Radiotherapy plus concomitant and adjuvant temozolomide for glioblastoma

An era of rapid advancement: diagnosis and treatment of metastatic brain cancer

The past decade has been marked by significant improvements in the survival of patients with metastatic brain tumors, but the management of this disease presents a continuing challenge because of the varied nature of brain metastases and the limited survival time. Brain metastases are becoming more prevalent because of improvements in the treatment of extracranial lesions; this paradox brought together a seven-member multidisciplinary panel to discuss some of the most promising developments in imaging, surgical, and therapeutic techniques for metastatic brain tumors, and to address the perplexing challenges that remain. Their analyses are captured in this supplement, which begins here with an overview of metastatic brain cancer.

Cerebral radiation necrosis: incidence, outcomes, and risk factors with emphasis on radiation parameters and chemotherapy

PURPOSE

To investigate radiation necrosis in patients treated for glioma in terms of incidence, outcomes, predictive and prognostic factors.

METHODS AND MATERIALS

Records were reviewed for 426 patients followed up until death or for at least 3 years. Logistic regression analysis was performed to identify predictive and prognostic factors. Multivariate survival analysis was conducted using Cox proportional hazards regression. Separate analyses were performed for the subset of 352 patients who received a biologically effective dose (BED) > or =85.5 Gy2 (> or =45 Gy/25 fractions) who were at highest risk for radionecrosis.

RESULTS

Twenty-one patients developed radionecrosis (4.9%). Actuarial incidence plateaued at 13.3% after 3 years. In the high-risk subset, radiation parameters confirmed as risk factors included total dose (p < 0.001), BED (p < 0.005), neuret (p < 0.001), fraction size (p = 0.028), and the product of total dose and fraction size (p = 0.001). No patient receiving a BED <96 Gy2 developed radionecrosis. Subsequent chemotherapy significantly increased the risk of cerebral necrosis (p = 0.001) even when adjusted for BED (odds ratio [OR], 5.8; 95% confidence interval [CI], 1.6-20.3) or length of follow-up (OR, 5.4; 95% CI, 1.5-19.3). Concurrent use of valproate appeared to delay the onset of necrosis (p = 0.013). The development of radionecrosis did not affect survival (p = 0.09).

CONCLUSIONS

Cerebral necrosis is unlikely at doses below 50 Gy in 25 fractions. The risk increases significantly with increasing radiation dose, fraction size, and the subsequent administration of chemotherapy.

An update on oligodendroglial neoplasms

PURPOSE OF REVIEW

The most widely accepted brain tumor classification system remains morphology-based but the increasing knowledge of the molecular pathogenesis of oligodendroglial tumors has spurred translational research yielding new diagnostic and therapeutic paradigms. These data have accumulated rapidly and, in combination with exciting new insights in the cellular origin of these tumors, necessitate a review.

RECENT FINDINGS

'Cancer stem cells' have been identified in gliomas. Further study of these cells will not only provide information on the cellular origin and pathogenesis of these tumors but may also give rise to new treatments that target a cell pool not amenable to current therapeutic strategies. Molecular tumor characteristics have been correlated with imaging findings, treatment response and prognosis. This has enabled neuro-oncologists to take a risk-stratified approach to patients with oligodendrogliomas that optimizes treatment efficacy and minimizes toxicity. Furthermore, more accurate epidemiological data have become available from population-based studies.

SUMMARY

In spite of remarkable progress over the last 15 years, these tumors remain incurable. The search for a cure has to go on, while currently available multidisciplinary treatments are refined.

Prise en charge des gliomes malins découverts au cours d’une grossesse

INTRODUCTION

Glioma is seldom diagnosed during pregnancy. In this situation management presents difficult problems for both neuro-oncologists and obstetricians. We report four cases and discuss the management of this unusual situation.

CASE REPORT

The first patient was admitted to hospital at 29 weeks' gestation because of a generalized seizure and a right hemiparesis. MRI showed a left fronto-insular lesion. A stereotactic biopsy was obtained and revealed an anaplastic oligodendroglioma. With corticosteroids the patient remained stable until cesarean delivery at 36 weeks. In post-partum additional treatment with chemotherapy was started. The second patient was hospitalized at 26 weeks' gestation because of cranial hypertension, right hemiparesis and aphasia. MRI showed an important left fronto-parietal lesion. Partial resection was performed at 28 weeks. Histology revealed a glioblastoma multiforme. With corticosteroids the patient remained stable until cesarean delivery at 33 weeks. In post-partum additional treatment with radiotherapy and chemotherapy was started. The third patient was admitted to the hospital at 12 weeks' gestation because of cranial hypertension. MRI showed a left frontal lesion. A subtotal resection was done at 13 weeks. Histology revealed a glioblastoma multiforme. Two weeks after surgery the patient's neurological condition worsened and in agreement with the patient a therapeutic abortion was decided. Afterwards additional treatment with radiotherapy and chemotherapy was started. The last patient received combined treatment with radiotherapy and chemotherapy for local recurrence of a mesencephalic high-grade glioma. A posteriori it was discovered that the patient was at 4 months' gestation during this treatment. Cesarean delivery was done at 36 weeks. The child was normal at birth and is still in good health 5 years later.

CONCLUSION

The management of gliomas diagnosed during pregnancy should not be different from the standard management of gliomas in young non-pregnant adults. Pregnant women because of their young age can have a long survival. Their pregnancy should not prevent them from receiving the best treatment for their glioma. Treatment will depend upon clinico-radiological presentation, histology, gestational age and the patient's desires. Generally speaking, surgical resection of high-grade gliomas should not be delayed during pregnancy. Progress in anesthesia and neurosurgery have greatly reduced the risks for the foetus. After delivery, if the delay between surgery and delivery is too long it is possible to begin cerebral radiotherapy during pregnancy. After the first trimester of gestation this treatment can be given without any important risks for the child.

A Lactosylated Steroid Contributes in Vivo Therapeutic Benefits in Experimental Models of Mouse Lymphoma and Human Glioblastoma

Various mono- and disaccharides were grafted onto a steroid backbone. Whereas in vitro these glycosylated steroids had no cytotoxic effects on six different human cancer cell lines, several of the glycosylated steroids under study did significantly modify the levels of in vitro migration of the human U373 glioblastoma, the A549 non-small-cell-lung cancer (NSCLC), and the PC-3 prostate cancer cells, with more pronounced effects in the case of a monosubstituted beta-L-fucopyranosyl-steroid (19), a monosubstituted beta-D-isomaltosyl-steroid (22), and a monosubstituted beta-D-lactosyl-steroid (24). These three compounds significantly increased the survival of conventional mice grafted subcutaneously with the P388 lymphoma, a lymphoma that metastasizes toward the liver. In vivo, the monosubstituted beta-D-lactosyl-steroid (24) also increased the antitumor effectiveness of cisplatin, a cytotoxic pro-apoptotic drug, in the case of the P388 lymphoma model. This compound also increased the survival of immunodeficient mice into whose brains human U373 glioblastoma cells had been orthotopically grafted.

Clinical investigation survival prediction in high-grade gliomas by MRI perfusion before and during early stage of RT

PURPOSE

To determine whether cerebral blood volume (CBV) and cerebral blood flow can predict the response of high-grade gliomas to radiotherapy (RT) by taking into account spatial heterogeneity and temporal changes in perfusion.

METHODS AND MATERIALS

Twenty-three patients with high-grade gliomas underwent conformal RT, with magnetic resonance imaging perfusion before and at Weeks 1-2 and 3-4 during RT. Tumor perfusion was classified as high, medium, or low. The prognostic values of pre-RT perfusion and the changes during RT for early prediction of tumor response to RT were evaluated.

