Placebo-controlled trial of safety and efficacy of intraoperative controlled delivery by biodegradable polymers of chemotherapy for recurrent gliomas. The Polymer-brain Tumor Treatment Group

Self-assembling doxorubicin silk hydrogels for the focal treatment of primary breast cancer

Standard care for early stage breast cancer includes tumor resection and local radiotherapy to achieve long-term remission. Systemic chemotherapy provides only low locoregional control of the disease; therefore, we describe self-assembling silk hydrogels that can retain and then deliver doxorubicin locally. Self-assembling silk hydrogels show no swelling, are readily loaded with doxorubicin under aqueous conditions and release drug over 4 weeks in amounts that can be fine-tuned by varying the silk content. Following successful in vitro studies, locally injected silk hydrogels loaded with doxorubicin show excellent antitumor response in mice, outperforming the equivalent amount of doxorubicin delivered intravenously. In addition to reducing primary tumor growth, doxorubicin-loaded silk hydrogels reduce metastatic spread and are well tolerated in vivo. Thus, silk hydrogels are well suited for the local delivery of chemotherapy and provide a promising approach to improve locoregional control of breast cancer.

Sustainable release of carmustine from biodegradable poly[((D,L))-lactide-co-glycolide] nanofibrous membranes in the cerebral cavity: in vitro and in vivo studies

OBJECTIVE

Glioblastoma multiforme (GBM) is the most common and most aggressive malignant primary brain tumor in humans. The only interstitial chemotherapy pharmaceutical approved to date for GBM treatment is the Gliadel® wafer. Despite the safety and efficacy of this approach that have been demonstrated in patients undergoing resection of both newly diagnosed and recurrent malignant gliomas, the wafer provides an effective release of the anticancer 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU) for only 5 days.

METHODS

In this study, the authors developed biodegradable poly[(d,l)-lactide-co-glycolide] nanofibrous membranes via electrospinning that provided a sustained release of BCNU. An elution method and a HPLC assay were employed to characterize the in vitro and in vivo release behaviors of pharmaceuticals from the electrospun membranes.

RESULTS

The experimental results show that the biodegradable, nanofibrous membranes released high concentrations of BCNU for more than 6 weeks in the cerebral cavity of rats. Furthermore, the membranes can better conform to the geometry of the brain tissue and can cover more completely the tissue after the removal of tumors, achieving better drug transport without interfering with the normal function of the brain. Histological examination showed no obvious inflammation reactions of the brain tissues.

CONCLUSION

Adopting the electrospinning technique will help in manufacturing biodegradable, nanofibrous membranes for the long-term deliveries of various anticancer drugs in the cerebral cavity, which will further enhance the therapeutic efficacy of GBM treatment.

Standards of care for treatment of recurrent glioblastoma--are we there yet?

Newly diagnosed glioblastoma is now commonly treated with surgery, if feasible, or biopsy, followed by radiation plus concomitant and adjuvant temozolomide. The treatment of recurrent glioblastoma continues to be a moving target as new therapeutic principles enrich the standards of care for newly diagnosed disease. We reviewed PubMed and American Society of Clinical Oncology abstracts from January 2006 to January 2012 to identify clinical trials investigating the treatment of recurrent or progressive glioblastoma with nitrosoureas, temozolomide, bevacizumab, and/or combinations of these agents. At recurrence, a minority of patients are eligible for second surgery or reirradiation, based on appropriate patient selection. In temozolomide-pretreated patients, progression-free survival rates at 6 months of 20%-30% may be achieved either with nitrosoureas, temozolomide in various dosing regimens, or bevacizumab. Combination regimens among these agents or with other drugs have not produced evidence for superior activity but commonly produce more toxicity. More research is needed to better define patient profiles that predict benefit from the limited therapeutic options available after the current standard of care has failed.

Bevacizumab as first-line therapy for glioblastoma

Bevacizumab is a monoclonal antibody that binds and neutralizes VEGF. Bevacizumab is currently indicated as monotherapy for recurrent glioblastoma. Recent data from Phase II trials of bevacizumab as first-line therapy for glioblastoma have been promising, and have led to two Phase III trials evaluating the use of bevacizumab as first-line therapy when combined with radiation and temozolomide. Potential complications relating to interpretation of the results of these Phase III studies include the crossover use of bevacizumab upon recurrence in the placebo arm. Recently published single-arm evaluations of adding bevacizumab to standard first-line therapy in glioblastoma multiforme have shown an improvement in progression-free survival and overall survival when compared with historical controls obtained prior to widespread use of bevacizumab in recurrent glioblastoma multiforme. When these data are compared with more contemporary studies from the bevacizumab era, the improvement in progression-free survival seems to be maintained but the impact on overall survival with first-line bevacizumab therapy seems less clear. Bevacizumab therapy alters the imaging characteristics of glioblastoma, and new criteria have been established to assess treatment response and progression in the setting of widespread bevacizumab use.

Implanted carmustine wafers followed by concomitant radiochemotherapy to treat newly diagnosed malignant gliomas: prospective, observational, multicenter study on 92 cases

OBJECTIVES

Study the feasibility and effectiveness of a treatment associated surgery, intraoperative chemotherapy (carmustine wafers), and concomitant radiochemotherapy (temozolomide) for the management of newly diagnosed, high-grade gliomas.

METHODS

Prospective multicenter study conducted in 17 French centers with a total of 92 patients with newly diagnosed malignant glioma treated by surgery, implanted Carmustine wafers (Gliadel(®)) followed by concomitant radiochemotherapy by temozolomide (Temodar(®)). Clinical, imaging, and survival data were collected to study toxicity-induced adverse events and efficacy.

RESULTS

A total of 20.6 % presented with adverse events during surgery, potentially attributable to carmustine, including 5 severe infections. Afterwards, 37.2 % of patients showed adverse events during radiochemotherapy and 40 % during adjuvant chemotherapy by temozolomide. We report a 10.5-month, median, progression-free survival and an 18.8-month median overall survival. No significant statistical difference was observed according to age, Karnofsky Performance Scale, or grade of the tumor. A prognostic difference at the limit of the significance threshold was observed according to the extent of the resection.

CONCLUSIONS

Multimodal treatment associating implanted carmustine chemotherapy and concomitant radiochemotherapy with temozolomide seems to yield better survival rates than those usually described when carmustine or temozolomide are used alone independently from one another. These interesting results were obtained without increased adverse events and would need to be validated during a phase 3 study.

