Prognostic factors in recurrent glioblastoma patients treated with bevacizumab

A prognostic model for overall survival in recurrent glioma patients treated with bevacizumab-containing therapy

Predictive markers and prognostic models are useful for the individualization of cancer treatment. In this study, we sought to identify clinical and molecular factors to predict overall survival in recurrent glioma patients receiving bevacizumab-containing regimens. A cohort of 102 patients was retrospectively collected from June 2011 to January 2022 at our institution. A nomogram was generated by Cox regression and feature selection algorithms based on 19 clinicopathological and 60 molecular variables. The model's performance was internally evaluated by bootstrapping in terms of discrimination and calibration. The median overall survival from the initiation of bevacizumab administration to death or last follow-up was 11.6 months (95% CI: 9.2-13.8 months) for all 102 patients, 10.2 months (95% CI: 6.4-13.3 months) for 66 patients with grade 4 tumors, and 13.8 months (lower limit of 95% CI: 11.5 months) for 36 patients with tumors of grade lower or not available. In the final model, a lower WHO 2021 grade (Grade lower or not available vs. Grade 4, HR: 0.398, 95% CI: 0.223-0.708, p = 0.00172), having received adjuvant radiochemotherapy (Yes vs. No, HR: 0.488, 95% CI: 0.268-0.888, p = 0.0189), and wildtype EGFR (Wildtype vs. Altered, HR: 0.193, 95% CI: 0.0506-0.733, p = 0.0157; Not available vs. Altered, HR: 0.386, 95% CI: 0.184-0.810, p = 0.0118) were significantly associated with longer overall survival in multivariate Cox regression. The overall concordance index was 0.652 (95% CI: 0.566-0.714), and the areas under the time-dependent curves for 6-, 12-, and 18-month overall survival were 0.677 (95% CI: 0.516-0.816), 0.654 (95% CI: 0.470-0.823), and 0.675 (95% CI: 0.491-0.860), respectively. A prognostic model for overall survival in recurrent glioma patients treated with bevacizumab-based therapy was established and internally validated. It could serve as a reference tool for clinicians to assess the extent the patients may benefit from bevacizumab and stratify their treatment response.

Use of Bevacizumab in recurrent glioblastoma: a scoping review and evidence map

BACKGROUND

Glioblastoma (GBM) is the most malignant primary tumor in the brain, with poor prognosis and limited effective therapies. Although Bevacizumab (BEV) has shown promise in extending progression-free survival (PFS) treating GBM, there is no evidence for its ability to prolong overall survival (OS). Given the uncertainty surrounding BEV treatment strategies, we aimed to provide an evidence map associated with BEV therapy for recurrent GBM (rGBM).

METHODS

PubMed, Embase, and the Cochrane Library were searched for the period from January 1, 1970, to March 1, 2022, for studies reporting the prognoses of patients with rGBM receiving BEV. The primary endpoints were overall survival (OS) and quality of life (QoL). The secondary endpoints were PFS, steroid use reduction, and risk of adverse effects. A scoping review and an evidence map were conducted to explore the optimal BEV treatment (including combination regimen, dosage, and window of opportunity).

RESULTS

Patients with rGBM could gain benefits in PFS, palliative, and cognitive advantages from BEV treatment, although the OS benefits could not be verified with high-quality evidence. Furthermore, BEV combined therapy (especially with lomustine and radiotherapy) showed higher efficacy than BEV monotherapy in the survival of patients with rGBM. Specific molecular alterations (IDH mutation status) and clinical features (large tumor burden and double-positive sign) could predict better responses to BEV administration. A low dosage of BEV showed equal efficacy to the recommended dose, but the optimal opportunity window for BEV administration remains unclear.