RESULTS

The fractional high-CBV tumor volume before RT and the fluid-attenuated inversion recovery imaging tumor volume were identified as predictors for survival (p = 0.01). Changes in tumor CBV during the early treatment course also predicted for survival. Better survival was predicted by a decrease in the fractional low-CBV tumor volume at Week 1 of RT vs. before RT, a decrease in the fractional high-CBV tumor volume at Week 3 vs. Week 1 of RT, and a smaller pre-RT fluid-attenuated inversion recovery imaging tumor volume (p = 0.01).

CONCLUSION

Early temporal changes during RT in heterogeneous regions of high and low perfusion in gliomas might predict for different physiologic responses to RT. This might also open the opportunity to identify tumor subvolumes that are radioresistant and might benefit from intensified RT.

Perfusion and diffusion MRI of glioblastoma progression in a four-year prospective temozolomide clinical trial

PURPOSE

This study was performed to determine the impact of perfusion and diffusion magnetic resonance imaging (MRI) sequences on patients during treatment of newly diagnosed glioblastoma. Special emphasis has been given to these imaging technologies as tools to potentially anticipate disease progression, as progression-free survival is frequently used as a surrogate endpoint.

METHODS AND MATERIALS

Forty-one patients from a phase II temolozomide clinical trial were included. During follow-up, images were integrated 21 to 28 days after radiochemotherapy and every 2 months thereafter. Assessment of scans included measurement of size of lesion on T1 contrast-enhanced, T2, diffusion, and perfusion images, as well as mass effect. Classical criteria on tumor size variation and clinical parameters were used to set disease progression date.

RESULTS

A total of 311 MRI examinations were reviewed. At disease progression (32 patients), a multivariate Cox regression determined 2 significant survival parameters: T1 largest diameter (p < 0.02) and T2 size variation (p < 0.05), whereas perfusion and diffusion were not significant.

CONCLUSION

Perfusion and diffusion techniques cannot be used to anticipate tumor progression. Decision making at disease progression is critical, and classical T1 and T2 imaging remain the gold standard. Specifically, a T1 contrast enhancement over 3 cm in largest diameter together with an increased T2 hypersignal is a marker of inferior prognosis.

Phase II trial of temozolomide in children with recurrent high-grade glioma

PURPOSE

The objective of the study was to evaluate the efficacy and toxicity of Temozolomide (TMZ) administered for 5 consecutive days in three daily dosing in children with recurrent or refractory high-grade glioma.

PATIENTS AND METHODS

Twenty-four patients with a median age of 10.5 years were enrolled onto this open-label, multicenter, phase II study. The patients were previously treated with surgical resection (17 of 24), radiotherapy (19 of 24) and chemotherapy (18 of 24). Therapy was administered orally three times a day for 5 consecutive days at the dose of 200 mg/m(2)/dx5 for chemotherapy naive patients. In patients heavily pretreated with chemotherapy the starting dose was of 150 mg/m(2)/dx5.

RESULTS

A total of 95 cycles were administered. The median progression free-survival (PFS) was 3 months for the entire group while disease stabilization was obtained in 7 patients (29.1%), all with supratentorial tumors. No CR or PR was observed. TMZ treatment showed a limited toxicity. Thrombocytopenia was the most common hematological adverse effect. Our data suggest a marginal activity of TMZ in children with recurrent high-grade glioma.

Recent developments in the use of chemotherapy in brain tumours

Several recent studies have further clarified the role of chemotherapy in newly diagnosed anaplastic glioma. For newly diagnosed glioblastoma, combined daily radiotherapy with daily temozolomide followed by six cycles of adjuvant temozolomide improves overall survival. This benefit is especially observed in patients with a methylated promotor of the MGMT gene which encodes an alkyltransferase; this observation however, needs confirmation. Although oligodendroglial tumours are sensitive to chemotherapy, classical adjuvant nitrosourea-based chemotherapy does not improve overall survival in newly diagnosed anaplastic oligodendroglioma, even in the subset of 1p/19q loss tumours. It may increase progression-free survival however, and further studies must show if combined modality treatment with daily chemotherapy during radiotherapy increases survival. Trials exploring the role of chemotherapy in low-grade glioma are ongoing. No standard chemotherapy is currently available for highly anaplastic glioma failing first-line temozolomide-based therapy.

Patients with high-grade gliomas harboring deletions of chromosomes 9p and 10q benefit from temozolomide treatment

Surgical cure of glioblastomas is virtually impossible and their clinical course is mainly determined by the biologic behavior of the tumor cells and their response to radiation and chemotherapy. We investigated whether response to temozolomide (TMZ) chemotherapy differs in subsets of malignant glioblastomas defined by genetic lesions. Eighty patients with newly diagnosed glioblastoma were analyzed with comparative genomic hybridization and loss of heterozygosity. All patients underwent radical resection. Fifty patients received TMZ after radiotherapy (TMZ group) and 30 patients received radiotherapy alone (RT group). The most common aberrations detected were gains of parts of chromosome 7 and losses of 10q, 9p, or 13q. The spectrum of genetic aberrations did not differ between the TMZ and RT groups. Patients treated with TMZ showed significantly better survival than patients treated with radiotherapy alone (19.5 vs 9.3 months). Genomic deletions on chromosomes 9 and 10 are typical for glioblastoma and associated with poor prognosis. However, patients with these aberrations benefited significantly from TMZ in univariate analysis. In multivariate analysis, this effect was pronounced for 9p deletion and for elderly patients with 10q deletions, respectively. This study demonstrates that molecular genetic and cytogenetic analyses potentially predict responses to chemotherapy in patients with newly diagnosed glioblastomas.

Epidermal growth factor receptor inhibition for the treatment of glioblastoma multiforme and other malignant brain tumours

Gliomas are the most common primary central nervous system tumours and about 55% are glioblastoma multiforme (GBM). Between 40% and 50% of GBM have dysregulated epidermal growth factor receptor (HER1/EGFR), and almost half of these co-express the mutant receptor subtype EGFRvIII, which may contribute to the aggressive and refractory course of GBM. Limited therapeutic options exist for GBM, and recurrence is common. Standard therapy is surgical resection, where possible, and radiotherapy. Adjuvant chemotherapy provides a modest survival benefit. New therapies are essential, and HER1/EGFR-targeted agents may provide a viable strategy. The HER1/EGFR tyrosine kinase inhibitors erlotinib and gefitinib are in advanced clinical development for glioma, and a number of trials are in progress, or have recently been completed. Preliminary results with gefitinib show no objective responses, but do provide evidence of disease control. In contrast, preliminary data with erlotinib appear more encouraging. Erlotinib inhibits wild-type HER1/EGFR and EGFRvIII, which may underlie its promising clinical activity. Other HER1/EGFR-targeted agents are also being investigated for glioma, including monoclonal antibodies, radio-immuno conjugates, ligand-toxin conjugates, antisense oligonucleotides and ribozymes. Further studies will define their clinical potential and hopefully provide new, effective treatments for GBM and other malignant brain tumours.

Immunotherapy for human glioma: innovative approaches and recent results

The outcome for malignant glioma patients remains dismal despite treatment with surgical resection, radiation and chemotherapy. The goal of immunotherapy is to eradicate or suppress the residual infiltrative component of these tumors. Although there is clinical evidence for cell-mediated antiglioma activity, there are special considerations that need to be accounted for in the design of immunotherapeutics for CNS tumors, such as possible differences in antigen-presenting cells, trafficking of effector T-cells and immunosuppression. Previously characterized immunosuppression in glioma patients has included low peripheral blood lymphocyte counts, reduced delayed type hypersensitivity reactions to recall antigens, impaired mitogen-induced blastogenic responses by peripheral blood mononuclear cells, increased CD8+ suppressor T-cells, decreased CD4+ T-cell activity in vitro, diminished immunoglobulin synthesis by B-cells and impaired transmembrane signaling through the T-cell receptor/CD3 complex. Recent impairments that are being identified include anergy, failure of costimulation, lack of sufficient numbers of functional effector T-cells and the presence of T-suppressor cells within the tumor microenvironment. It is proposed that these inherent problems will need to be overcome in order for immunotherapies to realize their potential. Paradoxically, the efficacy of recent clinical immunotherapies for glioma patients appears equivalent to that seen in other cancer immunotherapeutic approaches. This review will provide an overview of the juxtaposition of the immune system and CNS, and will discuss the most recent and ongoing immunotherapeutic clinical trials that are demonstrating promising results.

