patients with GBM. We searched the PubMed database for studies published since 1990 that reported on the tolerance, safety and survival outcomes after HFRT. These studies reported on the paradox of improved survival in patients developing central radionecrosis within the high-dose volume. Most series reported no significant increase in early or late toxicity, except for one study that reported visual loss in one patient at 7 months after treatment. More recently, studies of HFRT combined with concurrent temozolomide (TMZ) reported a trend towards improved survival compared with historical controls, with a few studies reporting a median survival of approximately 20 months. The interpretation of data from the above studies is limited by the heterogeneities of patient population and the significant variation in the range of employed dose schedules. However, high-dose HFRT using intensity-modulated radiotherapy appears to be a safe and feasible therapeutic option. There is a suggestion of improved outcomes on combining HFRT with TMZ, which warrants further investigation in a randomised trial.

Accelerated intensity-modulated radiotherapy plus temozolomide in patients with glioblastoma: a phase I dose-escalation study (ISIDE-BT-1)

BACKGROUND

We performed a dose-escalation trial to determine the maximum tolerated dose (MTD) of intensity-modulated radiotherapy (IMRT) with standard concurrent and sequential-dose temozolomide (TMZ) in patients with glioblastoma multiforme.

METHODS

Histologically proven glioblastoma patients underwent IMRT dose escalation. IMRT was delivered over 5 weeks with the simultaneous integrated boost (SIB) technique to the two planning target volumes (PTVs) defined by adding 5-mm margin to the respective clinical target volumes (CTVs). CTV1 was the tumor bed plus the enhancing lesion with 10-mm margin; CTV2 was the area of perifocal edema with 20-mm margin. Only the PTV1 dose was escalated (planned dose escalation: 60, 62.5, 65, 67.5, 70 Gy) while the PTV2 dose remained the same (45 Gy).

RESULTS

Forty consecutive glioblastoma patients were treated. While no dose-limiting toxicity (DLT) was recorded during the dose escalation up to 67.5/2.7 Gy, two out of the first six consecutively enrolled patients on the highest dose level (70/2.8 Gy) experienced a DLT, and therefore a cohort expansion was required. 3/14 patients experienced a DLT on the highest planned dose level, and therefore the MTD was not exceeded. After a median follow-up time of 25 months no grade >2 late neurological toxicity was recorded.

CONCLUSIONS

By using a SIB IMRT technique, a radiation dose of 70 Gy in 25 fractions (biological effective dose--BED--of 92.8 Gy) can be delivered with concurrent and sequential standard dose TMZ, without unacceptable acute toxicity in patients with glioblastoma.

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.

The results of hypofractionated radiotherapy in 31 patients with high-grade gliomas

In this prospective study, we investigated the effects of hypofractionated radiotherapy for patients with high-grade gliomas. About 31 patients with glioblastoma multiforme or anaplastic astrocytoma were studied between October 2003 and December 2004. Hypofractionated radiotherapy (3 Gy/fraction/day) was delivered to a total dose of 45 Gy in 15 fractions in 10 patients (32%) who had total excision before radiotherapy and to a total dose of 54 Gy in 18 fractions in 21 patients (68%) who had subtotal excision or biopsy alone. Sex, age, type of surgery, tumor grade, Karnofsky performance status, time between surgery and initiation of radiotherapy, and total radiotherapy dose were analyzed as potential prognostic factors for survival using the univariate log-rank method. The median follow-up was 15 months (4-16 months). A total of 15 patients (48%) died of their illness; 16 patients (52%) were still alive at the last follow-up. The median survival time was 8 months. Actuarial 1-year overall survival was 40%. Type of surgery, timing of radiotherapy after surgery, and initial Karnofsky performance status were significant prognostic factors for survival. No grade 3-4 acute or late neurotoxicity was observed. The tolerance of patients to hypofractionated RT was not different from that for conventional radiotherapy. This treatment schedule can be used for patients with high-grade gliomas. Future investigations are needed to determine the optimal fractionation for high-grade gliomas.

Patterns of practice and survival in a retrospective analysis of 1722 adult astrocytoma patients treated between 1985 and 2001 in 12 Italian radiation oncology centers

PURPOSE

To analyze the patterns of practice and survival in a series of 1722 adult astrocytoma patients treated in 12 Italian radiotherapy centers.

