A practical scoring system to determine whether to proceed with surgical resection in recurrent glioblastoma

Pathophysiological role of histamine signaling and its implications in glioblastoma

Glioblastoma (GBM), an extremely aggressive and prevalent malignant brain tumor, remains a challenge to treat. Despite a multimodality treatment approach, GBM recurrence remains inevitable, particularly with the emergence of temozolomide (TMZ) resistance and limited treatment options. Surprisingly, previous studies show that a history of allergies, atopy, or asthma is inversely associated with GBM risk. Further, the electronic medical record at the University Hospital of Lausanne showed that the GBM patients taking antihistamine during treatment had better survival. Histamine is an essential neurotransmitter in the brain and plays a significant role in regulating sleep, hormonal balance, and cognitive functions. Elevated levels of histamine and increased histamine receptor expression have been found in different tumors and their microenvironments, including GBM. High histamine 1 receptor (HRH1) expression is inversely related to overall and progression-free survival in GBM patients, further emphasizing the role of histamine in disease progression. This review aims to provide insights into the challenges of GBM treatment, the role of histamine in GBM progression, and the rationale for considering antihistamines as targeted therapy. The review concludes by encouraging further investigation into antihistamine mechanisms and their impact on the tumor microenvironment.

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.

Recurrent Glioblastoma-Molecular Underpinnings and Evolving Treatment Paradigms

Glioblastoma is the most common and lethal central nervous system malignancy with a median survival after progression of only 6-9 months. Major biochemical mechanisms implicated in glioblastoma recurrence include aberrant molecular pathways, a recurrence-inducing tumor microenvironment, and epigenetic modifications. Contemporary standard-of-care (surgery, radiation, chemotherapy, and tumor treating fields) helps to control the primary tumor but rarely prevents relapse. Cytoreductive treatment such as surgery has shown benefits in recurrent glioblastoma; however, its use remains controversial. Several innovative treatments are emerging for recurrent glioblastoma, including checkpoint inhibitors, chimeric antigen receptor T cell therapy, oncolytic virotherapy, nanoparticle delivery, laser interstitial thermal therapy, and photodynamic therapy. This review seeks to provide readers with an overview of (1) recent discoveries in the molecular basis of recurrence; (2) the role of surgery in treating recurrence; and (3) novel treatment paradigms emerging for recurrent glioblastoma.

SEOM-GEINO clinical guidelines for high-grade gliomas of adulthood (2022)

High-grade gliomas (HGG) are the most common primary brain malignancies and account for more than half of all malignant primary brain tumors. The new 2021 WHO classification divides adult HGG into four subtypes: grade 3 oligodendroglioma (1p/19 codeleted, IDH-mutant); grade 3 IDH-mutant astrocytoma; grade 4 IDH-mutant astrocytoma, and grade 4 IDH wild-type glioblastoma (GB). Radiotherapy (RT) and chemotherapy (CTX) are the current standard of care for patients with newly diagnosed HGG. Several clinically relevant molecular markers that assist in diagnosis and prognosis have recently been identified. The treatment for recurrent high-grade gliomas is not well defined and decision-making is usually based on prior strategies, as well as several clinical and radiological factors. Whereas the prognosis for GB is grim (5-year survival rate of 5-10%) outcomes for the other high-grade gliomas are typically better, depending on the molecular features of the tumor. The presence of neurological deficits and seizures can significantly impact quality of life.

Recurrent Glioblastoma: A Review of the Treatment Options

Glioblastoma is a disease with a poor prognosis. Multiple efforts have been made to improve the long-term outcome, but the 5-year survival rate is still 5-10%. Recurrence of the disease is the usual way of progression. In this situation, there is no standard treatment. Different treatment options can be considered. Among them would be reoperation or reirradiation. There are different studies that have assessed the impact on survival and the selection of patients who may benefit most from these strategies. Chemotherapy treatments have also been considered in several studies, mainly with alkylating agents, with data mostly from phase II studies. On the other hand, multiple studies have been carried out with target-directed treatments. Bevacizumab, a monoclonal antibody with anti-angiogenic activity, has demonstrated activity in several studies, and the FDA has approved it for this indication. Several other TKI drugs have been evaluated in this setting, but no clear benefit has been demonstrated. Immunotherapy treatments have been shown to be effective in other types of tumors, and several studies have evaluated their efficacy in this disease, both immune checkpoint inhibitors, oncolytic viruses, and vaccines. This paper reviews data from different studies that have evaluated the efficacy of different forms of relapsed glioblastoma.

Effects of Reoperation Timing on Survival among Recurrent Glioblastoma Patients: A Retrospective Multicentric Descriptive Study

Glioblastoma inevitably recurs, but no standard regimen has been established for treating this recurrent disease. Several reports claim that reoperative surgery can improve survival, but the effects of reoperation timing on survival have rarely been investigated. We, therefore, evaluated the relationship between reoperation timing and survival in recurrent GBM. A consecutive cohort of unselected patients (real-world data) from three neuro-oncology cancer centers was analyzed (a total of 109 patients). All patients underwent initial maximal safe resection followed by treatment according to the Stupp protocol. Those meeting the following criteria during progression were indicated for reoperation and were further analyzed in this study: (1) The tumor volume increased by >20-30% or a tumor was rediscovered after radiological disappearance; (2) The patient's clinical status was satisfactory (KS ≥ 70% and PS WHO ≤ gr. 2); (3) The tumor was localized without multifocality; (4) The minimum expected tumor volume reduction was above 80%. A univariate Cox regression analysis of postsurgical survival (PSS) revealed a statistically significant effect of reoperation on PSS from a threshold of 16 months after the first surgery. Cox regression models that stratified the Karnofsky score with age adjustment confirmed a statistically significant improvement in PSS for time-to-progression (TTP) thresholds of 22 and 24 months. The patient groups exhibiting the first recurrence at 22 and 24 months had better survival rates than those exhibiting earlier recurrences. For the 22-month group, the HR was 0.5 with a 95% CI of (0.27, 0.96) and a p-value of 0.036. For the 24-month group, the HR was 0.5 with a 95% CI of (0.25, 0.96) and a p-value of 0.039. Patients with the longest survival were also the best candidates for repeated surgery. Later recurrence of glioblastoma was associated with higher survival rates after reoperation.

Updates in the Management of Recurrent Glioblastoma Multiforme

BACKGROUND

 Glioblastoma is the most aggressive and diffusely infiltrative primary brain tumor. Recurrence is almost universal even after all primary standard treatments. This article aims to review the literature and update the standard treatment strategies for patients with recurrent glioblastoma.

