Add-on bevacizumab can prevent early clinical deterioration and prolong survival in newly diagnosed partially resected glioblastoma patients with a poor performance status

Is add-on Bevacizumab therapy to Temozolomide and radiotherapy associated with clinical utility for newly diagnosed Glioblastoma? A systematic review and meta-analysis

Bevacizumab, temozolomide (TMZ), and radiotherapy are three therapeutic methods, but the combination of them as a new approach for the treatment of newly diagnosed high-grade gliomas (HGGs) is still under investigation. Therefore, this study aims to evaluate the safety, efficacy, and clinical utility of this treatment approach for patients with glioblastoma (GBM). PubMed/Medline, Scopus, Embase, and Web of Science were systematically reviewed from inception to 24 August 2023. Relevant studies evaluating the therapeutic effect of adding Bevacizumab to TMZ-based chemotherapy and radiation therapy were enrolled. All statistical analysis was performed using the "meta" package of R. A total of 21 studies were included in this study. Our meta-analysis found that adding bevacizumab to standard therapy improved progression-free survival (PFS) in patients with newly diagnosed GBM. The pooled 6-month PFS rate was significantly higher with bevacizumab (79% vs. 56%, odds ratio 3.17). Overall survival (OS) showed modest improvements, with 2-year OS rates of 39% vs. 20% favoring bevacizumab. Radiological response rates varied, with a pooled overall response rate of 44% for bevacizumab-treated patients. The complete response rate was 16%, partial response 32%, and progressive disease 25%. Adverse events occurred in 62% of bevacizumab-treated patients. Common complications included fatigue, thrombocytopenia, and thromboembolic events. When added to standard therapy, bevacizumab demonstrates modest improvements in PFS and OS for newly diagnosedGBM. While it shows promise in short-term outcomes and radiological responses, long-term survival benefits remain limited. The risk of adverse events, particularly CNS hemorrhage, necessitates careful patient selection. These findings suggest that bevacizumab may have a role in treating high-grade gliomas, but its use should be individualized based on patient characteristics and risk-benefit assessment.

Timing of bevacizumab administration after biopsy for unresectable newly diagnosed glioblastoma

Background

Recent studies have revealed that bevacizumab (BEV) can improve the survival of patients with newly diagnosed unresectable glioblastoma (GBM) with poor performance status. For patients who develop early clinical deterioration, early initiation of BEV would be beneficial. However, the safety and feasibility of early initiation of BEV remain to be determined because of the lack of studies addressing adverse events associated with BEV initiation <28 days after surgery. The aim of this study was to analyze the risks and benefits of early BEV administration after biopsy in patients with newly diagnosed GBM.

Methods

Thirty-one consecutive patients with newly diagnosed GBM who underwent biopsy followed by BEV administration were investigated. The relationships between the timing of BEV administration and treatment response, survival outcome, and adverse events were analyzed.

Results

Response rates based on the RANO criteria and overall survival times were similar between the early and standard BEV groups. No wound dehiscence was observed in the early BEV group, and only one case was observed in the standard BEV group. Patients in the early BEV group were more likely to have undergone biopsy with a smaller skin incision than those in the standard BEV group. Equivalent treatment effects of BEV were achieved in patients who developed early clinical deterioration and those without clinical deterioration.

Conclusion

Early BEV administration is effective in controlling early clinical deterioration and does not increase the risk of wound-healing complications. Further studies with larger numbers of patients are needed to validate our results.

Changes in the Relapse Pattern and Prognosis of Glioblastoma After Approval of First-Line Bevacizumab: A Single-Center Retrospective Study

BACKGROUND

Controversies exist regarding the aggressive recurrence of glioblastoma after bevacizumab treatment. We analyzed the clinical impact of bevacizumab approval in Japan by evaluating the clinical course and relapse pattern in patients with glioblastoma.

METHODS

We included 100 patients with IDH-wildtype glioblastoma from September 2006 to February 2018 in our institution. The patients were classified into pre-bevacizumab (n = 51) and post-bevacizumab (n = 49) groups. Overall, progression-free, deterioration-free, and post-progression survivals were compared. We analyzed the relapse pattern of 72 patients, whose radiographic progressions were evaluated.