METHODS AND MATERIALS

A total of 1722 patients were treated with postoperative radiotherapy (90% World Health Organization [WHO] Grade 3-4, 62% male, 44% aged >60 years, 25% with severe neurologic deficits, 44% after gross total resection, 52% with high-dose radiotherapy, and 16% with chemotherapy). Variations in the clinical-therapeutic features in three subsequent periods (1985 through 2001) were evaluated, along with overall survival for the different subgroups.

RESULTS

The proportion of women, of older patients, of those with worse neurologic performance status (NPS), with WHO Grade 4, and with smaller tumors increased with time, as did the proportion of those treated with radical surgery, hypofractionated radiotherapy, and more sophisticated radiotherapy techniques, after staging procedures progressively became more accurate. The main prognostic factors for overall survival were age, sex, neurologic performance status, WHO grade, extent of surgery, and radiation dose.

CONCLUSIONS

Recently, broader selection criteria for radiotherapy were adopted, together with simpler techniques, smaller total doses, and larger fraction sizes for the worse prognostic categories. Younger, fit patients are treated more aggressively, more often in association with chemotherapy. Survival did not change over time. The accurate evaluation of neurologic status is therefore of utmost importance before the best treatment option for the individual patient is chosen.

Radiotherapy is effective in patients with glioblastoma multiforme with a limited prognosis and in patients above 70 years of age: a retrospective single institution analysis

BACKGROUND AND PURPOSE

To evaluate the efficacy of radiotherapy in patients with glioblastoma multiforme (GBM) with a limited prognosis and in patients older than 70 years.

PATIENTS AND METHODS

Retrospective analysis of 202 patients with GBM treated between 1990 and 2000 in a single institution. Patients (including patients >or=70 years) were assigned to RPA groups and their survival was compared with RTOG data.

RESULTS

Median survival was 8.0 months for the total group and 13.9, 10.6, 3.8, 2.1 months for RPA group III (n=17), IV (n=87), V (n=60) and VI (n=38), respectively. Median survival for patients >or=70 years was 3.6 vs. 8.1 months for 50--70 years and 11.0 months for <50. In each separate RPA group, patients >or=70 years had a similar survival compared to patients of 50--70 years. Irradiated patients (66%) survived significantly longer than non-irradiated patients: 10.6 vs. 1.9 months (P<0.0001). In RPA group V the median survival for irradiated patients was 9.4 vs. 2.1 months for non-irradiated patients. In a multivariate analysis, RT remained the only prognostic factor for survival (HR 8.9, P<0.001).

CONCLUSIONS

Prognosis for patients above 70 years of age is not different from younger patients, when analyzed for separate RPA groups. For patients with a poor prognosis (i.e. RPA group V), radiotherapy improves survival significantly.

Current management of glioblastoma multiforme

Glioblastoma multiforme is the most common primary brain tumor in adults. Despite major research efforts and progress in neuroimaging, neurosurgery, and radiation and medical oncology, the overall survival of patients with this disease has changed little over the past 30 years. Surgery and radiation therapy remain critical components in the care of patients with glioblastoma multiforme. Treatment with chemotherapy has been hampered by the apparent resistance of these tumor cells to available agents and challenges in delivering agents to the tumor cells. The blood-brain barrier can restrict entry of some agents and the effect of antiepileptic drugs inducing hepatic P450 can significantly affect the pharmacology of a wide range of antineoplastic agents. As a result, new agents and novel approaches are required. Translational research efforts should: (1) pursue a broad research agenda until productive avenues are identified; (2) quantify the delivery of novel agents to the malignant brain tumor cells; (3) determine the maximum tolerated dose (MTD) and preliminary efficacy data on novel agents before initiating combination therapies; (4) optimize trial designs; and (5) improve psychosocial and supportive care for patients with this devastating illness.

A randomized trial comparing 35Gy in ten fractions with 60Gy in 30 fractions of cerebral irradiation for glioblastoma multiforme and older patients with anaplastic astrocytoma

A randomized prospective clinical trial was conducted to compare conventional high dose radiotherapy with hypofractionated, short course radiotherapy in poor prognosis patients with high grade glioma. The primary endpoint was overall survival.

Hypofractionated radiotherapy for elderly or younger low-performance status glioblastoma patients: outcome and prognostic factors

PURPOSE

To evaluate the outcome for elderly or younger poor prognosis glioblastoma patients treated with hypofractionated radiotherapy (HypoRT).