Phase II study of temozolomide and thalidomide in patients with metastatic neuroendocrine tumors

PURPOSE

Standard, intravenous chemotherapy regimens for neuroendocrine tumors have been associated with limited response rates and significant toxicity. We evaluated the efficacy of an oral regimen of temozolomide and thalidomide in patients with metastatic carcinoid, pheochromocytoma, or pancreatic neuroendocrine tumors.

PATIENTS AND METHODS

Twenty-nine patients were treated with a combination of temozolomide, administered at a dose of 150 mg/m2 for 7 days, every other week, and thalidomide at doses of 50 to 400 mg daily. Patients were followed for evidence of toxicity, biochemical response, radiologic response, and survival.

RESULTS

Treatment with temozolomide and thalidomide was associated with an objective biochemical (chromogranin A) response rate of 40%, and a radiologic response rate of 25% (45% among pancreatic endocrine tumors, 33% among pheochromocytomas, and 7% among carcinoid tumors). The median duration of response was 13.5 months, 1-year survival was 79%, and 2-year survival was 61%. The median administered dose of temozolomide was 150 mg/m(2), and the median administered dose of thalidomide was 100 mg daily. Grade 3-4 toxicities were uncommon, with the exception of grade 3-4 lymphopenia, which developed in 69% of the patient population. Opportunistic infections occurred in three patients (10%) during the time of lymphopenia, and included single cases of Pneumocystis carinii pneumonia, disseminated varicella zoster virus, and herpes simplex virus.

CONCLUSION

Orally administered temozolomide and thalidomide seems to be an active regimen for the treatment of neuroendocrine tumors. In this 29-patient study, this regimen appeared more active in pancreatic endocrine tumors than in carcinoid tumors.

Salvage radioimmunotherapy with murine iodine-131-labeled antitenascin monoclonal antibody 81C6 for patients with recurrent primary and metastatic malignant brain tumors: phase II study results

PURPOSE

To assess the efficacy and toxicity of intraresection cavity iodine-131-labeled murine antitenascin monoclonal antibody 81C6 (131I-m81C6) among recurrent malignant brain tumor patients.

PATIENTS AND METHODS

In this phase II trial, 100 mCi of 131I-m81C6 was injected directly into the surgically created resection cavity (SCRC) of 43 patients with recurrent malignant glioma (glioblastoma multiforme [GBM], n = 33; anaplastic astrocytoma [AA], n = 6; anaplastic oligodendroglioma [AO], n = 2; gliosarcoma [GS], n = 1; and metastatic adenocarcinoma, n = 1) followed by chemotherapy.

RESULTS

With a median follow-up of 172 weeks, 63% and 59% of patients with GBM/GS and AA/AO tumors were alive at 1 year. Median overall survival for patients with GBM/GS and AA/AO tumors was 64 and 99 weeks, respectively. Ten patients (23%) developed acute hematologic toxicity. Five patients (12%) developed acute reversible neurotoxicity. One patient (2%) developed irreversible neurotoxicity. No patients required reoperation for radionecrosis.

CONCLUSION

In this single-institution phase II study, administration of 100 mCi of 131I-m81C6 to recurrent malignant glioma patients followed by chemotherapy is associated with a median survival that is greater than that of historical controls treated with surgery plus iodine-125 brachytherapy. Furthermore, toxicity was acceptable. Administration of a fixed millicurie dose resulted in a wide range of absorbed radiation doses to the SCRC. We are now conducting a phase II trial, approved by the US Food and Drug Administration, using patient-specific 131I-m81C6 dosing, to deliver 44 Gy to the SCRC followed by standardized chemotherapy. A phase III multicenter trial with patient-specific dosing is planned.

Food and Drug Administration Drug approval summary: temozolomide plus radiation therapy for the treatment of newly diagnosed glioblastoma multiforme

On March 15, 2005, the U.S. Food and Drug Administration approved temozolomide (Temodar capsules, Schering-Plough Research Institute) for the treatment of adult patients with newly diagnosed glioblastoma multiforme concomitantly with radiotherapy and then as maintenance treatment. Five hundred seventy-three glioblastoma multiforme patients were randomized to receive either temozolomide + radiotherapy (n = 287) or radiotherapy alone (n = 286). Patients in the temozolomide + radiotherapy arm received concomitant temozolomide (75 mg/m2) once daily for the duration of radiation therapy (42-49 days). This was followed, 4 weeks later, by six cycles of temozolomide, 150 or 200 mg/m2 daily for 5 days, every 4 weeks. Patients in the control arm received radiotherapy only. In both arms, radiotherapy was delivered as 60 Gy/30 fractions to the tumor site with a 2 to 3 cm margin. Pneumocystis carinii pneumonia prophylaxis was required during temozolomide + radiotherapy treatment and was continued until recovery of lymphocytopenia (Common Toxicity Criteria grade <1). At disease progression, temozolomide salvage treatment was given to 161 of 282 patients (57%) in the radiotherapy alone arm, and to 62 of 277 patients (22%) in the temozolomide + radiotherapy arm. Patients receiving concomitant and maintenance temozolomide + radiotherapy had significantly improved overall survival. The hazard ratio was 0.63 (95% confidence interval, 0.52-0.75; log-rank, P < 0.0001). Median survival was 14.6 months (temozolomide + radiotherapy) versus 12.1 months (radiotherapy alone). Adverse events during temozolomide treatment included thrombocytopenia, nausea, vomiting, anorexia, constipation, alopecia, headache, fatigue, and convulsions.

Phase 1 Trial of Gefitinib Plus Sirolimus in Adults with Recurrent Malignant Glioma

PURPOSE

To determine the maximum tolerated dose (MTD) and dose-limiting toxicity (DLT) of gefitinib, a receptor tyrosine kinase inhibitor of the epidermal growth factor receptor, plus sirolimus, an inhibitor of the mammalian target of rapamycin, among patients with recurrent malignant glioma.

PATIENTS AND METHODS

Gefitinib and sirolimus were administered on a continuous daily dosing schedule at dose levels that were escalated in successive cohorts of malignant glioma patients at any recurrence who were stratified based on concurrent use of CYP3A-inducing anticonvulsants [enzyme-inducing antiepileptic drugs, (EIAED)]. Pharmacokinetic and archival tumor biomarker data were also assessed.

RESULTS

Thirty-four patients with progressive disease after prior radiation therapy and chemotherapy were enrolled, including 29 (85%) with glioblastoma multiforme and 5 (15%) with anaplastic glioma. The MTD was 500 mg of gefitinib plus 5 mg of sirolimus for patients not on EIAEDs and 1,000 mg of gefitinib plus 10 mg of sirolimus for patients on EIAEDs. DLTs included mucositis, diarrhea, rash, thrombocytopenia, and hypertriglyceridemia. Gefitinib exposure was not affected by sirolimus administration but was significantly lowered by concurrent EIAED use. Two patients (6%) achieved a partial radiographic response, and 13 patients (38%) achieved stable disease.

CONCLUSION

We show that gefitinib plus sirolimus can be safely coadministered on a continuous, daily dosing schedule, and established the recommended dose level of these agents in combination for future phase 2 clinical trials.

Phase II study of imatinib mesylate plus hydroxyurea in adults with recurrent glioblastoma multiforme

PURPOSE

We performed a phase II study to evaluate the combination of imatinib mesylate, an adenosine triphosphate mimetic, tyrosine kinase inhibitor, plus hydroxyurea, a ribonucleotide reductase inhibitor, in patients with recurrent glioblastoma multiforme (GBM).

