Biopsy versus resection for malignant glioma

Updates on management of gliomas in the molecular age

Gliomas are primary brain tumors derived from glial cells of the central nervous system, afflicting both adults and children with distinct characteristics and therapeutic challenges. Recent developments have ushered in novel clinical and molecular prognostic factors, reshaping treatment paradigms based on classification and grading, determined by histological attributes and cellular lineage. This review article delves into the diverse treatment modalities tailored to the specific grades and molecular classifications of gliomas that are currently being discussed and used clinically in the year 2023. For adults, the therapeutic triad typically consists of surgical resection, chemotherapy, and radiotherapy. In contrast, pediatric gliomas, due to their diversity, require a more tailored approach. Although complete tumor excision can be curative based on the location and grade of the glioma, certain non-resectable cases demand a chemotherapy approach usually involving, vincristine and carboplatin. Additionally, if surgery or chemotherapy strategies are unsuccessful, Vinblastine can be used. Despite recent advancements in treatment methodologies, there remains a need of exploration in the literature, particularly concerning the efficacy of treatment regimens for isocitrate dehydrogenase type mutant astrocytomas and fine-tuned therapeutic approaches tailored for pediatric cohorts. This review article explores into the therapeutic modalities employed for both adult and pediatric gliomas in the context of their molecular classification.

The fence post depth electrode technique to control both brain tumors and epileptic seizures in patients with brain tumor-related epilepsy

Background:

To control brain tumor-related epilepsy (BTRE), both epileptological and neuro-oncological approaches are required. We hypothesized that using depth electrodes (DEs) as fence post catheters, we could detect the area of epileptic seizure onset and achieve both brain tumor removal and epileptic seizure control.

Methods:

Between August 2009 and April 2018, we performed brain tumor removal for 27 patients with BTRE. Patients who underwent lesionectomy without DEs were classified into Group 1 (13 patients) and patients who underwent the fence post DE technique were classified into Group 2 (14 patients).

Results:

The patients were 15 women and 12 men (mean age, 28.1 years; median age 21 years; range, 5–68 years). The brain tumor was resected to a greater extent in Group 2 than Group 1 (P < 0.001). Shallower contacts showed more epileptogenicity than deeper contacts (P < 0.001). Group 2 showed better epilepsy surgical outcomes than Group 1 (P = 0.041).

Conclusion:

Using DEs as fence post catheters, we detected the area of epileptic seizure onset and controlled epileptic seizures. Simultaneously, we removed the brain tumor to a greater extent with fence post DEs than without.

Glioblastoma in Elderly Patients: Current Management and Future Perspectives

The incidence of glioblastoma (GBM) in the elderly population is slowly increasing in Western countries. Current management includes surgery, radiation therapy (RT) and chemotherapy; however, survival is significantly worse than that observed in younger patients and the optimal treatment in terms of efficacy and safety remains a matter of debate. Surgical resection is often employed as initial treatment for elderly patients with GBM, although the survival benefit is modest. Better survival has been reported in elderly patients treated with RT compared with those receiving supportive care alone, with similar survival outcome for patients undergoing standard RT (60 Gy over 6 weeks) and hypofractionated RT (25⁻40 Gy in 5⁻15 daily fractions). Temozolomide, an alkylating agent, may represent an effective and safe therapy in patients with promoter methylation of O⁶-methylguanine-DNA-methyltransferase (MGMT) gene which is predictor of responsiveness to alkylating agents. An abbreviated course of RT, 40 Gy in 15 daily fractions in combination with adjuvant and concomitant temozolomide has emerged as an effective treatment for patients aged 65 years old or over with GBM. Results of the National Cancer Institute of Canada Clinical Trials Group (NCIC CTG CE6) and European Organization for Research and Treatment of Cancer (EORTC 26062/22061) randomized study of short-course RT with or without concurrent and adjuvant temozolomide have demonstrated a significant improvement in progression-free survival and overall survival for patients receiving RT and temozolomide over RT alone, without impairing either quality of life or functional status. Although combined chemoradiation has become the recommended treatment in fit elderly patients with GBM, several questions remain unanswered, including the survival impact of chemoradiation in patients with impaired neurological status, advanced age (>75⁻80 years old), or for those with severe comorbidities. In addition, the efficacy and safety of alternative therapeutic approaches according to the methylation status of the O⁶-methylguanine-DNA methyl-transferase (MGMT) gene promoter need to be explored in future trials.

