Phase II trial of nitrogen mustard, vincristine, and procarbazine in patients with recurrent glioma: North Central Cancer Treatment Group results

Procarbazine, lomustine and vincristine for recurrent high-grade glioma

BACKGROUND

Recurrent high-grade glioma (HGG) carries an extremely poor prognosis. There is no current standard of care or guideline-based recommendations. Nitrosourea-based multidrug chemotherapy or PCV - procarbazine, lomustine (CCNU) and vincristine - is one of the treatment options at recurrence. There has been no meta-analysis which looks at the benefits and harms of PCV chemotherapy in adults with recurrent HGG.

OBJECTIVES

To assess the effectiveness and safety of procarbazine, lomustine, and vincristine (PCV) chemotherapy with other interventions in adults with recurrent high-grade glioma. To investigate whether predefined subgroups of people benefit more or less from chemotherapy.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL Issue 4, 2017), MEDLINE (1946 to 22 May 2017), and Embase (1980 to 22 May 2017). We searched trial registries including the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP; apps.who.int/trialsearch) and the National Institutes of Health (NIH; ClinicalTrials.gov). We searched the reference lists of all identified studies; the electronic table of contents of the Journal of Neuro-Oncology (1983 to 2016) and Neuro-Oncology (1999 to 2016); and conference abstracts from the Society for Neuro-Oncology (SNO) and the American Society of Clinical Oncology (ASCO 2004 to 2016). We also searched unpublished grey literature and other regional databases. There were no language restrictions.

SELECTION CRITERIA

Randomised controlled trials (RCTs), quasi-randomised trials (QRCTs), or controlled clinical trials (CCTs) where PCV was used to treat adults with recurrent HGG. Comparison arm included no chemotherapy, other second line chemotherapy or best supportive care.

DATA COLLECTION AND ANALYSIS

Two review authors extracted the data and undertook a 'Risk of bias' assessment and critical appraisal of the studies.

MAIN RESULTS

We identified two RCTs meeting our inclusion criteria. The two trials tested different comparisons.One RCT included 35 participants and compared PCV with 'eight drugs in one day' multidrug chemotherapy, which is a combination of drugs with different mechanisms of action. Median survival was 6 months for the PCV group and 6.5 months for the 'eight drugs in one day' group. Adverse event outcomes were not graded or quantified. Progression-free survival (PFS) and quality of life (QoL) were not described in the methods and were not an outcome of interest. The sample size in this study was small, which lead to insufficient statistical power to detect clinical differences. According to the GRADE approach we judged the quality of evidence to be low for survival outcome and very low for chemotherapy toxicityThe second multi-institutional RCT included 447 participants and compared PCV with Temozolomide (TMZ). Participants were randomised into three arms to receive PCV, and two different regimens of TMZ in a 2:1:1 ratio at first recurrence. The trial reported a median overall survival of 6.7 months and 7.2 months for the PCV and TMZ group respectively. It reported a PFS of 3.6 months for the PCV group and 4.7 months for the TMZ group. There was no observed difference of effect on overall survival (hazard ratio (HR) 0.91, 95% CI 0.74 to 1.11; P = 0.35) or PFS (HR 0.89, 95% CI 0.73 to 1.08; P = 0.23) in participants receiving PCV or TMZ chemotherapy. The proportion of people with at least one grade 3 or 4 adverse event was not clinically important at 9.2% versus 12.2% in PCV and TMZ arms respectively. Mean QoL scores calculated at baseline, 12 weeks and 24 weeks was 51.9 versus 59.8 favouring TMZ (P = 0.04) which is statistically but not clinically significant and was less than the pre-defined 10 point change for moderate improvement. We judged the GRADE quality of evidence to be moderate for overall survival, PFS, and chemotherapy toxicity and low for QoL.

AUTHORS' CONCLUSIONS

Evidence is based on a single large trial analysis as the other trial was small, with inadequate power to detect survival difference. Chemotherapy-naive patients with HGG at first recurrence when treated with PCV or TMZ have similar survival and time-to-progression outcomes. Adverse events are similar and QoL scores are statistically but not clinically significant between TMZ and PCV. Further RCTs should be conducted with adequate power following CONSORT guidelines with emphasis on QoL outcomes.

