Comparison of clinical outcomes and genomic characteristics of single focus and multifocal glioblastoma

Patterns of care and survival in patients with multifocal glioblastoma: A Danish cohort study

Background

This Danish cohort study aims to (1) compare patterns of care (POC) and survival of patients with multifocal glioblastoma (mGBM) to those with unifocal glioblastoma (uGBM), and (2) explore the association of patient-related factors with treatment assignment and prognosis, respectively, in the subgroup of mGBM patients.

Methods

Data on all adults with newly diagnosed, pathology-confirmed GBM between 2015 and 2019 were extracted from the Danish Neuro-Oncology Registry. To compare POC and survival of mGBM to uGBM, we applied multivariable logistic and Cox regression analysis, respectively. To analyze the association of patient-related factors with treatment assignment and prognosis, we established multivariable logistic and Cox regression models, respectively.

Results

In this cohort of 1343 patients, 231 had mGBM. Of those, 42% underwent tumor resection and 41% were assigned to long-course chemoradiotherapy. Compared to uGBM, mGBM patients less often underwent a partial (odds ratio [OR] 0.4, 95% confidence interval [CI] 0.2-0.6), near-total (OR 0.1, 95% CI 0.07-0.2), and complete resection (OR 0.1, 95% CI 0.07-0.2) versus biopsy. mGBM patients were furthermore less often assigned to long-course chemoradiotherapy (OR 0.6, 95% CI 0.4-0.97). Median overall survival was 7.0 (95% CI 5.7-8.3) months for mGBM patients, and multifocality was an independent poor prognostic factor for survival (hazard ratio 1.3, 95% CI 1.1-1.5). In mGBM patients, initial performance, O[6]-methylguanine-DNA methyltransferase promotor methylation status, and extent of resection were significantly associated with survival.

Conclusions

Patients with mGBM were treated with an overall less intensive approach. Multifocality was a poor prognostic factor for survival with a moderate effect. Prognostic factors for patients with mGBM were identified.

The 2021 World Health Organization Central Nervous System Tumor Classification: The Spectrum of Diffuse Gliomas

The 2021 edition of the World Health Organization (WHO) classification of central nervous system tumors introduces significant revisions across various tumor types. These updates, encompassing changes in diagnostic techniques, genomic integration, terminology, and grading, are crucial for radiologists, who play a critical role in interpreting brain tumor imaging. Such changes impact the diagnosis and management of nearly all central nervous system tumor categories, including the reclassification, addition, and removal of specific tumor entities. Given their pivotal role in patient care, radiologists must remain conversant with these revisions to effectively contribute to multidisciplinary tumor boards and collaborate with peers in neuro-oncology, neurosurgery, radiation oncology, and neuropathology. This knowledge is essential not only for accurate diagnosis and staging, but also for understanding the molecular and genetic underpinnings of tumors, which can influence treatment decisions and prognostication. This review, therefore, focuses on the most pertinent updates concerning the classification of adult diffuse gliomas, highlighting the aspects most relevant to radiological practice. Emphasis is placed on the implications of new genetic information on tumor behavior and imaging findings, providing necessary tools to stay abreast of advancements in the field. This comprehensive overview aims to enhance the radiologist's ability to integrate new WHO classification criteria into everyday practice, ultimately improving patient outcomes through informed and precise imaging assessments.

Multifocal and multicentric glioblastoma: Imaging signature, molecular characterization, patterns of spread, and treatment

Multifocal and multicentric glioblastoma (GBM) or collectively, m-GBM, is an imaging diagnosis present in up to 34% of patients with GBM. Compared to unifocal disease, patients with m-GBM have worse outcomes owing to the enhanced aggressive nature of the disease and its resistance to currently available treatments. To improve the understanding of its complex behavior, many associations have been established between the radiologic findings of m-GBM and its gross histology, genetic composition, and patterns of spread. Additionally, the holistic knowledge of the exact mechanisms of m-GBM genesis and progression is crucial for identifying potential targets permitting enhanced diagnosis and treatment. In this review, we aim to provide a comprehensive summary of the cumulative knowledge of the unique molecular biology and behavior of m-GBM and the association of these features with neuroimaging.

Prognostic factors affecting outcome of multifocal or multicentric glioblastoma: A scoping review

It has been reported that patients with multiple lesions have shorter overall survival compared to single lesion in glioblastoma (GBM). Number of lesions can profoundly impact the prognosis and treatment outcome in GBM. In view of the advancement of imaging, multiple GBM (mGBM) lesions are increasingly recognized and reported. The scoping review was conducted and reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension statement for systematic review. Database was searched to collect relevant articles based on predefined eligibility criteria. Our observations suggest that multifocal/multicentric GBM has poorer outcome compared to GBM with singular lesion (sGBM). As the factors influencing the prognosis and outcome is poorly understood and there is no consensus in the existing literature, this review is clinically relevant. As patients with single lesion are more likely to undergo gross total excision, it is likely that further adjuvant treatment may be decided by extent of resection. This review will be helpful for design of further prospective randomized studies for optimal management of mGBM.

Alterations in EGFR and PDGFRA are associated with the localization of contrast-enhancing lesions in glioblastoma

Background

Glioblastoma (GBM) is a malignant brain tumor, with radiological and genetic heterogeneity. We examined the association between radiological characteristics and driver gene alterations.

