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

Prognostic impact of second surgical resection in IDH wildtype recurrent glioblastoma following chemo-radiation therapy: a propensity score analysis cohort study

BACKGROUND

The optimal treatment for recurrent glioblastoma (rGBM) remains controversial. We explore the impact of re-surgical resection, compared to solely oncological treatment, in a cohort of isocitrate dehydrogenase (IDH) wild-type rGBM.

METHODS

A retrospective cohort study included adult patients diagnosed with IDHwt rGBM. At recurrence, patients recieved re-surgical resection (re-surgery group - RSG) or further oncological treatments (chemo-radiation group - CRG). Overall survival (OS) and progression-free survival (PFS) were analyzed. A Cox regression model was performed to identify variables related to outcomes. Furthermore, to minimize possible study design-related bias, a propensity score analysis was applied. Additionally, subgroup analysis to explore the role of adjuvant therapies was performed.

RESULTS

In a cohort of 104 patients with rGBM, 44 patients received re-surgical resection. Patients in RSG experienced a longer OS compared to CRG (21 vs. 12 months, p < 0.001); a shorter survival in the CRG was confirmed at the propensity score analysis (HR 2.16, p = 0.004). The median cohort PFS was 4 months. The PFS was similar between the RSG and CRG (6 vs. 4 months). The variables associated with OS were: age, subventricular zone involvement, repeated chemotherapy. The variables associated with PFS were: extent of resection at first surgery, MGMT methylation, no adjuvant therapies, and delayed radiotherapy. At the subgroup analysis, re-irradiation was not associated with OS or PFS benefit in the RSG; adjuvant chemo-radiation therapy offers a survival advantage compared to standard adjuvant chemotherapy in the CRG.

CONCLUSIONS

Re-surgical resection offers a significant survival benefit compared to the sole adjuvant treatment in patients with IDHwt rGBM.

Current trends in reoperation for recurrent glioblastoma: a meta-analysis (2007-2023)

PURPOSE

Despite conflicting evidence, reoperation for recurrent glioblastoma (rGBM) achieving complete resection of enhancing-tumor (CRET) may offer benefits over partial resection or salvage therapy alone. However, pooled analyses remain limited.

METHODS

A systematic search identified rGBM studies comparing reoperation and non-reoperation, including chemotherapy with/without radiotherapy, radiation-based therapies (RBT), and best supportive care (BSC).

RESULTS

Thirty-six studies, comprising 10,738 patients, were included, with 2,806 undergoing reoperation. Nine propensity-score-matched studies and one clinical trial were identified. Mean overall survival (OS) favored reoperation (19.66 months) over chemotherapy with/without radiotherapy (12.56 months, p < 0.00001) and BSC (4.04 months, p < 0.00001), but not over chemotherapy alone (14.60 months) or RBT (14.26 months)(p > 0.05). Multivariate OS favored reoperation over chemotherapy with/without radiation(HR = 0.62,95%CI:0.50-0.76,p < 0.00001), but not to stereotactic radiosurgery (SRS) (HR = 0.52,95%CI:0.25-1.08,p = 0.08) or chemotherapy alone (HR = 0.80,95%CI:0.63-1.00,p = 0.05). Progression-free survival after recurrence (PFS2) was only compared between reoperation and chemotherapy with/without radiotherapy, favoring reoperation (8.36 vs. 4.97 months, p < 0.00001). Multivariate analysis also favored reoperation (HR = 0.56, 95% CI:0.41-0.76,p = 0.0002).The mean post-recurrence survival (PRS) was 12.18 months in the reoperation group, 9.19 months in the chemotherapy with/without radiotherapy, and 9.64 months in SRS. Multivariate PRS favored reoperation over chemotherapy with/without radiotherapy (HR = 0.78, 95%CI: 0.62-0.98,p = 0.04). CRET with < 1 cm3 residual tumor correlated with improved PRS over incomplete resection (HR: 0.54, 95%CI:0.39-0.73, p = 0.04).

CONCLUSION

The role of reoperation in rGBM remains uncertain. While it may improve survival in selected cases, limited high-quality data hinder definitive conclusions. Achieving CRET may correlate with improved PRS over partial resection. Further prospective trials are necessary to guide optimal management of rGBM.