Intraoperative imaging technology to maximise extent of resection for glioma

BACKGROUND

Extent of resection is considered to be a prognostic factor in neuro-oncology. Intraoperative imaging technologies are designed to help achieve this goal. It is not clear whether any of these sometimes very expensive tools (or their combination) should be recommended as standard care for people with brain tumours. We set out to determine if intraoperative imaging technology offers any advantage in terms of extent of resection over standard surgery and if any one technology was more effective than another.

OBJECTIVES

To establish the overall effectiveness and safety of intraoperative imaging technology in resection of glioma. To supplement this review of effects, we also wished to identify cost analyses and economic evaluations as part of a Brief Economic Commentary (BEC).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 7, 2017), MEDLINE (1946 to June, week 4, 2017), and Embase (1980 to 2017, week 27). We searched the reference lists of all identified studies. We handsearched two journals, the Journal of Neuro-Oncology and Neuro-oncology, from 1991 to 2017, including all conference abstracts. We contacted neuro-oncologists, trial authors, and manufacturers regarding ongoing and unpublished trials.

SELECTION CRITERIA

Randomised controlled trials evaluating people of all ages with presumed new or recurrent glial tumours (of any location or histology) from clinical examination and imaging (computed tomography (CT) or magnetic resonance imaging (MRI), or both). Additional imaging modalities (e.g. positron emission tomography, magnetic resonance spectroscopy) were not mandatory. Interventions included intraoperative MRI (iMRI), fluorescence-guided surgery, ultrasound, and neuronavigation (with or without additional image processing, e.g. tractography).

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the search results for relevance, undertook critical appraisal according to known guidelines, and extracted data using a prespecified pro forma.

MAIN RESULTS

We identified four randomised controlled trials, using different intraoperative imaging technologies: iMRI (2 trials including 58 and 14 participants, respectively); fluorescence-guided surgery with 5-aminolevulinic acid (5-ALA) (1 trial, 322 participants); and neuronavigation (1 trial, 45 participants). We identified one ongoing trial assessing iMRI with a planned sample size of 304 participants for which results are expected to be published around autumn 2018. We identified no trials for ultrasound.Meta-analysis was not appropriate due to differences in the tumours included (eloquent versus non-eloquent locations) and variations in the image guidance tools used in the control arms (usually selective utilisation of neuronavigation). There were significant concerns regarding risk of bias in all the included studies. All studies included people with high-grade glioma only.Extent of resection was increased in one trial of iMRI (risk ratio (RR) of incomplete resection 0.13, 95% confidence interval (CI) 0.02 to 0.96; 1 study, 49 participants; very low-quality evidence) and in the trial of 5-ALA (RR of incomplete resection 0.55, 95% CI 0.42 to 0.71; 1 study, 270 participants; low-quality evidence). The other trial assessing iMRI was stopped early after an unplanned interim analysis including 14 participants, therefore the trial provides very low-quality evidence. The trial of neuronavigation provided insufficient data to evaluate the effects on extent of resection.Reporting of adverse events was incomplete and suggestive of significant reporting bias (very low-quality evidence). Overall, reported events were low in most trials. There was no clear evidence of improvement in overall survival with 5-ALA (hazard ratio 0.83, 95% CI 0.62 to 1.07; 1 study, 270 participants; low-quality evidence). Progression-free survival data were not available in an appropriate format for analysis. Data for quality of life were only available for one study and suffered from significant attrition bias (very low-quality evidence).

AUTHORS' CONCLUSIONS

Intra-operative imaging technologies, specifically iMRI and 5-ALA, may be of benefit in maximising extent of resection in participants with high grade glioma. However, this is based on low to very low quality evidence, and is therefore very uncertain. The short- and long-term neurological effects are uncertain. Effects of image-guided surgery on overall survival, progression-free survival, and quality of life are unclear. A brief economic commentary found limited economic evidence for the equivocal use of iMRI compared with conventional surgery. In terms of costs, a non-systematic review of economic studies suggested that compared with standard surgery use of image-guided surgery has an uncertain effect on costs and that 5-aminolevulinic acid was more costly. Further research, including studies of ultrasound-guided surgery, is needed.

Intraoperative imaging technology to maximise extent of resection for glioma

This is a protocol for a Cochrane Review (Intervention). The objectives are as follows:

To establish the overall effectiveness and safety of intraoperative imaging in resection of glial tumours.

Delivery of local therapeutics to the brain: working toward advancing treatment for malignant gliomas

Malignant gliomas, including glioblastoma and anaplastic astrocytomas, are characterized by their propensity to invade surrounding brain parenchyma, making curative resection difficult. These tumors typically recur within two centimeters of the resection cavity even after gross total removal. As a result, there has been an emphasis on developing therapeutics aimed at achieving local disease control. In this review, we will summarize the current developments in the delivery of local therapeutics, namely direct injection, convection-enhanced delivery and implantation of drug-loaded polymers, as well as the application of these therapeutics in future methods including microchip drug delivery and local gene therapy.

