Reoperation in the treatment of recurrent intracranial malignant gliomas

Stereotactic radiosurgery versus combined stereotactic radiosurgery and bevacizumab for recurrent glioblastoma; a systematic review and meta-analysis of survival

Recurrent glioblastoma (rGBM) is a brain tumor that is resistant to standard treatments. Although stereotactic radiosurgery (SRS) is a non-invasive radiation technique, it cannot fully prevent tumor recurrence and progression. Bevacizumab blocks tumor blood supply and has been approved for rGBM. However, the best way to combine SRS and bevacizumab is still unclear. We did a systematic review and meta-analysis of studies comparing SRS alone and SRS plus bevacizumab for rGBM. We searched three databases for articles published until June 2023. All statistical analysis was performed by STATA v.17. Our meta-analysis included 20 studies with 926 patients. We found that the combination therapy had a significantly lower rate of overall survival (OS) than SRS alone at 6-month 0.77[95%CI:0.74-0.85] for SRS alone and (100%) for SRS plus bevacizumab. At 1-year OS, 0.39 [95%CI: 0.32-0.47] for SRS alone and 0.61 [95%CI:0.44-0.77] for SRS plus bevacizumab (P-value:0.02). However, this advantage was not seen in the long term (18 months and two years). Additionally, the combination therapy had lower chances of progression-free survival (PFS) than SRS alone at the 6-month and 1-year time points, but the differences were insignificant. Our study indicates that incorporating bevacizumab with SRS may lead to a short-term increase in OS for rGBM patients but not long-term. Additionally, the PFS rate did not show significant improvement in the group receiving combination therapy. Further clinical trials are necessary to validate the enhanced overall survival with combination therapy for rGBM.

Prognostic factors to predict postoperative survival in patients with recurrent glioblastoma

Background

There are no generally accepted criteria for selecting patients with recurrent glioblastoma for surgery. This retrospective study in a Danish population-based cohort aimed to identify prognostic factors affecting postoperative survival after repeated surgery for recurrent glioblastoma and to test if the preoperative New Scale for Recurrent Glioblastoma Surgery (NSGS) developed by Park CK et al could assist in the selection of patients for repeat glioblastoma surgery.

Methods

Clinical data from 66 patients with recurrent glioblastoma and repeated surgery were analyzed. Kaplan-Meier plots were produced to illustrate survival in each of the three NSGS prognostic groups, and Cox proportional hazard regression was used to identify prognostic variables. Multivariable analysis was used to identify differences in survival in the three prognostic groups.

Results

Six variables significantly affected postoperative survival: preoperative Karnofsky Performance Status (KPS) < 70 (p = 0.002), decreased KPS after second surgery (p = 0.012), ependymal involvement (p = 0.002), tumor volume ≧ 50 cm3 (p = 0.021), age (p = 0.033) and Ki-67 (p = 0.005). Retrospective application of the criteria previously published by Park CK et al showed that median postoperative survival for the three prognostic groups was 390 days (0 points), 279 days (1 point), and 80 days (2 points), respectively.

Conclusion

Several prognostic variables to predict postoperative survival in patients with recurrent glioblastoma were identified and should be considered when selecting patient for repeat surgery. The NSGS scoring system was useful as there were significant differences in postoperative survival between its three prognostic groups.

Second surgery for relapsed glioblastoma: an observational study on criteria for patient selection in real life

Aim: There is little consensus on salvage management of glioblastoma after recurrence, for lack of evidence.Materials & methods: A retrospective study of treatments in patients with recurrent glioblastoma.Results: Surgery at recurrence was related to better overall survival (OS) and progression-free survival (PFS). Surgery at recurrence, Karnofsky index, MGMT methylation status, younger age at diagnosis and number of chemotherapy cycles were positive factors for OS and PFS. The benefit of OS was relevant for a second surgery performed at least 9 months after the first one. Systemic treatments after the second surgery were linked to an improved PFS.Conclusion: Younger age, Karnofsky index, MGMT methylation status and a median time between surgeries ≥9 months may be criteria for eligibility for surgery at recurrence.

Multiple surgical resections for progressive IDH wildtype glioblastoma-is it beneficial?

PURPOSE

The role of repeat resection for recurrent glioblastoma (rGB) remains equivocal. This study aims to assess the overall survival and complications rates of single or repeat resection for rGB.

METHODS

A single-centre retrospective review of all patients with IDH-wildtype glioblastoma managed surgically, between January 2014 and January 2022, was carried out. Patient survival and factors influencing prognosis were analysed, using Kaplan-Meier and Cox regression methods.

RESULTS

Four hundred thirty-two patients were included, of whom 329 underwent single resection, 83 had two resections and 20 patients underwent three resections. Median OS (mOS) in the cohort who underwent a single operation was 13.7 months (95% CI: 12.7-14.7 months). The mOS was observed to be extended in patients who underwent second or third-time resection, at 22.9 months and 44.7 months respectively (p < 0.001). On second operation achieving > 95% resection or residual tumour volume of < 2.25 cc was significantly associated with prolonged survival. There was no significant difference in overall complication rates between primary versus second (p = 0.973) or third-time resections (p = 0.312). The use of diffusion tensor imaging (DTI) guided resection was associated with reduced post-operative neurological deficit (RR 0.37, p = 0.002), as was use of intraoperative ultrasound (iUSS) (RR 0.45, p = 0.04).

CONCLUSIONS

This study demonstrates potential prolongation of survival for rGB patients undergoing repeat resection, without significant increase in complication rates with repeat resections. Achieving a more complete repeat resection improved survival. Moreover, the use of intraoperative imaging adjuncts can maximise tumour resection, whilst minimising the risk of neurological deficit.

Evaluation of the Diagnostic Performance of F18-Fluorodeoxyglucose-Positron Emission Tomography, Dynamic Susceptibility Contrast Perfusion, and Apparent Diffusion Coefficient in Differentiation between Recurrence of a High-grade Glioma and Radiation Necrosis

Background

Differentiation between recurrence of brain tumor and radiation necrosis remains a challenge in current neuro-oncology practice despite recent advances in both radiological and nuclear medicine techniques.

Purpose

The purpose of this study was to compare the diagnostic performance of dynamic susceptibility contrast (DSC) perfusion magnetic resonance imaging (MRI), apparent diffusion coefficient (ADC) derived from diffusion-weighted imaging, and F18-fluorodeoxyglucose-positron emission tomography (F18-FDG-PET) in the differentiation between the recurrence of a high-grade glioma and radiation necrosis.

Materials and Methods

Patients with a diagnosis of high-grade glioma (WHO Grades III and IV) who had undergone surgical resection of the tumor followed by radiotherapy with or without chemotherapy were included in the study. DSC perfusion, diffusion-weighted MRI, and PET scan were acquired on a hybrid PET/MRI scanner. For each lesion, early and delayed tumor-to-brain ratio (TBR), early and delayed maximum standardized uptake value (SUVmax), normalized ADC ratio, and normalized relative cerebral blood volume (rCBV) ratio were calculated and the pattern of lesional enhancement was noted. The diagnosis was finalized with either histopathological examination or the characteristics on follow-up imaging. The statistical analysis using the receiver operator characteristic curves was done to determine the diagnostic performance of DSC perfusion, 18-F FDG-PET, and ADC in differentiation between tumor recurrence and radiation necrosis.

