glioma

Glioma Guidelines

Glioma Guidelines

The Korean Society for Neuro-Oncology (KSNO) published guidelines for managing adult glioma in 2019, and the National Comprehensive Cancer Network and European Association of Neuro-Oncology published guidelines in September 2021 and March 2021, respectively. However, these guidelines have several different recommendations in practice, including tissue management, adjuvant treatment after surgical resection, and salvage treatment for recurrent/progressive gliomas. Currently, the KSNO guideline working group is preparing an updated version of the guideline for managing adult gliomas 1).

EANO guidelines on the diagnosis and treatment of diffuse gliomas of adulthood. 2)

The National Comprehensive Cancer Network (NCCN) Guidelines for Patients Brain Cancer: Gliomas https://www.nccn.org/patients/guidelines/content/PDF/brain-gliomas-patient.pdf

Zhao et al. systematically searched PubMed, China National Knowledge Infrastructure (CNKI), and Wanfang databases to retrieve guidelines on glioma in China published from the establishment of the database to 24 January 2022. We performed a narrative review of current clinical studies related to the management of glioblastoma, especially in the surgical, targeted, and immunotherapy therapy and tumor-treating fields.

Key content and findings: In this review, 19 guidelines were included, including 8 subclassified as the guideline, 8 subclassified as the consensus, and 3 subclassified as the standard. Two guidelines reported the contents of the system search, 4 guidelines are updated, and 9 guidelines reported the source of funding. At present, most clinical trials on the immune and targeted therapy of glioblastoma are ongoing in China.

China’s guidelines still need to be improved in terms of preciseness, applicability, and editorial independence. In addition, the cooperation in clinical research of glioblastoma in multiple centers needs to be strengthened in China 3).

To follow the revision of the fourth edition of WHO classification and the recent progress on the management of diffuse gliomas, the joint guideline committee of Chinese Glioma Cooperative Group (CGCG), Society for Neuro-Oncology of China (SNO-China) and Chinese Brain Cancer Association (CBCA) updated the clinical practice guideline. It provides recommendations for diagnostic and management decisions, and for limiting unnecessary treatments and cost. The recommendations focus on molecular and pathological diagnostics, and the main treatment modalities of surgery, radiotherapy, and chemotherapy. In this guideline, we also integrated the results of some clinical trials of immune therapies and target therapies, which we think are ongoing future directions. The guideline should serve as an application for all professionals involved in the management of patients with adult diffuse glioma and also a source of knowledge for insurance companies and other institutions involved in the cost regulation of cancer care in China and other countries 4).

1)

Kim YZ, Kim CY, Lim DH. The Overview of Practical Guidelines for Gliomas by KSNO, NCCN, and EANO. Brain Tumor Res Treat. 2022 Apr;10(2):83-93. doi: 10.14791/btrt.2022.0001. PMID: 35545827; PMCID: PMC9098981.
2)

Weller M, van den Bent M, Preusser M, Le Rhun E, Tonn JC, Minniti G, Bendszus M, Balana C, Chinot O, Dirven L, French P, Hegi ME, Jakola AS, Platten M, Roth P, Rudà R, Short S, Smits M, Taphoorn MJB, von Deimling A, Westphal M, Soffietti R, Reifenberger G, Wick W. EANO guidelines on the diagnosis and treatment of diffuse gliomas of adulthood. Nat Rev Clin Oncol. 2021 Mar;18(3):170-186. doi: 10.1038/s41571-020-00447-z. Epub 2020 Dec 8. Erratum in: Nat Rev Clin Oncol. 2022 May;19(5):357-358. PMID: 33293629; PMCID: PMC7904519.
3)

Zhao MJ, Lu T, Ma C, Wang ZF, Li ZQ. A narrative review on the management of glioblastoma in China. Chin Clin Oncol. 2022 Aug;11(4):29. doi: 10.21037/cco-22-18. PMID: 36098100.
4)