Neurosurgical oncology: advances in operative technologies and adjuncts

Modern glioma surgery has evolved around the central tenet of safely maximizing resection. Recent surgical adjuncts have focused on increasing the maximum extent of resection while minimizing risk to functional brain. Technologies such as cortical and subcortical stimulation mapping, intraoperative magnetic resonance imaging, functional neuronavigation, navigable intraoperative ultrasound, neuroendoscopy, and fluorescence-guided resection have been developed to augment the identification of tumor while preserving brain anatomy and function. However, whether these technologies offer additional long-term benefits to glioma patients remains to be determined. Here we review advances over the past decade in operative technologies that have offered the most promising benefits for glioblastoma patients.

Image guided surgery for the resection of brain tumours

BACKGROUND

Extent of resection is believed to be a key prognostic factor in neuro-oncology. Image guided surgery uses a variety of tools or technologies to help achieve this goal. It is not clear whether any of these, sometimes very expensive, tools (or their combination) should be recommended as part of standard care for patient with brain tumours. We set out to determine if image guided surgery offers any advantage in terms of extent of resection over surgery without any image guidance and if any one tool or technology was more effective.

OBJECTIVES

To compare image guided surgery with surgery either not using any image guidance or to compare surgery using two different forms of image guidance. The primary outcome criteria was extent of resection and adverse events. Other outcome criteria were overall survival; progression free survival; and quality of life (QoL).

SEARCH METHODS

The following databases were searched, the Cochrane Central Register of Controlled Trials (CENTRAL) (Issue 1, 2013), MEDLINE (1948 to March, week 10, 2013) and EMBASE (1970 to 2013, week 10). Reference lists of all identified studies were searched. Two journals, the Journal of Neuro-Oncology and Neuro-oncology, were handsearched from 1991 to 2013, including all conference abstracts. Neuro-oncologists, trial authors and manufacturers were contacted regarding ongoing and unpublished trials.

SELECTION CRITERIA

Study participants included patients of all ages with a presumed new or recurrent brain tumour (any location or histology) from clinical examination and imaging (computed tomography (CT), magnetic resonance imaging (MRI) or both). Image guidance interventions included intra-operative MRI (iMRI); fluorescence guided surgery; neuronavigation including diffusion tensor imaging (DTI); and ultrasonography. Included studies had to be randomised controlled trials (RCTs) with comparisons made either with patients having surgery without the image guidance tool in question or with another type of image guidance tool. Subgroups were to include high grade glioma; low grade glioma; brain metastasis; skull base meningiomas; and sellar or parasellar tumours.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed the search results for relevance, undertook critical appraisal according to known guidelines, and extracted data using a pre-specified pro forma.

MAIN RESULTS

Four RCTs were identified, each using a different image guided technique: 1. iMRI (58 patients), 2. 5-aminolevulinic acid (5-ALA) fluorescence guided surgery (322 patients), 3. neuronavigation (45 patients) and 4. DTI-neuronavigation (238 patients). Meta-analysis was not appropriate due to differences in the tumours included (eloquent versus non-eloquent locations) and variations in the image guidance tools used in the control arms (usually selective utilisation of neuronavigation). There were significant concerns regarding risk of bias in all the included studies, especially for the study using DTI-neuronavigation. All studies included patients with high grade glioma, with one study also including patients with low grade glioma. The extent of resection was increased with iMRI (risk ratio (RR) (incomplete resection) 0.13, 95% CI 0.02 to 0.96, low quality evidence), 5-ALA (RR 0.55, 95% CI 0.42 to 0.71) and DTI-neuronavigation (RR 0.35, 95% CI 0.20 to 0.63, very low quality evidence). Insufficient data were available to evaluate the effects of neuronavigation on extent of resection. Reporting of adverse events was incomplete, with a suggestion of significant reporting bias. Overall, reported events were low in most studies, but there was concern that surgical resection using 5-ALA may lead to more frequent early neurological deficits. There was no clear evidence of improvement in overall survival (OS) with 5-ALA (hazard ratio (HR) 0.82, 95% CI 0.62 to 1.07) or DTI-neuronavigation (HR 0.57, 95% CI 0.32 to 1.00) in patients with high grade glioma. Progression-free survival (PFS) data were not available in the appropriate format for analysis.Data for quality of life (QoL) were only available for one study and suffered from significant attrition bias.