Comparison of long-term survival between temozolomide-based chemoradiotherapy and radiotherapy alone for patients with low-grade gliomas after surgical resection

Purpose

This study was designed to compare the survival outcomes of temozolomide-based chemoradiotherapy (TMZ + RT) vs radiotherapy alone (RT-alone) for low-grade gliomas (LGGs) after surgical resection.

Patients and methods

In this retrospective analysis, we reviewed postoperative records of 69 patients with LGGs treated with TMZ + RT (n=31) and RT-alone (n=38) at the Shandong Cancer Hospital Affiliated to Shandong University between June 2011 and December 2013. Patients in the TMZ + RT group were administered 50–100 mg oral TMZ every day until the radiotherapy regimen was completed.

Results

The median follow-up since surgery was 33 months and showed no significant intergroup differences (P=0.06). There were statistically significant intergroup differences in the progression-free survival rate (P=0.037), with 83.9% for TMZ-RT group and 60.5% for RT-alone group. The overall 2-year overall survival (OS) rate was 89.86%. Age distribution (≥45 years and <45 years) and resection margin (complete resection or not) were significantly associated with OS (P=0.03 and P=0.004, respectively).

Conclusion

Although no differences were found in the 2-year OS between the TMZ + RT and RT-alone groups, there was a trend toward increased 2-year progression-free survival in the TMZ + RT group. With better tolerability, concurrent TMZ chemoradiotherapy may be beneficial for postoperative patients with LGGs. Age distribution and surgical margin are likely potential indicators of disease prognosis. The possible differences in long-term survival between the two groups and the links between prognostic factors and long-term survival may be worthy of further investigation.

Radiation plus Procarbazine, CCNU, and Vincristine in Low-Grade Glioma

BACKGROUND

Grade 2 gliomas occur most commonly in young adults and cause progressive neurologic deterioration and premature death. Early results of this trial showed that treatment with procarbazine, lomustine (also called CCNU), and vincristine after radiation therapy at the time of initial diagnosis resulted in longer progression-free survival, but not overall survival, than radiation therapy alone. We now report the long-term results.

METHODS

We included patients with grade 2 astrocytoma, oligoastrocytoma, or oligodendroglioma who were younger than 40 years of age and had undergone subtotal resection or biopsy or who were 40 years of age or older and had undergone biopsy or resection of any of the tumor. Patients were stratified according to age, histologic findings, Karnofsky performance-status score, and presence or absence of contrast enhancement on preoperative images. Patients were randomly assigned to radiation therapy alone or to radiation therapy followed by six cycles of combination chemotherapy.

RESULTS

A total of 251 eligible patients were enrolled from 1998 through 2002. The median follow-up was 11.9 years; 55% of the patients died. Patients who received radiation therapy plus chemotherapy had longer median overall survival than did those who received radiation therapy alone (13.3 vs. 7.8 years; hazard ratio for death, 0.59; P=0.003). The rate of progression-free survival at 10 years was 51% in the group that received radiation therapy plus chemotherapy versus 21% in the group that received radiation therapy alone; the corresponding rates of overall survival at 10 years were 60% and 40%. A Cox model identified receipt of radiation therapy plus chemotherapy and histologic findings of oligodendroglioma as favorable prognostic variables for both progression-free and overall survival.

CONCLUSIONS

In a cohort of patients with grade 2 glioma who were younger than 40 years of age and had undergone subtotal tumor resection or who were 40 years of age or older, progression-free survival and overall survival were longer among those who received combination chemotherapy in addition to radiation therapy than among those who received radiation therapy alone. (Funded by the National Cancer Institute and others; ClinicalTrials.gov number, NCT00003375.).

