Salvage therapy for recurrent glioblastoma multiforme: a multimodal approach combining fluorescence-guided resurgery, interstitial irradiation, and chemotherapy

Brachytherapy is an effective and safe salvage option for re-irradiation in recurrent glioblastoma (rGBM): A systematic review

PURPOSE

To evaluate the clinical efficacy and toxicity of brachytherapy as a salvage therapy for patients with recurrent glioblastoma (rGBM).

METHODS AND MATERIALS

We searched the PubMed, Embase, and Cochrane libraries from its inception to June 2023, for eligible studies in which patients underwent brachytherapy for rGBM. Outcomes of interest were mOS, mPFS, OS, PFS, and adverse events (AEs). For individual clinical survival outcomes and common AEs, weighted-mean descriptive statistics were calculated as a summary measure using study sample size as the weight. The calculation formula is as follows: weighted-mean = Σwx/Σw (w is the sample size and x is the outcome).

RESULTS

This review included 29 studies with a total of 1202 rGBM patients, including 22 retrospective and 7 prospective studies. The results showed that from the time of brachytherapy, the mOS and mPFS were 6.8 to 24.4 months and 3.7 to 11.7 months. The OS of 6 months, 1 year, 18 months, 2 years, and 3 years after brachytherapy were 58.3 % to 85.2 % (weighted-mean 76.2 %), 26 % to 66 % (weighted-mean 41.9 %), 20 % to 37 % (weighted-mean 27.6 %), 11 % to 23 % (weighted-mean 14.8 %), and 8 % to 15 % (weighted-mean 12.1 %), respectively. The PFS of 6 months and 1 year after brachytherapy were 26.7 % to 86 % (weighted-mean 53.4 %) and 14 % to 81 % (weighted-mean 24.1 %). Most patients with rGBM will experience treatment failure again during the follow-up period, mainly local (10.7 % to 79.4 %) or marginal(3.6 % to 22.2 %) recurrence, followed by distant failure (6.7 % to 57.7 %). Although therapeutic AEs had not been uniformly reported, the overall toxicity rate was considered to be low. The common AEs reported included progressive neurologic deterioration, seizures, CSF leak, brain necrosis, hemorrhage, and infection/meningitis, with a weighted-mean incidence of 1.9 %, 2.4 %, 4.1 %, 5.4 %, 2.1 %, and 3.8 %, respectively.

CONCLUSIONS

The evidence summarized above, albeit mostly level III, suggests that brachytherapy has acceptable safety and good post-treatment clinical efficacy for selected patients with rGBM. Well-designed, high-quality, large-sample randomized controlled and prospective studies are needed to further validate these findings.

Turning on the light for brain tumor surgery: A 5-aminolevulinic acid story

To aid surgeons in more complete and safe resection of brain tumors, adjuvant technologies have been developed to improve visualization of target tissue. Fluorescence-guided surgery relies on the use of fluorophores and specific light wavelengths to better delineate tumor tissue, inflammation, and areas of blood-brain barrier breakdown. 5-aminolevulinic acid (5-ALA), the first fluorophore developed specifically for brain tumors, accumulates within tumor cells, improving visualization of tumors both at the core, and infiltrative margin. Here, we describe the background of how 5-ALA integrated into the modern neurosurgery practice, clinical evidence for the current use of 5-ALA, and future directions for its role in neurosurgical oncology. Maximal safe resection remains the standard of care for most brain tumors. Gross total resection of high-grade gliomas (HGGs) is associated with greater overall survival and progression-free survival (PFS) in comparison to subtotal resection or adjuvant treatment therapies alone.1-3 A major challenge neurosurgeons encounter when resecting infiltrative gliomas is identification of the glioma tumor margin to perform a radical resection while avoiding and preserving eloquent regions of the brain. 5-aminolevulinic acid (5-ALA) remains the only optical-imaging agent approved by the FDA for use in glioma surgery and identification of tumor tissue.4 A multicenter randomized, controlled trial revealed that 5-ALA fluorescence-guided surgery (FGS) almost doubled the extent of tumor resection and also improved 6-month PFS.5 In this review, we will highlight the current evidence for use of 5-ALA FGS in brain tumor surgery, as well as discuss the future directions for its use.