RESULTS

Significant improvement in progression-free (pre-bevacizumab, 7.5 months; post-bevacizumab, 9.9 months; P = 0.0153) and deterioration-free (pre-bevacizumab, 8.5 months; post-bevacizumab, 13.8 months; P = 0.0046) survivals were seen. These survival prolongations were strongly correlated (r: 0.91, P < 0.0001). The non-enhancing tumor pattern was novel in the post-bevacizumab era (5/33). The presence of a non-enhancing tumor did not indicate poor post-progression survival (hazard ratio: 0.82 [0.26-2.62], P = 0.7377). The rate of early focal recurrence was significantly lower (P = 0.0155) in the post-bevacizumab (4/33) than in the pre-bevacizumab (18/39) era. There was a significant decrease in early focal recurrence after approval of bevacizumab in patients with unresectable tumors (P = 0.0110). The treatment era was significantly correlated with a decreased rate of early focal recurrence (P = 0.0021, univariate analysis; P = 0.0144, multivariate analysis).

CONCLUSIONS

Approval of first-line bevacizumab in Japan for unresectable tumors may prevent early progression and clinical deterioration of glioblastoma without worsening the clinical course following relapse.

Volumetric study reveals the relationship between outcome and early radiographic response during bevacizumab-containing chemoradiotherapy for unresectable glioblastoma

PURPOSE

Although we have shown the clinical benefit of bevacizumab (BEV) in the treatment of unresectable newly diagnosed glioblastomas (nd-GBM), the relationship between early radiographic response and survival outcome remains unclear. We performed a volumetric study of early radiographic responses in nd-GBM treated with BEV.

METHODS

Twenty-two patients with unresectable nd-GBM treated with BEV during concurrent temozolomide radiotherapy were analyzed. An experienced neuroradiologist interpreted early responses on fluid-attenuated inversion recovery (FLAIR) and gadolinium-enhanced T1-weighted images (GdT1WI). Volumetric changes were evaluated using diffusion-weighted imaging (DWI) and GdT1WI according to the Response Assessment in Neuro-Oncology (RANO) criteria. The results were categorized into improved (complete response [CR] or partial response [PR]) or non-improved (stable disease [SD] or progressive disease [PD]) groups; outcomes were compared using Kaplan-Meier analysis.

RESULTS

The volumetric GdT1WI improvement was a significant predictive factor for overall survival (OS) prolongation (p = 0.0093, median OS: 24.7 vs. 13.6 months); however, FLAIR and DWI images were not predictive. The threshold for the neuroradiologist's interpretation of improvement in GdT1WI was nearly 20% of volume reduction, which was lesser than 50%, the definition of PR applied in the RANO criteria. However, even less stringent neuroradiologist interpretation could successfully predict OS prolongation (improved vs. non-improved: p = 0.0067, median OS: 17.6 vs. 8.3 months). Significant impact of OS on the early response in volumetric GdT1WI was observed within the cut-off range of 20-50% (20%, p = 0.0315; 30%, p = 0.087; 40%, p = 0.0456).

CONCLUSIONS

Early response during BEV-containing chemoradiation can be a predictive indicator of patient outcome in unresectable nd-GBM.

Current trend in treatment of glioblastoma in Japan: a national survey using the diagnostic procedure combination database (J-ASPECT study-glioblastoma)

Background

In the treatment for glioblastoma (GBM), treatment modalities, such as bevacizumab (BEV) and carmustine wafers implants have been approved in Japan since 2013. However, it is unclear whether such a trend in treatment complexity can accelerate treatment centralization. The aim of this study was to reveal the current trend in the treatment of GBM in Japan.

Methods

We used diagnostic procedure combination (DPC) database to analyze the data of 1,774 patients from 305 institutions between April 2016 and March 2019. To analyze the situations associated with first-line BEV use during concurrent TMZ (temozolomide)-radiotherapy, we compared TMZ alone and TMZ–BEV groups.