Phase 2 study of temozolomide-based chemoradiation therapy for high-risk low-grade gliomas: preliminary results of Radiation Therapy Oncology Group 0424

PURPOSE

Radiation Therapy Oncology Group (RTOG) 0424 was a phase 2 study of a high-risk low-grade glioma (LGG) population who were treated with temozolomide (TMZ) and radiation therapy (RT), and outcomes were compared to those of historical controls. This study was designed to detect a 43% increase in median survival time (MST) from 40.5 to 57.9 months and a 20% improvement in 3-year overall survival (OS) rate from 54% to 65% at a 10% significance level (1-sided) and 96% power.

METHODS AND MATERIALS

Patients with LGGs with 3 or more risk factors for recurrence (age ≥40 years, astrocytoma histology, bihemispherical tumor, preoperative tumor diameter of ≥6 cm, or a preoperative neurological function status of >1) were treated with RT (54 Gy in 30 fractions) and concurrent and adjuvant TMZ.

RESULTS

From 2005 to 2009, 129 evaluable patients (75 males and 54 females) were accrued. Median age was 49 years; 91% had a Zubrod score of 0 or 1; and 69%, 25%, and 6% of patients had 3, 4, and 5 risk factors, respectively. Patients had median and minimum follow-up examinations of 4.1 years and 3 years, respectively. The 3-year OS rate was 73.1% (95% confidence interval: 65.3%-80.8%), which was significantly improved compared to that of prespecified historical control values (P<.001). Median survival time has not yet been reached. Three-year progression-free survival was 59.2%. Grades 3 and 4 adverse events occurred in 43% and 10% of patients, respectively. One patient died of herpes encephalitis.

CONCLUSIONS

The 3-year OS rate of 73.1% for RTOG 0424 high-risk LGG patients is higher than that reported for historical controls (P<.001) and the study-hypothesized rate of 65%.

Phase II study of Gleevec plus hydroxyurea in adults with progressive or recurrent low-grade glioma

BACKGROUND

We evaluated the efficacy of imatinib plus hydroxyurea in patients with progressive/recurrent low-grade glioma.

METHODS

A total of 64 patients with recurrent/progressive low-grade glioma were enrolled in this single-center study that stratified patients into astrocytoma and oligodendroglioma cohorts. All patients received 500 mg of hydroxyurea twice a day. Imatinib was administered at 400 mg per day for patients not on enzyme-inducing antiepileptic drugs (EIAEDs) and at 500 mg twice a day if on EIAEDs. The primary endpoint was progression-free survival at 12 months (PFS-12) and secondary endpoints were safety, median progression-free survival, and radiographic response rate.

RESULTS

Thirty-two patients were enrolled into each cohort. Eleven patients (17%) had before radiotherapy and 24 (38%) had received before chemotherapy. The median PFS and PFS-12 were 11 months and 39%, respectively. Outcome did not differ between the histologic cohorts. No patient achieved a radiographic response. The most common grade 3 or greater adverse events were neutropenia (11%), thrombocytopenia (3%), and diarrhea (3%).

CONCLUSIONS

Imatinib plus hydroxyurea was well tolerated among recurrent/progressive LGG patients but this regimen demonstrated negligible antitumor activity.

Efficacy of gamma knife radiosurgery for small-volume recurrent malignant gliomas after initial radical resection

OBJECTIVE

To review the authors' experience with Gamma Knife radiosurgery (GKR) for small recurrent high-grade gliomas (HGGs) following prior radical resection, external-beam radiation therapy (EBRT), and chemotherapy with temozolomide (TMZ).

METHODS

The authors retrospectively analyzed 26 consecutive adults (9 women and 17 men; median age 60.4 years; Karnofsky Performance Status [KPS]≥70) who underwent GKR for recurrent HGGs from 2004-2009. Median lesion volume was 1.22 cc, and median treatment dose was 15 Gy. Pathology included glioblastoma multiforme (GBM; n=16), anaplastic astrocytoma (AA; n=5), and anaplastic mixed oligoastrocytoma (AMOA; n=5). Two patients lost to follow-up were excluded from radiographic outcome analyses.