Methods

We analyzed the driver genes of 124 patients with IDH wild-type GBM with contrast enhancement using magnetic resonance imaging. We used a next-generation sequencing panel to identify mutations in driver genes and matched them with radiological information. Contrast-enhancing lesion localization of GBMs was classified into 4 groups based on their relationship with the subventricular zone (SVZ) and cortex (Ctx).

Results

The cohort included 69 men (55.6%) and 55 women (44.4%) with a mean age of 66.4 ± 13.3 years. EGFR and PDGFRA alterations were detected in 28.2% and 22.6% of the patients, respectively. Contrast-enhancing lesion touching both the SVZ and Ctx was excluded because it was difficult to determine whether it originated from the SVZ or Ctx. Contrast-enhancing lesions touching the SVZ but not the Ctx had significantly worse overall survival than non-SVZ lesions (441 days vs. 897 days, P = .002). GBM touching only the Ctx had a better prognosis (901 days vs. 473 days, P < .001) than non-Ctx lesions and was associated with EGFR alteration (39.4% vs. 13.2%, P = .015). Multiple contrast lesions were predominant in PDGFRA alteration and RB1-wild type (P = .036 and P = .031, respectively).

Conclusions

EGFR alteration was associated with cortical lesions. And PDGFRA alteration correlated with multiple lesions. Our results suggest that clarifying the association between driver genes and tumor localization may be useful in clinical practice, including prognosis prediction.

The clinicopathological features and prognosis of multifocal high-grade gliomas in adults with H3F3A mutation

OBJECTIVES

To explore the clinicopathological features and prognosis of multifocal high-grade gliomas (M-HGGs) with H3F3A mutation in adults.

METHODS

Four adult patients with H3F3A-mutant M-HGGs who were treated at our institution from August 2020 to December 2021 were reviewed, including clinical, pathological and radiologic data. A series of 16 adult patients with M-HGGs without H3F3A mutation was used as a comparative group. Progression-free survival (PFS) and overall survival (OS) were compared between the groups using the Kaplan-Meier method.

RESULTS

All patients were IDH wild-type and TERT wild-type, and P53 was overexpressed. A patient with the H3 G34R mutation and 1 of 3 patients with the H3 K27 M mutation had MGMT promoter methylation. The lesions with the H3 G34R mutation were located in the cerebral hemisphere; the lesions with H3 K27 alterations were mainly in the midline structure, and the cerebral hemisphere could also be involved. One patient underwent subtotal resection (STR), and 3 patients underwent biopsy. All patients received radiotherapy, and the median PFS and OS were 9.5 months and 14.5 months, respectively. The clinical outcomes were similar to those of non-H3F3A-mutated M-HGGs patients (median PFS and OS were 7.0 months and 18.0 months, respectively).

CONCLUSION

We describe the clinicopathological features and outcomes of 4 adult M-HGGs patients with H3F3A mutation, and found this mutation doesn't appear to have a negative outcome with the administration of current therapies.

Newly Diagnosed Multifocal GBM: A Monocentric Experience and Literature Review

Simple Summary

Glioblastoma is an aggressive brain tumor with a dismal prognosis. In a minority of cases, it presents with multiple lesions already at the time of diagnosis, affecting patients’ survival and treatment. Our retrospective study aims to increase the current understanding and define a treatment for this sub-entity, to improve patient survival. Chemoradiotherapy is a also safe and efficacy treatment in patients with multiple lesions. Survival advantages from extensive resection remain unclear.

Abstract

Glioblastomas with multiple foci at presentation (mGBMs) account for 2–35% of all GBMs. mGBMs have limited existing data and no standardized treatment. This study aims to determine their incidence, demographic and clinical features, outcome, and prognostic factors in terms of overall survival. We performed a monocentric retrospective study, reviewing patients treated at the Istituto Oncologico Veneto. Inclusion criteria were: new diagnosis of GBM and presence of multiple lesions on pre-treatment MRI. ECOG PS was used to evaluate clinical condition, RANO criteria for radiological assessment, and CTCAE v5.0 for treatment-related adverse events. The incidence of newly diagnosed mGBM was 7.2% and the study population consisted of 98 patients. Median age was 63 years, M:F ratio of 1.8:1, and a surgical approach was undertaken in 73 patients (mostly partial resection). MGMT was methylated in 47.5%, and 82 patients received active oncological treatment (65.9% radiotherapy plus temozolomide (RT + TMZ)). The disease control rate with RT + TMZ was 63%. Median OS of the entire study population was 10.2 months (95% CI 6.6–13.8), and median PFS was 4.2 months (95% CI 3.2–5.2). The ECOG PS, the extent of resection, and the RT + TMZ were significant prognostic factors in the univariate analysis for OS, but only the RT + TMZ was a significant independent OS predictor in the multivariate analysis (HR = 3.1, 95% IC 1.3–7.7, p = 0.014). The incidence of mGBM is not rare. RT + TMZ is confirmed to be an independent prognostic factor for survival and a safe and effective treatment. When feasible, RT + TMZ should be considered as a possible first-line treatment. The role of the extent of resection is still unclear.

Decreased CD8+ Lymphocytic Infiltration in Multifocal and Multicentric Glioblastomas

Purpose

Multifocal and multicentric glioblastomas (mGBMs) are associated with a poorer prognosis compared to unifocal glioblastoma (uGBM). The presence of CD8⁺ tumor-infiltrating lymphocytes (TILs) is predictive of clinical outcomes in human malignancies. Here, we examined the CD8⁺ lymphocytic infiltration in mGBMs.