Results

Fifty patients were included in the final analysis, 32 of them being men (64%). A cutoff value of early TBR >0.8 (sensitivity of 100% and specificity of 80%), delayed TBR >0.93 (sensitivity of 92.3% and specificity of 80%), early SUVmax >10.2 (sensitivity of 76.9% and specificity of 80%), delayed SUVmax >13.2 (sensitivity of 61.54% and specificity of 100%), normalized rCBV ratio >1.21 (sensitivity of 100% and specificity of 60%), normalized ADC ratio >1.66 (sensitivity of 38.5% and specificity of 80%), and Grade 3 enhancement (sensitivity of 100% and specificity of 60%) were found to differentiate recurrence from radiation necrosis. Early TBR had the highest accuracy (94.44%), while ADC ratio had the lowest accuracy (50%). A combination of early TBR (cutoff value of 0.8), late TBR (cutoff value of 0.93), and rCBV ratio (cutoff value of 1.21) showed a sensitivity of 100%, specificity of 92.3%, positive predictive value of 88.9%, negative predictive value of 93.7%, and an accuracy of 96.6% in discrimination between radiation necrosis and recurrence of tumor.

Conclusion

F18-FDG-PET and DSC perfusion can reliably differentiate tumor recurrence from radiation necrosis, with early TBR showing the highest accuracy. ADC demonstrates a low sensitivity, specificity, and accuracy in differentiating radiation necrosis from recurrence. A combination of early TBR, delayed TBR, and rCBV may be more useful in discrimination between radiation necrosis and recurrence of glioma, with this combination showing a better diagnostic performance than individual parameters or any other combination of parameters.

GammaTile® brachytherapy in the treatment of recurrent glioblastomas

Background

GammaTile® (GT) is a recent U.S. Food and Drug Administration (FDA) cleared brachytherapy platform. Here, we report clinical outcomes for recurrent glioblastoma patients after GT treatment following maximal safe resection.

Methods

We prospectively followed twenty-two consecutive Isocitrate Dehydrogenase (IDH) wild-type glioblastoma patients (6 O⁶-Methylguanine-DNA methyltransferase methylated (MGMTm); sixteen MGMT unmethylated (MGMTu)) who underwent maximal safe resection of recurrent tumor followed by GT placement.

Results

The cohort consisted of 14 second and eight third recurrences. In terms of procedural safety, there was one 30-day re-admission (4.5%) for an incisional cerebrospinal fluid leak, which resolved with lumbar drainage. No other wound complications were observed. Six patients (27.2%) declined in Karnofsky Performance Score (KPS) after surgery due to worsening existing deficits. One patient suffered a new-onset seizure postsurgery (4.5%). There was one (4.5%) 30-day mortality from intracranial hemorrhage secondary to heparinization for an ischemic limb. The mean follow-up was 733 days (range 279–1775) from the time of initial diagnosis. Six-month local control (LC₆) and twelve-month local control (LC₁₂) were 86 and 81%, respectively. Median progression-free survival (PFS) was comparable for MGMTu and MGMTm patients (~8.0 months). Median overall survival (OS) was 20.0 months for the MGMTu patients and 37.4 months for MGMTm patients. These outcomes compared favorably to data in the published literature and an independent glioblastoma cohort of comparable patients without GT treatment.

Conclusions

This clinical experience supports GT brachytherapy as a treatment option in a multi-modality treatment strategy for recurrent glioblastomas.

The current landscape of systemic therapy for recurrent glioblastoma: A systematic review of randomized-controlled trials

AIM

Conduct a systematic review of the effectiveness of systemic therapies for adult recurrent glioblastoma (rGBM).

METHODS

We electronically searched for randomized controlled trials from three major databases and four conferences from 2009-Dec 2020. Two independent reviewers conducted screening, data extraction, and quality assessment.

RESULTS

48 randomized trials were identified. Outcome reporting was inconsistent: overall survival (OS) in 46 studies, progression free survival in 37 studies, 6-month PFS in 30 studies, objective response rate in 28 studies, and 6-month OS in 7 studies. Network meta-analysis was not feasible due to heterogeneity in outcome reporting and single-study linkages. Most studies compared lomustine (8 studies), bevacizumab (18), or temozolomide (8) with other treatments. The median OS across all studies ranged from 3 to 17.6 months.

CONCLUSIONS

Based on level one evidence, there is no superior systemic regimen for rGBM. rGBM is a heterogeneous population with no single regimen demonstrating OS benefit. Registration number: CRD42020148512.

LINC00511 facilitates Temozolomide resistance of glioblastoma cells via sponging miR-126-5p and activating Wnt/β-catenin signaling

Temozolomide (TMZ) is the first-line chemotherapy drug for glioblastoma (GBM) but acquired TMZ resistance is frequently observed. Thus, a TMZ resistant GBM cell line U87-R was established to search for potential long noncoding RNAs (lncRNAs) used in TMZ resistance. In our study, LINC00511 was identified as a TMZ resistance-associated lncRNA in U87-R cells by transcriptome RNA sequencing. The potential functions of LINC00511 were evaluated by quantitative real-time polymerase chain reaction, cell viability assay, colony formation assay, western blot, soft agar assay, flow cytometry, tumor xenograft model, immunofluorescence, sphere formation assay, fluorescent in situ hybridization, luciferase reporter assay, and RNA pull-down assay. We found that LINC00511 was upregulated in U87-R cells and GBM samples, and correlated with poor prognosis of GBM patients. Silencing LINC00511 impaired TMZ tolerance of U87-R cells, while LINC00511 overexpression increased TMZ resistance of sensitive GBM cells. Wnt/β-catenin signaling was activated in U87-R cells, and inhibiting Wnt/β-catenin signaling enhanced TMZ sensitivity. Furthermore, LINC00511 was mainly distributed in the cytoplasm of GBM cells and regulated Wnt/β-catenin activation by acting as a molecular sponge for miR-126-5p. Multiple genes of Wnt/β-catenin signaling such as DVL3, WISP1, and WISP2 were targeted by miR-126-5p. MiR-126-5p restoration impaired TMZ resistance of GBM cells. In conclusion, our results provided a novel insight into acquired TMZ resistance of GBM cells and suggested LINC00511 as a potential biomarker or therapeutic target for GBM patients.

Laser Interstitial Thermal Therapy for Recurrent Glioblastoma: Pooled Analyses of Available Literature

OBJECTIVE/BACKGROUND

The efficacy of laser interstitial thermal therapy (LITT) in recurrent glioblastoma (rGBM) is unknown. The goal of this study was to conduct a systematic review and pooled analysis of the literature for outcomes on patients with rGBM undergoing LITT.

METHODS

A literature search was performed to retrieve all studies investigating overall survival, postprocedure survival, and progression-free survival outcomes of patients with rGBM undergoing LITT. Statistics were pooled together by meta-analysis of mean using a weighted random-effects or fixed-effect model.

RESULTS

Eleven studies were included in the final cohort, representing a total of 134 patients with rGBM. The pooled mean age of the cohort at the time of recurrence was 56.7 ± 4.56 years; 41% of the cohort were female. For delivery of LITT, 2 studies used neodymium-yttrium aluminum-garnet laser (Nd:YAG laser), 3 studies used the Visualase system, 5 studies used the NeuroBlate system, and 1 study used both the NeuroBlate and the Visualase system. A total of 8 studies with 107 patients had available data for overall median survival. The pooled overall survival was found to be 18.6 months (95% confidence interval [CI] 16.2-21.1). A total of 6 studies with 93 patients had available data for post-LITT survival. The pooled post-LITT survival was found to be 10.1 months (95% CI 8.8-11.6). A total of 8 studies with 119 patients had available data for progression-free survival. Pooled progression free survival was found to be 6 months (95% CI 5.3-6.7).

CONCLUSIONS

LITT is a novel minimally invasive procedure which, when used with optimal adjuvant therapy, may confer survival benefit for patients with rGBM.