Safety and efficacy of concomitant chemotherapeutic wafers and iodine-125 seeds for recurrent glioblastoma

Background:

Patients with recurrent malignant gliomas have a uniformly poor prognosis. However, further treatment is often warranted at the time of recurrence. Low-activity implanted brachytherapeutic devices, such as iodine-125 seeds, and implantable chemotherapeutic devices such as 1, 3-bis (2-chloroethyl)-nitrosourea (BCNU) impregnated polymer wafers (Gliadel^®) have been shown to be safe and modestly effective, but a comparison of combination therapy versus Gliadel^® implantation alone has not been performed.

Methods:

We retrospectively examined 24 patients following re-resection of recurrent glioblastoma, with 17 patients undergoing implantation of both Gliadel^® and iodine-125 seeds, and 7 patients undergoing implantation of Gliadel^® only. Outcomes examined included adverse events, survival after re-resection (SAR), and time to tumor progression after re-resection (PAR).

Results:

Implantation of both Gliadel^® and low activity iodine-125 seeds is safe with only two wound infections noted, a complication rate comparable to previous reports. The combination appears to confer a median SAR benefit if the activity per tumor resection volume exceeds 0.8 mCi/mL (60 versus 31 weeks, P = 0.02), and this benefit remained significant on multivariate analysis (HR =0.26 [CI:0.07-0.93], P = 0.03). Gross total resection of tumor was also significantly associated with longer time to PAR (HR =5.4 [CI: 1.13-26.0], P = 0.03).

Conclusions:

The concomitant use of Gliadel^® and low activity iodine-125 seeds following re-resection of recurrent glioblastoma is safe. Our study demonstrated a significant benefit in SAR if the iodine-125 activity per tumor volume is greater than 0.8 mCi/mL. While our sample size is small, our results are in agreement with previous studies demonstrating the efficacy of combination treatment.

SEOM guideline for the treatment of malignant glioma

High-grade gliomas are an infrequent disease diagnosed usually in the fifth or sixth decade. Careful histopathological diagnosis is essential because tumour grade and type condition the treatment. Magnetic resonance with gadolinium is considered the standard radiologic exploration and should be followed by tissue sampling. Treatment of these patients should be decided in a multidisciplinary committee. Surgery, radiotherapy and chemotherapy are the basis of patients' treatment, with the best results obtained when the three of them can be used.

Polifeprosan 20, 3.85% carmustine slow-release wafer in malignant glioma: evidence for role in era of standard adjuvant temozolomide

The Polifeprosan 20 with carmustine (BCNU, bis-chloroethylnitrosourea, Gliadel^®) polymer implant wafer is a biodegradable compound containing 3.85% carmustine which slowly degrades to release carmustine and protects it from exposure to water with resultant hydrolysis until the time of release. The carmustine implant wafer was demonstrated to improve survival in blinded placebo-controlled trials in selected patients with newly diagnosed or recurrent malignant glioma, with little increased risk of adverse events. Based on these trials and other supporting data, US and European regulatory authorities granted approval for its use in recurrent and newly diagnosed malignant glioma, and it remains the only approved local treatment. The preclinical and clinical data suggest that it is optimally utilized primarily in the proportion of patients who may have total or near total removal of gross tumor. The aim of this work was to review the evidence for the use of carmustine implants in the management of malignant astrocytoma (World Health Organization grades III and IV), including newly diagnosed and recurrent disease, especially in the setting of a standard of care that has changed since the randomized trials were completed. Therapy has evolved such that patients now generally receive temozolomide chemotherapy during and after radiotherapy treatment. For patients undergoing repeat resection for malignant glioma, a randomized, blinded, placebo-controlled trial demonstrated a median survival for 110 patients who received carmustine polymers of 31 weeks compared with 23 weeks for 122 patients who only received placebo polymers. The benefit achieved statistical significance only on analysis adjusting for prognostic factors rather than for the randomized groups as a whole (hazard ratio = 0.67, P = 0.006). A blinded, placebo-controlled trial has also been performed for carmustine implant placement in newly diagnosed patients prior to standard radiotherapy. Median survival was improved from 11.6 to 13.9 months (P = 0.03), with a 29% reduction in the risk of death. When patients with glioblastoma multiforme alone were analyzed, the median survival improved from 11.4 to 13.5 months, but this improvement was not statistically significant. When a Cox’s proportional hazard model was utilized to account for other potential prognostic factors, there was a significant 31% reduction in the risk of death (P = 0.04) in this subgroup. Data from other small reports support these results and confirm that the incidence of adverse events does not appear to be increased meaningfully. Given the poor prognosis without possibility of cure, these benefits from a treatment with a favorable safety profile were considered meaningful. There is randomized evidence to support the use of carmustine wafers placed during resection of recurrent disease. Therefore, although there is limited specific evidence, this treatment is likely to be efficacious in an environment when nearly all patients receive temozolomide as part of initial management. Given that half of the patients in the randomized trial assessing the value of carmustine implants in recurrent disease had received prior chemotherapy, it is likely that this remains a valuable treatment at the time of repeat resection, even after temozolomide. There are data from multiple reports to support safety. Although there is randomized evidence to support the use of this therapy in newly diagnosed patients who will receive radiotherapy alone, it is now standard to administer both adjuvant temozolomide and radiotherapy. There are survival outcome reports for small cohorts of patients receiving temozolomide with radiotherapy, but this information is not sufficient to support firm recommendations. Based on the rationale and evidence of safety, this approach appears to be a reasonable option as more information is acquired. Available data support the safety of using carmustine wafers in this circumstance, although special attention to surgical guidelines for implanting the wafers is warranted.

Multiple resections for patients with glioblastoma: prolonging survival

OBJECT

Glioblastoma is the most common and aggressive type of primary brain tumor in adults. These tumors recur regardless of intervention. This propensity to recur despite aggressive therapies has made many perceive that repeated resections have little utility. The goal of this study was to evaluate if patients who underwent repeat resections experienced improved survival as compared with patients with fewer numbers of resections, and whether the number of resections was an independent predictor of prolonged survival.

METHODS

The records of adult patients who underwent surgery for an intracranial primary glioblastoma at an academic tertiary-care institution between 1997 and 2007 were retrospectively reviewed. Multivariate proportionalhazards regression analysis was used to identify an association between glioblastoma resection number and survival after controlling for factors known to be associated with survival, such as age, functional status, periventricular location, extent of resection, and adjuvant therapy. Survival as a function of time was plotted using the Kaplan-Meier method, and survival rates were compared using log-rank analysis.