Methods

The clinical data of 57 consecutive IDH wildtype primary mGBM patients with histopathological diagnoses were retrospectively reviewed. CD8⁺ TILs were quantitatively evaluated by immunohistochemical staining. The survival function of CD8⁺ TILs was assessed by Kaplan–Meier analysis and Cox proportional hazard models.

Results

No significant difference in the concentration of CD8⁺ TILs was observed among foci from the same patient (P>0.150). The presence of CD8⁺ TILs was similar between multifocal and multicentric GBMs (P=0.885). The concentration of CD8⁺ TILs was significantly lower in mGBMs than in uGBMs (P=0.002). In mGBM patients, the CD8⁺ TIL level was associated with preoperative KPS (P=0.018). The median overall survival (OS) of the 57 mGBMs was 9 months. A low CD8⁺ TIL level (multivariate HR 4.404, 95% CI 1.954-9.926, P=0.0004) was an independent predictor of poor OS, while postoperative temozolomide chemotherapy (multivariate HR 6.076, 95% CI 2.330-15.842, P=0.0002) was independently associated with prolonged OS in mGBMs.

Conclusions

Decreased CD8⁺ TIL levels potentially correlate with unfavorable clinical outcome in mGBMs, suggesting an influence of the local immuno-microenvironment on the progression of mGBMs.

Multifocal high-grade glioma radiotherapy safety and efficacy

Background

Multifocal manifestation of high-grade glioma is a rare disease with very unfavourable prognosis. The pathogenesis of multifocal glioma and pathophysiological differences to unifocal glioma are not fully understood. The optimal treatment of patients suffering from multifocal high-grade glioma is not defined in the current guidelines, therefore individual case series may be helpful as guidance for clinical decision-making.

Methods

Patients with multifocal high-grade glioma treated with conventionally fractionated radiation therapy (RT) in our institution with or without concomitant chemotherapy between April 2011 and April 2019 were retrospectively analysed. Multifocality was neuroradiologically assessed and defined as at least two independent contrast-enhancing foci in the MRI T1 contrast-enhanced sequence. IDH mutational status and MGMT methylation status were assessed from histopathology records. GTV, PTV as well as the V30Gy, V45Gy and D2% volumes of the brain were analysed. Overall and progression-free survival were calculated from the diagnosis until death and from start of radiation therapy until diagnosis of progression of disease in MRI for all patients.

Results

20 multifocal glioma cases (18 IDH wild-type glioblastoma cases, one diffuse astrocytic glioma, IDH wild-type case with molecular features of glioblastoma and one anaplastic astrocytoma, IDH wild-type case) were included into the analysis. Resection was performed in two cases and stereotactic biopsy only in 18 cases before the start of radiation therapy. At the start of radiation therapy patients were 61 years old in median (range 42–84 years). Histopathological examination showed IDH wild-type in all cases and MGMT promotor methylation in 11 cases (55%). Prescription schedules were 60 Gy (2 Gy × 30), 59.4 Gy (1.8 Gy × 33), 55 Gy (2.2 Gy × 25) and 50 Gy (2.5 Gy × 20) in 15, three, one and one cases, respectively. Concomitant temozolomide chemotherapy was applied in 16 cases, combined temozolomide/lomustine chemotherapy was applied in one case and concomitant bevacizumab therapy in one case. Median number of GTVs was three. Median volume of the sum of the GTVs was 26 cm³. Median volume of the PTV was 425.7 cm³ and median PTV to brain ratio 32.8 percent. Median D2% of the brain was 61.5 Gy (range 51.2–62.7) and median V30Gy and V45 of the brain were 59.9 percent (range 33–79.7) and 40.7 percent (range 14.9–64.1), respectively. Median survival was eight months (95% KI 3.6–12.4 months) and median progression free survival after initiation of RT five months (95% CI 2.8–7.2 months). Grade 2 toxicities were detected in eight cases and grade 3 toxicities in four cases consisting of increasing edema in three cases and one new-onset seizure. One grade 4 toxicity was detected, which was febrile neutropenia related to concomitant chemotherapy.

Conclusion

Conventionally fractionated RT with concomitant chemotherapy could safely be applied in multifocal high-grade glioma in this case series despite large irradiation treatment fields.

The characteristic computed tomography findings of pulmonary B-cell non-Hodgkin's lymphoma and their role in predicting patient survival

Background

To assess the value of characteristic computed tomography (CT) findings in predicting the survival of patients with pulmonary B-cell non-Hodgkin's lymphoma (NHL).

Methods

Eighty-four patients who were histopathologically confirmed with pulmonary B-cell NHL between 2004 and 2018 were retrospectively enrolled. All patients underwent chest CT scan at the time of initial diagnosis in our hospital. Characteristic CT findings and clinicopathological features of the patients were analyzed, and Cox regression models were used to determine the relationship of CT findings with overall survival (OS) and progression-free survival (PFS).

Results

Air bronchogram occurred more frequently in patients with early-stage disease, primary pulmonary lymphoma (PPL) and the indolent histological type of lymphoma than in patients with advanced-stage disease, secondary pulmonary lymphoma (SPL), and the aggressive histological type (all P<0.05). The halo sign was observed most in the SPL group (19/48, 40%; P=0.004), while the presence of cross-lobe sign was higher in patients with PPL (13/36, 36%; P=0.010). Pleural involvement and hilar/mediastinal lymphadenopathy were observed more in patients with SPL and the aggressive histological type (33/48 and 27/48; 31/46 and 26/46, respectively; all P<0.05). Survival analyses showed that the number of lung lesions, cross-lobe sign, and pleural involvement were independent prognostic factors for PFS, while the halo sign and pleural involvement were significantly correlated with OS (all P<0.05). More aggressive, advanced-stage cases and male patients showed worse outcomes.