The Fibronectin Expression Determines the Distinct Progressions of Malignant Gliomas via Transforming Growth Factor-Beta Pathway

Due to the increasing incidence of malignant gliomas, particularly glioblastoma multiforme (GBM), a simple and reliable GBM diagnosis is needed to screen early the death-threaten patients. This study aimed to identify a protein that can be used to discriminate GBM from low-grade astrocytoma and elucidate further that it has a functional role during malignant glioma progressions. To identify proteins that display low or no expression in low-grade astrocytoma but elevated levels in GBM, glycoprotein fibronectin (FN) was particularly examined according to the mining of the Human Protein Atlas. Web-based open megadata minings revealed that FN was mainly mutated in the cBio Cancer Genomic Portal but dominantly overexpressed in the ONCOMINE (a cancer microarray database and integrated data-mining platform) in distinct tumor types. Furthermore, numerous different cancer patients with high FN indeed exhibited a poor prognosis in the PrognoScan mining, indicating that FN involves in tumor malignancy. To investigate further the significance of FN expression in glioma progression, tumor specimens from five malignant gliomas with recurrences that received at least two surgeries were enrolled and examined. The immunohistochemical staining showed that FN expression indeed determined the distinct progressions of malignant gliomas. Furthermore, the expression of vimentin (VIM), a mesenchymal protein that is strongly expressed in malignant cancers, was similar to the FN pattern. Moreover, the level of epithelial-mesenchymal transition (EMT) inducer transforming growth factor-beta (TGF-β) was almost recapitulated with the FN expression. Together, this study identifies a protein FN that can be used to diagnose GBM from low-grade astrocytoma; moreover, its expression functionally determines the malignant glioma progressions via TGF-β-induced EMT pathway.

Radioresistance in Glioblastoma and the Development of Radiosensitizers

Ionizing radiation is a common and effective therapeutic option for the treatment of glioblastoma (GBM). Unfortunately, some GBMs are relatively radioresistant and patients have worse outcomes after radiation treatment. The mechanisms underlying intrinsic radioresistance in GBM has been rigorously investigated over the past several years, but the complex interaction of the cellular molecules and signaling pathways involved in radioresistance remains incompletely defined. A clinically effective radiosensitizer that overcomes radioresistance has yet to be identified. In this review, we discuss the current status of radiation treatment in GBM, including advances in imaging techniques that have facilitated more accurate diagnosis, and the identified mechanisms of GBM radioresistance. In addition, we provide a summary of the candidate GBM radiosensitizers being investigated, including an update of subjects enrolled in clinical trials. Overall, this review highlights the importance of understanding the mechanisms of GBM radioresistance to facilitate the development of effective radiosensitizers.

Assessing the efficacy of repeat resections in recurrent glioblastoma: a systematic review

BACKGROUND

The inevitable recurrence of glioblastoma (GBM) results in patients often undergoing multiple resections with questionable benefit to overall survival (OS).

OBJECTIVE

To systematically review and analyze prior studies examining the potential added benefit of repeat resection (RR) in recurrent GBM.

METHODS

We performed a PRISMA-compliant systematic review of literature published between 1969 to 2019 involving patients undergoing RR at GBM recurrence.

RESULTS

The search yielded 3994 non-duplicate citations. Final abstraction included 43 articles, with 2 level II and 41 level III studies. The earliest paper we included was published in 1987 [1], and 35 identified papers (81.4%) were published within the last 10 years. The survival data of 9236 patients (55% male) were analyzed, with a median age of 56; 3726 patients underwent RR. In 31 studies with a comparable single-surgery-only cohort, 20 articles reported a statistically significant increase in OS with RR, 7 reported nonsignificant trends toward increased OS with RR, and 4 reported no significant increase in OS with RR. Twenty-two articles with multivariate analyses of Karnofsky performance scores and 17 articles with extent-of-resection reported these as significant prognostic factors of OS. In 26 studies, median OS among all patients was 17.85 months inclusive of median OS following RR totaling 9.6 months. Notably, in 10 studies with data on subsequent progressions (2+ recurrences), 6 studies reported significant increases in OS with subsequent repeat resection (sRR) compared to those not undergoing sRR.

CONCLUSIONS

Recurrent GBM presents a treatment challenge. There appears to be an OS benefit for RR upon first recurrence as well as sRR. Such findings warrant further investigation of the potential benefits of continued surgical intervention after subsequent progressions of GBM.

Assessment of the efficacy of passive cellular immunotherapy for glioma patients

To evaluate the therapeutic efficacy of passive cellular immunotherapy for glioma, a total of 979 patients were assigned to the meta-analysis. PubMed and the Cochrane Central Register of Controlled Trials were searched initially from February 2018 and updated in April 2019. The overall survival (OS) rates and Karnofsky performance status (KPS) values of patients who underwent passive cellular immunotherapy were compared to those of patients who did not undergo immunotherapy. The proportion of survival rates was also evaluated in one group of clinical trials. Pooled analysis was performed with random- or fixed-effects models. Clinical trials of lymphokine-activated killer cells, cytotoxic T lymphocytes, autologous tumor-specific T lymphocytes, chimeric antigen receptor T cells, cytokine-induced killer cells, cytomegalovirus-specific T cells, and natural killer cell therapies were selected. Results showed that treatment of glioma with passive cellular immunotherapy was associated with a significantly improved 0.5-year OS (p = 0.003) as well as improved 1-, 1.5-, and 3-year OS (p ≤ 0.05). A meta-analysis of 206 patients in one group of clinical trials with 12-month follow-up showed that the overall pooled survival rate was 37.9% (p = 0.003). Analysis of KPS values demonstrated favorable results for the immunotherapy arm (p < 0.001). Thus, the present meta-analysis showed that passive cellular immunotherapy prolongs survival and improves quality of life for glioma patients, suggesting that it has some clinical benefits.

[Repetitive resection and intrasurgery radiation therapy of brain malignant gliomas: history of question and modern state of problem]

Numerous studies have shown that the degree of primary resection of malignant gliomas of the brain (MG) directly correlates with rates of relapse-free and overall patient survival. Currently, there is no unequivocal opinion regarding the indications and effectiveness of repeated resection in relapse of MG after combined treatment. Surgical intervention, taking into account the pathomorphological features of these tumors, is not healing and should be supplemented with certain methods of adjuvant treatment. The article reviews and analyzes publications devoted to repeated resection and various methods of intraoperative radiation therapy in the treatment of MG. Based on the analysis, the authors of the article came to the conclusion that it is advisable to start their own research on the use of intraoperative balloon brachytherapy in the treatment of recurrent MG based on modern technological solutions.

Repeat Resection and Intraoperative Radiotherapy for Malignant Gliomas of the Brain: A History and Review of Current Techniques

The degree of primary resection of malignant brain gliomas (MBGs) has correlated positively with progression-free and overall survival. The indications for surgery and reoperation in MBG relapse remain controversial. Surgery will not be curative and should be followed by adjuvant treatment. We reviewed the reported studies with respect to repeat resection and the various methods of intraoperative radiotherapy for MBGs from the initial experience with high-energy linear accelerators in Japan to modern, integrated brachytherapy solutions using solid and balloon applicators. Because of the findings from our review, we have begun to research into the use of intraoperative balloon brachytherapy for recurrent MBGs.

Upregulation of the NLRC4 inflammasome contributes to poor prognosis in glioma patients

Inflammation in tumor microenvironments is implicated in the pathogenesis of tumor development. In particular, inflammasomes, which modulate innate immune functions, are linked to tumor growth and anticancer responses. However, the role of the NLRC4 inflammasome in gliomas remains unclear. Here, we investigated whether the upregulation of the NLRC4 inflammasome is associated with the clinical prognosis of gliomas. We analyzed the protein expression and localization of NLRC4 in glioma tissues from 11 patients by immunohistochemistry. We examined the interaction between the expression of NLRC4 and clinical prognosis via a Kaplan-Meier survival analysis. The level of NLRC4 protein was increased in brain tissues, specifically, in astrocytes, from glioma patients. NLRC4 expression was associated with a poor prognosis in glioma patients, and the upregulation of NLRC4 in astrocytomas was associated with poor survival. Furthermore, hierarchical clustering of data from the Cancer Genome Atlas dataset showed that NLRC4 was highly expressed in gliomas relative to that in a normal healthy group. Our results suggest that the upregulation of the NLRC4 inflammasome contributes to a poor prognosis for gliomas and presents a potential therapeutic target and diagnostic marker.