Jiang T, Nam DH, Ram Z, Poon WS, Wang J, Boldbaatar D, Mao Y, Ma W, Mao Q, You Y, Jiang C, Yang X, Kang C, Qiu X, Li W, Li S, Chen L, Li X, Liu Z, Wang W, Bai H, Yao Y, Li S, Wu A, Sai K, Li G, Yao K, Wei X, Liu X, Zhang Z, Dai Y, Lv S, Wang L, Lin Z, Dong J, Xu G, Ma X, Zhang W, Zhang C, Chen B, You G, Wang Y, Wang Y, Bao Z, Yang P, Fan X, Liu X, Zhao Z, Wang Z, Li Y, Wang Z, Li G, Fang S, Li L, Liu Y, Liu S, Shan X, Liu Y, Chai R, Hu H, Chen J, Yan W, Cai J, Wang H, Chen L, Yang Y, Wang Y, Han L, Wang Q; Chinese Glioma Cooperative Group (CGCG); Society for Neuro‐Oncology of China (SNO-China); Chinese Brain Cancer Association (CBCA); Chinese Glioma Genome Atlas (CGGA); Asian Glioma Genome Atlas (AGGA) network. Clinical practice guidelines for the management of adult diffuse gliomas. Cancer Lett. 2021 Feb 28;499:60-72. doi: 10.1016/j.canlet.2020.10.050. Epub 2020 Nov 6. PMID: 33166616.

Diffuse midline glioma H3 K27M-altered case series

Diffuse midline glioma H3 K27M-altered case series

2022

Forty-one cases of childhood Diffuse midline glioma H3 K27-altered were collected at Children’s Hospital of Fudan University (39 cases) and Xi’an Children’s Hospital (2 cases), from July 2016 to July 2020. The clinical manifestations, imaging data, histopathology, immunohistochemical phenotype and molecular genetics features, tumor size, site and histological grading were evaluated. Among the 41 cases, 21 were males and 20 females, the age of onset was 3-14 years, the average and median age was 7.6 years and 7.0 years, respectively. The tumor sites were brain stem (n=36) and other locations (n=5). The clinical manifestations were dizziness, gait disturbance, and limb weakness, etc. The MRI features were variable. The histology varied from low-grade to high-grade glioma with neuron differentiation. Immunohistochemistry showed that the tumor cells expressed H3K27M, GFAP, and Olig2. Genetic study showed that 76% (16/21) of tumors had H3F3A gene mutation, mostly accompanied by TP53 (62%, 13/21) missense mutation; five tumors (24%, 5/21) had HIST1H3B gene mutation, accompanied by missense mutations in ACVR1 and PI3K pathway-related gene PIK3CA (4/5) and PIK3R1 (1/5) mutations. The prognosis was dismal with only one alive and others died. The average and median overall survival time was 7 months and 4 months, respectively. Cox multivariate regression analysis showed that age, tumor location, radiologically maximum tumor diameter, histologic grading, and surgical methods were not significantly associated with overall survival rate (P>0.05). Pediatric diffuse midline gliomas with H3K27 alteration have unique clinicopathological and genetic characteristics. The prognosis is poor. The tumor location and histopathologic grading are not related to prognosis. New specific drugs and comprehensive treatment are needed to improve the prognosis 1).

2019

Piccardo et al., from Genoa, Italy. retrospectively analyzed 22 pediatric patients with DMG histologically proved and molecularly classified as H3K27M-mutant (12 subjects) and wild-type (10 subjects) who underwent DWI, Proton magnetic resonance spectroscopic imaging, and ASL performed within 2 weeks of 18F-FDOPA PET. DWI-derived relative minimum apparent diffusion coefficient (rADC min), 1H-MRS data choline/N-acetylaspartate (Cho/NAA), choline/creatine (Cho/Cr), and presence of lactate and relative ASL-derived cerebral blood flow max (rCBF max) were compared with 18F-DOPA uptake Tumor/Normal tissue (T/N) and Tumor/Striatum (T/S) ratios, and correlated with histological and molecular features of DMG. Statistics included Pearson’s chi-square and Mann-Whitney U tests, Spearman’s rank correlation and receiver operating characteristic (ROC) analysis.