PATIENTS AND METHODS

Patients with GBM at any recurrence received imatinib mesylate plus hydroxyurea (500 mg twice a day) orally on a continuous, daily schedule. The imatinib mesylate dose was 500 mg twice a day for patients on enzyme-inducing antiepileptic drugs (EIAEDs) and 400 mg once a day for those not on EIAEDs. Assessments were performed every 28 days. The primary end point was 6-month progression-free survival (PFS).

RESULTS

Thirty-three patients enrolled with progressive disease after prior radiotherapy and at least temozolomide-based chemotherapy. With a median follow-up of 58 weeks, 27% of patients were progression-free at 6 months, and the median PFS was 14.4 weeks. Three patients (9%) achieved radiographic response, and 14 (42%) achieved stable disease. Cox regression analysis identified concurrent EIAED use and no more than one prior progression as independent positive prognostic factors of PFS. The most common toxicities included grade 3 neutropenia (16%), thrombocytopenia (6%), and edema (6%). There were no grade 4 or 5 events. Concurrent EIAED use lowered imatinib mesylate exposure. Imatinib mesylate clearance was decreased at day 28 compared with day 1 in all patients, suggesting an effect of hydroxyurea.

CONCLUSION

Imatinib mesylate plus hydroxyurea is well tolerated and associated with durable antitumor activity in some patients with recurrent GBM.

Changing Paradigms—An Update on the Multidisciplinary Management of Malignant Glioma

Treatment of malignant glioma requires a multidisciplinary team. Treatment includes surgery, radiotherapy, and chemotherapy. Recently developed agents have demonstrated activity against recurrent malignant glioma and efficacy if given concurrently with radiotherapy in the upfront setting. Oligodendroglioma with 1p/19q deletions has been recognized as a distinct pathologic entity with particular sensitivity to radiotherapy and chemotherapy. Randomized trials have shown that early neoadjuvant or adjuvant administration of procarbazine, lomustine, and vincristine chemotherapy prolongs disease-free survival; however, it has no impact on overall survival. Temozolomide, a novel alkylating agent, has shown modest activity against recurrent glioma. In combination with radiotherapy in newly diagnosed patients with glioblastoma, temozolomide significantly prolongs survival. Molecular studies have demonstrated that the benefit is mainly observed in patients whose tumors have a methylated methylguanine methyltransferase gene promoter and are thus unable to repair some of the chemotherapy-induced DNA damage. For lower-grade glioma, the use of chemotherapy remains limited to recurrent disease, and first-line administration is the subject of ongoing clinical trials. Irinotecan and agents like gefitinib, erlotinib, and imatinib targeting the epidermal growth factor receptor and platelet-derived growth factor receptor have shown some promise in recurrent malignant glioma. This review summarizes recent developments, focusing on the clinical management of patients in daily neuro-oncology practice.

A phase 1-2, prospective, double blind, randomized study of the safety and efficacy of Sulfasalazine for the treatment of progressing malignant gliomas: study protocol of [ISRCTN45828668]

Background

The prognosis of patients suffering from WHO grade 3 and 4 astrocytic glioma remains poor despite surgery, radiation therapy and the use of current chemotherapy regimen. Indeed, the median survival of glioblastoma multiforme (WHO grade 4) patients is at best 14.6 month with only 26.5 percents of the patients still alive after 2 years and the median survival of anaplastic astrocytomas (WHO grade 3) is 19.2 month. Recent evidence suggests that the transcription factor NF-kappaB is constitutively expressed in malignant gliomas and that its inhibition by drugs like Sulfasalazine may block the growth of astrocytic tumors in vitro and in experimental models of malignant gliomas.

Design

ULg_GBM_04/1 is a prospective, randomized, double blind single-center phase 1–2 study. A total of twenty patients with progressive malignant glioma despite surgery, radiation therapy and a first line of chemotherapy will be recruited and assigned to four dosage regimen of Sulfasalazine. This medication will be taken orally t.i.d. at a daily dose of 1.5–3–4 or 6 g, continuously until complete remission, evidence of progression or drug intolerance. Primary endpoints are drug safety in the setting of malignant gliomas and tumor response as measured according to MacDonald's criteria. An interim analysis of drug safety will be conducted after the inclusion of ten patients. The complete evaluation of primary endpoints will be conducted two years after the enrolment of the last patient or after the death of the last patient should this occur prematurely.

Discussion

The aim of this study is to evaluate the safety and efficacy of Sulfasalazine as a treatment for recurring malignant gliomas. The safety and efficacy of this drug are analyzed as primary endpoints. Overall survival and progression-free survival are secondary endpoint.

Targeted Modulation of MGMT: Clinical Implications: Fig. 1

O(6)-Methylguanine DNA methyltransferase (MGMT) has been studied for >20 years as a gene that is associated with the mutagenicity and cytotoxicity induced by either methylating carcinogens or alkylating (methylating and chloroethylating) therapeutic agents. Pioneering studies of alkylating agents identified alkylated guanine at the O(6) position, the substrate of MGMT, as a potentially promutagenic and lethal toxic DNA lesion. MGMT plays a prominent role in DNA adduct repair that limits the mutagenic and cytotoxic effect of alkylating agents. Because of its role in cancer etiology and chemotherapy resistance, MGMT is of particular interest. In this article, the clinical effect of MGMT expression and targeted modulation of MGMT will be summarized.

Effect of chemotherapy-induced DNA repair on oncolytic herpes simplex viral replication

BACKGROUND

Gliomas treated with the alkylating agent temozolomide have incomplete responses in part because of tumoral repair of chemotherapy-induced DNA damage. Data from phase I trials suggest that G207, an oncolytic herpes simplex virus (HSV) with mutated ribonucleotide reductase (RR) and gamma34.5 genes, is safe but needs greater viral oncolysis to be effective. We hypothesized that temozolomide and G207 treatment limitations could be jointly addressed using temozolomide-induced tumor-protective DNA repair pathways to enhance viral replication.

METHODS

Human glioblastoma cells (U87, T98, and U373) and U87 cells transfected with the gene for the DNA repair enzyme O6-methylguanine DNA methyltransferase (MGMT) were treated with G207 and/or temozolomide. Drug interactions, expression of the growth arrest DNA damage 34 (GADD34) and RR transcripts before and after their knockdown with short interfering RNAs, DNA strand breaks, and apoptosis were measured using Chou-Talalay analysis, real-time reverse transcription-polymerase chain reaction, the comet assay, and flow cytometry, respectively. Survival of mice (groups of ten) with intracranial U87 xenograft tumors treated with temozolomide and/or G207 was analyzed using Kaplan-Meier analysis.

RESULTS

Temozolomide exhibited strong synergy with G207 in both MGMT-negative and the MGMT inhibitor O6-benzylguanine-treated MGMT-expressing gliomas (Chou-Talalay combination indices = 0.005 to 0.39) and induced GADD34 expression primarily in nonapoptotic MGMT-negative U87 glioma cells (fold difference = 16, 95% confidence interval [CI] = 12.6 to 20.4, compared with untreated cells). MGMT-expressing T98 and U87/MGMT cells treated with temozolomide plus O6-benzylguanine had higher RR expression than untreated cells (fold difference =14.9, 95% CI = 10.1 to 22.0 [T98]; 9.9, 95% CI = 7.0 to 13.8 [U87/MGMT]). GADD34 and RR knockdown increased temozolomide-induced DNA damage and inhibited the synergy of G207 and temozolomide in U87 and O6-benzylguanine-treated U87/MGMT cells. Mice bearing intracranial U87 tumors survived longer after combination therapy (100% survival at 90 days) than after single-agent therapy (median survival = 46 and 48 days with G207 and temozolomide treatment, respectively).

CONCLUSIONS

Temozolomide-induced DNA repair pathways vary with MGMT expression and enhance HSV-mediated oncolysis in glioma cells. These findings unveil the potential of HSV to target cells surviving temozolomide treatment.