RESULTS

Five hundred seventy-eight patients with primary glioblastoma met the inclusion/exclusion criteria. At last follow-up, 354, 168, 41, and 15 patients underwent 1, 2, 3, or 4 resections, respectively. The median survival for patients who underwent 1, 2, 3, and 4 resections was 6.8, 15.5, 22.4, and 26.6 months (p < 0.05), respectively. In multivariate analysis, patients who underwent only 1 resection experienced shortened survival (relative risk [RR] 3.400, 95% CI 2.423-4.774; p < 0.0001) as compared with patients who underwent 2 (RR 0.688, 95% CI 0.525-0.898; p = 0.0006), 3 (RR 0.614, 95% CI 0.388-0.929; p = 0.02), or 4 (RR 0.600, 95% CI 0.238-0.853; p = 0.01) resections. These results were verified in a case-control evaluation, controlling for age, neurological function, periventricular tumor location, extent of resection, and adjuvant therapy. Patients who underwent 1, 2, or 3 resections had a median survival of 4.5, 16.2, and 24.4 months, respectively (p < 0.05). Additionally, the risk of infections or iatrogenic deficits did not increase with repeated resections in this patient population (p > 0.05).

CONCLUSIONS

Patients with glioblastoma will inevitably experience tumor recurrence. The present study shows that patients with recurrent glioblastoma can have improved survival with repeated resections. The findings of this study, however, may be limited by an intrinsic bias associated with patient selection. The authors attempted to minimize these biases by using strict inclusion criteria, multivariate analyses, and case-control evaluation.

Canadian recommendations for the treatment of recurrent or progressive glioblastoma multiforme

Recommendation 1: Multidisciplinary ApproachTo optimize treatment outcomes, the management of patients with recurrent glioblastoma should be individualized and should involve a multidisciplinary team approach, including neurosurgery, neuropathology, radiation oncology, neuro-oncology, and allied health professions.Recommendation 2: ImagingThe standard imaging modality for assessment of recurrent glioblastoma is Gd-enhanced magnetic resonance imaging (mri). Tumour recurrence should be assessed according to the criteria set out by the Response Assessment in Neuro-Oncology Working Group. The optimal timing and frequency of mri after chemoradiation and adjunctive therapy have not been established.Recommendation 3: Pseudo-progressionProgression observed by mri after chemoradiation can be pseudo-progression. Accordingly, treated patients should not be classified as having progressive disease by Gd-enhancing mri within the first 12 weeks after the end of radiotherapy unless new enhancement is observed outside the radiotherapy field or viable tumour is confirmed by pathology at the time of a required re-operation. Adjuvant temozolomide should be continued and follow-up imaging obtained.Recommendation 4: Repeat SurgerySurgery can play a role in providing symptom relief and confirming tumour recurrence, pseudo-progression, or radiation necrosis. However, before surgical intervention, it is essential to clearly define treatment goals and the expected impact on prognosis and the patient's quality of life. In the absence of level 1 evidence, the decision to re-operate should be made according to individual circumstances, in consultation with the multidisciplinary team and the patient.Recommendation 5: Re-irradiationRe-irradiation is seldom recommended, but can be considered in carefully selected cases of recurrent glioblastoma.Recommendation 6: Systemic TherapyClinical trials, when available, should be offered to all eligible patients. In the absence of a trial, systemic therapy, including temozolomide rechallenge or anti-angiogenic therapy, may be considered. Combination therapy is still experimental; optimal drug combinations and sequencing have not been established.

Response assessment of bevacizumab in patients with recurrent malignant glioma using [18F]Fluoroethyl-L-tyrosine PET in comparison to MRI

PURPOSE

To investigate prospectively the potential of O-(2-[(18)F]fluoroethyl)-L-tyrosine ((18)F-FET) PET in comparison to MRI for the assessment of the response of patients with recurrent high-grade glioma (rHGG) to antiangiogenic treatment.

METHODS

Ten patients with rHGG were treated biweekly with bevacizumab/irinotecan (BEV/IR). MR images and dynamic (18)F-FET PET scans were obtained at baseline and at follow-up after the start of treatment (median 4.9 weeks). Using MRI treatment response was evaluated according to RANO (Response Assessment in Neuro-Oncology) criteria. For (18)F-FET PET evaluation, a reduction >45 % of the metabolically active tumour volume was considered as a treatment response, with the metabolically active tumour being defined as a tumour-to-brain ratio (TBR) of ≥1.6. The results of the treatment assessments were related to progression-free survival (PFS) and overall survival (OS). For further evaluation of PET data, maximum and mean TBR were calculated using region-of-interest analysis at baseline and at follow-up. Additionally, (18)F-FET uptake kinetic studies were performed at baseline and at follow-up in all patients. Time-activity curves were generated and the times to peak (TTP) uptake (in minutes from the beginning of the dynamic acquisition to the maximum uptake) were calculated.

RESULTS

At follow-up, MRI showed a complete response according to RANO criteria in one of the ten patients (10 %), a partial response in five patients (50 %), and stable disease in four patients (40 %). Thus, MRI did not detect tumour progression. In contrast, (18)F-FET PET revealed six metabolic responders (60 %) and four nonresponders (40 %). In the univariate survival analyses, a response detected by (18)F-FET PET predicted a significantly longer PFS (median PFS, 9 vs. 3 months; P = 0.001) and OS (median OS 23.0 months vs. 3.5 months; P = 0.001). Furthermore, in four patients (40 %), diagnosis according to RANO criteria and by (18)F-FET PET was discordant. In these patients, PET was able to detect tumour progression earlier than MRI (median time benefit 10.5 weeks; range 6-12 weeks). At baseline and at follow-up, in nonresponders TTP was significantly shorter than in responders (baseline TTP 10 ± 8 min vs. 35 ± 9 min; P = 0.002; follow-up TTP 23 ± 9 min vs. 39 ± 8 min; P = 0.02). Additionally, at baseline a kinetic pattern characterized by an early peak of (18)F-FET uptake followed by a constant descent was more frequently observed in the nonresponders (P = 0.018).

CONCLUSION

Both standard and kinetic imaging parameters derived from(18)F-FET PET seem to predict BEV/IR treatment failure and thus contribute important additional information for clinical management over and above the information obtained by MRI response assessment based on RANO criteria.

Bevacizumab is an active agent for recurrent high-grade glioma, but do we need randomized controlled trials?