Conclusions

The halo sign and pleural involvement are independent prognostic factors for OS, while the number of lung lesions, cross-lobe sign, and pleural involvement are correlated with PFS.

Multifocal glioblastoma-two case reports and literature review

Background

Multifocal glioblastoma is a rare type of glioblastoma with worse prognosis. In this article, we aimed to report two cases of classical multifocal glioblastoma.

Case presentation

In case 1, a 47-year-old male presented with dizziness, and once had a sudden loss of consciousness accompanied by convulsion of limbs. Contrast-enhanced MRI showed multiple lesions with heterogeneously ring-enhanced characters in the left hemisphere, diagnosed as multifocal glioblastoma. He underwent a craniotomy of all lesions, concurrent radiotherapy and chemotherapy as well as additional chemotherapy of temozolomide. After 2 cycles, repeat MRI showed that the new lesions already occurred and progressed. Eventually, he abandoned the chemotherapy after the 2 cycles and died 1 year later. In case 2, a 71-year-old male presented with a history of headache, left limb weakness, and numbness. Discontinuous convulsion of limbs once occurred. Contrast-enhanced MRI showed multiple lesions located in the right hemisphere, diagnosed as multifocal glioblastoma. He underwent a right frontoparietal craniotomy of the main lesion. Hemorrhage of the residual tumor and pulmonary artery embolism occurred synchronously. Eventually, his family decided not to pursue any further treatment and opted for hospice care and he passed away within 11 days of surgery.

Conclusions

We reported two cases of typical multifocal glioblastoma. Valid diagnosis is crucial; then, resection of multiple lesions and canonical radio-chemotherapy probably bring survival benefits.

A systematic review of multifocal and multicentric glioblastoma

Multiple glioblastoma multiforme (GBM) is classified as multifocal and multicentric GBM according to whether there is communication between the lesions. Multiple GBM is more genetically heterogeneous, aggressive and resistant to chemoradiotherapy than unifocal GBM, and has a worse prognosis. There is no international consensus on the treatment of multiple GBM. This review discusses some paradigms of multiple GBM and focuses on the heterogeneity spread pathway, imaging diagnosis, pathology, molecular characterization and prognosis of multifocal and multicentric GBM. Several promising therapeutic methods of multiple GBM are also recommended.

Multicentric non-enhancing lesions in glioblastoma: A retrospective study

Glioblastoma (GBM) typically presents as a single lesion. Multicentric GBM are defined as well separated lesions on MRI (enhancing and non-enhancing). Multicentric GBM with non-enhancing lesions (MNE-GBM) are rarely described in literature. We aimed at describing the radiologic characteristics, treatment, and clinical course of those patients. The institutional neuropathological database was searched for GBM patients diagnosed between 1/1/2015 and 31/05/2018. All pre-operative MRI brain scans were reviewed to identify patients with MNE-GBM. Electronic medical records and follow-up MRI scans were reviewed to assess progression-free survival (PFS) and overall survival (OS). Out of 149 adult patients with newly diagnosed GBM, 12 met the inclusion criteria of MNE-GBM, all of them presented at least one enhancing lesion. Median follow-up for the MNE-GBM patients was 16.1 months. At last follow-up, all patients had recurrence (median PFS 7.6 months) and eleven patients had deceased. Median OS was 16.2 months (95% CI, 4.1-27.5). Eleven patients received radiotherapy concomitant with temozolomide as initial treatment. Radiation field included all the disease foci (enhancing and non-enhancing lesions) in 8 patients, five of them progressed within the non-enhancing lesion. Three patients did not receive radiation for the entire non-enhancing lesions, and two of them progressed within the non-irradiated areas. In conclusion, MNE-GBM is not rare, and has high risk of aggressive progression within the separate non-enhancing lesion.

Controlled Catheter Movement Affects Dye Dispersal Volume in Agarose Gel Brain Phantoms

The standard of care for treatment of glioblastoma results in a mean survival of only 12 to 15 months. Convection-enhanced delivery (CED) is an investigational therapy to treat glioblastoma that utilizes locoregional drug delivery via a small-caliber catheter placed into the brain parenchyma. Clinical trials have failed to reach their endpoints due to an inability of standard catheters to fully saturate the entire brain tumor and its margins. In this study, we examine the effects of controlled catheter movement on dye dispersal volume in agarose gel brain tissue phantoms. Four different catheter movement control protocols (stationary, continuous retraction, continuous insertion, and intermittent insertion) were applied for a single-port stepped catheter capable of intrainfusion movement. Infusions of indigo carmine dye into agarose gel brain tissue phantoms were conducted during the controlled catheter movement. The dispersal volume (Vd), forward dispersal volume (Vdf), infusion radius, backflow distance, and forward flow distance were quantified for each catheter movement protocol using optical images recorded throughout the experiment. Vd and Vdf for the retraction and intermittent insertion groups were significantly higher than the stationary group. The stationary group had a small but significantly larger infusion radius than either the retracting or the intermittent insertion groups. The stationary group had a greater backflow distance and lower forward flow distance than either the retraction or the intermittent insertion groups. Continuous retraction of catheters during CED treatments can result in larger Vd than traditional stationary catheters, which may be useful for improving the outcomes of CED treatment of glioblastoma. However, catheter design will be crucial in preventing backflow of infusate up the needle tract, which could significantly alter both the Vd and shape of the infusion.