Results

Of the 1,774 patients with GBM, tumor removal by craniotomy was performed in 1,572 (88.6%) patients, and stereotactic biopsy was performed in 156 (8.8%) patients. A total of 1,229 (69.3%) patients underwent radiotherapy, and 1,287 (72.5%) patients underwent chemotherapy. TMZ alone was administered to 878 (68.2%) and TMZ combined with BEV in 381 (29.6%) patients. In the TMZ–BEV group, as compared to the TMZ-alone group, the rate of discharge to home was significantly lower (P = 0.0044), and the rate of stereotactic biopsy was significantly higher (P < 0.0001). No significant difference was observed in the distribution of patients between the TMZ alone and TMZ–BEV groups depending on the scale of institution (P = 0.1240).

Conclusion

First-line BEV administration seems to be selected properly regardless of the institutional scale. This Japan-wide study of GBM treatment revealed that high level and newly introduced treatments have been steadily generalized in Japanese institutions.

Clinical significance of CDKN2A homozygous deletion in combination with methylated MGMT status for IDH-wildtype glioblastoma

OBJECTIVE

Accumulating evidence from recent molecular diagnostic studies has indicated the prognostic significance of various genetic markers for patients with glioblastoma (GBM). To evaluate the impact of such genetic markers on prognosis, we retrospectively analyzed the outcomes of patients with IDH-wildtype GBM in our institution. In addition, to assess the impact of bevacizumab (BEV) treatment, we compared overall survival (OS) between the pre- and post-BEV eras.

METHODS

We analyzed the data of 100 adult patients (over 18 years old) with IDH-wildtype GBM from our database between February 2006 and October 2018. Genetic markers, such as MGMT methylation status, EGFR amplification, CDKN2A homozygous deletion, and clinical factors were analyzed by evaluating the patients' OS.

RESULTS

CDKN2A homozygous deletion showed no significant impact on OS in patients with methylated MGMT status (p = 0.5268), whereas among patients with unmethylated MGMT status, there was a significant difference in OS between patients with and without CDKN2A homozygous deletion (median OS: 14.7 and 16.9 months, respectively, p = 0.0129). This difference was more evident in the pre-BEV era (median OS: 10.1 and 15.6 months, respectively, p = 0.0351) but has become nonsignificant in the post-BEV era (median OS: 16.0 and 16.9 months, respectively, p = 0.1010) due to OS improvement in patients with CDKN2A homozygous deletion. However, these findings could not be validated in The Cancer Genome Atlas cohort.

CONCLUSIONS

MGMT and CDKN2A status subdivided our cohort into three race-specific groups with different prognoses. Our findings indicate that BEV approval in Japan led to OS improvement exclusively for patients with concurrent unmethylated MGMT status and CDKN2A homozygous deletion.

Molecular diagnosis of diffuse glioma using a chip-based digital PCR system to analyze IDH, TERT, and H3 mutations in the cerebrospinal fluid

PURPOSE

Conventional genetic analyzers require surgically obtained tumor tissues to confirm the molecular diagnosis of diffuse glioma. Recent technical breakthroughs have enabled increased utilization of cell-free tumor DNA (ctDNA) in body fluids as a reliable resource for molecular diagnosis in various cancers. Here, we tested the application of a chip-based digital PCR system for the less invasive diagnosis (i.e., liquid biopsy) of diffuse glioma using the cerebrospinal fluid (CSF).

METHODS

CSF samples from 34 patients with diffuse glioma were collected from the surgical field during craniotomy. Preoperative lumbar CSF collection was also performed in 11 patients. Extracted ctDNA was used to analyze diagnostic point mutations in IDH1 R132H, TERT promoter (C228T and C250T), and H3F3A (K27M) on the QuantStudio^® 3D Digital PCR System. These results were compared with their corresponding tumor DNA samples.