High-grade gliomas (HGGs), including glioblastoma, are a heterogeneous group of primary brain tumors, associated with devastating neurological sequelae and limited survival. In 2005, a randomized phase III study established postoperative radiotherapy and temozolomide as the standard of care for patients with resected, newly diagnosed glioblastoma. Despite this progress, almost all patients relapse and therapeutic options in the recurrent setting are limited. The optimum approach for recurrent HGG is challenging because of tumor resistance and the worsening performance status of the patients. As glioblastoma is a highly vascular tumor and has high levels of vascular endothelial growth factor, there has been interest in the use of the vascular endothelial growth factor targeting, monoclonal antibody bevacizumab. In a series of phase II studies, bevacizumab alone or with irinotecan showed improvements in tumor response, disease control, and survival compared with historical controls. These results led to the licensing of bevacizumab for glioblastoma in the USA, but a contrasting view was adopted by the European Medicines Agency, because of (deemed) modest response rates and lack of direct comparisons with other agents. Against this background, Gil and colleagues conducted a retrospective review of 130 patients with recurrent HGG treated with bevacizumab and irinotecan and showed an encouraging median progression-free survival of 5.1 months (95% confidence interval, 4.4-5.9) and a median overall survival of 9.0 months (95% confidence interval, 6.7-11.2), in agreement with other series. In this editorial, the context and implications of these results are discussed, with a particular focus on the possible need and design of randomized phase III trials.

The impact of repeated surgery and adjuvant therapy on survival for patients with recurrent glioblastoma

OBJECTIVE

Treatment of glioblastoma recurrence can have a palliative aim, after considering risks and potential benefits. The aim of this study is to verify the impact of surgery and of palliative adjuvant treatments on survival after recurrence.

METHODS

From January 2002 to June 2008, we treated 76 consecutive patients with recurrent glioblastoma. Treatment was: 1-surgery alone--17 patients; 2-adjuvant-therapy alone--24 patients; 3-surgery and adjuvant therapy--16 patients; no treatment--19 patients. The impact on median overall-survival (OS-time between recurrence and death/last follow-up) of age, Karnofsky performance scale (KPS), resection extent and adjuvant treatment scheme (Temozolomide alone vs low-dose fractionated radiotherapy vs others) was determined. Survival curves were obtained through the Kaplan-Meier method. Cox proportional-hazards was used for multivariate analyses. Significance was set at p<0.05.

RESULTS

Median OS was 7 months. At univariate analysis, patients with a KPS≥70 had a longer OS (9 months vs 5 months--p<0.0001). OS was 6 months for patients treated with surgery alone, 5 months for patients that received no treatment, 8 months for patients treated with chemotherapy alone, 14 months for patients treated with surgery and adjuvant therapy--p=0.01. Patients with a KPS<70 were significantly at risk for death - HR 2.8 - p=0.001. Subgroup analysis showed no significant differences between patients receiving gross total or partial tumor resection and among patients receiving different adjuvant therapy schemes. Major surgical morbidity at tumor recurrence occurred in 16 out of 33 patients (48%).

CONCLUSION

It is fundamental, before deciding to operate patients for recurrence, to carefully consider the impact of surgical morbidity on outcome.

NovoTTF-100A versus physician's choice chemotherapy in recurrent glioblastoma: a randomised phase III trial of a novel treatment modality

PURPOSE

NovoTTF-100A is a portable device delivering low-intensity, intermediate frequency electric fields via non-invasive, transducer arrays. Tumour Treatment Fields (TTF), a completely new therapeutic modality in cancer treatment, physically interfere with cell division.

METHODS

Phase III trial of chemotherapy-free treatment of NovoTTF (20-24h/day) versus active chemotherapy in the treatment of patients with recurrent glioblastoma. Primary end-point was improvement of overall survival.

RESULTS

Patients (median age 54 years (range 23-80), Karnofsky performance status 80% (range 50-100) were randomised to TTF alone (n=120) or active chemotherapy control (n=117). Number of prior treatments was two (range 1-6). Median survival was 6.6 versus 6.0 months (hazard ratio 0.86 [95% CI 0.66-1.12]; p=0.27), 1-year survival rate was 20% and 20%, progression-free survival rate at 6 months was 21.4% and 15.1% (p=0.13), respectively in TTF and active control patients. Responses were more common in the TTF arm (14% versus 9.6%, p=0.19). The TTF-related adverse events were mild (14%) to moderate (2%) skin rash beneath the transducer arrays. Severe adverse events occurred in 6% and 16% (p=0.022) of patients treated with TTF and chemotherapy, respectively. Quality of life analyses favoured TTF therapy in most domains.

CONCLUSIONS

This is the first controlled trial evaluating an entirely novel cancer treatment modality delivering electric fields rather than chemotherapy. No improvement in overall survival was demonstrated, however efficacy and activity with this chemotherapy-free treatment device appears comparable to chemotherapy regimens that are commonly used for recurrent glioblastoma. Toxicity and quality of life clearly favoured TTF.

State of the art and perspectives in the treatment of glioblastoma

Glioblastoma is the most common malignant primary brain tumor. Cures are rare and median survival varies from several to 22 months. Standard treatment for good performance patients consists of maximal safe surgical resection followed by radiotherapy with concurrent temozolomide (TMZ) chemotherapy and six cycles of postradiotherapy TMZ. At recurrence, treatment options include repeat surgery (with or without Gliadel wafer placement), reirradiation or systemic therapy. Most patients with good performance status are treated with cytotoxic chemotherapy or targeted biologic therapy following or in lieu of repeat surgery. Cytotoxic chemotherapy options include nitrosoureas, rechallenge with TMZ, platins, phophoramides and topoisomerase inhibitors, although efficacy is limited. Despite the intense effort of developing biologic agents that target angiogenesis and growth and proliferative pathways, bevacizumab is the only agent that has shown efficacy in clinical trials. It was awarded accelerated approval in the USA after demonstrating an impressive radiographic response in two open-label, prospective Phase II studies. Two randomized, Phase III trials of upfront bevacizumab have completed and may demonstrate survival benefit; however, results are pending at this time. Given the limited treatment options at tumor recurrence, consideration for enrollment on a clinical trial is encouraged.

Doxorubicin-loaded silk films: drug-silk interactions and in vivo performance in human orthotopic breast cancer

Breast cancer is the most common of all malignant diseases in women. Systemic chemotherapy provides low clinical benefit for locoregional control of the disease, while localised chemotherapy may provide a therapeutic advantage. In this study, doxorubicin-loaded silk films were directly applied to tumours. Affinity binding studies demonstrated that the adsorption of doxorubicin onto silk was partially dependent on crystallinity. By manipulating silk crystallinity, or β-sheet content, the doxorubicin release rate could be controlled ranging from immediate release to prolonged release over >4 weeks. The therapeutic impact of doxorubicin-loaded silk films on primary tumour growth and metastasis was assessed in mice using a humanised orthotopic breast cancer model (adenocarcinoma). Both soluble and stabilised silk films loaded with doxorubicin had a significantly greater primary tumour response than the equivalent dose of doxorubicin administered intravenously in the absence of the silk film carrier. In addition to reducing primary tumour growth, stabilised silk films loaded with doxorubicin also reduced metastatic spread and autopsy indicated that these films were not associated with any local or systemic toxicities. Collectively, these results suggest that the future use of this approach for localised chemotherapy is promising.