METHODS

 A systematic search was performed with the phrase "recurrent glioblastoma and management" as a search term in PubMed central, Medline, and Embase databases to identify all the articles published on the subject till December 2020. The review included peer-reviewed original articles, clinical trials, review articles, and keywords in title and abstract.

RESULTS

 Out of 513 articles searched, 73 were included in this review after screening for eligibility. On analyzing the data, most of the studies report a median overall survival (OS) of 5.9 to 11.4 months after re-surgery and 4.7 to 7.6 months without re-surgery. Re-irradiation with stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) result in a median OS of 10.2 months (range: 7.0-12 months) and 9.8 months (ranged: 7.5-11.0 months), respectively. Radiation necrosis was found in 16.6% (range: 0-24.4%) after SRS. Chemotherapeutic agents like nitrosourea (carmustine), bevacizumab, and temozolomide (TMZ) rechallenge result in a median OS in the range of 5.1 to 7.5, 6.5 to 9.2, and 5.1-13.0 months and six months progression free survival (PFS-6) in the range of 13 to 17.5%, 25 to 42.6%, and 23 to 58.3%, respectively. Use of epithelial growth factor receptor (EGFR) inhibitors results in a median OS in the range of 2.0 to 3.0 months and PFS-6 in 13%.

CONCLUSION

 Although recurrent glioblastoma remains a fatal disease with universal mortality, the literature suggests that a subset of patients may benefit from maximal treatment efforts.

Repeat resection for recurrent glioblastoma in the temozolomide era: a real-world multi-centre study

INTRODUCTION

In contrast to standard-of-care treatment of newly diagnosed glioblastoma, there is limited consensus on therapy upon disease progression. The role of resection for recurrent glioblastoma remains unclear. This study aimed to identify factors for overall survival (OS) and post-progression survival (PPS) as well as to validate an existing prediction model.

METHODS

This was a multi-centre retrospective study that reviewed consecutive adult patients from 2006 to 2019 that received a repeat resection for recurrent glioblastoma. The primary endpoint was PPS defined as from the date of second surgery until death.

RESULTS

1032 glioblastoma patients were identified and 190 (18%) underwent resection for recurrence. Patients that had second surgery were more likely to be younger (<70 years) (adjusted OR: 0.3; 95% CI: 0.1-0.6), to have non-eloquent region tumours (aOR: 1.7; 95% CI: 1.1-2.6) and received temozolomide chemoradiotherapy (aOR: 0.2; 95% CI: 0.1-0.4). Resection for recurrent tumour was an independent predictor for OS (aOR: 1.5; 95% CI: 1.3-1.7) (mOS: 16.9 months versus 9.8 months). For patients that previously received temozolomide chemoradiotherapy and subsequent repeat resection (137, 13%), the median PPS was 9.0 months (IQR: 5.0-17.5). Independent PPS predictors for this group were a recurrent tumour volume of >50cc (aOR: 0.6; 95% CI: 0.4-0.9), local recurrence (aOR: 1.7; 95% CI: 1.1-3.3) and 5-ALA fluorescence-guided resection during second surgery (aOR: 1.7; 95% CI: 1.1-2.8). A National Institutes of Health Recurrent Glioblastoma Multiforme Scale score of 0 conferred an mPPS of 10.0 months, a score of 1-2, 9.0 months and a score of 3, 4.0 months (log-rank test, p-value < 0.05).

CONCLUSION

Surgery for recurrent glioblastoma can be beneficial in selected patients and carries an acceptable morbidity rate. The pattern of recurrence influenced PPS and the NIH Recurrent GBM Scale was a reliable prognostication tool.

Effectiveness and safety of tumor-treating fields therapy for glioblastoma: A single-center study in a Chinese cohort

Objective

Tumor-treating fields (TTFields) are a new therapeutic modality for patients with glioblastoma (GBM). However, studies on survival outcomes of TTFields are rarely reported in China. This study aimed to examine the clinical efficacy and safety of TTFields therapy for GBM in China.

Methods

A total of 93 patients with newly diagnosed GBM (ndGBM) and recurrent GBM (rGBM) were included in our study retrospectively. They were divided into two groups based on whether they used TTFields. Progression-free survival (PFS), overall survival (OS), and toxicities were assessed.

Results

Among the patients with ndGBM, there were 13 cases with TTFields and 39 cases with no TTFields. The median PFS was 15.3 [95% confidence interval (CI): 6.5-24.1] months and 10.6 (95% CI: 5.4-15.8) months in the two groups, respectively, with P = 0.041. The median OS was 24.8 (95% CI: 6.8-42.8) months and 18.6 (95% CI: 11.4-25.8) months, respectively, with P = 0.368. Patients with subtotal resection (STR) who used TTFields had a better PFS than those who did not (P = 0.003). Among the patients with rGBM, there were 13 cases with TTFields and 28 cases with no TTFields. The median PFS in the two groups was 8.4 (95% CI: 1.7-15.2) months and 8.0 (95% CI: 5.8-10.2) months in the two groups, respectively, with P = 0.265. The median OS was 10.6 (95% CI: 4.8-16.4) months and 13.3 (95% CI: 11.0-15.6) months, respectively, with P = 0.655. A total of 21 patients (21/26, 80.8%) with TTFields developed dermatological adverse events (dAEs). All the dAEs could be resolved or controlled.

Conclusion

TTFields therapy is a safe and effective treatment for ndGBM, especially in patients with STR. However, it may not improve survival in patients with rGBM.

Survival analysis in high-grade glioma: The role of salvage surgery

OBJECTIVES

This study addresses the survival of consecutive patients with high-grade gliomas (HGG) treated at the same institution over a period of 10 years. We analyse the importance of associated factors and the role of salvage surgery at the time of progression.

METHODS

We retrospectively analysed a series of patients with World Health Organization (WHO) grade III/IV gliomas treated between 2008 and 2017 at Hospital Gregorio Marañón (Madrid, Spain). Clinical, radiological, and anatomical pathology data were obtained from patient clinical histories.

RESULTS

Follow-up was completed in 233 patients with HGG. Mean age was 62.2 years. The median survival time was 15.4 months. Of 133 patients (59.6%) who had undergone surgery at the time of diagnosis, 43 (32.3%) underwent salvage surgery at the time of progression. This subgroup presented longer overall survival and survival after progression. Higher Karnofsky Performance Status score at diagnosis, a greater extent of surgical resection, and initial diagnosis of WHO grade III glioma were also associated with longer survival.

CONCLUSIONS

About one-third of patients with HGG may be eligible for salvage surgery at the time of progression. Salvage surgery in this subgroup of patients was significantly associated with longer survival.