AUTHORS' CONCLUSIONS

There is low to very low quality evidence (according to GRADE criteria) that image guided surgery using iMRI, 5-ALA or DTI-neuronavigation increases the proportion of patients with high grade glioma that have a complete tumour resection on post-operative MRI. There is a theoretical concern that maximising the extent of resection may lead to more frequent adverse events but this was poorly reported in the included studies. Effects of image guided surgery on survival and QoL are unclear. Further research, including studies of ultrasound guided surgery, is needed.

Temozolomide for high grade glioma

BACKGROUND

High grade glioma (HGG) is an aggressive form of brain cancer. Treatment of HGG usually entails biopsy, or resection if safe, followed by radiotherapy. Temozolomide is a novel oral chemotherapy drug that penetrates into the brain and purportedly has a low incidence of adverse events.

OBJECTIVES

To assess whether temozolomide has any advantage for treating HGG in either primary or recurrent disease settings.

SEARCH METHODS

The following databases were searched: CENTRAL (Issue 10, 2012), MEDLINE, EMBASE, Science Citation Index, Physician Data Query and the Meta-Register of Controlled Trials in October, 2012. Reference lists of identified studies were searched. The Journal of Neuro-Oncology and Neuro-oncology were handsearched from 1999 to 2012 including conference abstracts. We contacted neuro-oncologists regarding ongoing and unpublished trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs) where the interventions were the use of temozolomide during primary therapy or for recurrent disease. Comparisons included no chemotherapy, non-temozolomide chemotherapy or different dosing schedules of temozolomide. Patients included those of all ages with histologically proven HGG.

DATA COLLECTION AND ANALYSIS

Two review authors undertook the quality assessment and data extraction. Outcome measures included: overall survival (OS); progression-free survival (PFS); quality of life (QoL); and adverse events.

MAIN RESULTS

For primary therapy three RCTs were identified, enrolling a total of 745 patients, that investigated temozolomide in combination with radiotherapy versus radiotherapy alone for glioblastoma multiforme (GBM). Temozolomide increased OS (hazard ratio (HR) 0.60, 95% confidence interval (CI) 0.46 to 0.79, P value 0.0003) and increased PFS (HR 0.63, 95% CI 0.43 to 0.92, P value 0.02), when compared with radiotherapy alone, although these benefits only appear to emerge when therapy is given in both concomitant and adjuvant phases of treatment. A single RCT found that temozolomide did not have a statistically significant effect on QoL. Risk of haematological complications, fatigue and infections were increased with temozolomide.In recurrent HGG, two RCTs enrolling 672 patients in total found that temozolomide did not increase OS compared to standard chemotherapy (HR 0.9, 95% CI 0.76 to 1.06, P value 0.2) but it did increase PFS in a subgroup analysis of grade IV GBM tumours (HR 0.68, 95% CI 0.51 to 0.90, P value 0.008). Adverse events were similar between arms.In the elderly, 2 RCTs of 664 patients found OS and PFS was similar with temozolomide alone versus radiotherapy alone. QoL did not appear to differ between arms in a single trial but certain adverse events were significantly more common with temozolomide.

AUTHORS' CONCLUSIONS

Temozolomide when given in both concomitant and adjuvant phases is an effective primary therapy in GBM compared to radiotherapy alone. It prolongs survival and delays progression without impacting on QoL but it does increase early adverse events. In recurrent GBM, temozolomide compared with standard chemotherapy improves time-to-progression (TTP) and may have benefits on QoL without increasing adverse events but it does not improve overall. In the elderly, temozolomide alone appears comparable to radiotherapy in terms of OS and PFS but with a higher instance of adverse events.

Vasculogenic mimicry is a prognostic factor for postoperative survival in patients with glioblastoma

A previous report has confirmed the existence and clinical significance of vasculogenic mimicry (VM) in glioma. However, its conclusions about the negative clinical significance of VM in glioblastoma are based on a small group of patients and, thus, might be unconvincing. The aim of the present study was to reevaluate the clinical significance of VM in glioblastoma. Patients were classified as VM-positive or VM-negative according to CD34 and periodic acid-Schiff staining. The association between VM and the clinical characteristics of the patients was analyzed. Univariate and multivariate analyses were carried out to identify the independent prognostic factors for overall survival using the Cox regression hazard model. Survival times were estimated using the Kaplan-Meier method and compared using the log-rank test. Of all 86 glioblastomas, 23 were found to have VM. The presence of VM in glioblastoma was not associated with gender, age, Karnofsky performance status, hydrocephalus, tumor burden, microvessel density, tumor relapse, or the extent of tumor resection. The univariate and multivariate analyses revealed that VM is an independent prognostic factor for overall survival. The median survival time for patients with VM was 11.17 months compared with 16.10 months for those without VM (P = 0.017). In addition to VM, an age of 65 years or older, a KPS of 60 or less, a large tumor burden are significant prognostic factors for patient survival. Our data suggest that VM might be an independent adverse prognostic factor in newly diagnosed GBM, further prospective studies are needed to answer this question.

