Leptomeningeal disease in glioblastoma: endgame or opportunity?

Leptomeningeal dissemination in H3 K27M- mutant diffuse midline gliomas: clinical characteristics, risk factors, and prognostic insights

PURPOSE

This study aimed to describe the incidence, clinical and pathological features, and outcomes of H3 K27M- mutant Diffuse Midline Glioma (DMG) patients with leptomeningeal dissemination (LMD) and systematically investigate the predictive and prognostic factors to clarify the response to treatment after the onset of LMD.

METHODS

A total of 304 patients diagnosed with DMG from October 17, 2017, to October 17, 2023, were enrolled in this study, of which 32 patients were diagnosed with LMD. Logistic regression analyses were conducted to identify the predictors of LMD, including clinical, molecular, and imaging data. Univariable and multivariable cox regression analyses were used for overall survival (OS) and post-LMD survival (PLS) analysis.

RESULTS

The median OS and PLS were 12.5 and 8.0 months respectively. Tumor with contrast-enhanced lesions reaching ependyma (Ventricular contact type I) was the only independent risk factor for LMD. Male sex and ventricular contact type I were independent risk factors for primary LMD. In all LMD patients, Karnofsky Performance Status (KPS) of ≥ 90 and radiotherapy were statistically significantly associated with longer OS, and primary LMD was significantly associated with shorter OS. Supratentorial location and chemotherapy after LMD diagnosis were independent favorable prognostic factors on PLS. In primary LMD subgroup analysis, radiotherapy was the only independent favorable prognostic factor on OS.

CONCLUSIONS

The association between contrast-enhanced lesions and ventricular involvement is an independent predictive factor for LMD in DMG patients. Radiotherapy and preoperative KPS may contribute to improved overall survival in these patients. Chemotherapy is a potential treatment option following an LMD diagnosis.

Leptomeningeal metastases at recurrence in IDH-wildtype glioblastomas: incidence, risk factors, and prognosis based on postcontrast FLAIR imaging

OBJECTIVES

To comprehensively investigate the incidence, risk factors, and prognosis of leptomeningeal metastases (LM) diagnosed at recurrence in IDH-wildtype glioblastoma patients.

MATERIALS AND METHODS

A total of 734 IDH-wildtype glioblastoma patients were enrolled between 2005 and 2022. LM at recurrence was diagnosed with MRI including postcontrast FLAIR. Logistic analysis for development of LM at recurrence was performed with clinical, molecular, imaging (including tumor volume and distance to subventricular zone via automatic segmentation), and surgical data including extent of resection and ventricular entry. The overall survival (OS) was compared between patients with and without LM at recurrence.

RESULTS

The incidence of LM at recurrence based on postcontrast FLAIR was 10.8% (79 patients). On multivariable analysis, younger age at diagnosis (odds ratio (OR) = 0.98, p = 0.011) and ventricular entry (OR = 3.15, p < 0.001) were independent predictors of LM at recurrence. However, patients with LM at recurrence showed no significant difference in OS from patients without LM (log-rank test; p = 0.461), with median OS of 18.0 (95% confidence interval (CI) 16.2-19.8) and 18.5 (95% CI 16.4-20.7) months in patients with and without LM at recurrence, respectively.

CONCLUSION

The incidence of LM at recurrence is relatively high in IDH-wildtype glioblastoma patients. Younger age and ventricular entry during surgery warrant imaging surveillance for LM at recurrence. As LM at recurrence showed no significant OS compromise and larger extent of resection (EOR) is associated with survival benefits, ventricular entry during maximal safe resection may be acceptable.

KEY POINTS

Question The incidence, risk factors, and prognosis of leptomeningeal metastases (LM) diagnosed at recurrence in IDH-wildtype glioblastoma patients are currently unknown. Findings LM at recurrence occurred in 10.8% of cases, with younger age and ventricular entry as risk factors, but no significant difference in survival outcomes between groups. Clinical relevance The incidence, risk factors, and prognosis of LM at recurrence were investigated in IDH-wildtype glioblastoma patients with postcontrast FLAIR. Younger age and ventricular entry warrant surveillance of LM at recurrence, while the overall survival is not as discouraging as expected.

Leptomeningeal metastases in isocitrate dehydrogenase-wildtype glioblastomas revisited: Comprehensive analysis of incidence, risk factors, and prognosis based on post-contrast fluid-attenuated inversion recovery

BACKGROUND

The incidence of leptomeningeal metastases (LM) has been reported diversely. This study aimed to investigate the incidence, risk factors, and prognosis of LM in patients with isocitrate dehydrogenase (IDH)-wildtype glioblastoma.