CONCLUSIONS

Although OS benefits from BEV-containing regimens could not be verified in this scoping review, the PFS benefits and side effects control supported BEV application in rGBM. Combining BEV with novel treatments like tumor-treating field (TTF) and administration at first recurrence may optimize the therapeutic efficacy. rGBM with a low apparent diffusion coefficient (ADCL), large tumor burden, or IDH mutation is more likely to benefit from BEV treatment. High-quality studies are warranted to explore the combination modality and identify BEV-response subpopulations to maximize benefits.

Efficacy and Safety of Bevacizumab Combined with Other Therapeutic Regimens for Treatment of Recurrent Glioblastoma: A Network Meta-analysis

BACKGROUND

Despite the fact that bevacizumab (Bev) has been approved to treat recurrent glioblastoma, patients have failed to demonstrate a significant overall survival (OS) advantage. In recent years, the advent of more Bev combination regimens seems to bring new hope for patients; nevertheless, there is still a lack of intuitive comparison among these therapies.

OBJECTIVE

To explore the efficacy and safety of various Bev combination regimens in patients with recurrent glioblastoma and to further explore the differences in the efficacy of each treatment in randomized controlled trials (RCTs) and nonrandomized controlled trials (non-RCTs).

METHODS

We comprehensively searched the PubMed, Cochrane Library, and OVID databases for relevant RCTs and non-RCTs of Bev in combined regimens for recurrent glioblastoma. The Cochrane quality assessment method was used to assess the quality of RCTs, and the Newcastle-Ottawa scale was used to assess the quality of non-RCTs. Excel software was used to extract data from the literature, and a network meta-analysis was performed using RevMan 5.3 and Stata 16 statistical software.

RESULTS

In patients with recurrent glioblastoma, the 6-month OS of patients receiving bevacizumab combination therapy was ranked from high to low as follows: Bev + rindopepimut, Bev + lomustine (CCNU), CCNU, tumor treating fields + Bev, Bev, Bev + irinotecan (Iri), Bev + temozolomide (TMZ), Bev + vorinostat, Bev + onartuzumab, Bev + dasatinib, Bev + carboplatin, Bev + trebananib, Bev + VB-111, TMZ, PCV, VB-111, and carboplatin. The 6-month progression-free survival from high to low was ranked as follows: Bev + CCNU, Bev + rindopepimut, Bev + dasatinib, Bev + vorinostat, Bev, Bev + Iri, Bev + TMZ, CCNU, Bev + carboplatin, TMZ, Bev + VB-111, PCV, Bev + trebananib, carboplatin, and VB-111. We compared the total incidence of serious adverse events (≥3) and found that Bev + vorinostat and Bev + trebananib were safer than Bev, while other regimens were not as safe as Bev. A descriptive analysis showed that Bev + rindopepimut also appeared to be safer than Bev. In subgroup analysis, among RCTs, Bev + CCNU therapy had the highest 6-month OS and 6-month progression-free survival. Among non-RCTs, Bev + Iri therapy showed the highest 6-month OS and good 6-month progression-free survival.

CONCLUSIONS

Both Bev + CCNU and Bev + rindopepimut could be considered as effective therapies for treating the recurrent glioblastoma according to the network meta-analysis results. Among them, Bev + rindopepimut therapy seems to be safer and more effective. Moreover, we found that Bev + Iri also appeared to be an effective therapy in a retrospective study.

Impact of prognostic nutritional index on survival in recurrent glioblastoma

BACKGROUND

Primary brain tumors are relatively rare malignancy, with high-grade gliomas (glioblastoma multiforme and anaplastic gliomas) are the most common types. We aimed to evaluate the prognostic value of Prognostic Nutritional Index (PNI), which is calculated by lymphocyte count and albumin, in recurrent glioblastoma patients treated with systemic treatment.

METHODS

Data of 64 patients with recurrent glioblastoma who received systemic treatment and followed in our clinic between 2012 and 2018 was retrospectively collected and analyzed. PNI was calculated as: [(10×serum albumin (g/dL))+(0.005×total lymphocyte count)]. Patients were categorized according to the median PNI value. We investigated the prognostic role of PNI groups, and survival outcomes.