Tumor Necrosis Factor-α–Induced Protein 3 As a Putative Regulator of Nuclear Factor-κB–Mediated Resistance to O6-Alkylating Agents in Human Glioblastomas

Purpose

Pre-existing and acquired drug resistance are major obstacles to the successful treatment of glioblastomas.

Methods

We used an integrated resistance model and genomics tools to globally explore molecular factors and cellular pathways mediating resistance to O6-alkylating agents in glioblastoma cells.

Results

We identified a transcriptomic signature that predicts a common in vitro and in vivo resistance phenotype to these agents, a proportion of which is imprinted recurrently by gene dosage changes in the resistant glioblastoma genome. This signature was highly enriched for genes with functions in cell death, compromise, and survival. Modularity was a predominant organizational principle of the signature, with functions being carried out by groups of interacting molecules in overlapping networks. A highly significant network was built around nuclear factor-κB (NF-κB), which included the persistent alterations of various NF-κB pathway elements. Tumor necrosis factor-α–induced protein 3 (TNFAIP3) was identified as a new regulatory component of a putative cytoplasmic signaling cascade that mediates NF-κB activation in response to DNA damage caused by O6-alkylating agents. Expression of the corresponding zinc finger protein A20 closely mirrored the expression of the TNFAIP3 transcript, and was inversely related to NF-κB activation status in the resistant cells. A prediction model based on the resistance signature enabled the subclassification of an independent, validation cohort of 31 glioblastomas into two outcome groups (P = .037) and revealed TNFAIP3 as part of an optimized four-gene predictor associated significantly with patient survival (P = .022).

Conclusion

Our results offer strong evidence for TNFAIP3 as a key regulator of the cytoplasmic signaling to activate NF-κB en route to O6-alkylating agent resistance in glioblastoma cells. This pathway may be an attractive target for therapeutic modulation of glioblastomas.

O6-methylguanine DNA methyltransferase and p53 status predict temozolomide sensitivity in human malignant glioma cells

Temozolomide (TMZ) is a methylating agent which prolongs survival when administered during and after radiotherapy in the first-line treatment of glioblastoma and which also has significant activity in recurrent disease. O6-methylguanine DNA methyltransferase (MGMT) is a DNA repair enzyme attributed a role in cancer cell resistance to O6-alkylating agent-based chemotherapy. Using a panel of 12 human glioma cell lines, we here defined the sensitivity to TMZ in acute cytotoxicity and clonogenic survival assays in relation to MGMT, mismatch repair and p53 status and its modulation by dexamethasone, irradiation and BCL-X(L). We found that the levels of MGMT expression were a major predictor of TMZ sensitivity in human glioma cells. MGMT activity and clonogenic survival after TMZ exposure are highly correlated (p < 0.0001, r2 = 0.92). In contrast, clonogenic survival after TMZ exposure does not correlate with the expression levels of the mismatch repair proteins mutS homologue 2, mutS homologue 6 or post-meiotic segregation increased 2. The MGMT inhibitor O6-benzylguanine sensitizes MGMT-positive glioma cells to TMZ whereas MGMT gene transfer into MGMT-negative cells confers protection. The antiapoptotic BCL-X(L) protein attenuates TMZ cytotoxicity in MGMT-negative LNT-229 but not in MGMT-positive LN-18 cells. Neither ionizing radiation (4 Gy) nor clinically relevant concentrations of dexamethasone modulate MGMT activity or TMZ sensitivity. Abrogation of p53 wild-type function strongly attenuates TMZ cytotoxicity. Conversely, p53 mimetic agents designed to stabilize the wild-type conformation of p53 sensitize glioma cells for TMZ cytotoxicity. Collectively, these results suggest that the determination of MGMT expression and p53 status will help to identify glioma patients who will or will not respond to TMZ.

Diffusion tensor imaging: possible implications for radiotherapy treatment planning of patients with high-grade glioma

AIMS

Radiotherapy treatment planning for high-grade gliomas (HGG) is hampered by the inability to image peri-tumoural white-matter infiltration. Diffusion tensor imaging (DTI) is an imaging technique that seems to show white-matter abnormalities resulting from tumour infiltration that cannot be visualised by conventional computed tomography or magnetic resonance imaging (MRI). We propose a new term, the image-based high-risk volume (IHV) for such abnormalities, which are distinct from the gross-tumour volume (GTV). For IHV based on DTI, we use the term IHVDTI. This study assesses the value of DTI for the individualisation of radiotherapy treatment planning for patients with HGG.

METHODS

Seven patients with biopsy-proven HGG were included in a theoretical planning exercise, comparing standard planning techniques with individualised plans based on DTI. Standard plans were generated using a 2.5 cm clinical target volume (CTV) margin added to the GTV. For DTI-based plans, the CTV was generated by adding a 1 cm margin to the IHVDTI. Estimates of normal tissue complication probability (NTCP) were calculated and used to estimate the level of dose escalation that could be achieved using the DTI-based plans.

RESULTS

The use of DTI resulted in non-uniform margins being added to the GTV to encompass areas at high risk of tumour involvement, but, in six out of seven cases, the IHVDTI was encapsulated by the standard CTV margin. In all cases, DTI could be used to reduce the size of the planning-target volume (PTV) (mean 35%, range 18-46%), resulting in escalated doses (mean 67 Gy, range 64-74 Gy), with NTCP levels that matched the conventional treatment plans.

CONCLUSION

DTI can be used to individualise radiotherapy target volumes, and reduction in the CTV permits modest dose escalation without an increase in NTCP. DTI may also be helpful in stratifying patients according to the degree of white-matter infiltration.

Phase I study of capecitabine in combination with temozolomide in the treatment of patients with brain metastases from breast carcinoma

BACKGROUND

A single-institution Phase I clinical trial was conducted to determine the maximum tolerated dose (MTD) and define the safety profile of temozolomide and capecitabine when used in combination to treat brain metastases from breast cancer.

METHODS

Patients were eligible if they had bidimensionally measurable supratentorial or infratentorial brain metastasis from histologically confirmed breast carcinoma. Patients could have received up to 3 prior chemotherapy regimens. Temozolomide and capecitabine were administered concomitantly to 4 sequential cohorts at different dosing levels on Days 1-5 and Days 8-12, with cycles repeated every 21 days until disease progression.

RESULTS

Twenty-four patients with multiple brain lesions were treated, including 14 patients with newly diagnosed brain metastases and 10 patients with recurrent brain metastases. Only 1 patient was chemotherapy-naive. Fatigue and nausea were the most commonly observed toxicities observed at any dose levels. Significant antitumor activity was observed, with a total of 1 complete and 3 partial responses (18% objective response rate) in the brain. The median response duration was 8 weeks (range, 6-64 weeks) and the median time to progression in the brain was 12 weeks (range, 3-70 weeks). Neurocognitive function improved or remained stable in patients with a response or stable disease.

CONCLUSIONS

The combination of temozolomide and capecitabine is an active, well-tolerated regimen. The observed antitumor activity warrants further evaluation of this combination as an alternative to or in combination with whole-brain radiation therapy for the treatment of multiple brain metastases.

Intracranial therapy of glioblastoma with the fusion protein DTIL13 in immunodeficient mice

A fusion protein consisting of human interleukin-13 and the first 389 amino acids of diphtheria toxin was assembled in order to target human glioblastoma cell lines in a murine intracranial model. In vitro studies to determine specificity indicated that the protein called DTIL13 was highly selective for human glioblastoma. In vivo, the maximum tolerated dose of DTIL13 was 1 microg/injection given every other day and repeated for 3 days. Doses that exceeded this amount resulted in weight loss and liver damage as determined by histology and enzyme assay. Experiments in IL-4 receptor knockout mice revealed that liver toxicity was receptor-related. This same dose given to nude mice with established U373 MG brain tumors resulted in significant reductions in tumor volume and significantly prolonged survival (p<0.0001). Magnetic resonance imaging (MRI) proved to be extremely useful in (i) determining the ability of DTIL13 to reduce tumor size and (ii) for studying toxicity since diffusion-weighted and gradient echo-weighted MRI revealed that vascular leak syndrome was not a limiting toxicity at this dose. These results suggest that DTIL13 is as effective in an intracranial rodent model as it was in a flank model in previous studies and that DTIL13 might be an effective treatment for glioblastoma multiforme.