Analyzing the role of reoperation in recurrent glioblastoma: a 15-year retrospective study in a single institution

BACKGROUND

Multiple treatment options at glioblastoma progression exist, including reintervention, reirradiation, additional systemic therapy, and novel strategies. No alternative has been proven to be superior in terms of postprogression survival (PPS). A second surgery has shown conflicting evidence in the literature regarding its prognostic impact, possibly affected by selection bias, and might benefit a sparse subset of patients with recurrent glioblastoma. The present study aims to determine the prognostic influence of salvage procedures in a cohort of patients treated in the same institution over 15 years.

METHODS

Three hundred and fifty patients with confirmed primary glioblastoma diagnosed and treated between 2005 and 2019 were selected. To examine the role of reoperation, we intended to create comparable groups, previously excluding all diagnostic biopsies and patients who were not actively treated after the first surgery or at disease progression. Uni- and multivariate Cox proportional hazards regression models were employed, considering reintervention as a time-fixed or time-dependent covariate. The endpoints of the study were overall survival (OS) and PPS.

RESULTS

At progression, 33 patients received a second surgery and 84 were treated with chemotherapy only. Clinical variables were similar among groups. OS, but not PPS, was superior in the reintervention group. Treatment modality had no impact in our multivariate Cox regression models considering OS or PPS as the endpoint.

CONCLUSIONS

The association of reoperation with improved prognosis in recurrent glioblastoma is unclear and may be influenced by selection bias. Regardless of our selective indications and high gross total resection rates in second procedures, we could not observe a survival advantage.

Congress of neurological surgeons systematic review and evidence-based guidelines update on the role of cytoreductive surgery in the management of progressive glioblastoma in adults

QUESTION

In patients with previously diagnosed glioblastoma who are suspected of experiencing progression, does repeat cytoreductive surgery improve progression free survival or overall survival compared to alternative interventions?

TARGET POPULATION

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

RECOMMENDATION

Level II: Repeat cytoreductive surgery is recommended in progressive glioblastoma patients to improve overall survival.

Optimizing management of the elderly patient with glioblastoma: Survival prediction online tool based on BC Cancer Registry real-world data

BACKGROUND

Glioblastoma (GBM) is associated with fatal outcomes and devastating neurological presentations especially impacting the elderly. Management remains controversial and representation in clinical trials poor. We generated 2 nomograms and a clinical decision making web tool using real-world data.

METHODS

Patients ≥60 years of age with histologically confirmed GBM (ICD-O-3 histology codes 9440/3, 9441/3, and 9442/3) diagnosed 2005-2015 were identified from the BC Cancer Registry (n = 822). Seven hundred and twenty-nine patients for which performance status was captured were included in the analysis. Age, performance and resection status, administration of radiation therapy (RT), and chemotherapy were reviewed. Nomograms predicting 6- and 12-month overall survival (OS) probability were developed using Cox proportional hazards regression internally validated by c-index. A web tool powered by JavaScript was developed to calculate the survival probability.

RESULTS

Median OS was 6.6 months (95% confidence interval [CI] 6-7.2 months). Management involved concurrent chemoradiation (34%), RT alone (42%), and chemo alone (2.3%). Twenty-one percent of patients did not receive treatment beyond surgical intervention. Age, performance status, extent of resection, chemotherapy, and RT administration were all significant independent predictors of OS. Patients <80 years old who received RT had a significant survival advantage, regardless of extent of resection (hazard ratio range from 0.22 to 0.60, CI 0.15-0.95). A nomogram was constructed from all 729 patients (Harrell's Concordance Index = 0.78 [CI 0.71-0.84]) with a second nomogram based on subgroup analysis of the 452 patients who underwent RT (Harrell's Concordance Index = 0.81 [CI 0.70-0.90]). An online calculator based on both nomograms was generated for clinical use.

CONCLUSIONS

Two nomograms and accompanying web tool incorporating commonly captured clinical features were generated based on real-world data to optimize decision making in the clinic.

CyberKnife for Recurrent Malignant Gliomas: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVE

Possible treatment strategies for recurrent malignant gliomas include surgery, chemotherapy, radiotherapy, and combined treatments. Among different reirradiation modalities, the CyberKnife System has shown promising results. We conducted a systematic review of the literature and a meta-analysis to establish the efficacy and safety of CyberKnife treatment for recurrent malignant gliomas.

METHODS

We searched PubMed, MEDLINE, and EMBASE from 2000 to 2021 for studies evaluating the safety and efficacy of CyberKnife treatment for recurrent WHO grade III and grade IV gliomas of the brain. Two independent reviewers selected studies and abstracted data. Missing information was requested from the authors via email correspondence. The primary outcomes were median Overall Survival, median Time To Progression, and median Progression-Free Survival. We performed subgroup analyses regarding WHO grade and chemotherapy. Besides, we analyzed the relationship between median Time To Recurrence and median Overall Survival from CyberKnife treatment. The secondary outcomes were complications, local response, and recurrence. Data were analyzed using random-effects meta-analysis.

RESULTS

Thirteen studies reporting on 398 patients were included. Median Overall Survival from initial diagnosis and CyberKnife treatment was 22.6 months and 8.6 months. Median Time To Progression and median Progression-Free Survival from CyberKnife treatment were 6.7 months and 7.1 months. Median Overall Survival from CyberKnife treatment was 8.4 months for WHO grade IV gliomas, compared to 11 months for WHO grade III gliomas. Median Overall Survival from CyberKnife treatment was 4.4 months for patients who underwent CyberKnife treatment alone, compared to 9.5 months for patients who underwent CyberKnife treatment plus chemotherapy. We did not observe a correlation between median Time To Recurrence and median Overall Survival from CyberKnife. Rates of acute neurological and acute non-neurological side effects were 3.6% and 13%. Rates of corticosteroid dependency and radiation necrosis were 18.8% and 4.3%.

CONCLUSIONS

Reirradiation of recurrent malignant gliomas with the CyberKnife System provides encouraging survival rates. There is a better survival trend for WHO grade III gliomas and for patients who undergo combined treatment with CyberKnife plus chemotherapy. Rates of complications are low. Larger prospective studies are warranted to provide more accurate results.