Real-time multi-modality imaging of glioblastoma tumor resection and recurrence

The lack of relevant pre-clinical animal models incorporating the clinical scenario of Glioblastoma multiforme (GBM) resection and recurrence has contributed significantly to the inability to successfully treat GBM. A multi-modality imaging approach that allows real-time assessment of tumor resection during surgery and non-invasive detection of post-operative tumor volumes is urgently needed. In this study, we report the development and implementation of an optical imaging and magnetic resonance imaging (MRI) approach to guide GBM resection during surgery and track tumor recurrence at multiple resolutions in mice. Intra-operative fluorescence-guided surgery allowed real-time monitoring of intracranial tumor removal and led to greater than 90 % removal of established intracranial human GBM. The fluorescent signal clearly delineated tumor margins, residual tumor, and correlated closely with the clinically utilized fluorescence surgical marker 5-aminolevulinic acid/porphyrin. Post-operative non-invasive optical imaging and MRI confirmed near-complete tumor removal, which was further validated by immunohistochemistry (IHC). Longitudinal non-invasive imaging and IHC showed rapid recurrence of multi-focal tumors that exhibited a faster growth rate and altered blood-vessel density compared to non-resected tumors. Surgical tumor resection significantly extended long-term survival, however mice ultimately succumbed to the recurrent GBM. This multi-modality imaging approach to GBM resection and recurrence in mice should provide an important platform for investigating multiple aspects of GBM and ultimately evaluating novel therapeutics.

Imaging features of invasion and preoperative and postoperative tumor burden in previously untreated glioblastoma: Correlation with survival

BACKGROUND

A paucity of data exists concerning the prognostic usefulness of preoperative and postoperative imaging after resection of glioblastoma multiforme (GBM). This study aimed to connect outcome with imaging features of GBM.

METHODS

Retrospective computer-assisted volumetric calculations quantified central necrotic (T0), gadolinium-enhanced (T1) and increased T2-weighted signal volumes (T2) in 70 patients with untreated GBM. Clinical and treatment data, including extent of resection (EOR), were obtained through chart review. T1 volume was used as a measure of solid tumor burden; and T2 volume, as an indicator of invasive isolated tumor cell (ITC) burden. Indicators of invasiveness included T2:T1 ratios as a propensity for ITC infiltration compared to solid tumor volumes and qualitative analysis of subependymal growth and infiltration of the basal ganglia, corpus callosum or brainstem. Cox multivariate analysis (CMVA) was used to identify significant associations between imaging features and survival.

RESULTS

In the 70 patients studied, significant associations with reduced survival existed for gadolinium-enhancing tumor crossing the corpus callosum (odds ratio, 3.14) and with increased survival with gross total resection (GTR) (GTR median survival, 62 weeks versus 37 and 34 weeks for sub-total resection and biopsy, respectively). For a selected "GTR-eligible" subgroup of 52 patients, prolonged survival was associated with smaller preoperative gadolinium-enhancing volume (T1) and actual GTR.

CONCLUSION

Some magnetic resonance (MR) imaging indicators of tumor invasiveness (gadolinium-enhancing tumor crossing the corpus callosum) and tumor burden (GTR and preoperative T1 volume in GTR-eligible subgroup) correlate with survival. However, ITC-infiltrative tumor burden (T2 volume) and "propensity" for ITC invasiveness (T2:T1 ratio) did not impact survival. These results indicate that while the ITC component is the ultimate barrier to cure for GBM, the pattern of spread and volumes of gadolinium-enhancing solid tumor are more robust indicators of prognosis.

Supratentorial glioblastoma multiforme: the role of surgical resection versus biopsy among older patients

BACKGROUND

The peak incidence of glioblastoma multiforme (GBM) occurs in those aged 65 years and older. However, studies on this patient group remain limited. The goal of this study is to evaluate the efficacy of surgery versus biopsy for older patients with these lesions.

METHODS

133 and 72 consecutive patients aged 65 years and older who underwent surgery and needle biopsy for intracranial primary (de novo) GBM between 1997 and 2007 were retrospectively reviewed. Among these patients, 40 who underwent surgical resection were matched with 40 who underwent needle biopsy alone for factors consistently shown to be associated with survival [age, Karnofsky Performance Scale (KPS) indexing, eloquent involvement, radiation, temozolomide]. Survival was expressed as estimated Kaplan-Meier plots, and log-rank analysis was used to compare survival curves.