METHODS

A total of 828 patients with IDH-wildtype glioblastoma were enrolled between 2005 and 2022. Baseline preoperative MRI including post-contrast fluid-attenuated inversion recovery (FLAIR) was used for LM diagnosis. Qualitative and quantitative features, including distance between tumor and subventricular zone (SVZ) and tumor volume by automatic segmentation of the lateral ventricles and tumor, were assessed. Logistic analysis of LM development was performed using clinical, molecular, and imaging data. Survival analysis was performed.

RESULTS

The incidence of LM was 11.4%. MGMTp unmethylation (odds ratio [OR] = 1.92, P = .014), shorter distance between tumor and SVZ (OR = 0.94, P = .010), and larger contrast-enhancing tumor volume (OR = 1.02, P < .001) were significantly associated with LM. The overall survival (OS) was significantly shorter in patients with LM than in those without (log-rank test; P < .001), with median OS of 12.2 and 18.5 months, respectively. The presence of LM remained an independent prognostic factor for OS in IDH-wildtype glioblastoma (hazard ratio = 1.42, P = .011), along with other clinical, molecular, imaging, and surgical prognostic factors.

CONCLUSIONS

The incidence of LM is high in patients with IDH-wildtype glioblastoma, and aggressive molecular and imaging factors are correlated with LM development. The prognostic significance of LM based on post-contrast FLAIR imaging suggests the acknowledgment of post-contrast FLAIR as a reliable diagnostic tool for clinicians.

Intrathecal chemotherapy for leptomeningeal disease in high-grade gliomas: a systematic review

BACKGROUND

Leptomeningeal disease (LMD) secondary to high grade glioma (HGG), such as glioblastoma (GBM), are characterized by the spread of tumor cells to the leptomeninges which further complicates treatment approaches. Intrathecal (IT) chemotherapy has surfaced as a potential strategy to bypass the blood-brain barrier and address the challenges posed by disseminated disease. Here, we present a review of the safety and efficacy of IT chemotherapy in the treatment of LMD secondary to HGG.

METHODS

A systematic review following PRISMA guidelines was conducted searching PubMed and Embase from January 1995 to September 2022 using specified terms related to IT chemotherapy for LMD. Included articles involved patients diagnosed with LMD from HGG, treated with intrathecal chemotherapy, and provided survival data. Data, including demographics, tumor characteristics, treatment, and survival information, were collected and independently extracted.

RESULTS

A total of 68 patients across 10 clinical studies were diagnosed with LMD from HGG and included in the review. Among these patients, the average age at diagnosis was 44.2 years. GBM was the most common tumor type (n = 58, 85.3%). A majority of the patients presented with recurrent disease (n = 29, 60.4%). The review encompassed various IT chemotherapy regimens, including mafosfamide, thio-TEPA, 5-fluoro-2'-deoxyuridine (FdUrd), methotrexate (MTX), and cytarabine; however, dosages and frequencies were inconsistently reported. The mean progression-free survival (PFS) and overall survival (OS) for this cohort were 7.5 months and 11.7 months, respectively. Common side effects of IT chemotherapy included headaches, nausea, and vomiting, with more severe complications such as myelotoxicity, disseminated intravascular coagulopathy, meningitis, and gastrointestinal toxicity reported in some cases.

CONCLUSION

LMD continues to be an uncommon complication associated with HGG with a poor prognosis. This article provides an overview of the presently available literature on IT chemotherapy for LMD secondary to HGG, and their respective treatment protocols with overall survival attributes. Additional research is warranted to ascertain how to maximize the potential efficacy of IT chemotherapy as a treatment option.

Efficacy and safety of cysto-ventricular catheter implantation for space-occupying cysts arising from glioma and brain metastasis: a retrospective study

BACKGROUND

Cysto-ventricular catheters (CVC) have emerged as promising treatment option for cystic craniopharyngioma and arachnoid cysts, but their effectiveness in treating cysts originating from glioma or brain metastasis (BM) remains limited. This study aimed to analyze the efficacy of CVC in patients with glioma and BM as well as procedure-associated morbidity.

METHODS

This single-center retrospective study included all patients treated with CVC placement for acquired space-occupying cysts deriving from previously treated glioma or BMs between 1/2010 and 12/2021.