RESULTS

Median value of PNI was 45.7, and median follow-up duration was 9 months (1-68 months). Median overall survival (OS) was 7.9 months (95%CI: 5.5-10.4). Median OS was significantly longer in patients with PNI>45.7 compared to patients with PNI≤45.7 (13.9 months (95%CI: 10.5-17.4), and 4.6 months (95%CI: 2.5-6.8), p<0.001, respectively). In multivariate analysis, PNI was found to be an independent prognostic factor for OS [HR:0.41 (95%CI:0.22-0.74), p=0.03)].

CONCLUSION

In our study, the PNI was found to be an independent prognostic biomarker in patients with recurrent glioblastoma, but further prospective trials are necessary to validate its prognostic role.

Neutrophil-to-lymphocyte ratio is prognostic in recurrent glioblastoma multiforme treated with bevacizumab plus irinotecan

Aim: We intended to survey the prognostic utility of pretreatment neutrophil-to-lymphocyte ratio (NLR) as a novel prognostic index in recurrent glioblastoma multiforme (R-GBMs) treated with bevacizumab plus irinotecan (BEVIRI). Patients & methods: The present retrospective investigation incorporated the R-GBMs patients who underwent BEVIRI. The pre-BEVIRI NLR was calculated for each patient by utilizing the complete blood count tests obtained on the first day of BEVIRI. Results: The data of a total of 103 patients were analyzed. The ideal cutoff was identified at 3.04 (area under the curve: 60%; sensitivity: 60.3%; specificity 60%) for the pre-BEVIRI NLR. Low-NLR group had significantly longer overall survival times than the high-NLR group (15.8 vs 9.3 months; p = 0.015). Conclusion: NLR might be utilized as a novel biomarker in the prognostic stratification of the R-GBMs treated with BEVIRI.

Impact of prognostic nutritional index on survival in recurrent glioblastoma

BACKGROUND

Primary brain tumors are relatively rare malignancy, with high-grade gliomas (glioblastoma multiforme and anaplastic gliomas) are the most common types. We aimed to evaluate the prognostic value of Prognostic Nutritional Index (PNI), which is calculated by lymphocyte count and albumin, in recurrent glioblastoma patients treated with systemic treatment.

METHODS

Data of 64 patients with recurrent glioblastoma who received systemic treatment and followed in our clinic between 2012 and 2018 was retrospectively collected and analyzed. PNI was calculated as: [(10×serum albumin (g/dL))+(0.005×total lymphocyte count)]. Patients were categorized according to the median PNI value. We investigated the prognostic role of PNI groups, and survival outcomes.

RESULTS

Median value of PNI was 45.7, and median follow-up duration was 9 months (1-68 months). Median overall survival (OS) was 7.9 months (95%CI: 5.5-10.4). Median OS was significantly longer in patients with PNI>45.7 compared to patients with PNI≤45.7 (13.9 months (95%CI: 10.5-17.4), and 4.6 months (95%CI: 2.5-6.8), p<0.001, respectively). In multivariate analysis, PNI was found to be an independent prognostic factor for OS [HR:0.41 (95%CI:0.22-0.74), p=0.03)].

CONCLUSION

In our study, the PNI was found to be an independent prognostic biomarker in patients with recurrent glioblastoma, but further prospective trials are necessary to validate its prognostic role.

Transforming approaches to treating TRK fusion cancer: historical comparison of larotrectinib and histology-specific therapies

OBJECTIVE

The results from basket trials utilized to gain regulatory approval of tumor-agnostic therapies can be difficult to interpret without the context of a comparator arm. We describe the role and efficacy of histology-based treatments to provide a historical comparison with larotrectinib.