RESULTS

Mean ± standard deviation age was 73 ± 5 years, and median survival was 4.9 months. There were no significant differences in perioperative outcomes among patients who underwent surgical resection versus needle biopsy. Patients who underwent resection had median survival of 5.7 months as compared with 4.0 months for patients who underwent needle biopsy (P = 0.02). Likewise, for patients aged 70 years and older, median survival was 4.5 months for 26 patients who underwent surgical resection as compared with 3.0 months for 26 patients who underwent needle biopsy (P = 0.03).

CONCLUSION

This study demonstrates that older patients tolerate aggressive surgery without increased surgery-related morbidity and have prolonged survival as compared with similar patients undergoing needle biopsy. These findings may help guide treatment decisions for patients, their families, and their physicians.

New treatment options in the management of glioblastoma multiforme: a focus on bevacizumab

Glioblastoma multiforme (GBM) is the most common malignant primary brain tumor in adults and carries the poorest prognosis. Despite recent progress in molecular biology, neuro-imaging and neuro-surgical care, the management of patients with GBM continues to harbor significant challenges. Survival after diagnosis is poor even with the most aggressive approach using multimodality therapy. Although the etiology of malignant gliomas is not known, the dependency of tumor growth on angiogenesis has identified this pathway as a promising therapeutic target. Bevacizumab was the first antiangiogenic therapy approved for use in cancer and received accelerated Food and Drug Administration approval for the treatment of recurrent GBM in 2009, the first new drug for this disease in over a decade. This review describes the rationale behind the treatment of GBM with bevacizumab. The pharmacology, efficacy, safety and tolerability of bevacizumab will also be reviewed.

Temozolomide for high grade glioma

BACKGROUND

High grade glioma (HGG) is an aggressive form of brain tumour the treatment of which usually entails biopsy or resection where possible followed by radiotherapy. Temozolomide is a novel oral chemotherapeutic drug that penetrates into the brain and has a low incidence of adverse effects.

OBJECTIVES

To assess whether temozolomide holds any advantage over conventional therapy for HGG in either primary or recurrent disease settings.

SEARCH STRATEGY

The following databases were searched: the Cochrane Central Register of Controlled Trials (CENTRAL) Issue 2, 2007. Medline, EMBASE, Science Citation Index, Physician Data Query and the Meta-Register of Controlled Trials. Reference lists of identified studies were searched. The Journal of Neuro-Oncology was hand searched from 1999 to 2007 including conference abstracts. Neuro-oncologists were contacted regarding ongoing and unpublished trials.

SELECTION CRITERIA

Randomised controlled trials (RCTs). Interventions included the use of temozolomide during primary therapy or for recurrent disease. Patients included those of all ages with a proven pathological diagnosis of HGG.

DATA COLLECTION AND ANALYSIS

Quality assessment and data extraction were undertaken by two review authors. Outcome measures included survival, time to progression, quality of life (QOL) and adverse events.

MAIN RESULTS

In primary disease two RCTs were identified, enrolling a total of 703 patients, that investigated concomitant and adjuvant temozolomide in Glioblastoma Multiforme (GBM). Temozolomide increased survival (hazard ratio (HR) 0.84, confidence interval (CI) 0.50 to 0.68, p < 0.001) and an increase in time to progression (HR 0.52 CI 0.42 to 0.64 p < 0.0001). This was without having a statistically significant negative effect on QOL and with a low incidence of early adverse events. Grade 3/4 haematological toxicity was found in 5 to14%. The long term effects of temozolomide are still to be assessed. In recurrent GBM a single trial enrolling 225 patients in total found that temozolomide did not increase overall survival but it did increase time to progression (HR 0.68 CI 0.51 to 0.90 p0.008). Severe adverse events were low in this setting.

AUTHORS' CONCLUSIONS

Temozolomide is an effective therapy in GBM for prolonging survival and delaying progression as part of primary therapy without impacting on QoL and with a low incidence of early adverse events. The frequency and severity of late adverse events is unknown. In recurrent GBM it improves time to progression but not overall survival. These findings are from three good quality but non-blinded RCTs of over 900 patients in total.

Chemotherapeutic wafers for High Grade Glioma

BACKGROUND

Standard treatment for high grade glioma (HGG) usually entails biopsy or surgical resection where possible followed by radiotherapy. Systemic chemotherapy is usually only given in selected cases and its use is often limited by side effects. Implanting wafers impregnated with chemotherapy agents into the resection cavity represents a novel means of delivering drugs to the central nervous system (CNS) with fewer side effects. It is not clear how effective this modality is or whether it should be recommended as part of standard care for HGG.