RESULTS

Median overall survival (OS) for the entire cohort from the time of GKR was 13.5 months. Values for 12-month actuarial survival from time of GKR for GBM, AMOA, and AA were 37%, 20% and 80%. Local failure occurred in 9 patients (37.5%) at a median time of 5.8 months, and 18 patients (75%) experienced distant progression at a median of 4.8 months. Complications included radiation necrosis in two patients and transient worsening of hemiparesis in one patient. Multivariate hazard ratio (HR) analysis showed KPS 90 or greater, smaller tumor volumes, and increased time to recurrence after resection to be associated with longer OS following GKR.

CONCLUSIONS

GKR provided good local tumor control in this group of clinically stable and predominantly high-functioning patients with small recurrent HGGs after radical resection. Meaningful survival times after GKR were seen. GKR can be considered for selected patients with recurrent HGGs.

Is there a place for radiotherapy in low-grade gliomas?

The optimal management of supratentorial low-grade glioma remains controversial, and only limited definitive data is available to guide recommendations. Treatment decisions have to take into account both the management of symptoms and of tumour control, and must balance the benefits against the potential for treatment-related complications. Overall outcome is more dependent on patient and tumour-related characteristics such as age, tumour grade, histology and neurological function than treatment. From the pooled analysis of 2 randomized EORTC trials a prognostic score has been derived, median survival is varying from 3.2 to 7.8 years. Radiation therapy is usually the primary treatment modality; however its benefit on initial tumour control may be outweighed by potential late toxicity. To date only 4 large randomized trials in patients with low-grade glioma have been reported. It allows concluding that early radiotherapy does not improve overall survival and supports an initially expectative approach. Similarly, higher radiation doses above 45-50 Gy (fractions of 1.8-2.0 Gy) do not confer a better outcome but may be associated with increased toxicity. The adjuvant use of PCV-chemotherapy in high-risk patients also failed to improve progression-free and overall survival. An ongoing large randomized EORTC/NCIC trial is investigating the primary treatment with temozolomide chemotherapy versus standard radiotherapy in patients "at need for treatment". Tumour material will be collected in all patients, which ultimately may allow identifying on a molecular basis patients for whom one or another treatment strategy may fit best. Irrespective of new chemotherapeutic agents, radiotherapy is also evolving. Highly conformal techniques based on modern imaging as co-registered MRI scans, limiting the amount of normal tissue irradiated without compromising tumour control, will be the future approach in order to reduce neurotoxicity.

Revisiting anaplastic astrocytomas I: an expansive growth pattern is associated with a better prognosis

PURPOSE

To study whether anaplastic astrocytomas that are nonenhancing and/or well-circumscribed (expansive) are associated with a better prognosis.

MATERIALS AND METHODS

We retrospectively identified 59 patients with pathologically confirmed World Health Organizaiton (WHO) grade III anaplastic astrocytoma who underwent craniotomy at our institution from 1995 through 2006. We assessed prognostic variables including age, enhancement (EAA-34 patients) vs. nonenhancement (NEAA-25 patients), MR growth patterns (expansive [28 patients] vs. mixed/infiltrative [31 patients]), recursive partitioning analysis (RPA) class, resection extent, and addition of chemotherapy. Primary outcome measure was survival.

RESULTS

Kaplan-Meier curves showed improved survival in NEAA, expansive tumors, and RPA 1 class patients. Within RPA class I patients, expansive growth pattern remained a significant advantage in survival time. Examining extent of resection also showed that patients with gross total resections (GTR) had a better prognosis. A multivariate (Cox proportional hazards) analysis showed that patient age and expansive tumor phenotype affected outcome, whereas RPA class, enhancement, and GTR did not.

CONCLUSION

Circumscribed growth in histologically proven anaplastic astrocytoma, which has not been emphasized in past studies, has a considerable survival advantage.