RESULTS

We detected either of the diagnostic mutations in tumor DNA samples from 28 of 34 patients. Among them, we achieved precise molecular diagnoses using intracranial CSF in 20 (71%). Univariate analyses revealed that the World Health Organization (WHO) grade (p = 0.0034), radiographic enhancement (p = 0.0006), and Mib1 index (p = 0.01) were significant predictors of precise CSF-based molecular diagnosis. We precisely diagnosed WHO grade III or IV diffuse gliomas using lumbar CSF obtained from 6 (87%) of 7 patients with tumors harboring any mutation.

CONCLUSION

We established a novel, non-invasive molecular diagnostic method using a chip-based digital PCR system targeting ctDNA derived from CSF with high sensitivity and specificity, especially for high-grade gliomas.

Mesenchymal glioblastoma-induced mature de-novo vessel formation of vascular endothelial cells in a microfluidic device

High vascularization is a biological characteristic of glioblastoma (GBM); however, an in-vitro experimental model to verify the mechanism and physiological role of vasculogenesis in GBM is not well-established. Recently, we established a self-organizing vasculogenic model using human umbilical vein endothelial cells (HUVECs) co-cultivated with human lung fibroblasts (hLFs). Here, we exploited this system to establish a realistic model of vasculogenesis in GBM. We developed two polydimethylsiloxane (PDMS) devices, a doughnut-hole dish and a 5-lane microfluidic device to observe the contact-independent effects of glioblastoma cells on HUVECs. We tested five patient-derived and five widely used GBM cell lines. Confocal fluorescence microscopy was used to observe the morphological changes in Red Fluorescent Protein (RFP)-HUVECs and fluorescein isothiocyanate (FITC)-dextran perfusion. The genetic and expression properties of GBM cell lines were analyzed. The doughnut-hole dish assay revealed KNS1451 as the only cells to induce HUVEC transformation to vessel-like structures, similar to hLFs. The 5-lane device assay demonstrated that KNS1451 promoted the formation of a vascular network that was fully perfused, revealing the functioning luminal construction. Microarray analysis revealed that KNS1451 is a mesenchymal subtype of GBM. Using a patient-derived mesenchymal GBM cell line, mature de-novo vessel formation could be induced in HUVECs by contact-independent co-culture with GBM in a microfluidic device. These results support the development of a novel in vitro research model and provide novel insights in the neovasculogenic mechanism of GBM and may potentially facilitate the future detection of unknown molecular targets.

Update on Chemotherapeutic Approaches and Management of Bevacizumab Usage for Glioblastoma

Glioblastoma, the most common primary brain tumor in adults, has one of the most dismal prognoses in cancer. In 2009, bevacizumab was approved for recurrent glioblastoma in the USA. To evaluate the clinical impact of bevacizumab as a first-line drug for glioblastoma, two randomized clinical trials, AVAglio and RTOG 0825, were performed. Bevacizumab was found to improve progression-free survival (PFS) and was reported to be beneficial for maintaining patient performance status as an initial treatment. These outcomes led to bevacizumab approval in Japan in 2013 as an insurance-covered first-line drug for glioblastoma concurrently with its second-line application. However, prolongation of overall survival was not evinced in these clinical trials; hence, the clinical benefit of bevacizumab for newly diagnosed glioblastomas remains controversial. A recent meta-analysis of randomized controlled trials of bevacizumab combined with temozolomide in recurrent glioblastoma also showed an effect only on PFS, and the benefit of bevacizumab even for recurrent glioblastoma is controversial. Here, we discuss the clinical impact of bevacizumab for glioblastoma treatment by reviewing previous clinical trials and real-world evidence by focusing on Japanese experiences. Moreover, the efficacy and safety of bevacizumab are summarized, and we provide suggestions for updating the approaches and management of bevacizumab.

Combination Therapy by Tissue-Specific Suicide Gene and Bevacizumab in Intramedullary Spinal Cord Tumor

PURPOSE

Malignant gliomas are aggressive spinal cord tumors. In this study, we hypothesized that combination therapy using an anti-angiogenic agent, bevacizumab, and hypoxia-inducible glioblastoma-specific suicide gene could reduce tumor growth.