OBJECTIVES

To assess whether chemotherapeutic wafers have any advantage over conventional therapy for HGG.

SEARCH STRATEGY

The following databases were searched: The Cochrane Central Register of Controlled Trials (CENTRAL), Issue 2, 2007, MEDLINE, EMBASE, SCIENCE CITATION INDEX, Physician Data Query and the meta-Register of Controlled Trials. Reference lists of all identified studies were searched. The Journal of Neuro-Oncology was hand searched from 1999 to 2007, including all conference abstracts. Neuro-oncologists were contacted regarding ongoing and unpublished trials.

SELECTION CRITERIA

Patients included those of all ages with a presumed diagnosis of malignant glioma from clinical examination and radiology. Interventions included insertion of chemotherapeutic wafers to the resection cavity at either primary surgery or for recurrent disease. Included studies had to be randomised controlled trials (RCTs).

DATA COLLECTION AND ANALYSIS

Quality assessment and data extraction were undertaken by two review authors. Outcome measures included survival, time to progression, quality of life (QOL) and adverse events.

MAIN RESULTS

In primary disease two RCTs assessing the effect of carmustine impregnated wafers (Gliadel(R)) and enrolling a total of 272 participants were identified. Survival was increased (hazard ratio (HR) 0.65 confidence interval (CI) 0.48 to 0.86 p = 0.003). In recurrent disease a single RCT was included assessing the effect of Gliadel(R) and enrolling 222 participants. It did not demonstrate a significant survival increase (HR 0.83 CI 0.62 to 1.10 p = 0.2). There was no suitable data for time to progression or QOL. Adverse events were not more common in either arm, and were presented in a descriptive fashion.

AUTHORS' CONCLUSIONS

Gliadel(R) results in a prolongation of survival without an increased incidence of adverse events when used as primary therapy. There is no evidence of enhanced progression free survival (PFS) or QOL. In recurrent disease, Gliadel(R) does not appear to confer any added benefit. These findings are based on the results of three RCTs with approximately 500 patients in total.

Clinical course of high-grade glioma patients with a "biopsy-only" surgical approach: a need for individualised treatment

INTRODUCTION

'Biopsy-only' high-grade glioma (HGG) patients get limited benefit from post-operative treatments, and as a group, negatively impact median survival outcomes.

MATERIAL AND METHODS

We retrospectively evaluated clinical characteristics, treatment and overall survival of HGG patients with a 'biopsy- only' surgical approach diagnosed between 1997 and 2005 at a University Hospital in Spain.

RESULTS

In 31% of 294 suspected gliomas, only a diagnostic biopsy was undertaken. Reasons for 'biopsy-only' for all patients were either location in eloquent areas: (motor area 18.7%, language area 25,3%, basal ganglia 7.7%, visual area 4.4%) or extension of the disease (corpus callosum invasion 14.3% and multicentricity/multifocality 28.6%). Seventy-four patients (80.4%) were HGG: 26% of all grade IV and 49% of all grade III tumours. For these patients, post-operative Karnofsky Performance Status of over 70%, median age and median survival were, respectively: 64 and 70%, 60.7 and 57 years old, and 23.1 and 42.7 weeks (p=0.0006). Patients lived longer if post-operative treatment was given, in all grades (p<0.0001). Nineteen patients (25.6%) died within 42 days after surgery. Only 60% of them initiated radiotherapy and 10% of them did not complete it. However, tumour grade, radiotherapy and temozolomide- based chemotherapy were independently associated with longer survival in multivariate analysis (p<0.05).

CONCLUSION

Almost one third of HGG patients can undergo only a biopsy and not debulking surgery. Although radiotherapy improves survival, only 50% of them complete the treatment. An individualised approach to these patients is needed to facilitate a correct analysis of therapy results. New therapies must be investigated in these patients.

Prognostic factors for survival in 676 consecutive patients with newly diagnosed primary glioblastoma