The relationship between six-month progression-free survival and 12-month overall survival end points for phase II trials in patients with glioblastoma multiforme

Common end points for phase II trials in patients with glioblastoma multiforme (GBM) are six-month progression-free survival (PFS6) and 12-month overall survival (OS12). OS12 can be accurately measured but may be confounded with subsequent therapies upon progression, whereas the converse is true for PFS6. Our goal was to assess the relationship between these end points separately for phase II trials in patients with newly diagnosed GBM and patients with recurrent GBM. Data were pooled from 11 North Central Cancer Treatment Group trials for patients with newly diagnosed GBM (n = 1348). All patients received radiotherapy and pharmaceutical therapy (before, during, or after radiotherapy). Data were pooled from 16 trials that used various pharmaceuticals in treating patients for recurrent GBM (n = 345). All trial regimens were declared nonefficacious by predefined criteria. Overall per-patient concordance was estimated with a kappa statistic. The relationship between OS12 and PFS6 across study arms was assessed by weighted linear regression and Pearson's correlation. Simulation was used to determine the agreement of study outcomes when using PFS6 versus OS12 end points. Cox models with progression status as a time-dependent variable and Kaplan-Meier estimators were used to ascertain the association between progression-free survival status and overall survival. At present, 97% of the patients with newly diagnosed GBM and 95% of those with recurrent GBM have died. The PFS6 and OS12 were 43% and 41%, respectively, for patients with newly diagnosed disease and 9% and 14% for patients with recurrent disease. There was only moderate concordance between the end points on both the patient level and the study level. For the simulation studies, we established phase II efficacy criteria for each end point by using the pooled estimates of OS12 (PFS6) as historical controls. The study decisions made using PFS6 and OS12 were in agreement 88% and 90% of the time for the trials of newly diagnosed and recurrent disease, respectively. Finally, there was a strong association between progression-free survival status and overall survival. PFS6 seems to be a reasonable end point for phase II trials in patients with recurrent glioblastoma.

The effect of sequential radiochemotherapy in preirradiated malignant gliomas in a phase II study

The optimum treatment strategy for recurrent high-grade gliomas in preirradiated areas remains undefined. This prospective non-randomized phase II study was undertaken to evaluate a radiochemotherapy protocol against this disease. Fourteen patients (median age 61 years) were treated according to a standardized treatment protocol consisting of sequential radiochemotherapy. The chemotherapy (temozolomide) was carried out over a duration of five sequential days (Mon.-Fri.) with a dose of 200 mg/m2/d. Chemotherapy courses were repeated in 4-week intervals (days 1, 29, 57, etc.) until clinical progression. Radiotherapy with 30 Gy over 3 weeks (5 x 2 Gy/week) was interposed between the first two chemotherapy courses (days 8-26). Eleven/fourteen patients had no acute side effects. One patient suffered from acute thrombocytopenia/leucocytopenia, one patient developed mental degradation (treatment stopped at 24 Gy) and another severe cephalgia. Until now, 10 out of 14 patients have died due to disease progression. Median survival (Kaplan-Meier method) amounts to 30 weeks with a 6-months progression-free survival of 30%. Four of fourteen patients are still alive 8, 10, 11 and 12 months after therapy. Late treatment toxicities have not been observed so far. The reported radiochemotherapy protocol seems to be feasible for these patients with only few treatment alternatives and does not lead to a remarkable increase in acute toxicity. Palliative and survival benefits are modest. Evaluation of late toxicities needs further investigations.

Temozolomide in the treatment of recurrent malignant glioma

BACKGROUND

Options for chemotherapy at the time of recurrence in patients with malignant glioma are limited. The authors describe the efficacy and safety results of their institution's open-label, compassionate-use protocol of temozolomide for patients with recurrent malignant glioma.

METHODS

Patients with recurrent malignant glioma at any time during recurrence were treated with oral temozolomide at a dose of 150 mg/m2 per day on a 5-day schedule every 28 days. If this dose was tolerated, then escalation to 200 mg/m2 was allowed. Clinical evaluations and assessments of tumor response were performed every 2 months. All patients or their surrogates signed approved Institutional Review Board consent forms.

RESULTS

Among 213 patients who were treated, 33% had Grade 3 tumors, and 67% had Grade 4 tumors. The overall objective response rate was 16% in both of these patient groups; and an additional 51% and 30% of patients with Grade 3 and Grade 4 tumors, respectively, had stable disease as their best response. The 6-month progression-free survival rates were 41% and 18% for patients with Grade 3 and Grade 4 tumors, respectively. The median survival was 49 weeks for patients with Grade 3 tumors and 32 weeks for patients with Grade 4 tumors. The major toxicity was hematologic toxicity. In multivariate analysis, the Karnofsky performance score was a significant predictor of survival for patients with Grade 4 tumors.