METHODS

A systematic literature review (SLR) was conducted on the clinical outcomes of current histology-based standard of care treatments used in non-small cell lung cancer, colorectal cancer, thyroid cancer, gliomas, soft tissue sarcoma, salivary gland cancer, and infantile fibrosarcoma (7 of the 21 tumor histologies in the larotrectinib trials). The review focused on advanced stage/metastatic disease to make a historical comparison with larotrectinib.

RESULTS

Larotrectinib provides positive outcomes in both adult and pediatric patients with advanced or metastatic solid tumors known to harbor NTRK gene fusions across a wide range of tumor types. Although the numbers of patients per tumor type are limited, the results of this historical comparison demonstrated that larotrectinib is an efficacious treatment option when naïvely indirectly compared with historical treatments across all 7 reviewed tumor types, especially in comparison to later lines of therapy.

CONCLUSIONS

Utilizing larotrectinib as a case example across these types of historical comparisons shows that larotrectinib provides positive efficacy outcomes in TRK fusion cancer across tumor histologies known to harbor NTRK gene fusions that may be preferable to historical treatments.

Prognostic value of modified Glasgow prognostic score in recurrent high-grade glial tumors treated with systemic treatment

OBJECTIVES

Malignant high-grade gliomas are the most common and aggressive type of primary brain tumor. We aimed to evaluate the prognostic value of modified Glasgow Prognostic Score (mGPS), which is combination of C-reactive protein (CRP) and albumin, in recurrent high-grade glioma patients treated with systemic treatment.

PATIENTS AND METHODS

Data of 85 patients with recurrent high-grade glioma who received systemic treatment and followed in our clinic between 2012 and 2018 was retrospectively collected and analyzed. Patients were grouped according to mGPS criteria: mGPS-0: CRP < 10 mg/L and albumin >3.5 g/dL; mGPS-1: CRP < 10 mg/L and albumin <3.5 g/dL or CRP > 10 mg/L and albumin >3.5 g/dL; and mGPS-2: CRP > 10 mg/L and albumin <3.5 mg/L. We investigated the prognostic role of mGPS groups, mutations and survival outcomes.

RESULTS

There were 42 (49.4 %), 25 (29.6 %), and 18 (21 %) patients in mGPS-0, mGPS-1, and mGPS-2 groups, respectively. Median follow-up duration was 10 months (1-70 months). Median OS was 8.1 months. According to mGPS-0, -1 and -2; median OS was 13.8 months, 7.3 months and 3.6 months respectively (p = 0.003). mGPS, ATRX and IDH-1 mutation status, and ECOG PS were found to be independent prognostic factors for OS.

CONCLUSION

In our study, mGPS was found to be an independent prognostic factor in patients with recurrent high-grade gliomas. If validated, mGPS can be used as an objective, easily calculated, cheap, and readily available prognostic model in routine practice.

Prognostic factors in progressive high-grade glial tumors treated with systemic approach: A single center experience

PURPOSE

Malignant high-grade gliomas are the most common and aggressive type of primary brain tumor, and the prognosis is generally extremely poor. In this retrospective study, we analyzed the outcome of systemic treatment in recurrent high-grade glioma patients and the impact of prognostic factors on survivals.

METHODS

Data from 114 patients with recurrent high-grade glioma who received systemic treatment and followed in our clinic between 2012 and 2018 were retrospectively analyzed. Eastern Cooperative Oncology Group (ECOG) performance status, age, gender, histology, type of surgical resection, side effects after systemic treatment (deep vein thrombosis, hypertension, proteinuria), IDH1 and alpha thalassemia/mental retardation syndrome X-linked (ATRX) mutation status were investigated as prognostic factors for progression-free survival and overall survival.

RESULTS

At the time of diagnosis, the median age was 48 (17-77) and 68% of the patients were male. Most common pathologic subtype was glioblastoma multiforme (68%). Median follow-up duration was 9.1 months (1-68 months). Median progression-free survival and overall survival were 6.2 months and 8 months, respectively. In multivariate analysis, ECOG PS, deep venous thrombosis and the presence of ATRX and IDH1 mutation were found to be independent prognostic factors for progression-free survival (p < 0.05) and, ECOG PS, the presence of ATRX and IDH1 mutation for overall survival (p < 0.05).