Histological, molecular, clinical and outcomes characteristics of Multiple Lesion Glioblastoma. A retrospective monocentric study and review of literature

BACKGROUND

Multiple lesion glioblastoma (M-GBM) represent a group of GBM patients in which there exist multiple foci of tumor enhancement. The prognosis is poorer than that of single-lesion GBM patients, but this actually is a controversial data. Is unknown whether multifocality has a genetic and molecular basis. Our specific aim is to identify the molecular characteristics of M-GBM by performing a comprehensive multidimensional analysis.

METHODS

The surgical, radiological and clinical outcomes of patients that underwent surgery for GBM at our institution for 2 years have been retrospectively reviewed. We compared the overall survival (OS), progression free survival and extent of resection (EOR) between M-GBM tumors (type I) and S-GBM (single contrast-enhancing lesion, type II).

RESULTS

A total of 177 patients were included in the final cohort, 12 patients had M-GBM and 165 patients had S-GBM. Although patients with M-GBM had higher tumor volumes and midline location, the EOR was not different between both type of lesions. Higher percentage of tumors with EGFR overexpression was detected in M-GBM. PFS and OS was significantly shorter in M-GBM.

CONCLUSIONS

Considering no differences in EOR, patients with M-GBM showed shorter PFS and OS in comparison with S-GBM. Evidences about the M-GBM origin as a multifocal lesion because its molecular profile are suggested.

Molecular characteristics and clinical features of multifocal glioblastoma

INTRODUCTION

Glioblastomas (GBMs) usually occur as a solitary lesion; however, about 0.5-35% present with multiple lesions (M-GBM). The genetic landscape of GBMs have been thoroughly investigated; nevertheless, differences between M-GBM and single-foci GBM (S-GBM) remains unclear. The present study aimed to determine differences in clinical and molecular characteristics between M-GBM and S-GBM.

METHODS

A retrospective review of multifocal/multicentric infiltrative gliomas (M-IG) from our institutional database was performed. Demographics, clinical, radiological, and genetic features were obtained and compared between M-GBM IDH-wild type (IDH-WT) vs 193 S-GBM IDH-WT. Mutations were examined by a targeted next-generation sequencing assay interrogating 315 genes.

RESULTS

33M-IG were identified from which 94% were diagnosed as M-GBM IDH-WT, the remaining 6% were diagnosed as astrocytomas IDH-mutant. M-GBM and S-GBM comparison revealed that EGFR alterations were more frequent in M-GBM (65% vs 42% p = 0.019). Furthermore, concomitant EGFR/PTEN alterations were more common in M-GBM vs. S-GBM (36% vs 19%) as well as compared to TCGA (21%). No statistically significant differences in overall survival were observed between M-GBM and S-GBM; however, within the M-GBM cohort, patients harboring KDR alterations had a worse survival (KDR-altered 6.7 vs KDR-WT 16.6 months, p = 0.038).

CONCLUSIONS

The results of the present study demonstrate that M-GBM genetically resembles S-GBM, however, M-GBM harbor higher frequency of EGFR alterations and co-occurrence of EGFR/PTEN alterations, which may account for their highly malignant and invasive phenotype. Further study of genetic alterations including differences between multifocal and multicentric GBMs are warranted, which may identify potential targets for this aggressive tumor.

Patterns of management and outcomes of unifocal versus multifocal glioblastoma

BACKGROUND

Glioblastoma (GBM) presents as a solitary lesion (unifocal), or as multiple discrete lesions (multifocal). Multifocal GBM may have a worse prognosis as compared to unifocal GBM, but existing data are limited to small institutional series. The purpose of the present study was to evaluate demographic and clinical characteristics of patients with unifocal versus multifocal GBM to highlight demographic differences and clinical outcomes for two groups of patients.

METHODS

The National Cancer Database (NCDB) was queried (2004-2016) for patients newly diagnosed with either unifocal or multifocal GBM. Statistics included Kaplan-Meier overall survival (OS) analysis, along with Cox proportional hazards modeling.

RESULTS

Of 45,268 total patients, 37,483 (82.8%) had unifocal GBM and 7,785 (17.2%) had multifocal GBM. Patients with unifocal GBM more frequently received gross total resection (GTR) (41.2% versus 25.8%, p < 0.001) and conventionally fractionated radiation therapy (RT) (48.2% versus 42.7%, p < 0.001). Patients with multifocal GBM had a higher rate of surgery with biopsy only (34.0% compared to 24.1%, p < 0.001). Median OS was 12.8 months versus 8.3 months (p < 0.001) for patients with unifocal GBM or multifocal GBM, respectively. On multivariate analysis, factors associated with improved OS included unifocal disease, MGMT methylation, RT use, and chemotherapy use.

CONCLUSIONS

This is the largest study to date describing outcomes for patients with multifocal GBM, and it shows that multifocal GBM is associated with a decreased use both of GTR and conventionally fractionated RT, as well as worse median OS. Further research is needed to improve clinical outcomes for patients with multifocal GBM.

The role of TP53 gain-of-function mutation in multifocal glioblastoma

Purpose

The phenotypic and genotypic landscapes in multifocal glioblastoma (MF GBM) cases can vary greatly among lesions. In a MF GBM patient, the rapid development of a secondary lesion was investigated to determine if a unique genetic signature could account for the apparent increased malignancy of this lesion.