CONCLUSIONS

Temozolomide was well tolerated in patients with recurrent malignant glioma and had modest efficacy, even at the time of multiple recurrences.

Second-line chemotherapy with dacarbazine and fotemustine in nitrosourea-pretreated patients with recurrent glioblastoma multiforme

The aim of this study was to assess the efficacy and toxicity of a combination of dacarbazine (D) and fotemustine (F) administered to a homogenous group of patients with recurrent or progressive glioblastoma multiforme (GBM). Thirty-one patients with computed tomography or magnetic resonance imaging scan evidence of recurrent or progressive GBM after first-line chemotherapy with nitrosoureas as well as radiation therapy were given a combination of D (200 mg/m2) and F (100 mg/m2). At 30 min after termination of D administration, F was given over 60 min. Treatment was performed in an outpatient setting every 21 days. A total of 140 cycles (range 1-12 cycles; median 4 cycles) was administered. One partial response (3%) lasting for 11 weeks was observed. Sixteen (52%) patients reached stable disease lasting between 7 and 94 weeks. Median survival from start of the D/F combination was 45 (range 10-150) weeks. Median time to progression was 17 (3-101) weeks for all patients. Major toxicity was myelosuppression resulting in exclusion from study in seven (23%) patients [due to thrombocytopenia common toxicity criteria (CTC) grade 2 persisting longer than 3 weeks in three patients, due to thrombocytopenia CTC grade >/=3 in three and due to leukopenia CTC grade 3 in one patient]. No other toxicity than alopecia occurred. We conclude that the D/F combination is a well-tolerated second-line regimen and can be administered in a complete outpatient setting. D/F shows efficacy even in nitrosourea-pretreated patients and justifies further investigation.

Novel chemotherapeutic approaches to brain tumors

In reviewing the numerous investigational drug trials for patients with anaplastic gliomas over the past 20 years, it would be fair to say that there have been more than a few disappointments and that the real impact of many of these therapies on patients' duration and quality of survival has been minor at best. It is also fair to state that there has been progress in developing new types of chemotherapy and other agents, in devising new treatment strategies, and in gaining a deeper understanding of the problems that must be overcome to treat patients with anaplastic gliomas successfully. The past several years have seen the realization that oligodendroglioma, primary CNS lymphoma, and medulloblastoma are sensitive to chemotherapy treatments. It is hoped that future studies will delineate better the optimal use of chemotherapy for these tumors.

High concentration of Daunorubicin and Daunorubicinol in human malignant astrocytomas after systemic administration of liposomal Daunorubicin

The value of chemotherapy in patients with malignant astrocytoma remains controversial. In our laboratories in vitro experiments with organotypic spheroid cultures showed superior effectiveness of anthracyclines. Systemic administration did not provide in therapeutic concentrations so far. Because recent studies on Daunorubicin in liposomes in the treatment of Kaposi sarcoma have shown effectiveness with diminished systemic toxicity, we administered intravenously a single dose of Daunorubicin in liposomes in eight patients at different intervals prior to surgery (12-50 h). In samples taken from tumor, tumor-edge and where possible from adjacent brain, the levels of Daunorubicin and its active metabolite Daunorubicinol were assessed with high performance liquid chromatography. Here we report that high concentrations of Daunorubicin and Daunorubicinol were found in malignant gliomas after systemic administration of liposomal Daunorubicin.

Multicenter phase II trial of temozolomide in patients with glioblastoma multiforme at first relapse

BACKGROUND

Recurrent glioblastoma multiforme (GBM) is resistant to most therapeutic endeavors, with low response rates and survival rarely exceeding six months. There are no clearly established chemotherapeutic regimens and the aim of treatment is palliation with improvement in the quality of life.