CONCLUSION

Our study is real life data and the median progression-free survival and overall survival rates are similar to the literature. We have found ECOG PS, presence of ATRX and IDH1 mutation to be independent prognostic factors for both progression-free survival and overall survival.

Long-term survival in patients with recurrent glioblastoma treated with bevacizumab: a multicentric retrospective study

PURPOSE

Recurrence of glioblastoma (GB) occurs in most patients after standard concomitant temozolomide-based radiochemotherapy (CTRC). Bevacizumab (BV), an anti-VEGF antibody, has an effect on progression-free survival (PFS) but not on overall survival (OS). However, a small part of the patients experience a survival, longer than expected. This retrospective study aims to characterize long responder (LR) patients treated with BV for a first or second GBM recurrence.

METHODS

Medical records from patients (814) who received BV for a first or second recurrence of primary glioblastoma between September 2010 and September 2015, and initially treated by CTRC were analyzed. Patients, who had at least a stable disease according to RANO criteria at 12 months from the start of BV, were included. Patients who had, a secondary GB, or received BV in neoadjuvant or adjuvant setting were excluded.

RESULTS

We focused on 65 LR patients without progression 12 months after the first injection of BV (8%). Median PFS was 21.7 months [95% CI (19.3; 27.2)] and median OS was 31.1 months [95% CI (24.3; 37.5)] from the start of BV. No prognostic factor was associated with OS in multivariate analysis. Karnofsky performance status, neurological status and corticosteroid dose were stable at 12 months.

CONCLUSIONS

Our results highlight that among patients receiving bevacizumab in first or second recurrence, one patient out of twelve could be classified as LR. A median OS of 31.1 months from the start of BV could be expected in this subpopulation. These findings reinforce the potential benefit of the use of BV in the situation of recurrence. 256 words.

EGFR amplification and classical subtype are associated with a poor response to bevacizumab in recurrent glioblastoma

PURPOSE

The highly vascular malignant brain tumor glioblastoma (GBM) appears to be an ideal target for anti-angiogenic therapy; however, clinical trials to date suggest the VEGF antibody bevacizumab affects only progression-free survival. Here we analyze a group of patients with GBM who received bevacizumab treatment at recurrence and are stratified according to tumor molecular and genomic profile (TCGA classification), with the goal of identifying molecular predictors of the response to bevacizumab.

METHODS

We performed a retrospective review of patients with a diagnosis of glioblastoma who were treated with bevacizumab in the recurrent setting at our hospital, from 2006 to 2014. Treatment was discontinued by the treating neuro-oncologists, based on clinical and radiographic criteria. Pre- and post-treatment imaging and genomic subtype were available on 80 patients. We analyzed time on bevacizumab and time to progression. EGFR gene amplification was determined by FISH.

RESULTS

Patients with classical tumors had a significantly shorter time on bevacizumab than mesenchymal, and proneural patients (2.7 vs. 5.1 vs. 6.4 and 6.0 months respectively, p = 0.011). Classical subtype and EGFR gene amplification were significantly associated with a shorter time to progression both in univariate (p < 0.001 and p = 0.007, respectively) and multivariate analysis (both p = 0.010).

CONCLUSION

EGFR gene amplification and classical subtype by TCGA analysis are associated with significantly shorter time to progression for patients with recurrent GBM when treated with bevacizumab. These findings can have a significant impact on decision-making and should be further validated prospectively.

Quantitative imaging biomarkers for risk stratification of patients with recurrent glioblastoma treated with bevacizumab

Background

Anti-angiogenic therapy with bevacizumab is the most widely used treatment option for recurrent glioblastoma, but therapeutic response varies substantially and effective biomarkers for patient selection are not available. To this end, we determine whether novel quantitative radiomic strategies on the basis of MRI have the potential to noninvasively stratify survival and progression in this patient population.