RESULTS

A total of 57 patients with a median age of 47 years (IQR 38-63) were identified. Focal neurological deficits were the predominant symptoms in 60% of patients (n = 34), followed by cephalgia in 14% (n = 8), and epileptic seizures in 21.1% (n = 12). Accurate CVC placement was achieved in all but one case requiring revision surgery due to malposition. Three months after CVC implantation, 70% of patients showed symptomatic improvement. Multivariate logistic regression analysis identified the development of space-occupying cysts later in the course of the disease (OR 1.014; p = 0.04) and a higher reduction of cyst-volume postoperatively (OR 1.055; p = 0.05) were significant predictors of postoperative symptomatic improvement following CVC placement. Local cyst recurrence was observed in three cases during follow-up MRI after an average time of 5 months (range 3-9 months). Further complications included secondary malresorptive hydrocephalus in three cases and meningeosis neoplastica in one patient.

CONCLUSIONS

Stereotactic implantation of CVC is an efficient treatment option for patients suffering from symptomatic space-occupying cysts from BMs or glioma, independently from their CNS WHO grade. However, a vigilant approach is crucial regarding potential complications and treatment failures.

Leptomeningeal spread in high-grade gliomas: Is surgery or adjuvant therapy after leptomeningeal spread associated with survival benefit?

PURPOSE

This study aimed to identify prognostic factors associated with survival in patients with high-grade glioma (HGG) after leptomeningeal spread (LMS) and to clarify the behavior and treatment response.

METHODS

This retrospective study included 114 patients with HGGs diagnosed with LMS from August 1, 2014, to July 30, 2021, at our institution. Clinical, radiological, pathological, and outcome data were collected. Univariable and multivariable Cox regression were used for overall survival (OS) and post-LMS survival (PLS) analysis.

RESULTS

The median OS was 17.0 months and the median PLS was 6.0 months. Gross total resection (GTR) after LMS diagnosis and pathology grade III were statistically significantly associated with longer OS in all patients. GTR after LMS diagnosis and nodular LMS were independent favorable prognostic factors on PLS. Non-adjuvant therapy after LMS diagnosis was associated with shorter OS and PLS. In glioblastoma (GBM) subgroup analysis, GTR after LMS diagnosis and secondary LMS were independent favorable prognostic factors on OS. Karnofsky Performance Status (KPS) of ≥80 at LMS diagnosis, chemotherapy after LMS and intrathecal methotrexate (MTX) treatment were statistically significantly associated with longer PLS. MRI type II was a predictor of shorter PLS.

CONCLUSION

The treatment of patients with glioma after LMS diagnosis is very challenging and limited. Safe GTR of tumor and subsequent adjuvant therapy after LMS remains a powerful weapon to improve survival for HGG patients with LMS. Chemotherapy and Intrathecal MTX treatment are feasible treatments after LMS. The extent of tumor dissemination may affect the survival after LMS.

Network-targeting combination therapy of leptomeningeal glioblastoma using multiple synthetic lethal strategies: a case report

Network targeting of disease-specific nodes represents a useful principle for designing combination cancer therapy. In this case of a patient with relapsed leptomeningeal glioblastoma, comprehensive molecular diagnosis led to the identification of a disease network characterized by multiple disease-specific synthetic lethal vulnerabilities involving DNA repair, REDOX homeostasis, and impaired autophagy which suggested a novel network-targeting combination therapy (NTCT). A treatment regimen consisting of lomustine, olaparib, digoxin, metformin, and high dose intravenous ascorbate was employed using the principle of intra-patient dose escalation to deliver the treatment with adequate safety measures to achieve a definitive clinical result.

Revisiting prognostic factors in glioma with leptomeningeal metastases: a comprehensive analysis of clinical and molecular factors and treatment modalities

PURPOSE

To comprehensively investigate prognostic factors, including clinical and molecular factors and treatment modalities, in adult glioma patients with leptomeningeal metastases (LM).

METHODS

Total 226 patients with LM (from 2001 to 2021 among 1495 grade 2 to 4 glioma patients, 88.5% of LM patients being IDH-wildtype) with complete information on IDH mutation, 1p/19q codeletion, and MGMT promoter methylation status were enrolled. Predictors of overall survival (OS) of entire patients were determined by time-dependent Cox analysis, including clinical, molecular, and treatment data. Subgroup analyses were performed for patients with LM at initial diagnosis and LM diagnosed at recurrence (herein, initial and recurrent LM). Identical analyses were performed in IDH-wildtype glioblastoma patients.

RESULTS

Median OS was 17.0 (IQR 9.7-67.1) months, with shorter median OS in initial LM than recurrent LM patients (12.2 vs 20.6 months, P < 0.001). In entire patients, chemotherapy and antiangiogenic therapy were predictors of longer OS, while male sex and initial LM were predictors of shorter OS. In initial LM, higher KPS, chemotherapy, and antiangiogenic therapy were predictors of longer OS, while male sex was a predictor of shorter OS. In recurrent LM, chemotherapy and longer interval between initial glioma and LM diagnoses were predictors of longer OS, while male sex was a predictor of shorter OS. A similar trend was observed in IDH-wildtype glioblastoma.