PATIENTS AND METHODS

We report an open-label, uncontrolled, multicenter phase II trial of temozolomide in 138 patients (intent-to-treat [ITT] population) with glioblastoma multiforme at first relapse and a Karnofsky performance status (KPS) > or = 70. One hundred twenty-eight patients were histologically confirmed with GBM or gliosarcoma (GS) by independent central review. Chemotherapy-naïve patients were treated with temozolomide 200 mg/m2/day orally for the first five days of a 28-day cycle. Patients previously treated with nitrosourea-containing adjuvant chemotherapy received 150 mg/m2/day for the first five days of a 28-day cycle. In the absence of grade 3 or 4 toxicity, patients on the 150 mg/m2 dose schedule were eligible for a 200 mg/m2 dose on the next cycle.

RESULTS

The primary endpoint was six-month progression-free survival assessed with strict radiological and clinical criteria. Secondary endpoints included radiological response and Health-related Quality of Life (HQL). Progression-free survival at six months was 18% (95% confidence interval (CI): 11%-26%) for the eligible-histology population. Median progression-free survival and median overall survival were 2.1 months and 5.4 months, respectively. The six-month survival rate was 46%. The objective response rate (complete response and partial response) determined by independent central review of gadolinium-enhanced magnetic resonance imaging (MRI) scans was 8% for both the ITT and eligible-histology populations, with an additional 43% and 45% of patients, respectively, having stable disease (SD). Objectively assessed response and maintenance of a progression-free status were both associated with HQL benefits (characterized by improvements over baseline in HQL domains). Temozolomide had an acceptable safety profile, with only 9% of therapy cycles requiring a dose reduction due to thrombocytopenia. There was no evidence of cumulative hematologic toxicity.

CONCLUSIONS

Temozolomide demonstrated modest clinical efficacy, with an acceptable safety profile and measurable improvement in quality of life in patients with recurrent GBM. The use of this drug should be explored further in an adjuvant setting and in combination with other agents.

A comparison of treatment results for recurrent malignant gliomas

Retreatment of malignant gliomas may be performed with palliative intent after careful consideration of the risks and benefits, and with special regards to iatrogenic neurotoxicity and quality of life (QOL). This review compares studies of several retreatment strategies (published between 1987 and 2000) based on the quality of their evidence. Depending on both established prognostic factors and previous treatment, individually tailored retreatment strategies are possible. In all studies that included a multivariate analysis of prognostic factors, performance status was the most important. So far, predictive factors for response, which might facilitate patient selection, have not been unequivocally defined. In terms of QOL, single-agent chemotherapy (temozolomide, nitrosoureas, platinum and taxane derivatives) may offer a better therapeutic ratio than polychemotherapy. For glioblastoma multiforme, progression-free survival and QOL were more favourable after temozolomide than procarbazine (level 1 evidence). The survival of patients after various radiotherapy techniques is broadly similar. However, considerable toxicity is associated with radiosurgery or brachytherapy. Fractionated stereotactic radiotherapy plus radio-sensitizing cytostatic agents has shown promising initial results in small groups of selected patients and awaits further evaluation. Level 2 evidence derived from non-randomized studies does not suggest a substantial prolongation of survival by re-resection as compared with chemotherapy or radiotherapy alone. Level 1 evidence derived from a randomized trial suggests that application of BCNU polymers significantly improves the outcome after re-resection. However, most studies reported median survival in the range of only 25-35 weeks, thereby emphasizing the need for the development and clinical evaluation of new innovative treatment approaches.

New chemotherapy options for the treatment of malignant gliomas

Chemotherapy remains part of the treatment triad that includes surgery and radiation therapy for the management of malignant gliomas. In recent years there has been an increased understanding of the molecular pathways of malignant transformation. Based on this research, new drugs have been evaluated, with specific cellular targets in mind that can be modified or inhibited. Many of these agents are now being tested in phase I and II clinical trials and have shown some promising results. Clearly, not all patients with malignant gliomas respond equally to chemotherapy. Recent evidence suggests that certain molecular markers may predict chemosensitivity in some tumor types, particularly anaplastic oligodendroglioma. This article reviews recent trends in the use of chemotherapy and clinical trials of new therapies for adults with malignant gliomas.