Survival Benefit of Maximal Resection for Glioblastoma Reoperation in the Temozolomide Era: A Meta-Analysis

BACKGROUND

Although reoperation likely confers survival benefit for glioblastoma, whether the extent of resection (EOR) of the reoperation affects survival outcome has yet to be thoroughly evaluated in the current temozolomide (TMZ) era. The aim of this meta-analysis was to pool the current literature and evaluate the prognostic significance of reoperation EOR for glioblastoma recurrence in the current TMZ era.

METHODS

Searches of 7 electronic databases from inception to January 2019 were conducted following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. There were 1203 articles identified for screening. Prognostic hazard ratios (HRs) for overall survival (OS) derived from multivariate regression analysis were analyzed using meta-analysis of proportions.

RESULTS

Nine individual studies satisfied all selection criteria, describing survival in 1507 patients with glioblastoma, including 1335 reoperations for recurrence (89%). When studies incorporated the EOR of index surgery into their analysis, maximal resection at reoperation was significantly prognostic for longer OS (HR, 0.59; 95% confidence interval [CI], 0.43-0.79; I² = 0%; P heterogeneity <0.01). When studies did not incorporate the EOR of index surgery into their analysis, maximal resection remained significantly prognostic for longer OS at reoperation (HR, 0.53; 95% CI, 0.45-0.64; I² = 5.2%; P heterogeneity <0.01). Based on EOR, radiographic gross total resection (GTR) was the most prognostic EOR definition at reoperation (HR, 0.52; 95% CI, 0.44-0.61; I² = 0%; P heterogeneity <0.01).

CONCLUSIONS

In the current TMZ era, when reoperation is feasible for recurrent glioblastoma, maximal safe resection appears to confer a significant OS benefit based on the current literature. This benefit is most pronounced with radiographic GTR, and likely irrespective of EOR at index surgery.

Direct Reprogramming of Glioblastoma Cells into Neurons Using Small Molecules

Glioblastoma multiforme, a type of deadly brain cancer, originates most commonly from astrocytes found in the brain. Current multimodal treatments for glioblastoma minimally increase life expectancy, but significant advancements in prognosis have not been made in the past few decades. Here we investigate cellular reprogramming for inhibiting the aggressive proliferation of glioblastoma cells. Cellular reprogramming converts one differentiated cell type into another type based on the principles of regenerative medicine. In this study, we used cellular reprogramming to investigate whether small molecule mediated reprogramming could convert glioblastoma cells into neurons. We investigated a novel method for reprogramming U87MG human glioblastoma cells into terminally differentiated neurons using a small molecule cocktail consisting of forskolin, ISX9, CHIR99021 I-BET 151, and DAPT. Treating U87MG glioblastoma cells with this cocktail successfully reprogrammed the malignant cells into early neurons over 13 days. The reprogrammed cells displayed morphological and immunofluorescent characteristics associated with neuronal phenotypes. Genetic analysis revealed that the chemical cocktail upregulates the Ngn2, Ascl1, Brn2, and MAP2 genes, resulting in neuronal reprogramming. Furthermore, these cells displayed decreased viability and lacked the ability to form high numbers of tumor-like spheroids. Overall, this study validates the use of a novel small molecule cocktail for reprogramming glioblastoma into nonproliferating neurons.

The effect of tumor removal via craniotomies on preoperative hydrocephalus in adult patients with intracranial tumors

The efficacy of tumor removal via craniotomies on preoperative hydrocephalus (HC) in adult patients with intracranial tumors is largely unknown. Therefore, we sought to evaluate the effect of tumor resection in patients with preoperative HC and identify the incidence and risk factors for postoperative VP shunt dependency. All craniotomies for intracranial tumors at Oslo University Hospital in patients ≥ 18 years old during a 10-year period (2004-2013) were reviewed. Patients with radiologically confirmed HC requiring surgery and subsequent development of shunt dependency were identified by cross-linking our prospectively collected tumor database to surgical procedure codes for hydrocephalus treatment (AAF). Patients with preexisting ventriculoperitoneal (VP) shunts (N = 41) were excluded. From 4774 craniotomies performed on 4204 patients, a total of 373 patients (7.8%) with HC preoperatively were identified. Median age was 54.4 years (range 18.1-83.9 years). None were lost to follow-up. Of these, 10.5% (39/373) required permanent CSF shunting due to persisting postoperative HC. The risk of becoming VP shunt dependent in patients with preexisting HC was 7.0% (26/373) within 30 days and 8.9% (33/373) within 90 days. Only secondary (repeat) surgery was a significant risk factor for VP shunt dependency. In this large, contemporary, single-institution consecutive series, 10.5% of intracranial tumor patients with preoperative HC became shunt-dependent post-craniotomy, yielding a surgical cure rate for HC of 89.5%. To the best of our knowledge, this is the first and largest study regarding postoperative shunt dependency after craniotomies for intracranial tumors, and can serve as benchmark for future studies.

Carboplatin and oral cyclophosphamide combination after temozolomide failure in malignant gliomas

Background

Temozolomide is a novel cytotoxic agent for malignant gliomas. However, treatment failure occurs approximately in half of patients, and the optimal regimen in this setting has yet to be defined. In the present study, we assessed retrospectively the efficacy and toxicity of the combination of carboplatin and oral cyclophosphamide in temozolomide-resistant patients.

Methods

We evaluated the medical records of 30 patients with malignant gliomas. After failure of temozolomide therapy, patients were treated with a combination of carboplatin and oral cyclophosphamide. Treatment consisted of intravenous carboplatin AUC 6 (based on the Calvert Formula) on day 1 and oral cyclophosphamide 75 mg/m2 daily on days 1 to 14, followed by 14 days of rest, with the treatment repeated every 4 weeks.

Results

All patients were evaluated for response and toxicity. The objective response rate was 30%, including 9 partial responses. Median time to disease progression and median overall survival was 7 months and 8 months, respectively. Clinically responsive patients had statistically significant longer progression-free survival and overall survival than unresponsive patients. Hematological side effects were commonly observed toxicities, with neutropenia the most frequent.

Conclusions

Our data suggest that carboplatin and oral cyclophosphamide therapy is a convenient regimen after failure of temozolomide therapy in patients with malignant gliomas because of its activity, feasibility and tolerability. Further prospective studies are needed in this setting.

Outcomes after second surgery for recurrent glioblastoma: a retrospective case-control study

Studies looking at the benefit of surgery at first relapse (second surgery) for recurrent glioblastoma were confounded by including patients with varying grades of glioma, performance status and extent of resection. This case-controlled study aims to remove these confounders to assess the survival impact of second surgery in recurrent glioblastoma. Retrospective data on patients with glioblastoma recurrence at two tertiary Australian hospitals from July 2009 to April 2015 was reviewed. Patients who had surgery at recurrence were matched with those who did not undergo surgery at recurrence, based on the extent of their initial resection and age. Overall survival (OS1 assessed from initial diagnosis and OS2 from the date of recurrence) as well as functional outcomes after resection were analysed. There were 120 patients (60 in each institution); median age at diagnosis was 56 years. Median OS1 was 14 months (95% CI 11.5-15.7) versus 22 months (95% CI 18-25) in patients who did not undergo second surgery and those with surgery at recurrence. OS2 was improved by second surgery (4.7 vs 9.6, HR 0.52, 95% CI 0.38-0.72, P < 0.001), and by chemotherapy, given at recurrence, (HR 0.47, 95% CI 0.24-0.92, P = 0.03). After second surgery, 80% did not require rehabilitation and 61% were independently mobile. Second surgery for recurrent glioblastoma was associated with a survival advantage. Chemotherapy independent of surgery, also improved survival. Functional outcomes were encouraging. More research is required in the era of improved surgical techniques and new antineoplastic therapies.