MATERIALS AND METHODS

In the present study, we evaluated the effect of combination therapy using bevacizumab and pEpo-NI2-SV-TK in reducing the proliferation of C6 cells and tumor growth in the spinal cord. Spinal cord tumor was generated by the injection of C6 cells into the T5 level of the spinal cord. Complexes of branched polyethylenimine (bPEI)/pEpo-NI2-SV-TK were injected into the spinal cord tumor. Bevacizumab was then administered by an intraperitoneal injection at a dose of 7 mg/kg. The anti-cancer effects of combination therapy were analyzed by histological analyses and magnetic resonance imaging (MRI). The Basso, Beattie and Bresnahan scale scores for all of the treatment groups were recorded every other day for 15 days to assess the rat hind-limb strength.

RESULTS

The complexes of bPEI/pEpo-NI2-SV-TK inhibited the viability of C6 cells in the hypoxia condition at 5 days after treatment with ganciclovir. Bevacizumab was decreased in the cell viability of human umbilical vein endothelial cells. Combination therapy reduced the tumor size by histological analyses and MRI. The combination therapy group showed improved hind-limb function compared to the other groups that were administered pEpo-NI2-SV-TK alone or bevacizumab alone.

CONCLUSION

This study suggests that combination therapy using bevacizumab with the pEpo-NI2-SV-TK therapeutic gene could be useful for increasing its therapeutic benefits for intramedullary spinal cord tumors.

Congress of neurological surgeons systematic review and evidence-based guidelines update on the role of chemotherapeutic management and antiangiogenic treatment of newly diagnosed glioblastoma in adults

QUESTION

What is the role of temozolomide in the management of adult patients (aged 65 and under) with newly diagnosed glioblastoma?

TARGET POPULATION

These recommendations apply to adult patients diagnosed with newly diagnosed glioblastoma.

RECOMMENDATION

Level I: Concurrent and post-irradiation Temozolomide (TMZ) in combination with radiotherapy and post-radiotherapy as described by Stupp et al. is recommended to improve both PFS and OS in adult patients with newly diagnosed GBM. There is no evidence that alterations in the dosing regimen have additional beneficial effect.

QUESTION

Is there benefit to adjuvant temozolomide treatment in elderly patients (> 65 years old?).

TARGET POPULATION

These recommendations apply to adult patients diagnosed with newly diagnosed glioblastoma.

RECOMMENDATION

Level III: Adjuvant TMZ treatment is suggested as a treatment option to improve PFS and OS in adult patients (over 70 years of age) with newly diagnosed GBM.

QUESTION

What is the role of local regional chemotherapy with BCNU biodegradable polymeric wafers in adult patients with newly diagnosed glioblastoma?

TARGET POPULATION

These recommendations apply to adult patients diagnosed with newly diagnosed glioblastoma.

RECOMMENDATION

Level III: There is insufficient evidence for the use of BCNU wafers following resection in patients with newly diagnosed glioblastoma who undergo the Stupp protocol after surgery. Further studies of higher quality are suggested to understand the role of BCNU wafer and other locoregional therapy in the setting of Stupp Protocol.

QUESTION

What is the role of bevacizumab in the adult patient with newly diagnosed glioblastoma?

TARGET POPULATION

These recommendations apply to adult patients diagnosed with newly diagnosed glioblastoma.

RECOMMENDATION

Level I: Bevacizumab in general is not recommended in the initial treatment of adult patients with newly diagnosed GBM. It continues to be strongly recommended that patients with newly diagnosed GBM be enrolled in properly designed clinical trials to assess the benefit of novel chemotherapeutic agents compared to standard therapy.

First-line bevacizumab contributes to survival improvement in glioblastoma patients complementary to temozolomide

INTRODUCTION

First-line bevacizumab (BEV) is now available as a treatment option for glioblastoma patients with severe clinical conditions in Japan. However, the survival benefits remain controversial. To elucidate these potential survival benefits, we retrospectively analyzed survival in glioblastoma patients receiving BEV.

METHODS

We analyzed survival in 120 patients with IDH-wild type glioblastoma treated from 2002 to 2018. Overall survival (OS) was assessed in three treatment era subgroups [pre-temozolomide (TMZ), TMZ, and TMZ-BEV], and the correlations of prognostic factors with survival were evaluated.