Laser hyperthermia: Past, present, and future

Magnetic resonance imaging-guided laser interstitial thermal therapy (LITT) is an ablative procedure using heat from a laser to provide cytoreduction in tissue. It is a minimally invasive procedure that has been used in intracranial pathologies such as high-grade gliomas, metastatic lesions, epilepsy, and other lesions. While LITT may offer a more acceptable complication profile compared to open surgery, the role of laser therapy for intracranial lesions in current treatment paradigms continues to evolve. This review will focus on the background and application of LITT, the current evidence for its use, and future directions for the technology.

GammaTile: Comprehensive Review of a Novel Radioactive Intraoperative Seed-Loading Device for the Treatment of Brain Tumors

GammaTile is a Food and Drug Administration (FDA)-licensed device consisting of four cesium-131 (Cs-131) radiation-emitting seeds in the collagen tile about the postage stamp size. The tiles are utilized to line the brain cavity immediately after tumor resection. GammaTile therapy is a surgically targeted radiation therapy (STaRT) that helps provide instant, dose-intense treatment after the completion of resection. The objective of this study is to explore the safety and efficacy of GammaTile surgically targeted radiation therapy for brain tumors. This study also reviews the differences between GammaTile surgically targeted radiation therapy (STaRT) and other traditional treatment options for brain tumors. The electronic database searches utilized in this study include PubMed, Google Scholar, and ScienceDirect. A total of 4,150 articles were identified based on the search strategy. Out of these articles, 900 articles were retrieved. A total of 650 articles were excluded for various reasons, thus retrieving 250 citations. We applied the exclusion and inclusion criteria to these retrieved articles by screening their full text and excluding 180 articles. Therefore, 70 citations were retrieved and included in this comprehensive literature review, as outlined in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) diagram. Based on the findings of this study, GammaTile surgically targeted radiation therapy (STaRT) is safe and effective for treating brain tumors. Similarly, the findings have also shown that the efficacy of GammaTile therapy can be enhanced by combining it with other standard-of-care treatment options/external beam radiation therapy (EBRT). Also, the results show that patients diagnosed with recurrent glioblastoma (GBM) exhibit poor median overall survival because of the possibility of the tumor returning. Therefore, combining STaRT with other standard-of-care treatment options/EBRT can improve the patient's overall survival (OS). GammaTile therapy enhances access to care, guarantees 100% compliance, and eliminates patients' need to travel regularly to hospitals for radiation treatments. Its implementation requires collaboration from various specialties, such as radiation oncology, medical physics, and neurosurgery.

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.

Surgical Outcomes of Novel Collagen Tile Cesium Brachytherapy for Recurrent Intracranial Tumors at a Tertiary Referral Center

Treatment for recurrent intracranial neoplasms is often difficult and less standardized. Since its approval by the Food & Drug Administration (FDA), GammaTile^TM (GT, GT Medical Technologies, Tempe, AZ), a novel collagen tile cesium brachytherapy, has been investigated for use in this population. This study presents the initial experience with the use of GT for patients with recurrent intracranial neoplasms at a tertiary referral center. A retrospective analysis of all patients with GT implantation from November 2019 to July 2021 was performed. Information regarding demographics, clinical history, imaging data, prior tumor treatment, dosing, surgical complications, and outcomes was collected. Twelve patients were included in this study. Pathologies included gliomas (five patients), meningiomas (five patients), and metastatic tumors (two patients). The median tumor volume treated was 24 cc (IQR: 21.2 - 31.3 cc), and patients had a median of 7.5 tiles implanted (IQR: 5.4 - 10.3). One patient had a delayed epidural hematoma requiring reoperation, which was unrelated to GT implantation. Median follow-up was seven months (IQR: 3 -10), with the longest follow-up time of 20 months. Two patients have had local disease recurrence and three patients have had systemic progression of their disease. Three patients are deceased with survivals of 2.9, 4.8, and 5.8 months. Collagen tile brachytherapy is a safe and viable option for patients with recurrent intracranial tumors. Our data are consistent with early results seen at other institutions. Long-term data with larger patient populations are required to assess efficacy, safety, and indications for the use of this novel technology.