Reliable data on large cohorts of patients with glioblastoma are needed because such studies differ importantly from trials that have a strong bias toward the recruitment of younger patients with a higher performance status. We analyzed the outcome of 676 patients with histologically confirmed newly diagnosed glioblastoma who were treated consecutively at a single institution over a 7-year period (1997-2003) with follow-up to April 30, 2006. Survival probabilities were 57% at 1 year, 16% at 2 years, and 7% at 3 years. Progression-free survival was 15% at 1 year. Prolongation of survival was significantly associated with surgery in patients with a good performance status, whatever the patient's age, with an adjusted hazard ratio of 0.55 (p < 0.001) or a 45% relative decrease in the risk of death. Radiotherapy and chemotherapy improved survival, with adjusted hazard ratios of 0.61 (p = 0.001) and 0.89 (p = 0.04), respectively, regardless of age, performance status, or residual tumor volume. Recurrence occurred in 99% of patients throughout the follow-up. Reoperation was performed in one-fourth of these patients but was not effective, whether performed within 9 months (hazard ratio, 0.86; p = 0.256) or after 9 months (hazard ratio, 0.98; p = 0.860) of initial surgery, whereas second-line chemotherapy with procarbazine, lomustine, and vincristine (PCV) or with temozolomide improved survival (hazard ratio, 0.77; p = 0.008). Surgery followed by radiotherapy and chemotherapy should be considered in all patients with glioblastoma, and these treatments should not be withheld because of increasing age alone. The benefit of second surgery at recurrence is uncertain, and new trials are needed to assess its effectiveness. Chemotherapy with PCV or temozolomide seems to be a reasonable option at tumor recurrence.

Prognostic factors for survival in 676 consecutive patients with newly diagnosed primary glioblastoma

Reliable data on large cohorts of patients with glioblastoma are needed because such studies differ importantly from trials that have a strong bias toward the recruitment of younger patients with a higher performance status. We analyzed the outcome of 676 patients with histologically confirmed newly diagnosed glioblastoma who were treated consecutively at a single institution over a 7-year period (1997-2003) with follow-up to April 30, 2006. Survival probabilities were 57% at 1 year, 16% at 2 years, and 7% at 3 years. Progression-free survival was 15% at 1 year. Prolongation of survival was significantly associated with surgery in patients with a good performance status, whatever the patient's age, with an adjusted hazard ratio of 0.55 (p < 0.001) or a 45% relative decrease in the risk of death. Radiotherapy and chemotherapy improved survival, with adjusted hazard ratios of 0.61 (p = 0.001) and 0.89 (p = 0.04), respectively, regardless of age, performance status, or residual tumor volume. Recurrence occurred in 99% of patients throughout the follow-up. Reoperation was performed in one-fourth of these patients but was not effective, whether performed within 9 months (hazard ratio, 0.86; p = 0.256) or after 9 months (hazard ratio, 0.98; p = 0.860) of initial surgery, whereas second-line chemotherapy with procarbazine, lomustine, and vincristine (PCV) or with temozolomide improved survival (hazard ratio, 0.77; p = 0.008). Surgery followed by radiotherapy and chemotherapy should be considered in all patients with glioblastoma, and these treatments should not be withheld because of increasing age alone. The benefit of second surgery at recurrence is uncertain, and new trials are needed to assess its effectiveness. Chemotherapy with PCV or temozolomide seems to be a reasonable option at tumor recurrence.

Improvement of functional outcome after radical surgery in glioblastoma patients: the efficacy of a navigation-guided fence-post procedure and neurophysiological monitoring

This retrospective study investigated the functional outcomes of patient with glioblastoma receiving radical surgery before and after the adoption of the navigation-guided fence-post (NGFP) procedure and neurophysiological monitoring. We investigated 42 glioblastoma patients receiving radical surgery in our institute between 1980 and 2005. Of the 42 patients, 18 patients from 1980 to 1996 (1st term) underwent radical surgery without navigation system guidance, NGFP, or neurophysiological monitoring; 11 patients from 1997 to 2002 (2nd term) underwent surgery with simple navigation system guidance but without NGFP procedure or neurophysiological monitoring, and 13 patients from 2003 to 2005 (3rd term) underwent surgery with the NGFP procedure and neurophysiological monitoring as appropriate. There were no significance differences between any of the three term groups in age, gender, preoperative KPS score, or 'surgical staging for glioma' according to the difficulty of surgery. The rates of 95% or greater volume reduction in each term were 38.9%, 54.5% and 76.9%. The rates of morbidity were 38.9%, 18.1% and 0%. The change in KPS scores (delta KPS) before and after the perioperative period in each term were -16.1 +/- 6.6 SEM, -9.0 +/- 5.8 SEM and +8.5 +/- 3.7 SEM, respectively. The delta KPS in the 3rd term was significantly better than those of 1st and 2nd terms (P < 0.01, Kruskal-Wallis rank test). The rate of patients who were discharged to home and who resumed daily useful life without assistance was 38.9%, 63.6% and 84.6% in each term, respectively. The mean survival times in each term were 9.9, 14.0 and 16.8 months. The introduction of the NGFP procedure and neurophysiological monitoring in glioblastoma radical surgery improved the functional outcome of patients.