RESULTS

An improvement in survival was observed after BEV approval (median OS in the pre-TMZ, TMZ, and TMZ-BEV eras: 14.6, 14.9, and 22.1 months, respectively). A Cox proportional hazards model identified extent of resection and MGMT methylation status as significant prognostic factors in the TMZ era; however, these factors were not significant in the TMZ-BEV era. In subgroup analyses, patients with MGMT methylation had improved OS after TMZ introduction (pre-TMZ vs. TMZ, 18.5 vs. 28.1 months; P = 0.13), and those without MGMT methylation had significantly increased OS after BEV approval (TMZ vs. TMZ-BEV, 12.2 vs. 16.7 months; P = 0.04).

CONCLUSIONS

Our findings imply that optional first-line administration of BEV can overcome the impact of conventional risk factors and prolong survival complementary to TMZ. The patient subgroups benefitting from TMZ and BEV did not seem to overlap, and stratification based on risk factors, including MGMT methylation status, might be effective for selecting patients in whom BEV should be preferentially used as a first-line therapy.

Evaluation of the apparent diffusion coefficient in patients with recurrent glioblastoma under treatment with bevacizumab with radiographic pseudoresponse

BACKGROUND

Response Assessment in Neuro-Oncology Criteria (RANO), are used to asses response to first-line treatment of glioblastoma (GBM). Differentiation between response and pseudoresponse under treatment with Bevacizumab (BVZ) remains challenging. This study evaluates ADC changes in patients with radiographic pseudoresponse under treatment with (BVZ).

METHODS

Patients (n=40) with recurrent GBM under-treatment with BVZ underwent MRI before, two and four months after treatment with BVZ. In patients with radiological pseudoresponse (n=11), ADC analyses were performed. Areas with decreasing T1 contrast enhancement (CE) and FLAIR signal decrease were manually selected and compared to size and position matched healthy contralateral brain parenchyma.

RESULTS

Histogram based ADC (10^-6×mm²/s) of these patients decreased significantly (P<0.005) from baseline MRI (T1-CE, FLAIR: 1124.9±160.3, 1098.4±226.2, respectively) to 2months (781.3±110.7, 783.3±103.3) and remained stable during 4months (777.0±138.5, 784.4±155.4, all mean±1 SD), despite progressive disease. Mean ADC values of the healthy contralateral brain tissue remained stable (P>0.05) (ADC values: baseline: 786.2±110.7, 2months: 781.1±76.2, 4months: 804.1±86.2).

CONCLUSION

Treatment of GBM with BVZ leads to a decrease of ADC values in areas of pre-treatment T1-CE/FLAIR signal hyperintensity to levels of comparable with normal brain tissue. ADC values remained stable, even when progressive tumor growth was reported.

Ischemic stroke and intracranial hemorrhage in patients with recurrent glioblastoma multiforme, treated with bevacizumab

Bevacizumab (BVZ), a monoclonal antibody directed against vascular endothelial growth factor (VEGF), has been suspected to increase the incidence of ischemic stroke (IS) and intracranial hemorrhage (ICH) in GBM patients. Intracranial vascular events, such as IS and ICH, were retrospectively analyzed in 364 MRI scans of 82 patients with recurrent GBM (1st/2nd/3rd relapse). Out of these 82 patients, 40 were treated with BVZ (178 scans) in addition to basic treatment, whereas 42 patients matching for age and gender received basic treatment (186 scans). Distribution of typical vascular risk factors between both groups was analyzed retrospectively. In seven out of 82 patients (8%) vascular events were detected in MRI. Four vascular events were recorded in the BVZ-group (3 IS and 1 ICH), and 3 vascular events were found in the Control-group (1 IS and 2 ICH; p > 0.05 between both groups). Likewise, vascular risk factors (arterial hypertension, diabetes mellitus, obesity, former vascular event, hyperlipidemia, tobacco consumption and/or hypercholesterolemia) did not differ significantly between both groups. BVZ treatment does not seem to be associated with an increased risk for vascular events in patients with GBM in recurrence.