Management of malignant gliomas and primary CNS lymphoma: standard of care and future directions

PURPOSE OF REVIEW

This article review the current standard of care of astrocytic gliomas and primary CNS lymphoma and discusses promising new therapeutic targets.

RECENT FINDINGS

Standard treatment modalities for primary malignant brain tumors include resection, radiation, local or systemic chemotherapy, and, most recently, antiangiogenic agents. However, these tumors often have a rapid course, and patients usually die within a few years of diagnosis. Improved surgical techniques and radiation and chemotherapy can prolong survival while maintaining quality of life, but these therapies remain inadequate.

SUMMARY

The care of patients with malignant brain tumors is challenging. A better understanding of the pathogenesis of primary malignant brain tumors and the elucidation of aberrant molecular pathways are leading to novel treatment strategies and the ability to identify patients who may benefit from specific treatments.

Individual patient-specific immunity against high-grade glioma after vaccination with autologous tumor derived peptides bound to the 96 KD chaperone protein

PURPOSE

Cancer immunotherapy offers hope of a highly specific nontoxic adjuvant treatment. Heat shock protein peptide complexes (HSPPCs) found in cancer cells carry tumor-specific antigenic proteins and can facilitate adaptive and innate immune responses. Here we show that peptides bound to a 96 kD chaperone protein (HSP-96) from brain tissue containing glioblastoma multiforme (GBM) can be used to safely immunize patients with recurrent GBM.

EXPERIMENTAL DESIGN

Multimodality immunomonitoring was completed on 12 patients with recurrent GBM before and after immunization with an autologous HSPPC vaccine derived from surgically resected tumor. Clinical endpoints included safety assessments and overall survival.

RESULTS

No adverse events attributable to the vaccine were found. Testing of peripheral blood leukocytes before and after vaccination revealed a significant peripheral immune response specific for the peptides bound to HSP-96, in 11 of the 12 patients treated. Brain biopsies of immune responders after vaccination revealed focal CD4, CD8, and CD56 IFNγ positive cell infiltrates, consistent with tumor site specific immune responses. Immune responders had a median survival of 47 weeks after surgery and vaccination, compared with 16 weeks for the single nonresponder.

CONCLUSIONS

These data provide the first evidence in humans of individual patient-specific immune responses against autologous tumor derived peptides bound to HSP-96.

Safety and efficacy of Gliadel wafers for newly diagnosed and recurrent glioblastoma

BACKGROUND

Combining Gliadel wafers and radiochemotherapy with TMZ may carry the risk of increased adverse events (AE). We analyzed the efficacy and safety in patients with glioblastoma who underwent multimodal treatment with implantation of Gliadel wafers.

METHODS

One hundred sixty-five consecutive patients with newly diagnosed (77 patients) or recurrent (88 patients) glioblastoma were studied. Forty-seven patients underwent surgery + Gliadel. The impact of age (≥65 vs. <65), resection extent (gross total vs. partial), use of Gliadel and adjuvant treatment (TMZ vs. other schemes/no adjuvant therapy) on overall survival (OS, for patients with newly diagnosed glioblastoma) and on recurrence-survival (for patients with recurrent glioblastoma) was analyzed with Cox regression. The impact of age, history (newly diagnosed vs. recurrent glioblastoma), number of Gliadel wafers implanted (0 vs. <8 vs. 8), resection extent (gross-total vs. partial) and adjuvant treatment (TMZ vs. other schemes/no adjuvant therapy) on the occurrence of AE and on the occurrence of implantation site-related AE (ISAE) was analyzed with the logistic regression model. Significance was set at p < 0.05.

RESULTS

Multivariate analysis showed the only factor associated with longer survival, both for newly diagnosed and for recurrent GBM, was resection extent. Both patients with a higher number of wafers implanted and patients with recurrent tumors were significantly at risk for AE and ISAE. Patients with eight Gliadel wafers implanted had a 3-fold increased risk of AE and a 5.6-fold increased risk of ISAE, and patients with recurrent tumor had a 2.8-fold increased risk of AE and a 9.3-fold increased risk of ISAE.

CONCLUSIONS

Adding Gliadel to standard treatment did not significantly improve the outcome. The toxicity after Gliadel use was significantly higher, both for patients with newly diagnosed and patients with recurrent glioblastoma.

Intracranial drug delivery for subarachnoid hemorrhage

Tice and colleagues pioneered site-specific, sustained-release drug delivery to the brain almost 30 years ago. Currently there is one drug approved for use in this manner. Clinical trials in subarachnoid hemorrhage have led to approval of nimodipine for oral and intravenous use, but other drugs, such as clazosentan, hydroxymethylglutaryl CoA reductase inhibitors (statins) and magnesium, have not shown consistent clinical efficacy. We propose that intracranial delivery of drugs such as nimodipine, formulated in sustained-release preparations, are good candidates for improving outcome after subarachnoid hemorrhage because they can be administered to patients that are already undergoing surgery and who have a self-limited condition from which full recovery is possible.

Temozolomide and other potential agents for the treatment of glioblastoma multiforme

This article provides historical and recent perspectives related to the use of temozolomide for the treatment of glioblastoma multiforme. Temozolomide has quickly become part of the standard of care for the modern treatment of stage IV glioblastoma multiforme since its approval in 2005. Yet despite its improvements from previous therapies, median survival remains approximately 15 months, with a 2-year survival rate of 8% to 26%. The mechanism of action of this chemotherapeutic agent, conferred advantages and limitations, treatment resistance and rescue, and potential targets of future research are discussed.