METHODS AND MATERIALS

Retrospective review at The University of Texas M. D. Anderson Cancer Center identified 59 glioblastoma patients (median age 65 years) treated with HypoRT between 1988 and 2001 with 50 Gy given at 2.5 Gy/fraction/day in 20 fractions within 4 weeks. Classification was according to the Radiation Therapy Oncology Group recursive partitioning analysis and was Class IV in 11, V in 29, and VI in 19. Surgery consisted of gross total resection (n = 16), subtotal resection (n = 28), and biopsy only (n = 13). Two patients were treated presumptively on the basis of radiographic findings. Chemotherapy was given either as part of the initial treatment (n = 15) or for progression (n = 9).

RESULTS

The median survival time for the entire study population was 7 months, and the median progression-free survival was 3.9 months. The median survival time for patients with Class IV, V, and VI was 11, 7, and 5 months, respectively. Concordance was found with Radiation Therapy Oncology Group-established recursive partitioning analysis class survival. Steroid requirements were not increased during RT compared with preoperatively and immediately postoperatively. Late complications of HypoRT were limited to 3 cases of radiation necrosis suggested by MRI, 2 of which were pathologically confirmed.

CONCLUSION

HypoRT consisting of 50 Gy in 4 weeks can be used for selected GBM patients to reduce the overall treatment time of conventional RT by 33-39% without apparent increased toxicity or decrement in survival.

Hypofractionated radiotherapy for poor prognosis malignant glioma: matched pair survival analysis with MRC controls

PURPOSE

To assess the survival benefit of palliative hypofractionated radiotherapy in patients with poor prognosis high grade glioma by a matched comparison to conventionally treated controls.

METHOD

Ninety-two elderly and/or disabled patients with high grade glioma with poor prognostic features received palliative partial brain radiotherapy to a dose of 30Gy in six fractions over 2 weeks. Patients were matched for WHO histological grade, performance status and age from a cohort of patients treated with conventionally fractionated radiotherapy to a dose of 60Gy in 30 fractions in an Medical Research Council (MRC) BR05 trial.

RESULTS

Patients treated with hypofractionated radiotherapy had a median survival of 5 months with a 1-year survival rate of 12% from diagnosis. The median survival of case-matched controls was estimated to be 2.5-4.5 months longer. Following hypofractionated radiotherapy, Barthel score was improved or remained stable in 68% of patients.

CONCLUSION

Hypofractionated partial brain radiotherapy is a well-tolerated regimen with palliative benefit. Comparison with matched controls suggests lesser survival benefit than would be obtained with radical radiotherapy. However, this is compensated by lower intensity and duration of irradiation induced side effects. It is postulated that there may not be a significant difference in good quality survival or 'quality adjusted survival' between the two regimens and this requires testing in prospective trials.

Poor-prognosis high-grade gliomas: evolving an evidence-based standard of care

Patients with high-grade glioma (HGG) can be classified as having a favourable prognosis (younger or with good performance status) or a poor prognosis (older or with poor performance status) with median survival of 12-24 months and 6-9 months, respectively. The standard management for the favourable subgroup is maximum safe resection followed by adjuvant conventionally fractionated radio therapy, with or without chemotherapy. However, most patients with HGG have a poor prognosis and their optimum management has yet to be defined. In the poor-prognosis HGG subgroup, short-course radiotherapy is equivalent to conventional radiotherapy in terms of survival and palliation (level II evidence), but chemotherapy is not recommend ed (level II evidence). The problems with the existing systems of prognosis are discussed and a pragmatic system proposed. Owing to lack of any level I evidence, the need to conduct prospective randomised trials with quality of life and palliative effect as primary endpoints is emphasised. Until such time, maximum safe resection followed by a short course of focal radiotherapy is recommended as the standard of care in poor prognosis HGG.

Radiotherapy for newly diagnosed malignant glioma in adults: a systematic review

PURPOSE

A systematic review was conducted to develop guidelines for radiotherapy in adult patients with newly diagnosed malignant glioma.

METHODS

MEDLINE, CANCERLIT, the Cochrane Library, and relevant conference proceedings were searched to identify randomized trials and meta-analyses.