Clinical Outcome of Cytoreductive Surgery Prior to Bevacizumab for Patients with Recurrent Glioblastoma: A Single-center Retrospective Analysis

Bevacizumab (BEV) is a key anti-angiogenic agent used in the treatment for recurrent glioblastoma multiforme (GBM). The aim of this study was to investigate whether cytoreductive surgery prior to treatment with BEV contributes to prolongation of survival for patients with recurrent GBM. We retrospectively analyzed the treatment outcomes of 124 patients with recurrent GBM who were initially treated with the Stupp protocol between 2006 and 2019. Given that BEV has only been available in Japan since 2013, we grouped the patients into two groups according to the time of first recurrence: the pre-BEV group (N = 51) included patients who had recurrence before BEV approval, and the BEV group (N = 73) included patients with recurrence after BEV approval. The overall survival after first recurrence (OS-R) was analyzed according to the treatment strategy. Among 124 patients, 27 patients (19.4%) received cytoreductive surgery. There were nine cases in the pre-BEV group and 18 cases in the BEV group. Although the mean extent of resection for both groups was almost equal, OS-R was significantly different. The median OS-R was 8.1 m in the pre-BEV group and 16.3 m in the BEV group (P = 0.007). Multivariate analysis revealed that the unavailability of BEV postoperatively (P = 0.03) and decreasing performance status by surgery (P = 0.01) were significant poor prognostic factors for survival after surgery. With the advent of BEV, cytoreductive surgery might provide superior survival benefit at the time of GBM recurrence, especially in cases where surgery can be performed without deteriorating the patient's condition.

An Immune-Related Signature for Predicting the Prognosis of Lower-Grade Gliomas

Background

Lower-grade gliomas (LGGs) have more favorable outcomes than glioblastomas; however, LGGs often progress to process glioblastomas within a few years. Numerous studies have proven that the tumor microenvironment (TME) is correlated with the prognosis of glioma.

Methods

LGG RNA-Sequencing (RNA-seq) data from The Cancer Genome Atlas (TCGA) and the Chinese Glioma Genome Atlas (CGGA) were extracted and then divided into training and testing cohorts, respectively. Immune-related differentially expressed genes (DEGs) were screened to establish a prognostic signature by a multivariate Cox proportional hazards regression model. The immune-related risk score and clinical information, such as age, sex, World Health Organization (WHO) grade, and isocitrate dehydrogenase 1 (IDH1) mutation, were used to independently validate and develop a prognostic nomogram. GO and KEGG pathway analyses to DEGs between immune-related high-risk and low-risk groups were performed.

Results

Sixteen immune-related genes were screened for establishing a prognostic signature. The risk score had a negative correlation with prognosis, with an area under the receiver operating characteristic (ROC) curve of 0.941. The risk score, age, grade, and IDH1 mutation were identified as independent prognostic factors in patients with LGGs. The hazard ratios (HRs) of the high-risk score were 5.247 [95% confidence interval (CI) = 3.060–8.996] in the multivariate analysis. A prognostic nomogram of 1-, 3-, and 5-year survival was established and validated internally and externally. Go and KEGG pathway analyses implied that immune-related biological function and pathways were involved in the TME.

Conclusion

The immune-related prognostic signature and the prognostic nomogram could accurately predict survival.

Local treatment for relapsing glioblastoma: A decision-making tree for choosing between reirradiation and second surgery

In case of circumscribed recurrent glioblastoma (rec-GBM), a second surgery (Re-S) and reirradiation (Re-RT) are local strategies to consider. The aim is to provide an algorithm to use in the daily clinical practice. The first step is to consider the life expectancy in order to establish whether the patient should be a candidate for active treatment. In case of a relatively good life expectancy (>3 months) and a confirmed circumscribed disease(i.e. without multiple lesions that are in different lobes/hemispheres), the next step is the assessment of the prognostic factors for local treatments. Based on the existing prognostic score systems, patients who should be excluded from local treatments may be identified; based on the validated prognostic factors, one or the other local treatment may be preferred. The last point is the estimation of expected toxicity, considering patient-related, tumor-related and treatment-related factors impacting on side effects. Lastly, patients with very good prognostic factors may be considered for receiving a combined treatment.

Does reintervention improve survival in recurrent glioblastoma? Facing a temporal bias in the literature

BACKGROUND

Glioblastoma (GBM) is the most frequent intraaxial malignant brain tumour, in which recurrence management is a frequent and demanding issue. Recently, reintervention has emerged as a useful tool for treatment. However, some new evidence has shown that most of the articles published could have overestimated its effects. We aimed to analyse the effect on survival of reintervention considering it as a time-dependent variable and to compare it with classic statistical analysis.

METHODS

We performed a retrospective study with GBM patients between 2007 and 2017. We compared the overall survival (OS) between reintervention and non-reintervention groups with time-dependent statistical methods (Simon-Makuch and landmarking methods and time-dependent multivariable Cox analysis) and compared them with those obtained with non-dependent time variable analysis.

RESULTS

A total of 183 patients were included in the analysis and 44 of them were reoperated. The standard analysis with Kaplan-Meier and multivariable Cox regression of the cohort showed an OS of 22.2 months (95% CI 12.56-16.06) in the reintervention group and 11.8 months (95% CI 9.87-13.67) in the non-reintervention group (p < .001); and an HR 0.649 (95% CI 0.434-0.97 p = .035) for reintervention, demonstrating an increase in OS. However, time-dependent analysis with the Simon-Makuch test and the landmarking method showed that the relationship was not consistent, as this increase in OS was not significant. Moreover, time-dependent multivariable Cox analysis did not show that reintervention improved OS in our cohort (HR 0.997 95% CI 0.976-1.018 p = 0.75).

CONCLUSIONS

There has been a temporal bias in the literature that has led to an overestimation of the positive effect of reintervention in recurrent GBM. However, reintervention could still be useful in some selected patients, who should be individualized according to prognostic factors related to the patient, biology of the tumour, and characteristics of surgical procedure.

Survival analysis in high-grade glioma: the role of salvage surgery

OBJECTIVES

This study addresses the survival of consecutive patients with high-grade gliomas treated at the same institution over a period of 10 years. We analyse the importance of associated factors and the role of salvage surgery at the time of progression.

METHODS

We retrospectively analysed a series of patients with World Health Organization (WHO) grade III/IV gliomas treated between 2008 and 2017 at Hospital Gregorio Marañón (Madrid, Spain). Clinical, radiological, and anatomical pathology data were obtained from patient clinical histories.

RESULTS

Follow-up was completed in 233 patients with HGG. Mean age was 62.2 years. The median survival time was 15.4 months. Of 133 patients (59.6%) who had undergone surgery at the time of diagnosis, 43 (32.3%) underwent salvage surgery at the time of progression. This subgroup presented longer overall survival and survival after progression. Higher Karnofsky Performance Status score at diagnosis, a greater extent of surgical resection, and initial diagnosis of WHO grade III glioma were also associated with longer survival.

CONCLUSIONS

About one-third of patients with HGG may be eligible for salvage surgery at the time of progression. Salvage surgery in this subgroup of patients was significantly associated with longer survival.

Re-irradiation for recurrent glioblastoma multiforme: a critical comparison of different concepts

PURPOSE

Purpose of this study was to investigate outcome and toxicity of re-irradiation for recurrent primary glioblastoma (rGBM). We evaluated a group of patients with rGBM and identical primary treatment comprising adjuvant radiotherapy (30 × 2 Gy) with concurrent temozolomide (TMZ).