The impact of intraoperative mapping during re-resection in recurrent gliomas: a systematic review

PURPOSE

Previous evidence suggests that glioma re-resection can be effective in improving clinical outcomes. Furthermore, the use of mapping techniques during surgery has proven beneficial for newly diagnosed glioma patients. However, the effects of these mapping techniques during re-resection are not clear. This systematic review aimed to assess the evidence of using these techniques for recurrent glioma patients.

METHODS

A systematic search was performed to identify relevant studies. Articles were eligible if they included adult patients with recurrent gliomas (WHO grade 2-4) who underwent re-resection. Study characteristics, application of mapping, and surgical outcome data on survival, patient functioning, and complications were extracted.

RESULTS

The literature strategy identified 6372 articles, of which 125 were screened for eligibility. After full-text evaluation, 58 articles were included in this review, comprising 5311 patients with re-resection for glioma. Of these articles, 17% (10/58) reported the use of awake or asleep intraoperative mapping techniques during re-resection. Mapping was applied in 5% (280/5311) of all patients, and awake craniotomy was used in 3% (142/5311) of the patients.

CONCLUSION

Mapping techniques can be used during re-resection, with some evidence that it is useful to improve clinical outcomes. However, there is a lack of high-quality support in the literature for using these techniques. The low number of studies reporting mapping techniques may, next to publication bias, reflect limited application in the recurrent setting. We advocate for future studies to determine their utility in reducing morbidity and increasing extent of resection, similar to their benefits in the primary setting.

Emerging Approaches in Glioblastoma Treatment: Modulating the Extracellular Matrix Through Nanotechnology

Glioblastoma's (GB) complex tumor microenvironment (TME) promotes its progression and resistance to therapy. A critical component of TME is the extracellular matrix (ECM), which plays a pivotal role in promoting the tumor's invasive behavior and aggressiveness. Nanotechnology holds significant promise for GB treatment, with the potential to address challenges posed by both the blood-brain barrier and the GB ECM. By enabling targeted delivery of therapeutic and diagnostic agents, nanotechnology offers the prospect of improving treatment efficacy and diagnostic accuracy at the tumor site. This review provides a comprehensive exploration of GB, including its epidemiology, classification, and current treatment strategies, alongside the intricacies of its TME. It highlights nanotechnology-based strategies, focusing on nanoparticle formulations such as liposomes, polymeric nanoparticles, and gold nanoparticles, which have shown promise in GB therapy. Furthermore, it explores how different emerging nanotechnology strategies modulate the ECM to overcome the challenges posed by its high density, which restricts drug distribution within GB tumors. By emphasizing the intersection of nanotechnology and GB ECM, this review underscores an innovative approach to advancing GB treatment. It addresses the limitations of current therapies, identifies new research avenues, and emphasizes the potential of nanotechnology to improve patient outcomes.

Genomic Profiling in Glioma Patients to Explore Clinically Relevant Markers

Gliomas are a heterogeneous group of brain tumors, among which the most aggressive subtype is glioblastoma, accounting for 60% of cases in adults. Available systemic treatment options are few and ineffective, so new approaches to therapies for glioblastoma are in high demand. In total, 131 patients with diffuse glioma were studied. Paired tumor–normal samples were sequenced on the Illumina platform; the panel included 812 genes associated with cancer development. Molecular profiles in clinically distinct groups were investigated. In low-grade glioma (LGG) patients (n = 18), the most common mutations were IDH1/2 (78%), ATRX (33%), TP53 (44%), PIK3CA (17%), and co-deletion 1p/19q (22%). In high-grade glioma (HGG) patients (n = 113), more frequently affected genes were CDKN2A/B (33%), TERTp (71%), PTEN (60%), TP53 (27%), and EGFR (40%). The independent predictors of better prognosis were tumor grade and IDH1/2 mutations. In IDH—wildtype glioblastoma patients, a history of other precedent cancer was associated with worse overall survival (OS), while re-operation and bevacizumab therapy increased OS. Also, among genetic alterations, TERTp mutation and PTEN deletion were markers of poor prognosis. Nine patients received molecular targeted therapy, and the results were evaluated. The search for molecular changes associated with tumor growth and progression is important for diagnosis and choice of therapy.