Re-Irradiation Using Brachytherapy for Recurrent Intracranial Tumors: A Systematic Review and Meta-Analysis of the Literature

Introduction We aim to compare the efficacy and toxicity of re-irradiation using brachytherapy for patients with locally recurrent brain tumors after previous radiation therapy.  Methods We performed a systematic review of the major biomedical databases from 2005 to 2020 for eligible studies where patients were treated with re-irradiation for recurrent same site tumors using brachytherapy. Tumor types included high-grade gliomas (HGG) (World Health Organization (WHO) Grades 3 and 4), meningiomas, and metastases. The outcomes of interest were median overall survival (OS) and progression-free survival (PFS) after re-irradiation, the incidence of radiation necrosis (RN), and other relevant radiation-related adverse events (AE). We used a fixed-effect meta-analysis regression moderation model to compared results of interstitial versus intracavitary therapy, treatment with low-dose-rate (LDR) versus high-dose-rate (HDR) techniques, and outcomes by tumor type. Results The search resulted in a total of 194 articles. A total of 16 articles with 695 patients fulfilled the inclusion criteria and were selected for analysis. For high-grade glioma, meningioma, and brain metastasis the pooled meta-analysis showed mean symptomatic RN rates of 3.3% (standard error (SE) = 0.8%), 17.3% (SE = 5.0%), and 22.4% (SE = 7.0%), respectively, and mean rates of RN requiring surgical intervention of 3.0% (SE = 1.0%), 11.9% (SE = 5.3%), and 10.0% (SE = 7.3%), respectively. The mean symptomatic RN rates in the meta-analysis comparing interstitial versus intracavitary therapy were 3.4% and 4.9%, respectively (p = 0.36), and for the comparison of LDR versus HDR, the rates were 2.6% and 5.7%, respectively (p = 0.046). In comparing the symptomatic RN rates in comparison to HGG versus meningioma, the means were 3.3% and 17.3%, respectively (p = 0.006), and in HGG versus metastatic tumors, the means were 3.3% and 22.4%, respectively (p = 0.007). There was no significant difference in rates of RN requiring surgery in any of these groups. Due to the small number of studies and inconsistent recording of OS and PFS, statistical analysis of these parameters could not be performed. Conclusion Published literature on the same site re-irradiation using brachytherapy for recurrent brain tumors is highly limited, with inconsistent reporting of safety and efficacy outcomes. To overcome these shortcomings, we utilized a structured meta-analysis approach to show that re-irradiation with modern brachytherapy is generally safe in terms of the risks of symptomatic RN. We also found that symptomatic RN rates for brachytherapy are significantly lower in recurrent HGG compared to recurrent meningiomas (p = 0.006) and metastatic tumors (p = 0.007). Re-irradiation with brachytherapy is a feasible option for appropriately selected patients. The availability of Cesium-131 (Cs-131) shows promise in reducing toxicity while achieving excellent local control due to its physical properties, and the recent introduction of a novel surgically targeted radiation therapy device, that makes brachytherapy less technically demanding, may allow for more widespread adoption. Prospective trials with consistent reporting of endpoints are needed to explore whether these advances improve safety and efficacy in patients with recurrent, previously irradiated tumors.

GammaTile®: Surgically targeted radiation therapy for glioblastomas

Glioblastoma is the most common primary malignant neoplasm of the central nervous system in adults. Standard of care is resection followed by chemo-radiation therapy. Despite this aggressive approach, >80% of glioblastomas recur in proximity to the resection cavity. Brachytherapy is an attractive strategy for improving local control. GammaTile^® is a newly US FDA-cleared device which incorporates ¹³¹Cs radiation emitting seeds in a resorbable collagen-based carrier tile for surgically targeted radiation therapy to achieve highly conformal radiation at the time of surgery. Embedding encapsulated ¹³¹Cs radiation emitter seeds in collagen-based tiles significantly lowers the technical barriers associated with traditional brachytherapy. In this review, we highlight the potential of surgically targeted radiation therapy and the currently available data for this novel approach.