Phase 1 study of erlotinib HCl alone and combined with temozolomide in patients with stable or recurrent malignant glioma

The purpose of this study was to define the maximum tolerated dose of erlotinib and characterize its pharmaco-kinetics and safety profile, alone and with temozolomide, with and without enzyme-inducing antiepileptic drugs (EIAEDs), in patients with malignant gliomas. Patients with stable or progressive malignant primary glioma received erlotinib alone or combined with temozolomide in this dose-escalation study. In each treatment group, patients were stratified by coadministration of EIAEDs. Erlotinib was started at 100 mg orally once daily as a 28-day treatment cycle, with dose escalation by 50 mg/day up to 500 mg/day. Temozolomide was administered at 150 mg/m2 for five consecutive days every 28 days, with dose escalation up to 200 mg/m2 at the second cycle. Eightythree patients were evaluated. Rash, fatigue, and diarrhea were the most common adverse events and were generally mild to moderate. The recommended phase 2 dose of erlotinib is 200 mg/day for patients with glioblastoma multiforme who are not receiving an EIAED, 450 mg/day for those receiving temozolomide plus erlotinib with an EIAED, and at least 500 mg/day for those receiving erlotinib alone with an EIAED. Of the 57 patients evaluable for response, eight had a partial response (PR). Six of the 57 patients had a progression-free survival of longer than six months, including four patients with a PR. Coadministration of EIAEDs reduced exposure to erlotinib as compared with administration of erlotinib alone (33%-71% reduction). There was a modest pharmacokinetic interaction between erlotinib and temozolomide. The favorable tolerability profile and evidence of antitumor activity indicate that further investigation of erlotinib is warranted.

Conditionally replicative adenoviral vectors for malignant glioma

High-grade gliomas constitute an important challenge to modern medicine, and although great effort has been made to prolong patient survival, the prognosis for this disease remains poor. Due to recent discoveries in the molecular basis of gliomas, gene therapy is becoming a promising alternative. In this review, we discuss the use of conditionally replicative adenoviral vectors (CRAd) and their applications in neuro-oncology. Such vectors, when rendered conditionally replicative via transductional and transcriptional modifications, offer great promise for patients with malignant brain tumours. We review data from preclinical and clinical studies utilising such vectors and discuss the limitations and future perspectives of CRAd oncolytic therapy for malignant glioma.

Correlative studies in neuro-oncology trials: Should they influence treatment?

Recent molecular correlative studies accompanying clinical trials in glioma have provided strong evidence for prognostic markers and predictive factors for treatment response. However, to what extent can these markers influence the limited choice of therapeutic options? Do we further validate the markers in the next trials or move on, incorporate the markers for patient selection or stratification, aim at improving the modestly effective treatments by adding new drugs, and develop alternative therapy strategies for patients selected for their bad predictor?

Prognostic stratification of patients with anaplastic gliomas according to genetic profile

BACKGROUND

There is a need to improve the current, controversial, and poorly reproducible classification of anaplastic gliomas, which represent a highly heterogeneous entity in terms of survival.

METHODS

The impact of the most common genetic alterations on survival was investigated based on 156 anaplastic gliomas: Among the patients who were included, the gender ratio was 1.32, the median age was 45.5 years (range, 20-83 years), and the median Karnofsky performance status was 70 (range, 40-100). Genetic analysis included a search for loss of heterozygosity (LOH) on chromosomes 1p and 19q; amplification of chromosomes 9p and 10q and of the epidermal growth factor receptor (EGFR), cyclin-dependent kinase 4 (CDK4) and mouse double-minute (MDM2) genes; and p53 expression.

RESULTS

The median survival was 33.5 months, and the median progression-free survival was 15.8 months. In a univariate analysis, LOH on 1p and 19q was correlated with longer survival, whereas p53 expression, LOH on 9p, LOH on 10q, amplified EGFR, and deleted CDKN2A were correlated with shorter survival. LOH on 1p and 19q were associated with oligodendrogliomas, LOH on 10q was related to EGFR amplification, and LOH on 1p and 19q was mutually exclusive with EGFR amplification and LOH on 10q. In a multivariate analysis, the significant prognostic factors were age, histology, LOH on 1p and 19q, and P16/CDKN2A deletion. Recursive partitioning analysis (RPA) divided the whole group hierarchically into 3 distinct prognostic subgroups: Group A with 1p19q codeletion (median survival, 98 months), Group B with EGFR amplification (median survival, 17 months), and Group CC (median survival, 31 months), providing a basis for a genetically based prognostic subclassification for patients with Grade III gliomas.

CONCLUSIONS

The search for 1p19q codeletion and EGFR receptor amplification provides a simple, clinically relevant prognostic subclassification of grade III gliomas.

Low-grade gliomas: The debate continues

Low-grade gliomas (LGG) are a heterogeneous group of tumors that tend to occur primarily in young adults and children. They are indolent, progressive, and often undergo anaplastic transformation. The prognosis of these tumors is primarily affected by age and pathologic type. Many questions remain in the management of LGGs, including the role of surgical resection (ie, maximal tumor resection), the optimal timing of radiation (ie, postoperative vs at the time of tumor progression), and the role of chemotherapy (ie, salvage after radiotherapy, primary treatment after surgery, concurrent with radiotherapy). Further complicating treatment decisions are concerns about toxicity with any intervention because LGG patients can often lead a relatively normal existence for years with no intervention. In this article we review the pertinent LGG literature published over the past few years and its impact on the management of LGGs.

Targeted molecular therapy of malignant gliomas

Malignant gliomas are the most common form of primary brain tumors in adults. Despite advances in diagnosis and standard therapies such as surgery, radiation, and chemotherapy, the prognosis remains poor. Recent scientific advances have enhanced our understanding of the biology of gliomas and the role of tyrosine kinase receptors and signal transduction pathways in tumor initiation and maintenance, such as the epidermal growth factor receptors, platelet-derived growth factor receptors, vascular endothelial growth factor receptors, and the Ras/Raf/mitogen-activated protein (MAP)-kinase and phosphatidylinositol-3 kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) pathways. Novel targeted drugs such as small molecular inhibitors of these receptors and signaling pathways are showing some activity in initial studies. As we learn more about these drugs and how to optimize their use as single agents and in combination with radiation, chemotherapy, and other targeted molecular agents, they will likely play an increasing role in the management of this devastating disease. This review summarizes the current results with targeted molecular agents in malignant gliomas and strategies under evaluation to increase their effectiveness.

High-dose conformal radiotherapy for supratentorial malignant glioma: a historical comparison

BACKGROUND

Although radiotherapy remains the main postoperative treatment for patients with malignant glioma, modifications to regimens have not improved the poor outlook of patients with this disease. We aimed to investigate whether high-dose conformal radiotherapy improves the survival of patients with supratentorial malignant glioma compared with conventional radiotherapy.

METHODS

29 patients with anaplastic astrocytoma and 61 patients with glioblastoma who received high-dose conformal radiotherapy during 1990-2002 were compared with 34 patients with anaplastic astrocytoma and 60 patients with glioblastoma who received conventional 60 Gy radiotherapy during 1979-89. 77 of the 90 patients receiving high-dose radiotherapy were given 80 Gy; the remaining 13 patients, all with glioblastoma, received 90 Gy. Radiotherapy was planned on the basis of images taken before surgery, and doses were delivered in 2 Gy per fraction per day for 5 days a week. Hazard ratios for death were calculated with a Cox model, and were adjusted for age, Karnofsky performance scale, tumour size, and extent of resection.