Indications and Efficacy of Gamma Knife Stereotactic Radiosurgery for Recurrent Glioblastoma: 2 Decades of Institutional Experience

BACKGROUND

The role of stereotactic radiosurgery (SRS) for recurrent glioblastoma and the radionecrosis risk in this setting remain unclear.

OBJECTIVE

To perform a large retrospective study to help inform proper indications, efficacy, and anticipated complications of SRS for recurrent glioblastoma.

METHODS

We retrospectively analyzed patients who underwent Gamma Knife SRS between 1991 and 2013. We used the partitioning deletion/substitution/addition algorithm to identify potential predictor covariate cut points and Kaplan-Meier and proportional hazards modeling to identify factors associated with post-SRS and postdiagnosis survival.

RESULTS

One hundred seventy-four glioblastoma patients (median age, 54.1 years) underwent SRS a median of 8.7 months after initial diagnosis. Seventy-five percent had 1 treatment target (range, 1-6), and median target volume and prescriptions were 7.0 cm 3 (range, 0.3-39.0 cm 3 ) and 16.0 Gy (range, 10-22 Gy), respectively. Median overall survival was 10.6 months after SRS and 19.1 months after diagnosis. Kaplan-Meier and multivariable modeling revealed that younger age at SRS, higher prescription dose, and longer interval between original surgery and SRS are significantly associated with improved post-SRS survival. Forty-six patients (26%) underwent salvage craniotomy after SRS, with 63% showing radionecrosis or mixed tumor/necrosis vs 35% showing purely recurrent tumor. The necrosis/mixed group had lower mean isodose prescription compared with the tumor group (16.2 vs 17.8 Gy; P = .003) and larger mean treatment volume (10.0 vs 5.4 cm 3 ; P = .009).

CONCLUSION

Gamma Knife may benefit a subset of focally recurrent patients, particularly those who are younger with smaller recurrences. Higher prescriptions are associated with improved post-SRS survival and do not seem to have greater risk of symptomatic treatment effect.

Benefit of re-operation and salvage therapies for recurrent glioblastoma multiforme: results from a single institution

The optimal management of recurrent glioblastoma (GBM) has yet to be determined. We aim to assess the benefits of re-operation and salvage therapies (chemotherapy and/or re-irradiation) for recurrent GBM and to identify prognostic factors associated with better survival. All patients who underwent surgery for GBM between January 2005 and December 2012 followed by adjuvant radiotherapy, and who developed GBM recurrence on imaging were included in this retrospective study. Univariate and multivariate analysis was performed using Cox models in order to identify factors associated with overall survival (OS). One hundred and eighty patients treated to a dose of 60 Gy were diagnosed with recurrent GBM. At a median follow-up time of 6.2 months, the median survival (MS) from time of recurrence was 6.6 months. Sixty-nine patients underwent repeat surgery for recurrence based on imaging. To establish the benefits of repeat surgery and salvage therapies, 68 patients who underwent repeat surgery were matched to patients who did not based on extent of initial resection and presence of subventricular zone involvement at recurrence. MS for patients who underwent re-operation was 9.6 months, compared to 5.3 months for patients who did not have repeat surgery (p < 0.0001). Multivariate analysis in the matched pairs confirmed that repeat surgery with the addition of other salvage treatment can significantly affect patient outcome (HR 0.53). Re-operation with additional salvage therapies for recurrent GBM provides survival prolongation at the time of progression.

Policies for reirradiation of recurrent high-grade gliomas: a survey among Italian radiation oncologists

PURPOSE

To assess the contribution of Italian radiation oncologists in the current management of recurrent high-grade gliomas (HGG), focusing on a reirradiation (reRT) approach.

METHODS

In 2015, the Reirradiation and the Central Nervous System Study Groups on behalf of the Italian Association of Radiation Oncology (AIRO) proposed a survey. All Italian radiation oncologists were individually invited to complete an online questionnaire regarding their clinical management of recurrent HGG, focusing on a reRT approach.

RESULTS

A total of 37 of 210 questionnaires were returned (18% of all centers): 16 (43%) from nonacademic hospitals, 14 (38%) from academic hospitals, 5 (13%) from private institutions, and 2 (6%) from hadron therapy centers. The majority of responding centers (59%) treated ≤5 cases per year. Performance status at the time of recurrence, along with a target diameter <5 cm and an interval from primary radiation ≥6 months, were the prevalent predictive factors considered for reRT. Sixty percent of reirradiated patients had already received a salvage therapy, either chemotherapy (40%) or reoperation (20%). The most common approach for reRT was fractionated stereotactic radiotherapy to a mean (photon) dose of 41.6 Gy.

CONCLUSIONS

Although there were wide variations in the clinical practice of reRT across the 37 centers, the core activities were reasonably consistent. These findings provide a basis for encouraging a national collaborative study to develop, implement, and monitor the use of reRT in this challenging clinical setting.

[The phenomenon of long-term survival in glioblastoma patients. Part I: the role of clinical and demographic factors and an IDH1 mutation (R 132 H)]

The median overall survival of glioblastoma patients is about 15 months. Only a small number of patients survive 3 years. The factors of a favorable prognosis for the 'longevity phenomenon' in glioblastoma patients are not fully understood.

OBJECTIVE

to determine the occurrence rate of long-living patients with glioblastomas, identify clinical predictors of a favorable prognosis, and identify the presence and prognostic significance of an IDH1 mutation.

MATERIAL AND METHODS

Among 1494 patients operated on for glioblastoma at the Burdenko Neurosurgical Institute from 2007 to 2012, there were 84 (5.6%) patients who lived more than 3 years after primary surgery. In all the cases, histological specimens were reviewed, and immunohistochemical detection of a mutant IDH1 protein was performed. Overall survival was calculated from the time of first surgery to the date of the last consultation or death, and the recurrence-free period was calculated from the time of first surgery to MRI-verified tumor progression.

RESULTS

The median age of long-living patients with glioblastoma was 45 years (19-65 years). All tumors were located supratentorially. The median Karnofsky performance status score at the time of surgery was 80 (range, 70-100). All patients underwent microsurgical resection of the tumor, followed by chemoradiotherapy. The median recurrence-free period was 36 months (5-98 months). Overall survival of 48, 60, and 84 months was achieved in 23, 15 and 6% of patients, respectively. Among 49 specimens available for the IDH1 analysis, 14 (28.6%) specimens had a mutant protein. There was no significant difference in survival rates in patients with positive and negative results for IDH1 (44.1 vs. 40.8 months; p>0.05).

CONCLUSION

The significance of various factors that may be predictors of a favorable course of the disease is discussed in the literature. This work is the first part of analysis of prognostically significant factors positively affecting overall survival of glioblastoma patients. In our series, the predictors of a favorable prognosis for long-living patients with the verified diagnosis of glioblastoma were as follows: young age, the supratentorial location of the tumor, a high Karnofsky score before surgery, and tumor resection. In our series, we used immunohistochemical tests and found no prognostic significance of the IDH1 gene mutation; further analysis will require application of direct sequencing. We plan to study other morphological and molecular genetic features of tumors, which explain prolonged survival of glioblastoma patients, as well as the role of various types of combined chemoradiation treatment.

Treatment options for recurrent high-grade gliomas

High-grade gliomas are aggressive brain tumors encompassing Grade III and IV classifications. Of these, glioblastoma (GB) is the most malignant with a high rate of recurrence after initial resection. Although standard treatment does exist for newly diagnosed GBs, therapeutic strategies for recurrent GB are less solidified. However, mounting evidence describes the role of re-resection, bevacizumab, chemotherapy, targeted molecular therapies, immunotherapeutic approaches and radiotherapy in recurrent GB management. This review article provides analysis of the aforementioned therapies, through assessing their effect on overall survival. Because GB tumor heterogeneity is prevalent there is a constant need to investigate therapies targeting recurrence. Studies evaluating both therapeutic targets and strategies for high-grade gliomas are and will remain invaluable.