Methods

In an initial cohort of 126 patients, we identified a distinct set of features representative of the radiographic phenotype on baseline (pretreatment) MRI. These selected features were evaluated on a second cohort of 165 patients from the multicenter BRAIN trial with prospectively acquired clinical and imaging data. Features were evaluated in terms of prognostic value for overall survival (OS), progression-free survival (PFS), and progression within 3, 6, and 9 months using baseline imaging and first follow-up imaging at 6 weeks posttreatment initiation.

Results

Multivariable analysis of features derived at baseline imaging resulted in significant stratification of OS (hazard ratio [HR] = 2.5; log-rank P = 0.001) and PFS (HR = 4.5; log-rank P = 2.1 × 10-5) in validation data. These stratifications were stronger compared with clinical or volumetric covariates (permutation test false discovery rate [FDR] <0.05). Univariable analysis of a prognostic textural heterogeneity feature (information correlation) derived from postcontrast T1-weighted imaging revealed significantly higher scores for patients who progressed within 3 months (Wilcoxon test P = 8.8 × 10-8). Generally, features derived from postcontrast T1-weighted imaging yielded higher prognostic power compared with precontrast enhancing T2-weighted imaging.

Conclusion

Radiomics provides prognostic value for survival and progression in patients with recurrent glioblastoma receiving bevacizumab treatment. These results could lead to the development of quantitative pretreatment biomarkers to predict benefit from bevacizumab using standard of care imaging.

Improvement of health related quality of life in patients with recurrent glioma treated with bevacizumab plus daily temozolomide as the salvage therapy

OBJECTIVES

Bevacizumab (BEV) plus daily temozolomide (TMZ) as a salvage therapy have been recommended to recurrent glioma. The objective of this retrospective study was to evaluate the effect of the combined regimen on health related quality of life (HRQL) and treatment response in patients with recurrent glioma.

PATIENTS AND METHODS

Twenty patients with recurrent glioma were treated with BEV (5-10 mg/kg, i.v. every 2 weeks) plus daily TMZ (daily, 50 mg/m²). The treatment response was evaluated via the RANO criteria. HRQL were measured using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire core 30 (QLQ-C30) and Brain Module (QLQ-BN20).

RESULTS

Twenty patients received a total of 85 cycles of BEV with a median number of 4 cycles (range: 2-10). No patients showed complete response (CR) to treatment. Twelve patients had partial response (PR), stable disease (SD) in 5 patients with, and 3 patients showed progressive disease (PD). In the functioning domains of QLQ-C30, physical functioning, cognitive functioning and emotional functioning significantly improved after the second cycle of BEV compared to baseline, with the mean score of 45.0 vs. 64.0 (p = 0.020), 55.8 vs. 71.7 (p = 0.020) and 48.3 vs. 67.5 (p = 0.015), respectively. In the symptom scales, the scores of pain and nausea/vomiting significantly decreased compared to baseline from the mean score of 39.1 to 20.0 (p = 0.020) and 29.2 to 16.7 (p = 0.049), respectively. Score of global health status also increased from 47.5 to 63.3 (p = 0.001). As determined with the QLQ-BN20, motor dysfunction (43.3 vs. 25.0, p = 0.021), weakness of legs (36.7 vs. 18.3, p = 0.049), headache (38.3 vs. 20.0, p = 0.040), and drowsiness (50.0 vs. 30.0, p = 0.026) after the second cycle of BEV also significantly improved compared to baseline.

CONCLUSION

BEV plus daily TMZ as a salvage therapy improved HRQL in patients with recurrent glioma.