The highest degrees of correlation among different techniques were found between T/S, rADC min and Cho/NAA ratio (p < 0.01), and between rCBF max and rADC min (p < 0.01). Significant differences between histologically classified low- and high-grade DMG, independently of H3K27M-mutation, were found among all imaging techniques (p ≤ 0.02). Significant differences in terms of rCBF max, rADC min, Cho/NAA and 18F-DOPA uptake were also found between molecularly classified mutant and wild-type DMG (p ≤ 0.02), even though wild-type DMG included low-grade astrocytomas, not present among mutant DMG. When comparing only histologically defined high-grade mutant and wild-type DMG, only the 18F-DOPA PET data T/S demonstrated statistically significant differences independently of histology (p < 0.003). ROC analysis demonstrated that T/S ratio was the best parameter for differentiating mutant from wild-type DMG (AUC 0.94, p < 0.001).

Advanced MRI and 18F-DOPA PET characteristics of DMG depend on histological features; however, 18F-DOPA PET-T/S was the only parameter able to discriminate H3K27M-mutant from wild-type DMG independently of histology 2).

Baseline diffusion or apparent diffusion coefficient (ADC) characteristics have been shown to predict outcome related to DIPG, but the predictive value of post-radiation ADC is less well understood. ADC parametric mapping (FDM) was used to measure radiation-related changes in ADC and compared these metrics to baseline ADC in predicting progression-free survival and overall survival using a large multi-center cohort of DIPG patients (Pediatric Brain Tumor Consortium-PBTC).

MR studies at baseline and post-RT in 95 DIPG patients were obtained and serial quantitative ADC parametric maps were generated from diffusion-weighted imaging based on T2/FLAIR and enhancement regions of interest (ROIs). Metrics assessed included total voxels with: increase in ADC (iADC); decrease in ADC (dADC), no change in ADC (nADC), fraction of voxels with increased ADC (fiADC), fraction of voxels with decreased ADC (fdADC), and the ratio of fiADC and fdADC (fDM Ratio).

A total of 72 patients were included in the final analysis. Tumors with higher fiADC between baseline and the first RT time point showed a trend toward shorter PFS with a hazard ratio of 6.44 (CI 0.79, 52.79, p = 0.083). In contrast, tumors with higher log mean ADC at baseline had longer PFS, with a hazard ratio of 0.27 (CI 0.09, 0.82, p = 0.022). There was no significant association between fDM derived metrics and overall survival.

Baseline ADC values are a stronger predictor of outcome compared to radiation related ADC changes in pediatric DIPG. We show the feasibility of employing parametric mapping techniques in multi-center studies to quantitate spatially heterogeneous treatment response in pediatric tumors, including DIPG 3).

2017

Meyronet et al., from Lyon analyzed the characteristics of 21 adult H3 K27M-mutant gliomas and compared them with those of 135 adult diffuse gliomas without histone H3 and without isocitrate dehydrogenase (IDH) mutation (IDH/H3 wild type).

The median age at diagnosis in H3 K27M-mutant gliomas was 32 years (range: 18-82 y). All tumors had a midline location (spinal cord n = 6, thalamus n = 5, brainstem n = 5, cerebellum n = 3, hypothalamus n = 1, and pineal region n = 1) and were IDH and BRAF-V600E wild type. The identification of an H3 K27M mutation significantly impacted the diagnosis in 3 patients (14%) for whom the histological aspect initially suggested a diffuse low-grade glioma and in 7 patients (33%) for whom pathological analysis hesitated between a diffuse glioma, ganglioglioma, or pilocytic astrocytoma. Compared with IDH/H3 wild-type gliomas, H3 K27M-mutant gliomas were diagnosed at an earlier age (32 vs 64 y, P < .001), always had a midline location (21/21 vs 21/130, P < .001), less frequently had a methylated MGMT promoter (1/21 vs 52/129, P = .002), and lacked EGFR amplification (0/21 vs 26/128, P = .02). The median survival was 19.6 months in H3 K27M-mutant gliomas and 17 months in IDH/H3 wild-type gliomas (P = .3).