RESULTS

Pooling of six randomized trials detected a significant survival benefit favouring post-operative radiotherapy compared with no radiotherapy (risk ratio, 0.81; 95% confidence interval, 0.74 to 0.88, P<0.00001). Two randomized trials demonstrated no significant difference in survival rates for whole brain radiation versus more local fields that encompass the enhancing primary plus a 2 cm margin. A randomized trial detected a small improvement in survival with 60 Gy in 30 fractions over 45 Gy in 20 fractions. Radiation dose intensification and radiation sensitizer approaches have not demonstrated superior survival rates compared with conventionally fractionated doses of 50-60 Gy.

CONCLUSIONS

Post-operative external beam radiotherapy is recommended as standard therapy for patients with malignant glioma. The high-dose volume should incorporate the enhancing tumour plus a limited margin (e.g. 2 cm) for the planning target volume, and the total dose delivered should be in the range of 50-60 Gy in fraction sizes of 1.8-2.0 Gy. Radiation dose intensification and radiation sensitizer approaches are not recommended as standard care. For patients older than age 70, preliminary data suggest that the same survival benefit can be achieved with less morbidity using a shorter course of radiotherapy. Supportive care alone is a reasonable therapeutic option in patients older than age 70 with a poor performance status.

Modelling normal tissue isoeffect distribution in conformal radiotherapy of glioblastoma provides an alternative dose escalation pattern through hypofractionation without reducing the total dose

The purpose of this study was to prove that by using conformal external beam radiotherapy (RT) normal brain structures can be protected even when applying an alternative approach of biological dose escalation: hypofractionation (HOF) without total dose reduction (TDR). Traditional 2-dimensional (2D) and conformal 3-dimensional (3D) treatment plans were prepared for 10 gliomas representing the subanatomical sites of the supratentorial brain. Isoeffect distributions were generated by the biologically effective dose (BED) formula to analyse the effect of conventionally fractionated (CF) and HOF schedules on both the spatial biological dose distribution and biological dose-volume histograms. A comparison was made between 2D-CF (2.0 Gy/day) and 3D-HOF (2.5 Gy/day) regimens, applying the same 60 Gy total doses. Integral biologically effective dose (IBED) and volumes received biologically equivalent to a dose of 54 Gy or more (V-BED54) were calculated for the lower and upper brain stem as organs of risk. The IBED values were lower with the 3D-HOF than with the 2D-CF schedule in each tumour location, means 22.7+/-17.1 and 40.4+/-16.9 in Gy, respectively (p < 0.0001). The V-BED54 values were also smaller or equal in 90% of the cases favouring the 3D-HOF scheme. The means were 2.7+/-4.8 ccm for 3D-HOF and 10.7+/-12.7 ccm for 2D-CF (p = 0.0006). Our results suggest that with conformal RT, fraction size can gradually be increased. HOF radiotherapy regimens without TDR shorten the treatment time and seem to be an alternative way of dose escalation in the treatment of glioblastoma.

The treatment of malignant cerebral tumours

Malignant cerebral tumours are uncommon. While a large proportion are resistant to conventional therapies there are a significant number of curable malignant brain tumours that require recognition and appropriate therapy.

Hypofractionation in glioblastoma multiforme

PURPOSE

To compare conventional fractionation with hypofractionation in patients with a glioblastoma multiforme. Endpoints of the analysis are overall survival and palliative effect.

MATERIALS AND METHODS

From 1988 to 1998, 155 patients with pathologically confirmed glioblastoma multiforme were prospectively analysed. Patients without irradiation and patients receiving an interstitial boost were excluded from this analysis. Three different radiation schemes were used in subsequent periods; 33x2, 8x5 and 4x7 Gy. In the last 5 years a scheme of 4x7 Gy conformal irradiation was given to poor prognosis patients. The more favourable group received the conventionally fractionated scheme up to 66 Gy.

RESULTS

Median survival was 7, 5.6 and 6.6 months for the 33x2, 8x5 and 4x7 Gy, respectively. In general, patients in the hypofractionation group had far worse prognostic factors compared with patients treated with the conventional scheme. The period of neurological improvement or stabilisation was similar between the 4x7 and 33x2 Gy group.

CONCLUSION

An extreme hypofractionation scheme of 4x7 Gy conformal irradiation in poor prognostic glioblastoma patients is well tolerated, convenient for the patient and provides equal palliation without negative effects on survival compared with conventional fractionation.