Methods

The primary (G52) and secondary (G53) tumours were resected to develop patient derived models followed by functional assays and multiplatform molecular profiling.

Results

Molecular profiling revealed G52 was wild-type for TP53 while G53 presented with a TP53 missense mutation. Functional studies demonstrated increased proliferation, migration, invasion and colony formation in G53.

Conclusion

This data suggests that the TP53 mutation led to gain-of-function phenotypes and resulted in greater overall oncogenic potential of G53.

Electronic supplementary material

The online version of this article (doi:10.1007/s11060-019-03318-5) contains supplementary material, which is available to authorized users.

Clinical implications of multiple glioblastomas: An analysis of prognostic factors and survival to distinguish from their single counterparts

PURPOSE

Glioblastoma (GBM) has the highest fatality rate among primary malignant brain tumors. GBMs with synchronous multiple foci (multiple GBMs) is rarely diagnosed in the clinical scenario. This study aims to compare the clinical characteristics between multiple and single GBMs and to identify factors associated with the survival of GBM and evaluate their effects.

METHODS

We retrospectively reviewed the medical records of patients with primary GBM in a referral medical center in Taiwan who were diagnosed between 2005 and 2016. They were identified from the cancer registry database of the center and followed from the date of diagnosis to october 2018. The primary endpoint of this study was overall survival (OS), and the independent factors for survival were identified through Cox regressions.

RESULTS

A total of 48 patients were identified, of whom 44 GBM (92%) and 4 gliosarcoma (GSM) (8%). Preoperative images showed five (10%) patients had multiple brain lesions. GSM showed a high ratio of multiple lesions (50%) than patients with GBM (5%) (p = 0.05). Those with multiple lesions had significantly worse median OS of 8.2 months compared to patients with a single lesion (16 months, p = 0.03). We found that multiple GBMs was a predictor of worse survival (hazard ratio [HR] = 3.57, 95% confidence interval [95%CI]: 1.26-10.13) after adjusting for other significant predictor of radiotherapy (HR = 0.47, 95%CI: 0.23-0.96).

CONCLUSION

Patients with multiple GBMs had worse survival compared to those with single GBM. GBM patients without post-operative radiotherapy were also a predictor of worse survival.

Prognostic significance of O6-methylguanine-DNA-methyltransferase (MGMT) promoter methylation and isocitrate dehydrogenase-1 (IDH-1) mutation in glioblastoma multiforme patients: A single-center experience in the Middle East region

OBJECTIVES

To determine the prevalence and prognostic value of MGMT promoter methylation and IDH1 mutation in glioblastoma multiforme (GBM) patients from the Middle East.

PATIENTS AND METHODS

Records of patients diagnosed between 2003 and 2015 were reviewed. MGMT promoter methylation was measured using methylation-specific polymerase chain reaction and IDH-1 mutation was reported. The primary endpoint was overall survival (OS).

RESULTS

A total of 110 patients were included. The median age was 51 years and 71 patients (64.5%) were males. The median diameter of GBM was 4.6 cm and 29 patients (26.4%) had multifocal disease. Gross total resection was achieved in 38 patients (24.9%). All patients received adjuvant radiation therapy, and 96 patients (91.4%) received concomitant temozolomide. At a median follow up of 13.6 months, the median OS was 17.2 months, and the OS at 1 and 2 years were 71.6% and 34.8%, respectively. On multivariate analysis, age at diagnosis (HR 1.019; P = 0.044) and multifocality (HR 2.373; P = 0.001) were the only independent prognostic variables. MGMT promoter methylation was found in 28.2% of patients but did not significantly correlate with survival (HR 1.160; P = 0.635). IDH-1 mutation was found in 10% of patients was associated with a non-significant trend for survival improvement (HR 0.502; P = 0.151).

CONCLUSION

Patients with GBM from the Middle East have adequate survival outcomes when given the optimal treatment. In our patient population, MGMT promoter methylation did not seem to correlate with outcomes, but patients with IDH1 mutation had numerically higher survival outcomes.

Morphologic Features on MR Imaging Classify Multifocal Glioblastomas in Different Prognostic Groups

BACKGROUND AND PURPOSE

Multifocal glioblastomas (ie, glioblastomas with multiple foci, unconnected in postcontrast pretreatment T1-weighted images) represent a challenge in clinical practice due to their poor prognosis. We wished to obtain imaging biomarkers with prognostic value that have not been found previously.

MATERIALS AND METHODS

A retrospective review of 1155 patients with glioblastomas from 10 local institutions during 2006-2017 provided 97 patients satisfying the inclusion criteria of the study and classified as having multifocal glioblastomas. Tumors were segmented and morphologic features were computed using different methodologies: 1) measured on the largest focus, 2) aggregating the different foci as a whole, and 3) recording the extreme value obtained for each focus. Kaplan-Meier, Cox proportional hazards, correlations, and Harrell concordance indices (c-indices) were used for the statistical analysis.

RESULTS

Age (P < .001, hazard ratio = 2.11, c-index = 0.705), surgery (P < .001, hazard ratio = 2.04, c-index = 0.712), contrast-enhancing rim width (P < .001, hazard ratio = 2.15, c-index = 0.704), and surface regularity (P = .021, hazard ratio = 1.66, c-index = 0.639) measured on the largest focus were significant independent predictors of survival. Maximum contrast-enhancing rim width (P = .002, hazard ratio = 2.05, c-index = 0.668) and minimal surface regularity (P = .036, hazard ratio = 1.64, c-index = 0.600) were also significant. A multivariate model using age, surgery, and contrast-enhancing rim width measured on the largest foci classified multifocal glioblastomas into groups with different outcomes (P < .001, hazard ratio = 3.00, c-index = 0.853, median survival difference = 10.55 months). Moreover, quartiles with the highest and lowest individual prognostic scores based on the focus with the largest volume and surgery were identified as extreme groups in terms of survival (P < .001, hazard ratio = 18.67, c-index = 0.967).