The Clinical Significance of O6-Methylguanine-DNA Methyltransferase Promoter Methylation Status in Adult Patients With Glioblastoma: A Meta-analysis

Background and objective

Promoter status of O⁶-methylguanine-DNA methyltransferase (MGMT) has been widely established as a clinically relevant factor in glioblastoma (GBM) patients. However, in addition to varied therapy schedule, the prognosis of GBM patients is also affected by variations of age, race, primary or recurrent tumor. This study comprehensively investigated the association between MGMT promoter status and prognosis in overall GBM patients and in different GBM subtype including new diagnosed patients, recurrent patients and elderly patients.

Methods

A comprehensive search was performed using PubMed, EMBASE, Cochrane databases to identify literatures (published from January 1, 2005 to April 1, 2017) that evaluated the associations between MGMT promoter methylation and prognosis of GBM patients.

Results

Totally, 66 studies including 7,886 patients met the inclusion criteria. Overall GBM patients with a methylated status of MGMT receiving temozolomide (TMZ)-containing treatment had better overall survival (OS) and progression-free survival (PFS) [OS: hazard ratio (HR) = 0.46, 95% confidence interval (CI): 0.41–0.52, p < 0.001, Bon = 0.017; PFS: HR = 0.48, 95% CI 0.40–0.57, p < 0.001, Bon = 0.014], but no significant advantage on OS or PFS in GBM patients with TMZ-free treatment was observed (OS: HR = 0.97, 95% CI 0.91–1.03, p = 0.08, Bon = 1; PFS: HR = 0.76, 95% CI 0.57–1.02, p = 0.068, Bon = 0.748). These different impacts of MGMT status on OS were similar in newly diagnosed GBM patients, elderly GBM patients and recurrent GBM. Among patients receiving TMZ-free treatment, survival benefit in Asian patients was not observed anymore after Bonferroni correction (Asian OS: HR = 0.78, 95% CI 0.64–0.95, p = 0.02, Bon = 0.24, I² = 0%; PFS: HR = 0.69, 95% CI 0.50–0.94, p = 0.02, Bon = 0.24). No benefit was observed in Caucasian receiving TMZ-free therapy regardless of Bonferroni adjustment.

Conclusion

The meta-analysis highlights the universal predictive value of MGMT methylation in newly diagnosed GBM patients, elderly GBM patients and recurrent GBM patients. For elderly methylated GBM patients, TMZ alone therapy might be a more suitable option than radiotherapy alone therapy. Future clinical trials should be designed in order to optimize therapeutics in different GBM subpopulation.

Bevacizumab for Patients with Recurrent Multifocal Glioblastomas

In patients with glioblastoma, antiangiogenic therapy with bevacizumab (BEV) has been shown to improve progression-free survival (PFS), but not overall survival (OS). Especially in patients with an unusual infiltrative phenotype as seen in multifocal glioblastoma, the use of BEV therapy is still more controversial. Therefore, we prepared a retrospective case series with 16 patients suffering from a multifocal glioblastoma treated with BEV. We compared these patients to a matched control cohort of 16 patients suffering from glioblastoma with a single lesion treated with BEV. The objective of this study was to evaluate whether the course of disease differs in glioblastoma patients with a multifocal disease pattern compared to those with a single lesion only. Patients were treated with BEV monotherapy or BEV in combination with irinotecan or lomustine (CCNU). Response rates and PFS were similar in both groups. There was a trend for an unfavorable OS in the patient group with multifocal glioblastoma, which was expected due to the generally worse prognosis of multifocal glioblastoma. We investigated whether BEV therapy affects the invasive growth pattern as measured by the appearance of new lesions on magnetic resonance imaging (MRI). Under BEV therapy, there was a trend for a lower frequency of new lesions both in multifocal and solitary glioblastoma. Based on these results, BEV therapy at relapse appears to be justified to no lesser extent in multifocal glioblastoma than in solitary glioblastoma.