Fluorescent Guided Surgery in the Surgical Management of Glioma: The Dawn of a New Era

A growing body of evidence supports the importance of marginal or even supramarginal resection in cases of high- but also of low-grade gliomas [...].

Evolving Strategies to Potentially Further Optimize Surgical Interventions in Brain Cancer

PURPOSE OF REVIEW

Provide an overview, the indications for use, and a synopsis of current literature regarding two evolving neurosurgical interventions-GammaTile therapy (GTT) and laser interstitial thermal therapy (LITT).

RECENT FINDINGS

GTT delivers immediate, uniform, high-dose radiation with avoidance of direct brain-to-seed contact. Innate properties of the novel carrier system and cesium-131 source may explain lower observed rate of radiation-induced necrosis (RIN) and support use in larger and previously irradiated lesions. LITT delivers focal laser energy to cause heat-generated necrosis. Case series suggest use in difficult-to-access lesions and treatment of RIN. Collaboration among subspecialties and remaining up-to-date on evolving technology is critical in developing individualized treatment plans for patients with brain cancer. While patients should be thoroughly counseled that these interventions are not standard of care, in optimal clinical scenarios, GTT and LITT could extend quantity and quality of life for patients with few remaining options. Prospective studies are needed to establish specific treatment parameters.

Established and emerging uses of 5-ALA in the brain: an overview

INTRODUCTION

5-aminolevulinic acid (5-ALA) was approved by the FDA in June 2017 as an intra-operative optical imaging agent for patients with gliomas (suspected World Health Organization Grades III or IV on preoperative imaging) as an adjunct for the visualization of malignant tissue during surgery. 5-ALA fluorescence-guided surgery (FGS) has been in widespread use in Europe and other continents since 2007.

METHODS

We reviewed the data available and summarize the most important known uses of 5-ALA FGS and its potential future applications.

RESULTS/CONCLUSIONS

The technique has been extensively studied, and more than 300 papers have been published on this topic. Visualization of high-grade glioma tissue is robust and reproducible, and can impact the extent of tumor resection and patient outcomes. 5-ALA FGS for other kind of tumors needs further development.

Re-irradiation for recurrent glioblastoma (GBM): a systematic review and meta-analysis

PURPOSE

To determine the efficacy and toxicity of re-irradiation for patients with recurrent GBM.

MATERIALS AND METHODS

We searched various biomedical databases from 1998 to 2018, for eligible studies where patients were treated with re-irradiation for recurrent GBM. Outcomes of interest were 6 and 12-month overall survival (OS-6, OS-12), 6 and 12-month progression free survival (PFS-6, PFS-12) and serious (Grade 3 +) adverse events (AE). We used the random effects model to pool outcomes across studies and compared pre-defined subgroups using interaction test. Methodological quality of each study was assessed using the Newcastle-Ottawa scoring system.

RESULTS

We found 50 eligible non-comparative studies including 2095 patients. Of these, 42% were of good or fair quality. The pooled results were as follows: OS-6 rate 73% (95% confidence interval (CI) 69-77%), OS-12 rate 36% (95% CI 32-40%), PFS-6 rate 43% (95% CI 35-50%), PFS-12 rate 17% (95% CI 13-20%), and Grade 3 + AE rate 7% (95% CI 4-10%). Subgroup analysis showed that prospective studies reported higher toxicity rates, and studies which utilized brachytherapy to have a longer OS-12. Within the external beam radiotherapy group, there was no dose-response [above or below 36 Gy in 2 Gy equivalent doses (EQD2)]. However, a short fractionation regimen (≤ 5 fractions) seemed to provide superior PFS-6.

CONCLUSION

The available evidence, albeit mostly level III, suggests that re-irradiation provides encouraging disease control and survival rates. Toxicity was not uniformly reported, but seemed to be low from the included studies. Randomized controlled trials (RCT) are needed to establish the optimal management strategy for recurrent GBM.