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.

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

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

Evidence That a Peptide-Drug/p53 Gene Complex Promotes Cognate Gene Expression and Inhibits the Viability of Glioblastoma Cells

Glioblastoma multiform (GBM) is considered the deadliest brain cancer. Conventional therapies are followed by poor patient survival outcomes, so novel and more efficacious therapeutic strategies are imperative to tackle this scourge. Gene therapy has emerged as an exciting and innovative tool in cancer therapy. Its combination with chemotherapy has significantly improved therapeutic outcomes. In line with this, our team has developed temozolomide-transferrin (Tf) peptide (WRAP5)/p53 gene nanometric complexes that were revealed to be biocompatible with non-cancerous cells and in a zebrafish model and were able to efficiently target and internalize into SNB19 and U373 glioma cell lines. The transfection of these cells, mediated by the formulated peptide-drug/gene complexes, resulted in p53 expression. The combined action of the anticancer drug with p53 supplementation in cancer cells enhances cytotoxicity, which was correlated to apoptosis activation through quantification of caspase-3 activity. In addition, increased caspase-9 levels revealed that the intrinsic or mitochondrial pathway of apoptosis was implicated. This assumption was further evidenced by the presence, in glioma cells, of Bax protein overexpression-a core regulator of this apoptotic pathway. Our findings demonstrated the great potential of peptide TMZ/p53 co-delivery complexes for cellular transfection, p53 expression, and apoptosis induction, holding promising therapeutic value toward glioblastoma.

Efficacy of tumour-treating fields therapy in recurrent glioblastoma: A narrative review of current evidence

Recurrent Glioblastoma presents a formidable challenge in oncology due to its aggressive nature and limited treatment options. Tumour-Treating Fields (TTFields) Therapy, a novel therapeutic modality, has emerged as a promising approach to address this clinical conundrum. This review synthesizes the current evidence surrounding the efficacy of TTFields Therapy in the context of recurrent Glioblastoma. Diverse academic databases were explored to identify relevant studies published within the last decade. Strategic keyword selection facilitated the inclusion of studies focusing on TTFields Therapy's efficacy, treatment outcomes, and patient-specific factors. The review reveals a growing body of evidence suggesting the potential clinical benefits of TTFields Therapy for patients with recurrent Glioblastoma. Studies consistently demonstrate its positive impact on overall survival (OS) and progression-free survival (PFS). The therapy's safety profile remains favorable, with mild to moderate skin reactions being the most commonly reported adverse events. Our analysis highlights the importance of patient selection criteria, with emerging biomarkers such as PTEN mutation status influencing therapy response. Additionally, investigations into combining TTFields Therapy with other treatments, including surgical interventions and novel approaches, offer promising avenues for enhancing therapeutic outcomes. The synthesis of diverse studies underscores the potential of TTFields Therapy as a valuable addition to the armamentarium against recurrent Glioblastoma. The narrative review comprehensively explains the therapy's mechanisms, clinical benefits, adverse events, and future directions. The insights gathered herein serve as a foundation for clinicians and researchers striving to optimize treatment strategies for patients facing the challenging landscape of recurrent Glioblastoma.

Surgical Management and Advances in the Treatment of Glioma

The care of patients with both high-grade glioma and low-grade glioma necessitates an interdisciplinary collaboration between neurosurgeons, neuro-oncologists, neurologists and other practitioners. In this review, we aim to detail the considerations, approaches and advances in the neurosurgical care of gliomas. We describe the impact of extent-of-resection in high-grade and low-grade glioma, with particular focus on primary and recurrent glioblastoma. We address advances in surgical methods and adjunct technologies such as intraoperative imaging and fluorescence guided surgery that maximize extent-of-resection while minimizing the potential for iatrogenic neurological deficits. Finally, we review surgically-mediated therapies other than resection and discuss the role of neurosurgery in emerging paradigm-shifts in inter-disciplinary glioma management such as serial tissue sampling and "window of opportunity trials".