Role of surgical resection in recurrent glioblastoma: prognostic factors and outcome evaluation in an observational study

The role of surgical resection in progressive or recurrent glioblastoma multiforme (GBM) lack of high level of evidence. The aim of this evaluation was to assess the role of surgical resection in relapsing GBM, in relation to the extent of surgical resection (EOR) and the amount of residual tumor volume (RTV). Among patients treated for newly diagnosed GBM between September 2008-December 2014, 64 patients with recurrent GBM were included in this retrospective evaluation. All patients underwent surgical resection followed by adjuvant treatments, chemotherapy and/or radiotherapy Results were evaluated in terms of local control (LC) rate, progression free survival (PFS) and patients overall survival (OS). Gross total resection (GTR) (>90%) was achieved in 48 (75%) patients and subtotal resection (STR) in 16 (25%). RTV was 0 in 40 (62.5%) patients and >0 in 24 (37.5%). No severe postoperative morbidity occurred. The median LC time was 6.0 ± 0.1 months (95% CI 5.29-8.55), with a 1 and 2 years LC rate of 29.4 ± 6.9%. The median PFS time was 6.8 ± 0.8 months, with a 1 year PFS rate of 27.2 ± 7.2% (95% CI 14.2-41.9). The median OS time was 10.3 ± 0.5 months (95% CI 7.6-10.4) with a 1 and 2 years OS rate of 22.5 ± 6.7% (95% CI 10.9-36.6). On univariate analysis EOR and RTV were recorded as conditioning LC and survival. These data was confirmed also in multivariate analysis only for RTV (p < 0.01). Recurrent GBM can take advantage of repeated surgery in selected patients with younger age and good clinical status. The entity of surgical resection was confirmed as conditioning survival.

Re-do Craniotomy for Recurrent Grade IV Glioblastomas: Impact and Outcomes from the National Neuroscience Institute Singapore

AIM

We hypothesize that re-do craniotomy for recurrent grade IV glioblastomas improves survival while preserving outcome in selected patients.

METHODS

A retrospective analysis was conducted of 141 patients, from a prospectively collected database from 2004-2014, with grade IV glioblastomas who underwent craniotomy and excision. Sixty-five patients were included in our analysis. Twenty patients underwent re-do craniotomy at recurrence and were compared with 45 patients who received nonsurgical therapy for recurrences. Primary end point was overall survival from time of diagnosis. Demographic and disease factors were analyzed using Cox regression analysis for significance.

RESULTS

The median survival for those with re-do craniotomy was 25.4 months compared with 11.6 months (P < 0.001) in the group that underwent nonsurgical therapy. The mean age for this group was 53.5 years. This group had a higher postsurgical/treatment median Karnofsky performance scale (KPS) of 80 compared with 60 (P < 0.001) showing better functional outcome. A Cox regression analysis of factors determined that age, KPS at recurrence, extent of resection at initial surgery and re-do craniotomy were significant for positive outcomes.

CONCLUSION

Our results show that in a select group of patients with recurrent grade IV glioblastomas, repeated excision, aiming for gross total resection where safely possible, has significant survival benefit without severely compromising functionality and should be considered.

Recurrent glioblastoma: Current patterns of care in an Australian population

This retrospective population-based survey examined current patterns of care for patients with recurrent glioblastoma (rGBM) who had previously undergone surgery and post-operative therapy at original diagnosis. The patients were identified from the Victorian Cancer Registry (VCR) from 2006 to 2008. Patient demographics, tumour characteristics and oncological management were extracted using a standardised survey by the treating clinicians/VCR staff and results analysed by the VCR. Kaplan-Meier estimates of overall survival (OS) at diagnosis and progression were calculated. A total of 95 patients (48%) received treatment for first recurrence; craniotomy and post-operative treatment (38), craniotomy only (34) and non-surgical treatment (23). Patients receiving treatment at first progression had a higher median OS than those who did not (7 versus 3 months, p<0.0001). All patients progressed after treatment for first progression with 43 patients (45%) receiving treatment at second progression. To our knowledge this is the first population-based pattern of care survey of treatment for rGBM in an era where post-operative "Stupp" chemo-radiation is standard. First and second line therapy for rGBM is common and associated with significant benefit. Treatment generally includes re-resection and/or systemic therapy.

Recurrent Glioblastoma: Where we stand

Current first-line treatment regimens combine surgical resection and chemoradiation for Glioblastoma that provides a slight increase in overall survival. Age on its own should not be used as an exclusion criterion of glioblastoma multiforme (GBM) treatment, but performance should be factored heavily into the decision-making process for treatment planning. Despite aggressive initial treatment, most patients develop recurrent diseases which can be treated with re-resection, systemic treatment with targeted agents or cytotoxic chemotherapy, reirradiation, or radiosurgery. Research into novel therapies is investigating alternative temozolomide regimens, convection-enhanced delivery, immunotherapy, gene therapy, antiangiogenic agents, poly ADP ribose polymerase inhibitors, or cancer stem cell signaling pathways. Given the aggressive and resilient nature of GBM, continued efforts to better understand GBM pathophysiology are required to discover novel targets for future therapy.

Biopsy vs. extensive resection for first recurrence of glioblastoma: is a prospective clinical trial warranted?

BACKGROUND

Glioblastoma is an aggressive and almost universally fatal tumor. The prognosis at the time of recurrence has generally been poor, with overall survival typically in the range of 4-40 weeks. The merits of surgical resection (vs. open biopsy, to confirm recurrence via histology) in addition to conventional adjuvant chemotherapy have been the subject of longstanding debate. We wondered whether it would possible to conduct a trial at our institution to settle this question definitively with Class I evidence.

RESULTS

Initially, we had hoped to conduct a randomized, unblinded prospective clinical trial. However on closer inspection it appeared that such an undertaking would pose significant practical challenges. Thus we present our protocol in draft form. In keeping with recommended outcomes for these tumors, the primary endpoint would be median progression free survival. Secondary end points would be: median overall survival (mOS, from time of recurrence) and change in Karnofsky Performance Status over time. Patients would be eligible at the time of first recurrence if they had received conventional treatment until that point and at least 1 month had elapsed since the time of radiation. All patients would be considered potentially eligible for enrollment (unless the decision regarding resection was already clear-cut in view of other factors). Using Cox's proportional hazards model, we estimate that at least 456 patients would be necessary to demonstrate an increase in the hazard ratio to 1.3 for those undergoing biopsy alone. This magnitude of benefit is estimated based on a review of retrospective studies.

DISCUSSION

If restricted to our Institution alone, which sees approximately 100-150 new cases of glioblastoma each year, a trial of this nature would be likely to take around 10 years. Furthermore, there may be significant reluctance on the part of patients and physicians to participate. There is also the opportunity cost of excluding patients from other trials to consider. We recognize that the estimate of the magnitude of effect may be conservative. As things stand, we feel that multi-institutional collaboration would almost certainly be required for an undertaking of this kind.

Clinical benefit from resection of recurrent glioblastomas: results of a multicenter study including 503 patients with recurrent glioblastomas undergoing surgical resection

BACKGROUND

While standards for the treatment of newly diagnosed glioblastomas exist, therapeutic regimens for tumor recurrence remain mostly individualized. The role of a surgical resection of recurrent glioblastomas remains largely unclear at present. This study aimed to assess the effect of repeated resection of recurrent glioblastomas on patient survival.

METHODS

In a multicenter retrospective-design study, patients with primary glioblastomas undergoing repeat resections for recurrent tumors were evaluated for factors affecting survival. Age, Karnofsky performance status (KPS), extent of resection (EOR), tumor location, and complications were assessed.