CONCLUSION

Active chemotherapy and antiangiogenic therapy demonstrated survival benefit in glioma patients with LM. There is consistent female survival advantage, whereas longer interval between initial glioma diagnosis and LM development suggests longer OS in recurrent LM.

Meningeosis Neoplastica in Patients with Glioblastoma: Analysis of 36 Cases

BACKGROUND

Meningeosis neoplastica is a rare manifestation of high-grade gliomas and is usually associated with a devastating outcome. The aim of this bicenter series was to investigate the clinical course and outcome of patients with meningiosis neoplastica.

METHODS

This case series included patients in whom surgery was performed for World Health Organization grade IV primary and secondary glioblastoma (GBM) at the University Medical Center Göttingen, Göttingen, Germany between 2009 and 2021 and Burdenko Institute of Neurosurgery, Moscow, Russia between 2012 and 2018. Inclusion criteria were manifestation of clinical and neuroradiologic signs of leptomeningeal, ependymal, or spinal dissemination of GBM at various time points during the course of the disease.

RESULTS

Meningeosis neoplastica was found in 36 patients. Nine patients developed spinal metastases and 12 ependymal dissemination and 15 patients had a leptomeningeal manifestation of high-grade glioma. The median age of patients at first diagnosis of primary tumor was 56 years. Typical symptoms were headache, nausea, vomiting, and acute paraplegia. The median overall survival was 11 months and progression-free survival was 8 months. Meningeosis neoplastica developed a median 2 months after the initial tumor diagnosis. Salvage therapies included ventriculoperitoneal shunting, decompression of spinal metastases, and spinal radiation therapy. The median time between meningeosis manifestation and death was 3 months.

CONCLUSIONS

Meningeosis neoplastica is a rare manifestation of GBM. It has a poor prognosis. The overall survival after the manifestation of meningeosis was barely longer than 3 months. Salvage therapies did not improve the outcome in our patient cohort.

Safety and Efficacy of Intraventricular Immunovirotherapy with Oncolytic HSV-1 for CNS Cancers

PURPOSE

Oncolytic virotherapy with herpes simplex virus-1 (HSV) has shown promise for the treatment of pediatric and adult brain tumors; however, completed and ongoing clinical trials have utilized intratumoral/peritumoral oncolytic HSV (oHSV) inoculation due to intraventricular/intrathecal toxicity concerns. Intratumoral delivery requires an invasive neurosurgical procedure, limits repeat injections, and precludes direct targeting of metastatic and leptomeningeal disease. To address these limitations, we determined causes of toxicity from intraventricular oHSV and established methods for mitigating toxicity to treat disseminated brain tumors in mice.

EXPERIMENTAL DESIGN

HSV-sensitive CBA/J mice received intraventricular vehicle, inactivated oHSV, or treatment doses (1×107 plaque-forming units) of oHSV, and toxicity was assessed by weight loss and IHC. Protective strategies to reduce oHSV toxicity, including intraventricular low-dose oHSV or interferon inducer polyinosinic-polycytidylic acid (poly I:C) prior to oHSV treatment dose, were evaluated and then utilized to assess intraventricular oHSV treatment of multiple models of disseminated CNS disease.

RESULTS

A standard treatment dose of intraventricular oHSV damaged ependymal cells via virus replication and induction of CD8+ T cells, whereas vehicle or inactivated virus resulted in no toxicity. Subsequent doses of intraventricular oHSV caused little additional toxicity. Interferon induction with phosphorylation of eukaryotic initiation factor-2α (eIF2α) via intraventricular pretreatment with low-dose oHSV or poly I:C mitigated ependyma toxicity. This approach enabled the safe delivery of multiple treatment doses of clinically relevant oHSV G207 and prolonged survival in disseminated brain tumor models.

CONCLUSIONS

Toxicity from intraventricular oHSV can be mitigated, resulting in therapeutic benefit. These data support the clinical translation of intraventricular G207.

Leptomeningeal metastases in glioma revisited: incidence and molecular predictors based on postcontrast fluid-attenuated inversion recovery imaging

OBJECTIVE

Leptomeningeal metastases (LMs) in glioma have been underestimated given their low incidence and the lack of reliable imaging. Authors of this study aimed to investigate the real-world incidence of LMs using cerebrospinal fluid (CSF)–sensitive imaging, namely postcontrast fluid-attenuated inversion recovery (FLAIR) imaging, and to analyze molecular predictors for LMs in the molecular era.