FINDINGS

Patients who received high-dose radiotherapy had significantly longer overall survival compared with those who received conventional radiotherapy (adjusted hazard ratio 0.30 [95% CI 0.12-0.76], p=0.011 for anaplastic astrocytoma and 0.49 [0.28-0.87], p=0.014 for glioblastoma). Patients with anaplastic astrocytoma in the high-dose group have not yet reached median survival; median survival in the conventional radiotherapy group was 22.3 months (95% CI 20.6-24.0). 5-year survival was 51.3% (29.2-73.4) for the high-dose group and 14.7% (0.0-30.0) for the conventional group. Median survival in patients with glioblastoma was 16.2 months (12.8-19.6) for the high-dose group and 12.4 months (10.0-14.8) for the conventional group. 2-year survival was 38.4% (23.5-53.3) for the high-dose group and 11.4% (0.0-25.3) for the conventional group. Survival did not differ between those that received 80 Gy radiotherapy and those that received 90 Gy (hazard ratio 0.94 [95% CI 0.42-2.12]). The higher frequency of radiation-induced white matter abnormality in the high-dose group compared with the conventional radiotherapy group did not lead to increased disability.

INTERPRETATION

High-dose, standard-fractionated radiotherapy shows potential as the main postoperative treatment for patients with supratentorial malignant glioma.

Clinical Cancer Advances 2005: major research advances in cancer treatment, prevention, and screening--a report from the American Society of Clinical Oncology

This year, for the first time, the American Society of Clinical Oncology (ASCO) is publishing Clinical Cancer Advances 2005: Major Research Advances in Cancer Treatment, Prevention, and Screening, an annual review of the most significant clinical research presented or published over the past year across all cancer types. ASCO embarked on this project to provide the public, patients, policymakers, and physicians with an accessible summary of the year's most important research advances. While not intended to serve as a comprehensive review, this report provides a year-end snapshot of research that will have the greatest impact on patient care. As you will read, there is much good news from the front lines of cancer research. These pages report on new chemotherapy regimens that sharply reduce the risk of recurrence for very common cancers; the "coming of age" of targeted cancer therapies; promising studies of drugs to prevent cancer; and improvements in quality of life for people living with the disease, among many other advances. Survival rates for cancer are on the rise, increasing from 50% to 64% over the last 30 years. Cancer still exacts an enormous toll, however. Nearly 1.4 million Americans will be diagnosed this year, and some 570,000 will die of the disease. Clearly, more research is needed to find effective therapies for the most stubborn cancer types and stages. We need to know more about the long-term effects of newer, more targeted cancer therapies, some of which need to be taken over long periods of time. And we need to devote far greater attention to tracking and improving the care of the nearly 10 million cancer survivors in the United States today. Despite these and other challenges, the message of this report is one of hope. Through the dedicated, persistent pursuit of clinical research and participation in clinical trials by people with cancer, we steadily uncover new and better ways of treating, diagnosing, and preventing a disease that touches the lives of so many. I want to thank the Editorial Board members, the Specialty Editors, and the ASCO Cancer Communications Committee for their dedicated work to develop this report, and I hope you find it useful.

Health-related quality of life in patients with glioblastoma: a randomised controlled trial

BACKGROUND

A randomised controlled trial of radiotherapy alone versus radiotherapy with concomitant and adjuvant temozolomide for patients with glioblastoma showed that survival was higher for patients assigned combination treatment compared with those assigned standard radiotherapy alone. This paper reports the health-related quality of life (HRQOL) of the patients in this trial.

METHODS

573 patients with newly diagnosed glioblastoma were randomly allocated either radiotherapy alone or radiotherapy and temozolomide. The primary endpoint was survival, and HRQOL was a secondary endpoint. We assessed HRQOL at baseline and at every 3 months during treatment until progression using the European Organisation for Research and Treatment of Cancer (EORTC) quality of life questionnaire core-30 (QLQ-C30) and the EORTC brain cancer module (EORTC BN-20). We calculated changes from baseline score for seven predefined HRQOL measures (fatigue, overall health, social function, emotional function, future uncertainty, insomnia, and communication deficit) and differences between groups for these measures at every time point. The significance of, and proportions of patients with, improved HRQOL scores--defined as a change of 10 points or more--were recorded. This trial is registered on the US National Cancer Institute website http://www.cancer.gov/search/NewClinicalTrials, NCT00006353.

FINDINGS

Baseline questionnaires were available for 490 (86%) patients. Baseline HRQOL scores did not differ between groups. At first follow-up, groups differed only in social functioning, favouring the radiotherapy-only group (mean score 79.0 [SD 3.2] for patients assigned radiotherapy vs 67.4 [2.7] for those assigned radiotherapy and temozolomide; difference between groups 11.6 points [95% CI 3.5-19.7], p=0.0052). Over subsequent assessments, HRQOL was much the same between treatment groups.

INTERPRETATION

Addition of temozolomide during and after radiotherapy for patients with newly diagnosed glioblastoma significantly improved survival without a negative effect on HRQOL.

Treatment of astrocytomas

PURPOSE OF REVIEW

Astrocytomas are the most common primary brain tumors. We will review recent developments in the understanding of the biology of these neoplasms and recent trials demonstrating promising improvements in the survival of patients with malignant gliomas.

RECENT FINDINGS

Temozolomide along with radiation has become the standard of care for patients with newly diagnosed glioblastoma. Nonetheless, despite this advance in treatment, these tumors remain incurable. Biological markers and alternative treatment regimens will likely improve survival in patients with high-grade gliomas.

SUMMARY

A recent study demonstrating the benefit of combined temozolomide and radiation provides a platform on which to build new treatment regimens. Further developments in the understanding of the biology of these tumors will permit specific interventions in selected patients that ultimately will improve outcomes.

Efficacy of Fractionated Stereotactic Reirradiation in Recurrent Gliomas: Long-Term Results in 172 Patients Treated in a Single Institution

Purpose

To evaluate the efficacy of fractionated stereotactic radiotherapy (FSRT) performed as reirradiation in 172 patients with recurrent low- and high-grade gliomas.

Patients and Methods

Between 1990 and 2004, 172 patients with recurrent gliomas were treated with FSRT as reirradiation in a single institution. Seventy-one patients suffered from WHO grade 2 gliomas. WHO grade 3 gliomas were diagnosed in 42 patients, and 59 patients were diagnosed with glioblastoma multiforme (GBM). The median time between primary radiotherapy and reirradiation was 10 months for GBM, 32 months for WHO grade 3 tumors, and 48 months for grade 2 astrocytomas. FSRT was performed with a median dose of 36 Gy in a median fractionation of 5 × 2 Gy/wk.

Results

Median overall survival after primary diagnosis was 21 months for patients with GBM, 50 months for patients with WHO grade 3 gliomas, and 111 months for patients with WHO grade 2 gliomas. Histologic grading was the strongest predictor for overall survival, together with the extent of neurosurgical resection and age at primary diagnosis. Median survival after reirradiation was 8 months for patients with GBM, 16 months for patients with grade 3 tumors, and 22 months for patients with low-grade gliomas. Only time to progression and histology were significant in influencing survival after reirradiation. Progression-free survival after FSRT was 5 months for GBM, 8 months for WHO grade 3 tumors, and 12 months for low-grade gliomas.

Conclusion

FSRT is well tolerated and may be effective in patients with recurrent gliomas. Prospective studies are warranted for further evaluation.