Epidemiology of glial and non-glial brain tumours in Europe

To the central nervous system (CNS) belong a heterogeneous group of glial and non glial rare cancers. The aim of the present study was to estimate the burden (incidence, prevalence, survival and proportion of cured) for the principal CNS cancers in Europe (EU27) and in European regions using population-based data from cancer registries participating in the RARECARE project. We analysed 44,947 rare CNS cancers diagnosed from 1995 to 2002 (with follow up at 31st December 2003): 86.0% astrocytic (24% low grade, 63% high grade and 13% glioma NOS), 6.4% oligodendroglial (74% low grade), 3.6% ependymal (85% low grade), 4.1% Embryonal tumours and 0.1% choroid plexus carcinoma. Incidence rates vary widely across European regions especially for astrocytic tumours ranging from 3/100,000 in Eastern Europe to 5/100,000 in United Kingdom and Ireland. Overall, about 27,700 new rare CNS cancers were estimated every year in EU27, for an annual incidence rate of 4.8 per 100,000 for astrocytic, 0.4 for oligodendroglial, 0.2 for ependymal and embryonal tumours and less than 0.1 for choroid plexus carcinoma. More than 154,000 persons with rare CNS were estimated alive (prevalent cases) in the EU at the beginning of 2008. Five-year relative survival was 14.5% for astrocytic tumours (42.6% for low grade, 4.9% for high grade and 17.5% for glioma NOS), 54.5% for oligodendroglial (64.9% high grade and 29.6% low grade), 74.2% for ependymal (80.4% low grade and 36.6% high grade), 62.8% for choroid plexus carcinomas and 56.8% for embryonal tumours. Survival rates for astrocytic tumours were relatively higher in Northern and Central Europe than in Eastern Europe and in UK and Ireland. The different availability of diagnostic imaging techniques and/or radiation therapy equipment across Europe may contribute to explain the reported survival differences. The estimated proportion of cured patients was 7.9% for the 'glial' group to which belong astrocytic tumours. Overall results are strongly influenced by astrocytic tumours that are the most common type. This is the first study to delineate the rare CNS cancer burden in Europe by age, sex and European region.

11C-Methionine Positron Emission Tomographic Imaging of Biologic Activity of a Recurrent Glioblastoma Treated with Stereotaxy-Guided Laser-Induced Interstitial Thermotherapy

In patients with recurrent glioblastoma multiforme (GBM), local minimally invasive treatment modalities have gained increasing interest recently because they are associated with fewer side effects than open surgery. For example, local tumor coagulation by laser-induced interstitial thermotherapy (LITT) is such a minimally invasive technique. We monitored the metabolic effects of stereotaxy-guided LITT in a patient with a recurrent GBM using amino acid positron emission tomography (PET). Serial 11C-methyl-L-methionine positron emission tomography (MET-PET) and contrast-enhanced computed tomography (CT) were performed using a hybrid PET/CT system in a patient with recurrent GBM before and after LITT. To monitor the biologic activity of the effects of stereotaxy-guided LITT, a threshold-based volume of interest analysis of the metabolically active tumor volume (MET uptake index of ≥ 1.3) was performed. A continuous decline in metabolically active tumor volume after LITT could be observed. MET-PET seems to be useful for monitoring the short-term therapeutic effects of LITT, especially when patients have been pretreated with a multistep therapeutic regimen. MET-PET seems to be an appropriate tool to monitor and guide experimental LITT regimens and should be studied in a larger patient group to confirm its clinical value.

Drug delivery strategies for the treatment of malignant gliomas

As primary brain tumors, malignant gliomas are known to be one of the most insidious types of brain cancer afflicting the humans. The current standard strategy for the treatment of malignant gliomas includes the surgical resection of the tumor when possible, followed by a combination of radiotherapy and/or a certain chemotherapeutic protocol. However, due to the short mean survival, frequent recurrences, and poor prognosis associated with the tumors, new therapeutic strategies are investigated consecutively. These novel drug delivery approaches can be subdivided as systemic and local drug administration. This review focuses on localized drug delivery strategies for the treatment of malignant gliomas, including the injections, infusions, trans-nasal delivery systems, convection enhanced delivery (CED) systems, and various types of polymeric implants. Furthermore, systemic strategies to increase the drug penetration into the brain, such as temporary disruption of the blood brain barrier (BBB), chemical modification of the available therapeutic substances, and utilization of endogenous transport systems will be briefly discussed.

Nanotechnology applications for glioblastoma

Glioblastoma remains one of the most difficult cancers to treat and represents the most common primary malignancy of the brain. Although conventional treatments have found modest success in reducing the initial tumor burden, infiltrating cancer cells beyond the main mass are responsible for tumor recurrence and ultimate patient demise. Targeting residual infiltrating cancer cells requires the development of new treatment strategies. The emerging field of cancer nanotechnology holds promise in the use of multifunctional nanoparticles for imaging and targeted therapy of glioblastoma. This article examines the current state of nanotechnology in the treatment of glioblastoma and directions of further study.

Clinical trials of small molecule inhibitors in high-grade glioma

High-grade gliomas are rapidly progressing and generally fatal neoplasms of the brain. Chemotherapy has continued to provide only limited benefit for patients harboring these tumors. The recurrence of common mutations, combined with the similarities of many of the acquired capabilities and characteristics of solid tumors, suggest many common therapeutic targets. During the past few decades, an increased understanding of many of the cellular regulatory mechanisms associated with carcinogenesis has provided an opportunity for the development of pathway-specific small molecule targeted inhibitors (SMIs). This article reviews the use of SMIs in the treatment of high-grade glioma.

Novel delivery strategies for glioblastoma

Brain tumors--particularly glioblastoma multiforme--pose an important public health problem in the United States. Despite surgical and medical advances, the prognosis for patients with malignant gliomas remains grim: current therapy is insufficient with nearly universal recurrence. A major reason for this failure is the difficulty of delivering therapeutic agents to the brain: better delivery approaches are needed to improve treatment. In this article, we summarize recent progress in drug delivery to the brain, with an emphasis on convection-enhanced delivery of nanocarriers. We examine the potential of new delivery methods to permit novel drug- and gene-based therapies that target brain cancer stem cells and discuss the use of nanomaterials for imaging of tumors and drug delivery.

Glioblastoma cancer stem-like cells: implications for pathogenesis and treatment

Glioblastoma remains one of the deadliest forms of cancer. Infiltrating cancer cells in the surrounding brain prevent complete resection, and tumor cell resistance to chemoradiation results in the poor prognosis of the glioblastoma (GBM) patient. Much research has been devoted over the years to the pathogenesis and treatment of GBM. The tumor stem cell hypothesis, which was initially described in hematopoietic cell malignancies, may explain the resistance of these tumors to conventional therapies. In this model, a certain subset of tumor cells, with characteristics similar to normal stem cells, is capable of producing the variety of cell types, which constitute the bulk of a tumor. As these tumor cells have properties distinct from those constituting the bulk of the tumor, a different approach may be required to eradicate these residual cells within the brain. Here we outline the history behind the theory of GBM cancer stem-like cells, as they are now referred to. We will also discuss the implications of their existence on commonly held beliefs about GBM pathogenesis and how they might influence future treatment strategies.

Polymeric nanoparticles for drug delivery to the central nervous system

The central nervous system (CNS) poses a unique challenge for drug delivery. The blood-brain barrier significantly hinders the passage of systemically delivered therapeutics and the brain extracellular matrix limits the distribution and longevity of locally delivered agents. Polymeric nanoparticles represent a promising solution to these problems. Over the past 40years, substantial research efforts have demonstrated that polymeric nanoparticles can be engineered for effective systemic and local delivery of therapeutics to the CNS. Moreover, many of the polymers used in nanoparticle fabrication are both biodegradable and biocompatible, thereby increasing the clinical utility of this strategy. Here, we review the major advances in the development of polymeric nanoparticles for drug delivery to the CNS.