METHODS

A total of 1405 adult glioma (World Health Organization [WHO] grade 2–4) patients underwent postcontrast FLAIR imaging at initial diagnosis and during treatment monitoring between 2001 and 2021. Collected molecular data included isocitrate dehydrogenase (IDH) mutation, 1p/19q codeletion, H3 K27 alteration, and O6-methylguanine–DNA methyltransferase (MGMT) promoter methylation status. LM diagnosis was performed with MRI including postcontrast FLAIR sequences. Logistic regression analysis for LM development was performed with molecular, clinical, and imaging data. Overall survival (OS) was compared between patients with and those without LM.

RESULTS

LM was identified in 228 patients (16.2%), 110 (7.8%) at the initial diagnosis and 118 (8.4%) at recurrence. Among the molecular diagnostics, IDH-wildtype (OR 3.14, p = 0.001) and MGMT promoter unmethylation (OR 1.43, p = 0.034) were independent predictors of LM. WHO grade 4 (OR 10.52, p < 0.001) and nonlobar location (OR 1.56, p = 0.048) were associated with LM at initial diagnosis, whereas IDH-wildtype (OR 5.04, p < 0.001) and H3 K27 alteration (OR 3.39, p = 0.003) were associated with LM at recurrence. Patients with LM had a worse median OS than those without LM (16.7 vs 32.0 months, p < 0.001, log-rank test), which was confirmed as an independent factor on multivariable Cox analysis (p = 0.004).

CONCLUSIONS

CSF-sensitive imaging aids the diagnosis of LM, demonstrating a high incidence of LM in adult gliomas. Furthermore, molecular markers are associated with LM development in glioma, and patients with aggressive molecular markers warrant imaging surveillance for LM.

Preoperative stereotactic radiosurgery in the management of brain metastases and gliomas

Stereotactic radiosurgery (SRS) is the delivery of a high dose ionizing radiation in a highly conformal manner, which allows for significant sparing of nearby healthy tissues. It is typically delivered in 1-5 sessions and has demonstrated safety and efficacy across multiple intracranial neoplasms and functional disorders. In the setting of brain metastases, postoperative and definitive SRS has demonstrated favorable rates of tumor control and improved cognitive preservation compared to conventional whole brain radiation therapy. However, the risk of local failure and treatment-related complications (e.g. radiation necrosis) markedly increases with larger postoperative treatment volumes. Additionally, the risk of leptomeningeal disease is significantly higher in patients treated with postoperative SRS. In the setting of high grade glioma, preclinical reports have suggested that preoperative SRS may enhance anti-tumor immunity as compared to postoperative radiotherapy. In addition to potentially permitting smaller target volumes, tissue analysis may permit characterization of DNA repair pathways and tumor microenvironment changes in response to SRS, which may be used to further tailor therapy and identify novel therapeutic targets. Building on the work from preoperative SRS for brain metastases and preclinical work for high grade gliomas, further exploration of this treatment paradigm in the latter is warranted. Presently, there are prospective early phase clinical trials underway investigating the role of preoperative SRS in the management of high grade gliomas. In the forthcoming sections, we review the biologic rationale for preoperative SRS, as well as pertinent preclinical and clinical data, including ongoing and planned prospective clinical trials.

Preoperative Stereotactic Radiosurgery for Glioblastoma

Glioblastoma is a devastating primary brain tumor with a median overall survival of approximately 15 months despite the use of optimal modern therapy. While GBM has been studied for decades, modern therapies have allowed for a reduction in treatment-related toxicities, while the prognosis has largely been unchanged. Adjuvant stereotactic radiosurgery (SRS) was previously studied in GBM; however, the results were disappointing. SRS is a highly conformal radiation technique that permits the delivery of high doses of ionizing radiation in 1-5 sessions while largely sparing surrounding healthy tissues. Furthermore, studies have shown that the delivery of ablative doses of ionizing radiation within the central nervous system is associated with enhanced anti-tumor immunity. While SRS is commonly used in the definitive and adjuvant settings for other CNS malignancies, its role in the preoperative setting has become a topic of great interest due to the potential for reduced treatment volumes due to the treatment of an intact tumor, and a lower risk of nodular leptomeningeal disease and radiation necrosis. While early reports of SRS in the adjuvant setting for glioblastoma were disappointing, its role in the preoperative setting and its impact on the anti-tumor adaptive immune response is largely unknown. In this review, we provide an overview of GBM, discuss the potential role of preoperative SRS, and discuss the possible immunogenic effects of this therapy.