RESULTS

Five hundred and three patients (initially diagnosed between 2006 and 2010) undergoing resections for recurrent glioblastoma at 20 institutions were included in the study. The patients' median overall survival after initial diagnosis was 25.0 months and 11.9 months after first re-resection. The following parameters were found to influence survival significantly after first re-resection: preoperative and postoperative KPS, EOR of first re-resection, and chemotherapy after first re-resection. The rate of permanent new deficits after first re-resection was 8%.

CONCLUSION

The present study supports the view that surgical resections of recurrent glioblastomas may help to prolong patient survival at an acceptable complication rate.

Stereotactic laser ablation of high-grade gliomas

Evolving research has demonstrated that surgical cytoreduction of a high-grade glial neoplasm is an important factor in improving the prognosis of these difficult tumors. Recent advances in intraoperative imaging have spurred the use of stereotactic laser ablation (laser interstitial thermal therapy [LITT]) for intracranial lesions. Among other targets, laser ablation has been used in the focal treatment of high-grade gliomas (HGGs). The revived application of laser ablation for gliomas parallels major advancements in intraoperative adjuvants and groundbreaking molecular advances in neuro-oncology. The authors review the research on stereotactic LITT for the treatment of HGGs and provide a potential management algorithm for HGGs that incorporates LITT in clinical practice.

[Glioblastoma metastases: a literature review and a description of six clinical observations]

INTRODUCTION

since the 1990s, the literature has described cases of glioblastoma metastases with the development of foci located at a distance from the primary tumor. However, the pathogenesis of this process remains unclear until the end. This focus is believed to result, on the one hand, from tumor metastasis from the primary site and, on the other hand, from multifocal growth. This article presents a literature review and a description of clinical observations of patients with glioblastoma metastases.

MATERIAL AND METHODS

The study included 6 patients (1 female and 5 males) with brain glioblastomas who received treatment at the Burdenko Neurosurgical Institute (5 patients) and the Department of Neurosurgery of the Research Center of Neurology (1 patient) in the period from 2010 to 2014. Neurophysiological control was used if the tumor was localized near the eloquent cortical areas and pathways; 4 of 6 patients were operated on using the methods of intraoperative fluorescence diagnosis (5-ALA agent--Alasens).

RESULTS

Four patients had metastases within one hemisphere, two had metastases in the contralateral hemisphere in the period of 5 to 18 months after the first operation. The primary tumor site was located near the ventricular system in two patients. In one patient, the lateral ventricle was opened during the first operation. In another patient, the prepontine cistern was opened during the first operation. In two patients, the primary tumor site was located at a distance from the lateral ventricles, however, the tumor was located near them during recurrence. Based on metabolic navigation, fluorescence of the tumor was observed in the four patients during both the first and repeated operations.

CONCLUSIONS

The close relationship between primary glioblastomas and metastases and the cerebrospinal fluid circulation pathways may confirm the fact of dissemination of tumor cells with cerebrospinal fluid flow. In our opinion, there should be an increased suspicion of the possibility for metastases of glioblastomas that are closely associated with the cerebrospinal fluid circulation pathways. Metabolic navigation with 5-ALA is effective both during primary surgery in patients with glioblastomas and during resection of glioblastoma metastases.

Recurrent malignant gliomas

In almost all patients, malignant glioma recurs following initial treatment with maximal safe resection, conformal radiotherapy, and temozolomide. This review describes the many options for treatment of recurrent malignant gliomas, including reoperation, alternating electric field therapy, chemotherapy, stereotactic radiotherapy or radiosurgery, or some combination of these modalities, presenting the evidence for each approach. No standard of care has been established, though the antiangiogenic agent, bevacizumab; stereotactic radiotherapy or radiosurgery; and, perhaps, combined treatment with these 2 modalities appear to offer modest benefits over other approaches. Clearly, randomized trials of these options would be advantageous, and novel, more efficacious approaches are urgently needed.

Salvage Fractionated Stereotactic Radiotherapy with or without Chemotherapy and Immunotherapy for Recurrent Glioblastoma Multiforme: A Single Institution Experience

BACKGROUND

The current standard of care for salvage treatment of glioblastoma multiforme (GBM) is gross total resection and adjuvant chemoradiation for operable patients. Limited evidence exists to suggest that any particular treatment modality improves survival for recurrent GBM, especially if inoperable. We report our experience with fractionated stereotactic radiotherapy (fSRT) with and without chemo/immunotherapy, identifying prognostic factors associated with prolonged survival.

METHODS

From 2007 to 2014, 19 patients between 29 and 78 years old (median 55) with recurrent GBM following resection and chemoradiation for their initial tumor, received 18-35 Gy (median 25) in three to five fractions via CyberKnife fSRT. Clinical target volume (CTV) ranged from 0.9 to 152 cc. Sixteen patients received adjuvant systemic therapy with bevacizumab (BEV), temozolomide (TMZ), anti-epidermal growth factor receptor (125)I-mAb 425, or some combination thereof.

RESULTS

The median overall survival (OS) from date of recurrence was 8 months (2.5-61) and 5.3 months (0.6-58) from the end of fSRT. The OS at 6 and 12 months was 47 and 32%, respectively. Three of 19 patients were alive at the time of this review at 20, 49, and 58 months from completion of fSRT. Hazard ratios for survival indicated that patients with a frontal lobe tumor, adjuvant treatment with either BEV or TMZ, time to first recurrence >16 months, CTV <36 cc, recursive partitioning analysis <5, and Eastern Cooperative Oncology Group performance status <2 were all associated with improved survival (P < 0.05). There was no evidence of radionecrosis for any patient.

CONCLUSION

Radiation Therapy Oncology Group (RTOG) 1205 will establish the role of re-irradiation for recurrent GBM, however our study suggests that CyberKnife with chemotherapy can be safely delivered, and is most effective in patients with smaller frontal lobe tumors, good performance status, or long interval from diagnosis.

Efficacy of Surgery and Further Treatment of Progressive Glioblastoma

BACKGROUND

Treatment options for patients with glioblastoma at progression have remained controversial, and selection criteria for the appropriate type of intervention remain poorly defined. The objectives were to determine which factors favor the decision for second surgery and which factors are associated with overall survival (OS) and to evaluate the National Institutes of Health (NIH) recurrent glioblastoma scale. The scale includes tumor involvement of eloquent brain regions, functional status, and tumor volume.

METHODS

A retrospective single-center analysis of patients with newly diagnosed glioblastoma undergoing initial surgery between January 2007 and December 2011 was performed. Patients were separated into two groups: those with versus those without second resection surgery at disease progression. OS was compared using the multiple logistic regression model, Cox proportional hazard regression, and Kaplan-Meier survival analysis.

RESULTS

The data of 98 patients were statistically analyzed. Among the patients, 58 had initial surgery only (age 61.27 years; median OS [mOS] 14.81 months) and 40 underwent second surgery at disease progression (age 55 years; mOS 18.86 months). Age was the only predictor for repeated surgery (P = 0.012; odds ratio 0.94). At the time of tumor progression, administration of alkylating chemotherapy (P = 0.004; hazard ratio [HR] 0.24) or bevacizumab (P = 0.001; HR 0.23) was associated with longer OS. Reoperation was associated with a lower HR (P = 0.134; HR 0.66). The NIH recurrent glioblastoma scale showed statistically significant improvement of prognosis prediction with the addition of age.

CONCLUSIONS

Surgery of progressive glioblastoma and postoperative treatment at the time of progression is associated with improved OS in some patients. The addition of age may improve survival prediction of the NIH recurrent glioblastoma scale.