METHODS

In this retrospective study of 46 patients, all received adjuvant or definitive normofractionated radiotherapy to a pretreated area, some with concurrent chemotherapy. Impact of different clinical, histological, or epidemiological factors on survival and radiation toxicity was reviewed.

RESULTS

Of 46 patients, 40 completed the intended therapy. Overall survival (OS) was 20 months (range 6-72 months). Overall survival and progression-free survival after re-irradiation (OS2 and PFS2) were 9.5 and 3.4 months (range 2-40 and 0.7-44 months). Simultaneous systemic therapy improved PFS2 and OS2 (4.3 vs. 2.0, p < 0.001 and 12 vs. 4 months, p = 0.13, respectively). Therapy with TMZ or bevacizumab improved PFS2 vs. nitrosureas (6.6 vs. 2.9, p = 0.03 and 5.1 vs. 2.9 months, p = 0.035, respectively). TMZ also improved PFS2 and OS2 vs. all other systemic therapies (6.6 vs. 4, p < 0.001 and 17 vs. 10 months, p = 0.1). In a subgroup analysis for patients with methylation of the MGMT promoter, doses of >36 Gy as well as TMZ vs. no systemic therapy improved PFS2 (p = 0.045 and p = 0.03, respectively). 27.5% of all patients had no acute toxicity. Three patients with acute and four patients with late grade 3 toxicities were reported.

CONCLUSION

Normofractionated radiotherapy is a feasible option for rGBM with a good toxicity profile. Simultaneously applied systemic therapy was associated with improved outcome. For MGMT promoter-methylated histology, higher radiation doses improved survival.

Treatment Results for Recurrent Glioblastoma and Alteration of Programmed Death-Ligand 1 Expression After Recurrence

OBJECTIVE

This study was designed to analyze the results of recurrent glioblastoma (GBM) treatment, investigate the changes in molecular expression on paired primary and recurrent tumor specimens of GBM, and evaluate the effect of these changes on patient survival.

METHODS

A total of 170 adult patients were diagnosed with recurrent GBM at a single institution between 2005 and 2015. Patients were divided into the reoperation and nonoperation groups. In addition, we evaluated the expression of immunologic markers of 43 paired surgical specimens from the first and second operations.

RESULTS

The median overall survival (OS) after recurrence in the reoperation group was significantly longer than that in the nonoperation group (median, 9.1 months vs. 5.6 months; P = 0.024). The groups differed in characteristics such as age, performance scale, and progression-free survival. In the reoperation group, higher performance scale at recurrence, better extent of resection, and adjuvant treatment were related to longer overall survival. Among 43 paired surgical specimens, programmed death-ligand 1 (PD-L1) was positively expressed in 17 (39.5%) and 6 (13.9%) patients after the first and second operations, respectively. PD-L1 expression after recurrence showed an increase, decrease, and no change in 6 (13.9%), 14 (32.5%), and 23 (53.4%) patients, respectively. Changes in PD-L1 expression after recurrence did not affect survival after recurrence during progression.

CONCLUSIONS

The extent of resection and adjuvant treatment was important for prolonged survival. Reoperation without adjuvant treatment was not effective for prolonged survival. Initial and follow-up PD-L1 expression from both operations did not influence patient survival.

[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.

A machine learning approach to predict early outcomes after pituitary adenoma surgery

OBJECTIVEPituitary adenomas occur in a heterogeneous patient population with diverse perioperative risk factors, endocrinopathies, and other tumor-related comorbidities. This heterogeneity makes predicting postoperative outcomes challenging when using traditional scoring systems. Modern machine learning algorithms can automatically identify the most predictive risk factors and learn complex risk-factor interactions using training data to build a robust predictive model that can generalize to new patient cohorts. The authors sought to build a predictive model using supervised machine learning to accurately predict early outcomes of pituitary adenoma surgery.METHODSA retrospective cohort of 400 consecutive pituitary adenoma patients was used. Patient variables/predictive features were limited to common patient characteristics to improve model implementation. Univariate and multivariate odds ratio analysis was performed to identify individual risk factors for common postoperative complications and to compare risk factors with model predictors. The study population was split into 300 training/validation patients and 100 testing patients to train and evaluate four machine learning models using binary classification accuracy for predicting early outcomes.RESULTSThe study included a total of 400 patients. The mean ± SD patient age was 53.9 ± 16.3 years, 59.8% of patients had nonfunctioning adenomas and 84.7% had macroadenomas, and the mean body mass index (BMI) was 32.6 ± 7.8 (58.0% obesity rate). Multivariate odds ratio analysis demonstrated that age < 40 years was associated with a 2.86 greater odds of postoperative diabetes insipidus and that nonobese patients (BMI < 30) were 2.2 times more likely to develop postoperative hyponatremia. Using broad criteria for a poor early postoperative outcome-major medical and early surgical complications, extended length of stay, emergency department admission, inpatient readmission, and death-31.0% of patients met criteria for a poor early outcome. After model training, a logistic regression model with elastic net (LR-EN) regularization best predicted early postoperative outcomes of pituitary adenoma surgery on the 100-patient testing set-sensitivity 68.0%, specificity 93.3%, overall accuracy 87.0%. The receiver operating characteristic and precision-recall curves for the LR-EN model had areas under the curve of 82.7 and 69.5, respectively. The most important predictive variables were lowest perioperative sodium, age, BMI, highest perioperative sodium, and Cushing's disease.CONCLUSIONSEarly postoperative outcomes of pituitary adenoma surgery can be predicted with 87% accuracy using a machine learning approach. These results provide insight into how predictive modeling using machine learning can be used to improve the perioperative management of pituitary adenoma patients.

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.

Reirradiation of recurrent high-grade glioma and development of prognostic scores for progression and survival

Background

Optimal techniques and patient selection for salvage reirradiation of high-grade glioma (HGG) are unclear. In this study, we identify prognostic factors for freedom from progression (FFP) and overall survival (OS) after reirradiation, risk factors for high-grade toxicity, and validate clinical prognostic scores.

Methods

A total of 116 patients evaluated between 2000 and 2018 received reirradiation for HGG (99 WHO grade IV, 17 WHO grade III). Median time to first progression after initial therapy was 10.6 months. Salvage therapies before reirradiation included surgery (31%) and systemic therapy (41%). Sixty-five patients (56%) received single-fraction stereotactic radiosurgery (SRS) as reirradiation. The median biologically effective dose (BED) was 47.25 Gy, and the median planning target volume (PTV) was 4.8 cc for SRS and 95.0 cc for non-SRS treatments. Systemic therapy was given concurrently to 52% and adjuvantly to 74% of patients.