Short-course radiotherapy in elderly and frail patients with glioblastoma multiforme. A phase II study

PURPOSE

To evaluate efficacy of short-course radiotherapy (RT) in elderly (> or = 60 years) and frail [Karnofsky performance status (KPS) 50-70] patients with glioblastoma multiforme (GBM).

MATERIALS AND METHODS

Between January 1987 and June 1993, a total of 47 elderly and frail patients with histological diagnosis of GBM entered into a phase II study. RT alone was administered with tumor dose of 45 Gy in 15 daily fractions in 15 treatment days in 3 weeks to a target volume described as tumor visible on CT scan and a 2-cm margin.

RESULTS

Forty-four patients were evaluable for this analysis. There were 15 (34%) CR and 11 (25%) PR, making the overall response rate of 60%. Median duration of response was 9 months (range, 2-36 months). Improvement in pretreatment performance status was observed in 20/44 (45%) patients, 5 of which improved their KPS for 20%. Median survival time is 9 months, and 1-4 year survival rates are 39%, 6.8%, 4.5%, and 0, respectively, while median time to tumor progression is 8 months, and 1-4 year progression-free survival rates are 30%, 4.5%, 4.5%, and 0, respectively. Females did significantly better than males, patients with KPS 60-70 did significantly better than those with KPS 50, patients having tumors 4-5 cm did significantly better than those with tumors 6-8 cm as well as did those with more radical surgery when compared to those with biopsy only. On multivariate analysis, only tumor size and extent of surgery were found to independently influence survival. Acute toxicity was generally assessed as mild. One of the 12 (8%) autopsied patients had RT-induced brain necrosis.

CONCLUSION

This shortened RT appears to be an effective tool in palliation of elderly and frail patients with GBM. Further studies with more patients are needed before testing it against more aggressive treatment approaches in this patient population.

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.

Outcome in elderly patients undergoing definitive surgery and radiation therapy for supratentorial glioblastoma multiforme at a tertiary care institution

PURPOSE

To determine the efficacy of definitive surgery and radiation in patients aged 70 years and older with supratentorial glioblastoma multiforme.

METHODS AND MATERIALS

We selected elderly patients (> or = 70 years) who had primary treatment for glioblastoma multiforme at our tertiary care institution from 1977 through 1996. The study group (n = 102) included 58 patients treated with definitive radiation, 19 treated with palliative radiation, and 25 who received no radiation. To compare our results with published findings, we grouped our patients according to the applicable prognostic categories developed by the Radiation Therapy Oncology Group (RTOG): RTOG group IV (n = 6), V (n = 70), and VI (n = 26). Patients were retrospectively assigned to prognostic group IV, V, or VI based on age, performance status, extent of surgery, mental status, neurologic function, and radiation dose. Treatment included surgical resection and radiation (n = 49), biopsy alone (n = 25), and biopsy followed by radiation (n = 28). Patients were also stratified according to whether they were optimally treated (gross total or subtotal resection with postoperative definitive radiation) or suboptimally treated (biopsy, biopsy + radiation, surgery alone, or surgery + palliative radiation). Patients were considered to have a favorable prognosis (n = 39) if they were optimally treated and had a Karnofsky Performance Status (KPS) score of at least 70.

RESULTS

The median survival for patients according to RTOG groups IV, V, and VI was 9.2, 6.6, and 3.1 months, respectively (log-rank, p < 0.0004). The median overall survival was 5.3 months. The definitive radiation group (n = 58) had a median survival of 7.3 months compared to 4.5 months in the palliative radiation group (n = 19) and 1.2 months in the biopsy-alone group (p < 0.0001). Optimally treated patients had a median survival of 7.4 months compared to 2.4 months in those suboptimally treated (p < 0.0001). The favorable prognosis group had an 8.4-month median survival compared to 2.4 months in the unfavorable group (p < 0.0001). On multivariate analysis, the KPS, RTOG group, favorable/unfavorable prognosis, and optimal treatment/suboptimal treatment were significant predictors of survival.

CONCLUSION

Elderly patients with good performance status (> or = 70 KPS) when treated aggressively with maximal resection and definitive radiation had longer survival than those treated with palliative radiation and biopsy. Aggressive treatment in such patients should be considered.