Outcome of radiosurgery for recurrent malignant gliomas: assessment of treatment response using relative cerebral blood volume

Gamma knife radiosurgery (GKS) is efficacious for treating recurrent malignant gliomas as a salvage treatment. However, contrast enhancement alone on MR imaging remains difficult to determine the treatment response following GKS. The purpose of this study was to evaluate the radiosurgical effect for recurrent malignant gliomas and to clarify if relative cerebral blood volume (rCBV) derived from dynamic susceptibility-weighted contrast-enhanced (DSC) perfusion MR imaging could represent the treatment response. Between March 2006 and December 2008, 38 patients underwent GKS for recurrent malignant gliomas. Before and after GKS, DSC perfusion MR imaging datasets were retrospectively reprocessed and regions of interest were drawn around the contrast-enhancing region targeted with GKS. DSC-perfusion MR scans were assessed at a regular interval of two months. Following GKS for the recurrent lesions, MR images showed response (stable disease or partial response) in 26 of 38 patients (68.4 %) at post-GKS 2 months and 18 of 38 patients (47.3 %) at post-GKS 4 months. Initial mean rCBV value was 2.552 (0.586-6.178) at the pre-GKS MRI. In the response group, mean rCBV value was significantly decreased (P < 0.05) at the follow up of 2 and 4 months. However, in the treatment-failure group, mean rCBV value had no significant change. We suggest that GKS is an alternative treatment choice for the recurrent glioma. DSC-perfusion MR images are helpful to predict the treatment response after GKS.

Reoperation for Recurrent High-Grade Glioma

Optimal treatment for recurrent high-grade glioma continues to evolve. Currently, however, there is no consensus in the literature on the role of reoperation in the management of these patients. In this analysis, we reviewed the literature to examine the role of reoperation in patients with World Health Organization grade III or IV recurrent gliomas, focusing on how reoperation affects outcome, perioperative complications, and quality of life. An extensive literature review was performed through the use of the PubMed and Ovid Medline databases for January 1980 through August 2013. A total 31 studies were included in the final analysis. Of the 31 studies with significant data from single or multiple institutions, 29 demonstrated a survival benefit or improved functional status after reoperation for recurrent high-grade glioma. Indications for reoperation included new focal neurological deficits, tumor mass effect, signs of elevated intracranial pressure, headaches, increased seizure frequency, and radiographic evidence of tumor progression. Age was not a contraindication to reoperation. Time interval of at least 6 months between operations and favorable performance status (Karnofsky Performance Status score ≥70) were important predictors of benefit from reoperation. Extent of resection at reoperation improved survival, even in patients with subtotal resection at initial operation. Careful patient selection such as avoiding those individuals with poor performance status and bevacizumab within 4 weeks of surgery is important. Although limited to retrospective analysis and patient selection bias, mounting evidence suggests a survival benefit in patients receiving a reoperation at the time of high-grade glioma recurrence.

The role of cytoreductive surgery in the management of progressive glioblastoma : a systematic review and evidence-based clinical practice guideline

QUESTION

Should patients with previously diagnosed malignant glioma who are suspected of experiencing progression of the neoplasm process undergo repeat open surgical resection?

TARGET POPULATION

These recommendations apply to adults with previously diagnosed malignant glioma who are suspected of experiencing progression of the neoplastic process and are amenable to surgical resection.

RECOMMENDATIONS LEVEL II

Repeat cytoreductive surgery is recommended in symptomatic patients with locally recurrent or progressive malignant glioma. The median survival in these patient diagnosed with glioblastoma is expected to range from 6 to 17 months following a second procedure. It is recommended that the following preoperative factors be considered when evaluating a patient for repeat operation: location of recurrence in eloquent/critical brain regions, Karnofsky Performance Status and tumor volume.

Factors impacting survival following second surgery in patients with glioblastoma in the temozolomide treatment era, incorporating neutrophil/lymphocyte ratio and time to first progression

Patients with progressive glioblastoma (GBM) have a poor prognosis. Neutrophil/lymphocyte ratio (NLR), a host inflammatory marker, is prognostic in several solid tumors. The prognostic impact of either NLR, or time from first surgery for GBM to first progression (TTP), in patients undergoing second surgery, has not been assessed. Patients undergoing second surgery for GBM were retrospectively reviewed. Primary outcome was overall survival (OS) and Cox proportional hazard models were used to assess the prognostic value of baseline characteristics including TTP and NLR. Univariable and multivariable analysis (MVA) of OS from second surgery were performed using accelerated failure time Weibull model. Of 584 patients with GBM, 107 (18 %) underwent second surgery between 01/04 and 12/11. Patients who underwent second surgery had longer OS versus those having primary surgery alone; 20.9 versus 9.9 months (P < 0.001). Median OS from second surgery in patients with NLR ≤ 4 versus NLR > 4 was 9.7 versus 5.9 months (log rank P = 0.02). The NLR retained its prognostic significance for survival on MVA (time ratio [TR] 1.65, 95 % confidence interval [CI] 1.15-2.35, P < 0.01). No chemotherapy post second surgery (TR 0.23, 95 % CI 0.16-0.33, P < 0.001) portended worse survival. In patients undergoing second surgery, when TTP was ≤ 12 months, 12-24 months, or >24 months, median OS from second surgery was 7.2, 7.0 and 6.3 months, respectively (P = 0.6). A NLR > 4 prior to second surgery is a poor prognostic factor in GBM and later progression is associated with longer survival in patients but not in longer survival after second surgery.

Surgical management of high-grade gliomas

High-grade gliomas, in particular anaplastic astrocytoma and glioblastoma multiforme, represent two of the most devastating forms of brain cancer. In spite of the poor prognosis, new treatments and emerging therapies are making an impact on this disease. This review discusses the role of the surgical management of high-grade gliomas and provides an overview of the currently available therapies which depend on surgical intervention. At the same time, cutting-edge clinical trials for patients with malignant brain tumors are reviewed to provide further insights into potential future therapies.

The association of subventricular zone involvement at recurrence with survival after repeat surgery in patients with recurrent glioblastoma

Surgical resection is identified as an important prognostic factor for survival in patients undergoing initial resection of glioblastoma (GBM). However, in patients with tumor recurrence, the benefits of repeat surgery remain unclear. Recent reports have stated that the association between initial surgery for GBM and subventricular zone (SVZ) influences survival. The current study examined the relationship of SVZ involvement in recurrent GBM to survival time after reoperation. We conducted a retrospective review of 61 consecutive patients who had undergone repeat surgery for recurrent GBM at our institution between 1997 and 2010. Survival after repeat surgery were compared between patients with (n = 29) and without (n = 32) SVZ involvement at recurrence using univariate analysis with known prognostic factors, including sex, age, Karnofsky Performance Status (KPS) score at recurrence, recurrent tumor size, initial SVZ involvement, and adjuvant therapy after repeat surgery, as variables. All 26 SVZ-positive tumors at initial diagnosis recurred as SVZ-positive tumors, while 32 of 35 SVZ-negative tumors at initial diagnosis remained SVZ-negative at recurrence; the remaining three were SVZ-positive at recurrence. Survival after repeat surgery was decreased in patients with recurrent GBM involving the SVZ at recurrence (p = 0.022). No other prognostic factors for survival after repeat surgery were identified in this study. This finding may have prognostic and therapeutic significance.

Second surgery for recurrent glioblastoma: advantages and pitfalls

Deciding upon the therapeutic approach for patients with recurrent glioblastoma is a challenge. Although second surgery may provide effective palliation, it has yet to be established whether it prolongs survival and/or improves quality of life; nor have data been reported in literature to demonstrate that repeat surgery is indicated for patients with recurrence. The few studies investigating this issue are retrospective and have been conducted on small series, and their data sets are not homogeneous. The aim of the present study was, therefore, to analyze predictors of outcome in patients with recurrent glioblastoma and to make a critical of review of data in literature with a view to comparing the effect on outcome of second surgery against well-known prognostic determinants.