Glioblastoma multiforme: overview of current treatment and future perspectives

Glioblastoma multiforme is the most common primary malignant tumor of the central nervous system. Despite new insights into glioblastoma pathophysiology, the prognosis for patients diagnosed with this highly aggressive tumor remains bleak. Current treatment regimens combine surgical resection and chemoradiotherapy, providing an increase in median overall survival from 12.1 to 14.6 months. Ongoing preclinical and clinical studies evaluating the efficacy of novel therapies provide hope for increasing survival benefit. This article reviews the advancements in glioblastoma treatment in newly diagnosed and recurrent glioblastoma, including novel therapies such as antiangiogenic agents, mammalian target of rapamycin inhibitors, poly(ADP-ribose) polymerase-1 inhibitors, and immunotherapies.

Forty-year journey of angiogenesis translational research

Forty years ago, Judah Folkman predicted that tumor growth is dependent on angiogenesis and that inhibiting this process might be a new strategy for cancer therapy. This hypothesis formed the foundation of a new field of research that represents an excellent example of how a groundbreaking scientific discovery can be translated to yield benefits for patients. Today, antiangiogenic drugs are used to treat human cancers and retinal vascular diseases. Here, we guide readers through 40 years of angiogenesis research and discuss challenges of antiangiogenic therapy.

Induced Smoothing for the Semiparametric Accelerated Hazards Model

Compared to the proportional hazards model and accelerated failure time model, the accelerated hazards model has a unique property in its application, in that it can allow gradual effects of the treatment. However, its application is still very limited, partly due to the complexity of existing semiparametric estimation methods. We propose a new semiparametric estimation method based on the induced smoothing and rank type estimates. The parameter estimates and their variances can be easily obtained from the smoothed estimating equation; thus it is easy to use in practice. Our numerical study shows that the new method is more efficient than the existing methods with respect to its variance estimation and coverage probability. The proposed method is employed to reanalyze a data set from a brain tumor treatment study.

Infections in neuro-oncology

Infections represent a serious and frequent complication in neuro-oncology patients. Decreased immune defences, along with poor nutritional status are the main predisposition factors. The combined therapeutic strategies of chemotherapy and radiotherapy may favour bone marrow depression and further increase the risk of developing opportunistic infections in brain tumour patients. The spectrum of infections in neuro-oncology patients is large and includes opportunistic infections by bacteria, viruses, fungi and parasites. Importantly, a high index of suspicion for opportunistic infections in general should be maintained, especially in glioma patients receiving dose-dense schedules of temozolomide. After neurosurgical procedures, infections most commonly present as meningitis, subdural empyema, or cerebral abscess. Infections represent a frequent and possibly serious complication in general immunocompromised oncology population. It should be underlined that infections are not limited to immunocompromised patients, being also present at the early disease stages, especially due to therapeutic strategies (chemo and radiotherapy, surgical procedures). Therefore this issue deserves more attention in neuroncology setting.

Pilot trial of endoscopic ultrasound-guided interstitial chemoradiation of UICC-T4 pancreatic cancer

BACKGROUND AND AIMS

Both interstitial brachytherapy and interstitial chemotherapy are effective in improving local control in patients with local UICC-T4 pancreatic cancer. In this study, we report the results of endoscopic ultrasound (EUS)-guided interstitial chemoradiation (EUS-ICR) in patients with advanced pancreatic cancer, with respect to tumor response, clinical response, safety, and complications.

PATIENTS AND METHODS

A total of 8 patients (3 men, 5 women; median age of 69) with T4 pancreatic adenocarcinoma were the subjects of this study. A mean of 18 radioactive seeds and 36 intratumoral implants for sustained delivery of 5-fluorouracil in each patient were implanted into the tumors using EUS-guided needle puncture. The mean total implanted radioactive activity was 13.68 mCi, the mean total dose of intratumoral 5-fluorouracil was 3.6 g, and the mean volume of implants was 28 cm(3). The conditions of the patients were followed-up by examination and imaging tests every two months. Clinical endpoints included the Karnofsky performance status, pain response, tumor response (assessed by computed tomography and/or EUS), and survival.

RESULTS

During a median follow-up period of 8.3 months, the objective tumor response was classified as "partial" in 1 of 8 patients (with a median duration of partial response of 3 months), "minimal" in 2 patients, and indicative of "stable disease", in 3 of 8 patients. Clinical benefit was shown in 4 of 8 patients, which was mostly due to pain reduction, and lasted for 3.5 months. No local complications or hematologic toxicity occurred.

CONCLUSIONS

EUS-ICR had a moderate local anti-tumor effect, showed some clinical benefits in 4 of the 8 patients, and was well tolerated by all the patients in this study.

Evolution of care for patients with relapsed glioblastoma

Glioblastoma is the most common and aggressive form of brain tumor in adults and has a poor prognosis and a high recurrence rate despite optimal care. The management of patients with relapsed glioblastoma is challenging, with no widely agreed standard of care. Different chemotherapy and radiotherapy combination treatment strategies provide only modest benefits. Recently, several novel agents, including bevacizumab and XL-184, have demonstrated promising results in Phase II trials with their further evaluation ongoing in Phase III randomized trials. Interpreting the data from such trials is a key challenge in glioblastoma, highlighting the need for relevant and standardized patient assessment techniques. Data from ongoing and planned trials should help to define optimal treatment strategies for this disease.

The role of BCNU polymer wafers (Gliadel) in the treatment of malignant glioma

The 1,3-bis(2-chloroethyl)-1-nitrosourea (BCNU; carmustine) polymer wafer (Gliadel) was developed for use in malignant glioma to deliver higher doses of chemotherapy directly to tumor tissue while bypassing systemic side effects. Phase III clinical trials for patients with newly diagnosed malignant gliomas demonstrated a small, but statistically significant, improvement in survival. However, the rate of complications, including an increase in cerebrospinal fluid leaks and intracranial hypertension, has limited their use. This article reviews the current data for use of BCNU wafers in malignant gliomas.

Delayed onset of paresis in rats with experimental intramedullary spinal cord gliosarcoma following intratumoral administration of the paclitaxel delivery system OncoGel

OBJECT

Treatment options for anaplastic or malignant intramedullary spinal cord tumors (IMSCTs) remain limited. Paclitaxel has potent cytotoxicity against experimental intracranial gliomas and could be beneficial in the treatment of IMSCTs, but poor CNS penetration and significant toxicity limit its use. Such limitations could be overcome with local intratumoral delivery. Paclitaxel has been previously incorporated into a biodegradable gel depot delivery system (OncoGel) and in this study the authors evaluated the safety of intramedullary injections of OncoGel in rats and its efficacy against an intramedullary rat gliosarcoma.