CONCLUSIONS

A prognostic model incorporating imaging findings on pretreatment postcontrast T1-weighted MRI classified patients with glioblastoma into different prognostic groups.

Survival and recurrence patterns of multifocal glioblastoma after radiation therapy

Purpose

It is hypothesized that multifocal glioblastoma (mGBM) is associated with worse prognosis compared to unifocal disease (uGBM). This study aims to investigate the differences in survival rates and progression patterns of patients between these two groups after radiation therapy.

Patients and methods

We retrospectively analyzed 265 patients with primary GBM undergoing radiation therapy at the Department of Radiation Oncology, University Hospital Heidelberg, Germany, between 2004 and 2013. Of these, 202 (76%) were uGBMs and 63 (24%) were mGBMs. First, progression-free survival (PFS) and overall survival (OS) between groups were compared using the Kaplan-Meier method. Second, univariate and multivariate Cox proportional hazards regression was applied to discern prognostic and predictive factors with PFS and OS in the cohorts. Third, recurrence patterns of uGBMs and mGBMs were assessed on follow-up MRIs and compared using the chi-squared test.

Results

As compared to patients with uGBM, patients with mGBM experienced significantly worse median OS (11.5 vs 14.8 months, P=0.032). Overall, 195 (73.0%) patients experienced tumor progression: 153 (75.7%) patients with uGBM and 46 (73.0%) patients with mGBM. There were no significant differences in PFS between the respective groups (6.5 vs 6.6 months, P=0.750). Of note, concomitant temozolomide treatment was associated with an OS benefit in both uGBM and mGBM by about five months (P=0.006 and P<0.001). Furthermore, there were no significant differences in progression patterns of uGBM and mGBM. Both recurred as unifocal and multifocal disease (P=0.51), and local vs distant brain recurrences occurred similarly in both groups (OR=1.33, P=0.53).

Conclusion

Multifocality is an independent predictor of survival in GBM. Concomitant temozolomide treatment improved OS of patients with mGBM and uGBM. Both disease types showed similar patterns of progression. Current target volume concepts seem to be adequate in both unifocal and multifocal GBMs. GBM, the most common primary brain tumor in adults, is associated with poor survival. We show herein that multifocality is an independent prognostic factor for survival. We also illustrate that the progression patterns of both unifocal and multifocal GBM are similar.

Multiple cerebral gliomas mimicking central nervous system inflammatory demyelinating diseases: A rare case with review of literature

RATIONALE

Multiple cerebral gliomas (MCGs), usually classified into multifocal and multicentric subtypes, represent major diagnostic challenges as their clinical, radiologic, and pathohistological features are not uniform, often mimicking brain metastatic tumors or central nervous system inflammatory demyelinating diseases (IDD).

PATIENT CONCERNS

Here, we report a rare case of MCGs with isolated seizures and 4 lesions in the brain, that was initially misdiagnosed as IDD during treatment.

DIAGNOSIS

The pathological diagnosis was astrocytoma, which was classified as a World Health Organization grade II glioma.

INTERVENTIONS

The patient was treated with dexamethasone and sodium valproate when he was misdiagnosed as having IDD. After the pathological diagnosis was obtained, he was treated with temozolomide and radiotherapy.

OUTCOMES

Three months after the above treatment, the health of the patient had improved; he was asymptomatic, and presented with better radiological manifestations.

LESSONS

Diagnostic imaging is valuable in differential diagnosis. Magnetic resonance spectroscopy is a promising technique for the assessment and characterization of lesions, though its role in definitive diagnosis is not yet defined. Brain tissue biopsy remains the golden standard for definitive diagnosis. In China, for various reasons, craniotomy biopsy is not performed routinely in patients with multiple intracranial lesions, and stereotactic cranial biopsy may be a more viable option because of its safety and cost-effectiveness. In summary, this case demonstrates that MCGs need to be included in the differential diagnosis of unknown intracranial multiple lesions.

Multiple high-grade gliomas: epidemiology, management, and outcome. A systematic review and meta-analysis

Multiple high-grade gliomas (M-HGGs) are well--separated tumors, differentiated as multifocal (MF) and multicentric (MC) by their MRI features. The authors performed a systematic review and meta-analysis of literature examining epidemiology, clinical and radiological characteristics, management, and the overall survival from M-HGGs. According to PRISMA guidelines, a comprehensive review of studies published between January 1990 and January 2017 was carried out. The authors identified studies that examined the prevalence rate, clinical and radiological characteristics, treatment, and overall survival from M-HGGs in patients with HGG. Data were analyzed using a random-effects meta-analysis model. Finally, we systematically reviewed demographic characteristics, lesion location, and surgical and adjuvant treatments. Twenty-three studies were included in this systematic review. The M-HGGs prevalence rate was 19% (95% CI 13-26%) and the hazard ratio of death from M-HGGs in the HGGs population was 1.71 (95% CI 1.49-1.95, p < 0.0001). The MC prevalence rate was 6% (CI 95% 4-10%), whereas MF prevalence rate was 11% (CI 95% 6-20%) (p < 0.0001). There were no statistically significant differences between MF and MC HGGs in gender, lesion location, histological type, and surgical treatment. Survival analysis of MC tumors showed that surgical resection (gross total resection or subtotal resection) is an independent predictor of improved outcome (HR 7.61 for biopsy subgroup, 95% CI 1.94-29.78, p = 0.004). The prevalence of M-HGGs is approximately 20% of HGGs. The clinical relevance of separating M-HGGs in MF and MC tumors remains questionable and its prognostic significance is unclear. When patient status and lesion characteristics make it safe and feasible, cytoreduction should be attempted in patients with M-HGGs because it improves overall survival.