Results

Median FFP was 4.9 months, and median OS was 11.0 months. Significant multivariable prognostic factors for FFP were performance status, time to initial progression, and BED; for OS they were age, time to initial progression, and PTV volume at recurrence. High-grade toxicity was correlated to PTV size at recurrence. Three-level prognostic scores were generated for FFP and OS, with cross-validated receiver operating characteristic area under the curve (AUC) of 0.640 and 0.687, respectively.

Conclusions

Clinical variables at the time of reirradiation for HGG can be used to prognosticate FFP and OS.

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.

A Meta-Analysis of Survival Outcomes Following Reoperation in Recurrent Glioblastoma: Time to Consider the Timing of Reoperation

Background: Glioblastoma multiforme (GBM) inevitably recurs, but no standard regimen has been established for recurrent patients. Reoperation at recurrence alleviates mass effects, and the survival benefit has been reported in many studies. However, in most studies, the effect of reoperation timing on survival benefit was ignored. The aim of this meta-analysis was to investigate whether reoperation provided similar survival benefits in recurrent GBM patients when it was analyzed as a fixed or time-dependent covariate.

Methods: A systematic literature search of PubMed, EMBASE, and Cochrane databases was performed to identify original articles that evaluated the associations between reoperation and prognosis in recurrent GBM patients.

Results: Twenty-one articles involving 8,630 patients were included. When reoperation was considered as a fixed covariate, it was associated with better overall survival (OS) and post-progression survival (PPS) (OS: HR = 0.66, 95% CI 0.61-0.71, p < 0.001, I² = 0%; PPS: HR = 0.70, 95% CI 0.57–0.88, p < 0.01, I² = 70.2%). However, such a survival benefit was not observed when reoperation was considered as a time-dependent covariate (OS: HR = 2.19, 95% CI 1.47–3.27, p < 0.001; PPS: HR = 0.95, 95% CI 0.82–1.10, p = 0.51, I² = 0%). The estimate bias caused by ignoring the time-dependent nature of reoperation was further demonstrated by the re-analysis of survival data in three included studies.

Conclusions: The timing of reoperation may have an impact on the survival outcome in recurrent GBM patients, and survival benefits of reoperation in recurrent GBM may be overestimated when analyzed as fixed covariates. Proper analysis methodology should be used in future work to confirm the clinical benefits of reoperation.

Repeated craniotomies for intracranial tumors: is the risk increased? Pooled analysis of two prospective, institutional registries of complications and outcomes

Purpose

Deciding whether to re-operate patients with intracranial tumor recurrence or remnant is challenging, as the data on safety of repeated procedures is limited. This study set out to evaluate the risks for morbidity, mortality, and complications after repeated operations, and to compare those to primary operations.

Methods

Retrospective observational two-center study on consecutive patients undergoing microsurgical tumor resection. The data derived from independent, prospective institutional registries. The primary endpoint was morbidity at 3 months (M3), defined as significant decrease on the Karnofsky Performance Scale (KPS). Secondary endpoints were mortality, rate and severity of complications according to the Clavien–Dindo Grade (CDG).

Results

463/2403 (19.3%) were repeated procedures. Morbidity at M3 occurred in n = 290 patients (12.1%). In univariable analysis, patients undergoing repeated surgery were 98% as likely as patients undergoing primary surgery to experience morbidity (OR 0.98, 95% CI 0.72–1.34, p = 0.889). In multivariable analysis adjusted for age, sex, tumor size, histology and posterior fossa location, the relationship remained stable (aOR 1.25, 95% CI 0.90–1.73, p = 0.186). Mortality was n = 10 (0.4%) at discharge and n = 95 (4.0%) at M3, without group differences. At least one complication occurred in n = 855, and the rate (35.5% vs. 35.9%, p = 0.892) and severity (CDG; p = 0.520) was similar after primary and repeated procedures. Results were reproduced in subgroup analyses for meningiomas, gliomas and cerebral metastases.

Conclusions

Repeated surgery for intracranial tumors does not increase the risk of morbidity. Mortality, and both the rate and severity of complications are comparable to primary operations. This information is of value for patient counseling and the informed consent process.

Electronic supplementary material

The online version of this article (10.1007/s11060-018-03058-y) contains supplementary material, which is available to authorized users.

Reoperation for Recurrent Glioblastoma Multiforme

The role of reoperation for glioblastoma multiforme (GBM) recurrence is currently unknown. However, multiple studies have indicated that survival and quality of life are improved with a repeat operation at the time of disease recurrence. Prognosis is likely interdependent on several factors, including age, functional status, initial resection status, disease location, and surgical efficacy. However, there are significant data indicating no survival benefit for reoperation. This comprehensive literature review considering the controversial question of whether to operate for progressive or recurrent GBM seeks to evaluate the current available evidence and report on its conclusions.

Re-irradiation as salvage treatment in recurrent glioblastoma: A comprehensive literature review to provide practical answers to frequently asked questions

The primary aim of this review is to provide practical recommendations in terms of fractionation, dose, constraints and selection criteria to be used in the daily clinical routine. Based on the analysis of the literature reviewed, in order to keep the risk of severe side effects ≤3,5%, patients should be stratified according to the target volume. Thus, patients should be treated with different fractionation and total EQD2 (<12.5 ml: EQD2 < 65 Gy with radiosurgery; >12.5 ml and <35 ml: EQD2 < 50 Gy with hypofractionated stereotactic radiotherapy; >35 ml and <50 ml: EQD2 < 36 Gy with conventionally fractionated radiotherapy). Concurrent approaches with temozolomide or bevacizumab do not seem to improve the outcomes of reirradiation and may lead to a higher risk of toxicity but these findings need to be confirmed in prospective series.

Hypofractionated Re-irradiation after Maximal Surgical Resection for Recurrent Glioblastoma: Therapeutic Adequacy and Its Prognosticators of Survival

PURPOSE

To evaluate the adequacy of retreatment, including hypofractionated re-irradiation (HFReRT), after surgery for recurrent glioblastoma (GBM) and related prognosticators of outcomes.

MATERIALS AND METHODS

From 2011 to 2014, 25 consecutive patients with recurrent (n=17) or secondary (n=7) disease underwent maximal surgery and subsequent HFReRT after meeting the following conditions: 1) confirmation of recurrent or secondary GBM after salvage surgery; 2) Karnofsky performance score (KPS) ≥60; and 3) interval of ≥12 months between initial radiotherapy and HFReRT. HFReRT was delivered using a simultaneous integrated boost technique, with total dose of 45 Gy in 15 fractions to the gross tumor volume (GTV) and 37.5 Gy in 15 fractions to the clinical target volume.