Bevacizumab as a last-line treatment for glioblastoma following failure of radiotherapy, temozolomide and lomustine

In previous trials, bevacizumab failed to prolong the overall survival time in newly diagnosed glioblastoma and at the first recurrence. Randomized clinical trials at the second or further recurrence following the failure of radiotherapy, temozolomide and lomustine, and retrospective analyses focusing on this specific cohort, are not yet available. A total of 62 patients with glioblastoma who received bevacizumab after the failure of standard care, including radiotherapy, temozolomide and lomustine, were retrospectively identified. Patient characteristics, previous treatment details, concomitant therapy, response based on the Response Assessment in Neuro-Oncology criteria, and progression-free survival (PFS) and overall survival (OS) times and rates were evaluated. Furthermore, the PFS and OS times and rates were analyzed for responders and non-responders. Of the patients, 54.8% (n=34) responded to treatment [complete response (CR) 3.2%, n=2; partial response (PR) 51.6%, n=32]. The median PFS time was 3.5 months and the median OS time was 7.5 months. The PFS rate at 6 months was 21.5% and the OS rate at 12 months was 11.5%. Responders (CR or PR) experienced a superior median PFS time compared with non-responders (i.e. stable or progressive disease; 5.4 vs. 1.9 months; P<0.0001) and a superior PFS rate at 6 months (34.9 vs. 7.1%; P<0.0001). The median OS time (8.6 vs. 6.4 months; P<0.0001) and OS rate at 12 months (21.3 vs. 0%; P<0.0001) were also superior in patients who exhibited a response to bevacizumab treatment. In conclusion, the objective response rate and the PFS and OS times and rates indicate that bevacizumab has activity in patients with glioblastoma following the failure of radiotherapy, temozolomide, and lomustine. A randomized trial comparing bevacizumab with best supportive care in these patients is advised.

Laser Ablation of Recurrent Malignant Gliomas

Recurrent malignant glioma continues to be a clinical challenge, and repeat surgery is an option in only select patients. Stereotactic laser ablation, a new minimally invasive technique, can be used as an alternative to surgery. We review the current literature on laser ablation for recurrent malignant gliomas as well as discuss practical and theoretical advantages and disadvantages of this emerging technique in comparison with repeat surgery or radiation. We also discuss the potential for laser ablation to augment adjuvant therapies, namely, chemotherapy, radiation, and immunotherapy.

The earlier the better? Bevacizumab in the treatment of recurrent MGMT-non-methylated glioblastoma

PURPOSE

The adequate second-line therapy of patients with glioblastoma (GBM) is a matter of ongoing debate. This particularly applies to patients with a non-methylated MGMT promotor who are known to have a poor response to alkylating chemotherapy. In some countries, antiangiogenic therapy with BEV is applied as second-line therapy, and in others nitrosourea therapy is second-line choice. It is an open question whether the delay of BEV to third-line therapy has a negative impact on survival.

METHODS

A total of 61 adult patients (median age 56.9 years) with MGMT-non-methylated relapsed GBM treated with BEV (n = 45) or nitrosourea (n = 16) as second-line therapy were analyzed retrospectively and compared regarding progression-free survival (PFS) and overall survival (OS).

RESULTS

Patients treated with second-line BEV had longer median PFS (107 days, 95 % CI 80.7-133.2 days) than patients with second-line nitrosourea (52 days, 95 % CI 36.3-67.7 days, P = 0.011, logrank test). However, there was no significant difference in overall survival (BEV median 170 days, 95 % CI 87.2-252.8 days; nitrosourea median 256 days, 95 % CI 159.9-352.0 days, P = 0.468). PFS was similar after BEV third-line therapy (median 117 days, 95 % CI 23.6-210.4 days) as compared to second-line BEV therapy (median 107 days, 95 % CI 80.7-133.3 days, P = 0.584).

CONCLUSION

Our findings suggest that early treatment with BEV in patients with MGMT-non-methylated relapsed GBM is associated with a better PFS, but not with superior OS, possibly implicating that the early, i.e., second-line, use of BEV is not mandatory and BEV treatment may safely be delayed to third-line therapy in this subgroup of patients.