METHODS

Safety of intramedullary OncoGel was tested in 12 Fischer-344 rats using OncoGel concentrations of 1.5 and 6.0 mg/ml (5 μl); median survival and functional motor scores (Basso-Beattie-Bresnahan [BBB] scale) were compared with those obtained with placebo (ReGel) and medium-only injections. Efficacy of OncoGel was tested in 61 Fischer-344 rats implanted with an intramedullary injection of 9L gliosarcoma containing 100,000 cells in 5 μl of medium, and randomized to receive OncoGel administered on the same day (in 32 rats) or 5 days after tumor implantation (in 29 rats) using either 1.5 mg/ml or 3.0 mg/ml doses of paclitaxel. Median survival and BBB scores were compared with those of ReGel-treated and tumor-only rats. Animals were killed after the onset of deficits for histopathological analysis.

RESULTS

OncoGel was safe for intramedullary injection in rats in doses up to 5 μl of 3.0 mg/ml of paclitaxel; a dose of 5 μl of 6.0 mg/ml caused rapid deterioration in BBB scores. OncoGel at concentrations of 1.5 mg/ml and 3.0 mg/ml paclitaxel given on both Day 0 and Day 5 prolonged median survival and preserved BBB scores compared with controls. OncoGel 1.5 mg/ml produced 62.5% long-term survivors when delivered on Day 0. A comparison between the 1.5 mg/ml and the 3.0 mg/ml doses showed higher median survival with the 1.5 mg/ml dose on Day 0, and no differences in median survival or BBB scores after treatment on Day 5.

CONCLUSIONS

OncoGel is safe for intramedullary injection in rats in doses up to 5 μl of 3.0 mg/ml, prolongs median survival, and increases functional motor scores in rats challenged with an intramedullary gliosarcoma at the doses tested. This study suggests that locally delivered chemotherapeutic agents could be of temporary benefit in the treatment of malignant IMSCTs under experimental settings.

Temporal changes in magnetic resonance imaging characteristics of Gliadel wafers and of the adjacent brain parenchyma

Carmustine is used in the treatment of glioblastomas as locally applied chemotherapy in the form of biodegradable wafers, which are lined on the walls of the resection cavity at the end of the resection, to increase local concentrations and decrease systemic toxicity. A total of 44 patients with glioblastoma with gross macroscopic tumor removal were included. MRIs were performed at various times postoperatively (within 24 hours, 1 week, 1 month, 2 months, 3 months, 6 months, 9 months, and 1 year). MR protocols included a T2-, diffusion-weighted, and T1-weighted sequences with and without intravenous administration of gadolinium. On T1, the wafers change from their initial hypointense to an isointense appearance after a period during which they appear to be hypointense, with a hyperintense rim most prominent less than 1 month postoperatively. On T2 they change from a hypointense to an isointense appearance. Restricted diffusivity reshaping the silhouette of the wafer's surface at the rim of the resection cavity can be found as early as day 1 postoperatively; however, 1 month after implantation, they all show areas of restricted diffusion, which may remain up to 1 year. Contrast enhancement at the rim of the resection cavity can already be found at day 1 postoperatively, with a peak shortly after 1 month after surgery. These changes can easily be mistaken for an abscess and hamper the early differentiation between residual tumor tissue and normal postoperative changes. However, early changes in either appearance do not predict overall survival or the progression free interval.

Prognostic factors and survival in a prospective cohort of patients with high-grade glioma treated with carmustine wafers or temozolomide on an intention-to-treat basis

BACKGROUND

Patients with high-grade glioma can be treated with carmustine wafers or following the Stupp protocol. As far as we are aware, no scientific evidence has been published comparing the two treatments. The primary objective of this study was to analyse the survival of groups of patients with each of these treatment modalities. The secondary objective was to assess the influence of the usual prognostic factors on the patients in our hospital.

METHODS

A prospective cohort of 110 patients with single, supratentorial high-grade glioma treated by craniotomy and tumour resection was retrospectively studied. Half of the patients had carmustine wafers placed during this operation while the others (55) did not, the latter group receiving first-line systemic chemotherapy on an intention-to-treat basis.

FINDINGS

Patients treated with carmustine wafers had a median survival of 13.414 months compared with 11.047 in the group without implants (p = 0.856). For the overall cohort of patients, the following factors were found to influence survival: age (p < 0.0001), postoperative KPS score (p = 0.001), histological grade (p = 0.004), RPA class (p = 0.001), extent of resection (p = 0.002) and salvage surgery (p = 0.028).

CONCLUSIONS

In this prospective cohort of patients, analysed on the basis of intention-to-treat at the time of the first surgery, no statistically significant differences in survival were found between the two treatment modalities (carmustine wafers vs. first-line systemic chemotherapy). On the other hand, age, preoperative KPS, histological grade, and RPA class were confirmed to be prognostic factors in this cohort. Finally, the extent of resection was also found to influence survival.

Establishing the standard of care for patients with newly diagnosed and recurrent glioblastoma

The current standard of care for patients with newly diagnosed glioblastoma includes maximal safe tumor resection followed by concurrent external-beam radiation with daily low-dose temozolomide followed by 6 to 12 months of adjuvant temozolomide, typically by using a cycle of 5 consecutive days out of 28. Efforts to improve on these results from the European Organisation for Research and Treatment of Cancer (EORTC)/National Cancer Institute of Canada (NCIC) trial using either dose-dense chemotherapy strategies or combinations with signal transduction modulators have, to date, been unsuccessful. Two large international randomized trials examining the efficacy of adding bevacizumab, an antiangiogenic agent, to the standard treatment have been completed, with expectations of results within in the next 2 years. For recurrent glioblastoma, there are no firmly established standards of care. Although intracavitary insertion of carmustine-impregnated polymers has been approved by the U.S. Food and Drug Administration (FDA), this strategy is not widely used. Bevacizumab has been FDA approved for recurrent glioblastoma, but no randomized trial has clearly demonstrated a survival benefit. Alternative dosing schedules of temozolomide (i.e., metronomic) has modest activity even in patients with prior temozolomide exposure. Clinical trials testing small-molecule signal transduction modulators have been disappointing, although most report a small response rate, suggesting that molecularly definable tumor subpopulations may help guide treatment decisions. Successful implementation of marker-based treatment would lead to personalized care and the creation of individualized standards of care.