Multimodal treatment for local recurrent malignant gliomas: Resurgery and/or reirradiation followed by chemotherapy

The therapeutic management of recurrent malignant gliomas (MGs) is not determined. Therefore, the efficacy of a multimodal approach and a combination systemic therapy was investigated. A retrospective analysis of 26 MGs patients at first relapse treated with multimodal therapy (chemotherapy plus surgery and/or reirradiation) or chemotherapy alone was performed. Second-line chemotherapy consisted of fotemustine (FTM) in combination with bevacizumab (BEV) (cFTM/BEV) or followed by third-line BEV (sFTM/BEV). Subgroup analyses were performed. Multimodal therapy provided a higher overall response rate (ORR) (73 vs. 47%), disease control rate (DCR) (82 vs. 67%), median progression-free survival (mPFS) (11 vs. 7 months; P=0.08) and median overall survival (mOS) (13 vs. 8 months; P=0.04) compared with chemotherapy. Concomitant FTM/BEV resulted in higher ORR (84 vs. 36%), DCR (92 vs. 57%), mPFS (10 vs. 5 months; P=0.22) and mOS (11 vs. 5.2 months; P=0.15) compared with sFTM/BEV. Methylated patients did not experience additional survival benefits with multimodality treatment but had higher mPFS (10 vs 7.1 months; P=0.33) and mOS (11 vs. 8 months; P=0.33) with cFTM/BEV. Unmethylated patients experienced the greatest survival benefit with the multimodal approach (mPFS: 10 vs. 5 months; mOS 11 vs 6 months; both P=0.02) and cFTM/BEV (mPFS: 5 vs. 2 months; mOS 6 vs. 3.2 months; both P=0.01). In conclusion, in recurrent MGs, multimodal therapy and cFTM/BEV provide survival and response benefits. Methylated patients benefit from a cFTM/BEV but not from a multimodal approach. Notably, unmethylated patients had the highest survival benefit with the two strategies.

THE ROLE OF PHOTODYNAMIC THERAPY IN THE TREATMENT OF PRIMARY, RECURRENT AND METASTATIC MALIGNANT BRAIN TUMORS

Photodynamic therapy is a relevant and promising area for research in the field of clinical neuroonocology. Application of modern developments in the field of laser technologies and new photosensitizers allows us to refer to this field as to high-tech. According to various authors, the inclusion of photodynamic therapy in combined and complex treatments of patients with malignant brain tumors allows achieving overall survival median of patients from 11 to 26 months for primary form of glioblastoma, and from 7.5 to 15 months - for recurrent forms of glioblastoma. Certain results have been achieved in the treatment of patients with metastatic brain lesion. In this publication the authors analyzed and systematized the results of the main clinical studies in the field of fluorescent diagnostics and intraoperative photodynamic therapy of primary, recurrent and metastatic forms of malignant brain tumors.

Peptide-22 and Cyclic RGD Functionalized Liposomes for Glioma Targeting Drug Delivery Overcoming BBB and BBTB

Chemotherapy outcomes for the treatment of glioma remain unsatisfied due to the inefficient drug transport across BBB/BBTB and poor drug accumulation in the tumor site. Nanocarriers functionalized with different targeting ligands are considered as one of the most promising alternatives. However, few studies were reported to compare the targeting efficiency of the ligands and develop nanoparticles to realize BBB/BBTB crossing and brain tumor targeting simultaneously. In this study, six peptide-based ligands (Angiopep-2, T7, Peptide-22, c(RGDfK), D-SP5 and Pep-1), widely used for brain delivery, were selected to decorate liposomes, respectively, so as to compare their targeting ability to BBB or BBTB. Based on the in vitro cellular uptake results on BCECs and HUVECs, Peptide-22 and c(RGDfK) were picked to construct a BBB/BBTB dual-crossing, glioma-targeting liposomal drug delivery system c(RGDfK)/Pep-22-DOX-LP. In vitro cellular uptake demonstrated that the synergetic effect of c(RGDfK) and Peptide-22 could significantly increase the internalization of liposomes on U87 cells. In vivo imaging further verified that c(RGDfK)/Pep-22-LP exhibited higher brain tumor distribution than single ligand modified liposomes. The median survival time of glioma-bearing mice treated with c(RGDfK)/Pep-22-DOX-LP (39.5 days) was significantly prolonged than those treated with free doxorubicin or other controls. In conclusion, the c(RGDfK) and Peptide-22 dual-modified liposome was constructed based on the targeting ability screening of various ligands. The system could effectively overcome BBB/BBTB barriers, target to tumor cells and inhibit the growth of glioma, which proved its potential for improving the efficacy of chemotherapeutics for glioma therapy.