Genetic, epigenetic, and molecular landscapes of multifocal and multicentric glioblastoma

Ten to twenty percent of newly diagnosed glioblastoma (GBM) patients initially present with multiple lesions, termed multifocal or multicentric GBM (M-GBM). The prognosis of these patients is poorer than that of solitary GBM (S-GBM) patients. However, it is unknown whether multifocality has a genetic, epigenetic, or molecular basis. Here, we identified the genetic and epigenetic characteristics of M-GBM by performing a comprehensive analysis of multidimensional data, including imaging, genetic, epigenetic, and gene expression profiles, from 30 M-GBM cases in The Cancer Genome Atlas database and comparing the results with those of 173 S-GBM cases. We found that M-GBMs had no IDH1, ATRX, or PDGFRA mutations and were significantly associated with the mesenchymal subtype. We also identified the CYB5R2 gene to be hypo-methylated and overexpressed in M-GBMs. The expression level of CYB5R2 was significantly associated with patient survival in two major independent GBM cohorts, totaling 758 cases. The IDH1 mutation was markedly associated with CYB5R2 promoter methylation, but the survival influence of CYB5R2 was independent of IDH1 mutation status. CYB5R2 expression was significantly associated with collagen maturation and the catabolic process and immunoregulation pathways. These results reveal that M-GBMs have some underlying genetic and epigenetic characteristics that are associated with poor prognosis and that CYB5R2 is a new epigenetic marker for GBM prognosis.

Multicenter imaging outcomes study of The Cancer Genome Atlas glioblastoma patient cohort: imaging predictors of overall and progression-free survival

BACKGROUND

Despite an aggressive therapeutic approach, the prognosis for most patients with glioblastoma (GBM) remains poor. The aim of this study was to determine the significance of preoperative MRI variables, both quantitative and qualitative, with regard to overall and progression-free survival in GBM.

METHODS

We retrospectively identified 94 untreated GBM patients from the Cancer Imaging Archive who had pretreatment MRI and corresponding patient outcomes and clinical information in The Cancer Genome Atlas. Qualitative imaging assessments were based on the Visually Accessible Rembrandt Images feature-set criteria. Volumetric parameters were obtained of the specific tumor components: contrast enhancement, necrosis, and edema/invasion. Cox regression was used to assess prognostic and survival significance of each image.

RESULTS

Univariable Cox regression analysis demonstrated 10 imaging features and 2 clinical variables to be significantly associated with overall survival. Multivariable Cox regression analysis showed that tumor-enhancing volume (P = .03) and eloquent brain involvement (P < .001) were independent prognostic indicators of overall survival. In the multivariable Cox analysis of the volumetric features, the edema/invasion volume of more than 85 000 mm(3) and the proportion of enhancing tumor were significantly correlated with higher mortality (Ps = .004 and .003, respectively).

CONCLUSIONS

Preoperative MRI parameters have a significant prognostic role in predicting survival in patients with GBM, thus making them useful for patient stratification and endpoint biomarkers in clinical trials.

Genomic predictors of patterns of progression in glioblastoma and possible influences on radiation field design

We present a retrospective investigation of the role of genomics in the prediction of central versus marginal disease progression patterns for glioblastoma (GBM). Between August 2000 and May 2010, 41 patients with GBM and gene expression and methylation data available were treated with radiotherapy with or without concurrent temozolomide. Location of disease progression was categorized as within the high dose (60 Gy) or low dose (46 Gy) volume. Samples were grouped into previously described TCGA genomic groupings: Mesenchymal (m), classical (c), proneural (pn), and neural (n); and were also classified by MGMT-Methylation status and G-Cimp methylation phenotype. Genomic groupings and methylation status were investigated as a possible predictor of disease progression in the high dose region, progression in the low dose region, and time to progression. Based on TCGA category there was no difference in OS (p = 0.26), 60 Gy progression (PN: 71 %, N: 60 %, M: 89 %, C: 83 %, p = 0.19), 46 Gy progression (PN: 57 %, N: 40 %, M: 61 %,C: 50 %, p = 0.8) or time to progression (PN: 9 months, N:15 months, M: 9 months, C: 7 months, p = 0.58). MGMT methylation predicted for improved OS (median 25 vs. 13 months, p = 0.01), improved DFS (median 13 vs. 8 months, p = 0.007) and decreased 60 Gy (p = 0.003) and 46 Gy (p = 0.006) progression. There was a cohort of MGMT methylated patients with late marginal disease progression (4/22 patients, 18 %). TCGA groups demonstrated no difference in survival or progression patterns. MGMT methylation predicted for a statistically significant decrease in in-field and marginal disease progression. There was a cohort of MGMT methylated patients with late marginal progression. Validations of these findings would have implications that could affect radiation field size.