RESULTS

During a median follow-up of 13 months, the median progression-free and overall survival (OS) were 13 and 16 months, respectively. A better KPS (p=0.026), no involvement of the eloquent area at recurrence (p=0.030), and a smaller GTV (p=0.005) were associated with better OS. Additionally, OS differed significantly between risk groups stratified by the National Institutes of Health Recurrent GBM Scale (low-risk vs. high-risk, p=0.025). Radiologically suspected radiation necrosis (RN) was observed in 16 patients (64%) at a median of 9 months after HFReRT, and 8 patients developed grade 3 RN requiring hospitalization.

CONCLUSION

HFReRT after maximal surgery prolonged survival in selected patients with recurrent GBM, especially those with small-sized recurrences in non-eloquent areas and good performance.

Influence of neutrophil-lymphocyte ratio in prognosis of glioblastoma multiforme

Neutrophil-lymphocyte ratio (NLR) is a hematological marker of systemic inflammation and several studies demonstrate an association between a higher NLR and a worse prognosis in many malignancies. However, literature analyzing its prognostic value in glioblastoma multiforme (GBM) is still scarce. We intended to analyze the correlation of NLR with overall survival and progression-free survival in patients with GBM performing a retrospective review of the patients with diagnosis of GBM submitted to a resection surgery in the department of neurosurgery of a tertiary care hospital, between January/2005 and January/2013. 140 patients were included. Mean age at surgery was 62.9 ± 10.0 years and mean age at death was 64.4 ± 9.8 years. Mean overall survival was 19.4 ± 14.3 months and mean progression-free survival was 9.4 ± 8.7 months. There was no correlation of NLR, platelets-lymphocyte ratio (PLR) or absolute counts of neutrophils, lymphocytes and platelets with overall survival in multivariate analysis. However, a preoperative NLR ≤ 5 correlated with a shorter progression-free survival [HR 1.56 (SD 95% 1.04-2.34); p = 0.032]. We performed a subgroup analysis of patients who completed Stupp protocol. In this subgroup of 117 patients, a preoperative NLR > 7 correlated with a shorter overall survival [HR 1.65 (SD 95% 1.07-2.53); p = 0.023]. The results from our total cohort didn't confirm the correlation between a higher NRL and worse survival in GBM. However, in the subgroup analysis of patients who completed Stupp protocol, a higher NLR was an independent prognostic factor to a shorter overall survival, similar to existent literature data about GBM.

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.

Relapsed Glioblastoma: Treatment Strategies for Initial and Subsequent Recurrences

OPINION STATEMENT

At the time of glioblastoma (GBM) recurrence, a sharp analysis of prognostic factors, disease characteristics, response to adjuvant treatment, and clinical conditions should be performed. A prognostic assessment could allow a careful selection between patients that could be proposed to intensified approaches or palliative setting. Participation in clinical trials aims to improve outcome, and should be encouraged due to dismal prognosis of GBM patients after recurrence. Reoperation should be proposed if the tumor is amenable to a complete resection and if prognostic factors suggest that patient could benefit from a second surgery. Second-line chemotherapy should be chosen based on MGMT status, time to disease recurrence, and toxicity profile. If enrollment into a clinical trial is not possible, a nitrosourea-based regimen is the preferred choice, carefully evaluating any previous temozolomide (TMZ)-related toxicity. In MGMT-methylated patients relapsing after TMZ completion, a rechallenge could be proposed. After second progression, the clinical advantage of subsequent lines of chemotherapy still needs to be clarified. However, based on performance status, patients' preference, and disease behavior, a third-line treatment could be considered. Available treatments include nitrosoureas, bevacizumab, or carboplatin plus etoposide. However, more effective therapeutic options are needed.

Loss of Pericytes in Radiation Necrosis after Glioblastoma Treatments

Radiation necrosis (RN) in brain tumor patients is often symptomatic, persistent without immediate resolution, and confused with tumor recurrence. Cerebral vascular pericytes are essential for endothelial function, vascular integrity, and angiogenesis. In this study, we showed that the loss of pericytes is involved in the pathogenesis of RN. From a brain tumor tissue repository, we identified three patients since 2011 with pathologically confirmed RN after the standard treatment for glioblastoma (GBM). The RN and their preradiation GBM tissues were serially processed for Western blotting using cell-type-specific antibodies against endothelial (CD31, active RhoA), pericyte [platelet-derived growth factor receptor-beta (PDGFR-β)], alpha-smooth muscle actin (α-SMA), astrocyte (GFAP), myelin sheath protein (MBP), and microglial markers (Iba1). Normal brain tissues from a brain bank were used as normal controls. The expressions of PDGFR-β and α-SMA were remarkably reduced in the RN, compared to those of GBM. However, the levels of CD31 or RhoA were not different between the two groups, which suggest that there was no change in the number of endothelial cells or their cytoskeletal assembly. The RN tissues showed a decreased ratio of pericyte/endothelial markers and an increased level of Iba1 compared to the GBM and even to the normal brain. The levels of GFAP and MBP were not changed in the RN. In the histopathology, the RN tissues showed a loss of markers (PDGFR-β), whereas the GBM tissues had abundant expression of the markers. The loss of pericytes and vascular smooth muscle cells, and the unsupported endothelial cells might be the cause of the leaky blood-brain barrier and tissue necrosis.

Elderly patients with newly diagnosed glioblastoma: can preoperative imaging descriptors improve the predictive power of a survival model?

The purpose of this study was to identify independent prognostic factors among preoperative imaging features in elderly glioblastoma patients and to evaluate whether these imaging features, in addition to clinical features, could enhance the predictive power of survival models. This retrospective study included 108 patients ≥65 years of age with newly diagnosed glioblastoma. Preoperative clinical features (age and KPS), postoperative clinical features (extent of surgery and postoperative treatment), and preoperative MRI features were assessed. Univariate and multivariate cox proportional hazards regression analyses for overall survival were performed. The integrated area under the receiver operating characteristic curve (iAUC) was calculated to evaluate the added value of imaging features in the survival model. External validation was independently performed with 40 additional patients ≥65 years of age with newly diagnosed glioblastoma. Eloquent area involvement, multifocality, and ependymal involvement on preoperative MRI as well as clinical features including age, preoperative KPS, extent of resection, and postoperative treatment were significantly associated with overall survival on univariate Cox regression. On multivariate analysis, extent of resection and ependymal involvement were independently associated with overall survival and preoperative KPS showed borderline significance. The model with both preoperative clinical and imaging features showed improved prediction of overall survival compared to the model with preoperative clinical features (iAUC, 0.670 vs. 0.600, difference 0.066, 95% CI 0.021-0.121). Analysis of the validation set yielded similar results (iAUC, 0.790 vs. 0.670, difference 0.123, 95% CI 0.021-0.260), externally validating this observation. Preoperative imaging features, including eloquent area involvement, multifocality, and ependymal involvement, in addition to clinical features, can improve the predictive power for overall survival in elderly glioblastoma patients.