Nano-structures mediated co-delivery of therapeutic agents for glioblastoma treatment: A review

Glioblastoma is a malignant brain tumor and leads to death in most patients. Chemotherapy is a common method for brain cancer in clinics. However, the recent advancements in the chemotherapy of brain tumors have not been efficient enough. With the advancement of nanotechnology, the used drugs can enhance chemotherapy efficiency and increase the access to brain cancers. Combination of therapeutic agents has been recently attracted great attention for glioblastoma chemotherapy. One of the early benefits of combination therapies is the high potential to provide synergistic effects and decrease adverse side effects associated with high doses of single anticancer drugs. Therefore, brain tumor treatments with combination drugs can be considered as a crucial approach for avoiding tumor growth. This review investigates current progress in nano-mediated co-delivery of therapeutic agents with focus on glioblastoma chemotherapy prognosis.

Re-irradiation alternatives for recurrent high-grade glioma

Despite advances in the fields of surgery, chemotherapy and radiotherapy, the prognosis for high-grade glioma (HGG) remains unsatisfactory. The majority of HGG patients experience disease recurrence. To date, no standard treatments have been established for recurrent HGG. Repeat surgery and chemotherapy demonstrate moderate efficacy. As recurrent lesions are usually located within the previously irradiated field, a second course of irradiation was once considered controversial, as it was considered to exhibit unsatisfactory efficacy and radiation-related toxicities. However, an increasing number of studies have indicated that re-irradiation may present an efficacious treatment for recurrent HGG. Re-irradiation may be delivered via conventionally fractionated stereotactic radiotherapy, hypofractionated stereotactic radiation therapy, stereotactic radiosurgery and brachytherapy techniques. In the present review, the current literature regarding re-irradiation treatment for recurrent HGG is summarized with regard to survival outcome and side effects.

The role of 5-aminolevulinic acid in enhancing surgery for high-grade glioma, its current boundaries, and future perspectives: A systematic review

5-Aminolevulinic acid (5-ALA) has been approved as an intraoperative adjunct in glioma surgery in Europe, but not North America. A systematic review was conducted to assess the evidence regarding 5-ALA as a surgical adjunct. The MEDLINE, EMBASE, and CENTRAL databases were searched, using terms relevant to "5-ALA" and "high-grade gliomas." Included studies were based on adults aged ≥18 years who underwent surgical resection/biopsy. No language or date limitations were used. Forty-three studies (1830 patients) were identified. Thirty-six were coordinated by European countries, 2 were in the United States, and none were in Canada. One was randomized, 28 were prospective, and 14 were retrospective. Twenty-six studies assessed the utility of 5-ALA as a diagnostic tool, 24 assessed its influence on the extent of resection (EOR), 9 assessed survival, and 22 reported adverse events. 5-ALA had high sensitivity and positive predictive value, whereas its specificity increased with additional adjuncts. The EOR increased with 5-ALA, but only progression-free survival was significantly influenced. Reporting of adverse events was not systematic. The use of 5-ALA improved tumor visualization and thus enabled a greater EOR and perhaps increased survival. However, additional adjuncts may be necessary for maximizing the specificity of resection and patient safety. Additional parameters, such as patient quality of life and health economic analyses, would be informative. Thus, additional systematic collection of prospective evidence may be necessary for the global incorporation of this potentially valuable surgical adjunct into routine practice. Cancer 2016;122:2469-78. © 2016 American Cancer Society.