Temozolomide: a milestone in the pharmacotherapy of brain tumors

Temozolomide (TMZ) is an alkylating agent earlier approved for recurrent anaplastic astrocytoma and approved for the treatment of newly diagnosed glioblastoma in the USA and Europe in 2005. TMZ shows good blood–brain barrier penetration and exhibits a favorable side effect profile. Its key mode of action appears to be methylation at N7 and O6-positions of guanine. The level of expression and activity of the DNA repair enzyme O6-methylguanine DNA methyltransferase is thought to be a major predictor of response to TMZ. The demonstration of prolonged survival when TMZ was added to radiotherapy in the European Organisation for Research and Treatment of Cancer 26981/22981/NCIC CE.3 trial has been a breakthrough in the treatment of newly diagnosed glioblastoma. The early preliminary evidence for activity in recurrent malignant gliomas further resulted in a broad evaluation of TMZ for other tumors in neuro-oncology, mainly low-grade gliomas, brain metastases and primary cerebral lymphomas.

Drug Insight: temozolomide as a treatment for malignant glioma—impact of a recent trial

Glioblastoma multiforme is the most common primary brain tumor in adults. Until recently, the standard of care consisted of maximal surgical resection followed by external beam radiotherapy. The role of adjuvant chemotherapy for newly diagnosed glioblastoma has been controversial; most of the numerous randomized phase III trials conducted over the past 40 years have failed to show a statistically significant and clinically meaningful survival advantage for patients randomized to the chemotherapy arm. Consequently, the choices of chemotherapeutics for patients with glioblastoma have been limited, and cytotoxic treatment regimens have usually included a nitrosourea. Temozolomide, a relatively new orally administered methylating agent, has demonstrable activity in glioma. A recent trial conducted under the auspices of the European Organization for the Research and Treatment of Cancer (EORTC) and National Cancer Institute of Canada Clinical Trials Group (NCIC CTG) has defined a role for temozolomide in the initial management of glioblastoma. A companion correlative tumor-biology study has identified epigenetic silencing of the promoter of the gene that encodes MGMT (O6-methylguanine-DNA methyltransferase) in tumor specimens as a strong and independent prognostic factor for survival among patients with a newly diagnosed glioblastoma, as well as a predictor of survival benefit from chemoradiotherapy with temozolomide. This review briefly summarizes the development of temozolomide as a therapy for patients with malignant brain tumors, emphasizing recent trials that have established a new standard of care for patients with glioblastoma and speculating on how these advances might influence future therapeutic investigations for malignant primary brain tumors.

The effect of thermotherapy using magnetic nanoparticles on rat malignant glioma

Thermotherapy using magnetic nanoparticles is a new technique for interstitial hyperthermia and thermoablation based on magnetic field-induced excitation of biocompatible superparamagnetic nanoparticles. To evaluate the potential of this technique for minimally invasive treatment, we carried out a systematic analysis of its effects on experimental glioblastoma multiforme in a rat tumor model. Tumors were induced by implantation of RG-2-cells into the brains of 120 male Fisher rats. Animals were randomly allocated to 10 groups of 12 rats each, including controls. Animals received two thermotherapy treatments following a single intratumoral injection of two different magnetic fluids (dextran- or aminosilane-coated iron-oxide nanoparticles). Treatment was carried out on days four and six after tumor induction using an alternating magnetic field applicator system operating at a frequency of 100 kHz and variable field strength of 0-18 kA/m. The effectiveness of treatment was determined by the survival time of the animals and histopathological examinations of the brain and the tumor.Thermotherapy with aminosilane-coated nanoparticles led up to 4.5-fold prolongation of survival over controls, while the dextran-coated particles did not indicate any advantage. Intratumoral deposition of the aminosilane-coated particles was found to be stable, allowing for serial thermotherapy treatments without repeated injection. Histological and immunohistochemical examinations after treatment revealed large necrotic areas close to particle deposits, a decreased proliferation rate and a reactive astrogliosis adjacent to the tumor.Thus, localized interstitial thermotherapy with magnetic nanoparticles has an antitumoral effect on malignant brain tumors. This method is suitable for clinical use and may be a novel strategy for treating malignant glioma, which cannot be treated successfully today. The optimal treatment schedules and potential combinations with other therapies need to be defined in further studies.

Amplification of genes encoding KIT, PDGFRalpha and VEGFR2 receptor tyrosine kinases is frequent in glioblastoma multiforme

KIT, platelet-derived growth factor receptors (PDGFRs) and vascular endothelial growth factor receptors (VEGFRs) are important clinical targets for tyrosine kinase inhibitors. The frequency of KIT and VEGFR2 amplification in glioblastomas is not known, and few data are available in any other human tumour type. We investigated 43 primary glioblastomas for KIT, VEGFR2, PDGFRA and EGFR amplification using fluorescence in situ hybridization. KIT was amplified in 47% and VEGFR2 in 39% of the glioblastomas, respectively, and PDGFRA in 29%. Thirty-five (81%) of the tumours had either KIT or EGFR amplification. KIT, PDGFRA and VEGFR2 amplifications were strongly associated (p < 0.0001 for each pairwise comparison), suggesting co-amplification, whereas no significant association was found with EGFR amplification. The four secondary glioblastomas arising from pre-existing lower grade astrocytic tumours investigated had KIT amplification but none had EGFR amplification. No mutations were detected with denaturing high-performance liquid chromatography in KIT exons 9, 11, 13 or 17, PDGFRA exons 12 and 18, or EGFR exons 18, 19 or 21. Glioblastomas with KIT, PDGFR or VEGFR2 amplification were associated with similar outcome to other glioblastomas. We conclude that KIT, PDGFRA and VEGFR2 are commonly amplified in primary glioblastoma and that they may also be amplified in secondary glioblastoma. Amplified kinases may be potential targets for tyrosine kinase inhibitor therapy.

Evaluation of the functional diffusion map as an early biomarker of time-to-progression and overall survival in high-grade glioma

Diffuse malignant gliomas, the most common type of brain tumor, carry a dire prognosis and are poorly responsive to initial treatment. The response to treatment is typically evaluated by measurements obtained from radiographic images several months after the start of treatment; therefore, an early biomarker of tumor response would be useful for making early treatment decisions and for prognostic information. Thirty-four patients with malignant glioma were examined by diffusion MRI before treatment and 3 weeks later. These images were coregistered, and differences in tumor-water diffusion values were calculated as functional diffusion maps (fDM), which were correlated with the radiographic response, time-to-progression (TTP), and overall survival (OS). Changes in fDM at 3 weeks were closely associated with the radiographic response at 10 weeks. The percentage of the tumor undergoing a significant change in the diffusion of water (V(T)) was different between patients with progressive disease (PD) vs. stable disease (SD) (P < 0.001). Patients classified as PD by fDM analysis at 3 weeks were found to have a shorter TTP compared with SD (median TTP, 4.3 vs. 7.3 months; P < 0.04). By using fDM, early patient stratification also was correlated with shorter OS in the PD group compared with SD patients (median survival, 8.0 vs. 18.2 months; P < 0.01). On the basis of fDM, tumor assessment provided an early biomarker for response, TTP, and OS in patients with malignant glioma. Further evaluation of this technique is warranted to determine whether it may be useful in the individualization of treatment or evaluation of the response in clinical protocols.

The role of radiosurgery in the management of malignant brain tumors

Stereotactic radiosurgery (SRS) provides the means for creating lesions in deep-seated areas of the brain inaccessible to invasive surgery, using single high doses of focused ionizing radiation, administered using stereotactic guidance. It is a surgical technique designed to produce a specific radiobiological effect within a sharply defined target region in a single treatment session. Its technical application requires a stereotactic coordinate system, highly accurate patient repositioning (usually fixed), and multiple convergent beams of photon radiation. SRS appears to provide no benefit in the upfront treatment of newly diagnosed malignant gliomas but may be used to effectively palliate small well-demarcated volumes of recurrent disease. For selected patients with brain metastases treated with whole-brain radiation therapy (WBRT), the addition of SRS improves median survival. In selected patients with brain metastases, it is also rational to withhold WBRT in favor of radiosurgery alone, with WBRT reserved for salvage without a decrease in median survival time.