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.

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.

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.

Laser interstitial thermal therapy for newly diagnosed and recurrent glioblastoma

OBJECTIVE

Glioblastoma (GBM) is the most common and deadly malignant primary brain tumor. Better surgical therapies are needed for newly diagnosed GBMs that are difficult to resect and for GBMs that recur despite standard therapies. The authors reviewed their institutional experience of using laser interstitial thermal therapy (LITT) for the treatment of newly diagnosed or recurrent GBMs.

METHODS

This study reports on the pre-LITT characteristics and post-LITT outcomes of 8 patients with newly diagnosed GBMs and 13 patients with recurrent GBM who underwent LITT.

RESULTS

Compared with the group with recurrent GBMs, the patients with newly diagnosed GBMs who underwent LITT tended to be older (60.8 vs 48.9 years), harbored larger tumors (22.4 vs 14.6 cm3), and a greater proportion had IDH wild-type GBMs. In the newly diagnosed GBM group, the median progression-free survival and the median survival after the procedure were 2 months and 8 months, respectively, and no patient demonstrated radiographic shrinkage of the tumor on follow-up imaging. In the 13 patients with recurrent GBM, 5 demonstrated a response to LITT, with radiographic shrinkage of the tumor following ablation. The median progression-free survival was 5 months, and the median survival was greater than 7 months.

CONCLUSIONS

In carefully selected patients with recurrent GBM, LITT may be an effective alternative to surgery as a salvage treatment. Its role in the treatment of newly diagnosed unresectable GBMs is not established yet and requires further study.

Complete resection of contrast-enhancing tumor volume is associated with improved survival in recurrent glioblastoma-results from the DIRECTOR trial

BACKGROUND

The role of reoperation for recurrent glioblastoma (GBM) remains unclear. Prospective studies are lacking. Here, we studied the association of clinical outcome with extent of resection upon surgery for recurrent GBM in the patient cohort of DIRECTOR, a prospective randomized multicenter trial comparing 2 dose-intensified temozolomide regimens at recurrence of GBM.

METHODS

We analyzed prospectively collected clinical and imaging data from the DIRECTOR cohort (N = 105). Volumetric analysis was performed on gadolinium contrast-enhanced MRI as well as fluid attenuated inversion recovery/T2 MRI and correlated with PFS after initial progression (PFS2) and post-recurrence survival (PRS). Quality of life was monitored by the EORTC QLQ-C30 and QLQ-BN20 questionnaires at 8-week intervals.

RESULTS

Seventy-one patients received surgery at first recurrence. Prognostic factors, including age, MGMT promoter methylation, and Karnofsky performance score, were balanced between patients with and without reoperation. Outcome in patients with versus without surgery at recurrence was similar for PFS2 (2.0 mo vs 1.9 mo, P = .360) and PRS (11.4 mo vs 9.8 mo, P = .633). Among reoperated patients, post-surgery imaging was available in 59 cases. In these patients, complete resection of contrast-enhancing tumor (N = 40) versus residual detection of contrast enhancement (N = 19) was associated with improved PRS (12.9 mo [95% CI: 11.5-18.2] vs 6.5 mo [95% CI: 3.6-9.9], P < .001) and better quality of life. Incomplete tumor resection was associated with inferior PRS compared with patients who did not undergo surgery (6.5 vs 9.8 mo, P = .052). Quality of life was similar in these 2 groups.

CONCLUSION

Surgery at first recurrence of GBM improves outcome if complete resection of contrast-enhancing tumor is achieved.

Therapeutic options in recurrent glioblastoma--An update

INTRODUCTION

Standards of care are not yet defined in recurrent glioblastoma.

METHODS

We reviewed the literature on clinical trials for recurrent glioblastoma available in PubMed and American Society of Clinical Oncology (ASCO) abstracts until June 2015.

RESULTS

Evidence is limited due to the paucity of randomized controlled studies. Second surgery or re-irradiation are options for selected patients. Alkylating chemotherapy such as nitrosoureas or temozolomide and the vascular endothelial growth factor (VEGF) antibody, bevacizumab, exhibit comparable single agent activity. Phase III data exploring the benefit of combining bevacizumab and lomustine are emerging. Novel approaches in the fields of targeted therapy, immunotherapy, and tumor metabolism are coming forward. Several biomarkers are being explored, but, except for O(6)-methylguanine DNA methyltransferase (MGMT) promoter methylation, none has assumed a role in clinical practice.

CONCLUSION

Proper patient selection, development of predictive biomarkers and randomized controlled studies are required to develop evidence-based concepts for recurrent glioblastoma.

Second surgery for recurrent glioblastoma: A concise overview of the current literature

Optimal treatment for recurrent glioblastoma continues to evolve. Currently, however, there is no consensus in the literature on the role of reoperation in the management of these patients, as several studies provide evidence for a longer overall survival in selected patients with recurrent glioblastoma who underwent second surgery and other studies report a limited impact of second surgery in the clinical course. In this paper, a review of the current literature was performed to analyze the role of reoperation in patients with recurrent glioblastoma and to report the overall survival from diagnosis, progression-free survival and quality of life. Using PubMed and Ovid Medline databases, we performed a review of the literature of the last seven years, finding a total of 28 studies and 2279 patients who underwent second surgery, that were included in the final analysis. The median overall survival from diagnosis and the median survival from second surgery were 18.5 months and 9.7 months, respectively. Extent of resection at reoperation improves overall survival, even in patients with subtotal resection at initial operation. Preoperative performance status and age are important predictors of a longer survival, reason why younger patients with a good preoperative performance status could benefit from reoperation.

Patient outcomes following second surgery for recurrent glioblastoma

BACKGROUND

The most appropriate management of recurrent glioblastoma is still controversial. In particular, the role of surgery at recurrence remains uncertain.

PATIENTS & METHODS

From our Institutional data warehouse we analyzed 270 consecutive patients who received second surgery for recurrent glioblastoma, to assess survival after second surgery, and to evaluate prognostic factors.

RESULTS

Complete resection was found in 128 (47.4%) and partial resection in 142 patients (52.6%). Median survival from second surgery was 11.4 months (95% CI: 10.0-12.7). Multivariate analysis showed that age (p = 0.001), MGMT methylation (p = 0.021) and extent of surgery (p < 0.001) are associated with better survival.

CONCLUSION

A complete resection should be the goal for second resection and younger age and MGMT methylation status might be considered in the selection of patients.

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.