In adults, as in children, H3 K27M mutations define a distinct subgroup of IDH wild-type gliomas characterized by a constant midline location, low rate of MGMT promoter methylation, and poor prognosis 4).

2015

130 cases of DIPG biopsies and previous published data, these procedures appear to have a diagnostic yield and morbidity rates similar to those reported for other brain locations (3.9 % of transient morbidity in our series). In addition, the quality and the quantity of the material obtained allow to (1) confirm the diagnosis, (2) reveal that WHO grading was useless to predict outcome, and (3) perform an extended molecular screen, including biomarkers study and the development of preclinical models. Recent studies reveal that DIPG may comprise more than one biological entity and a unique oncogenesis involving mutations never described in other types of cancers, i.e., histones H3 K27M and activin receptor ACVR1.

Stereotactic biopsies of DIPG can be considered as a safe procedure in well-trained neurosurgical teams and could be incorporated in protocols. It is a unique opportunity to integrate DIPG biopsies in clinical practice and use the biology at diagnosis to drive the introduction of innovative targeted therapies, in combination with radiotherapy 5).

2007

A suboccipital, transcerebellar approach was used to obtain biopsy samples in 24 children.

Two patients suffered deficits. Both had a transient (< 2 months) new cranial nerve palsy; one of these patients also experienced an exacerbation of a preoperative hemiparesis. No patient died during the perioperative period. A histological diagnosis was made in all 24 patients as follows: 22 had a malignant infiltrative astrocytoma, one had a low-grade astrocytoma, and one had a pilocytic astrocytoma. The diagnosis of the latter two patients affected the initial treatment after the biopsy.

The findings of this study imply that stereotactic biopsy sampling of a diffuse pontine tumor is a safe procedure, is associated with minimal morbidity, and has a high diagnostic yield. A nonmalignant tumor was identified in two of the 24 patients in whom the imaging findings were characteristic of a malignant infiltrative astrocytoma. With the advent of new treatment protocols, stereotactic biopsy sampling, which would allow specific tumor characterization of diffuse pontine lesions, may become standard 6).

1)

Li J, Ma YY, Feng J, Zhao D, Ding F, Tian L, Chen R, Zhao R. [Diffuse midline gliomas with H3K27 alteration in children: a clinicopathological analysis of forty-one cases]. Zhonghua Bing Li Xue Za Zhi. 2022 Apr 8;51(4):319-325. Chinese. doi: 10.3760/cma.j.cn112151-20210830-00625. PMID: 35359043.
2)

Piccardo A, Tortora D, Mascelli S, Severino M, Piatelli G, Consales A, Pescetto M, Biassoni V, Schiavello E, Massollo M, Verrico A, Milanaccio C, Garrè ML, Rossi A, Morana G. Advanced MR imaging and (18)F-DOPA PET characteristics of H3K27M-mutant and wild-type pediatric diffuse midline gliomas. Eur J Nucl Med Mol Imaging. 2019 Apr 27. doi: 10.1007/s00259-019-04333-4. [Epub ahead of print] PubMed PMID: 31030232.
3)

Ceschin R, Kocak M, Vajapeyam S, Pollack IF, Onar-Thomas A, Dunkel IJ, Poussaint TY, Panigrahy A. Quantifying radiation therapy response using apparent diffusion coefficient (ADC) parametric mapping of pediatric diffuse intrinsic pontine glioma: a report from the pediatric brain tumor consortium. J Neurooncol. 2019 Feb 27. doi: 10.1007/s11060-019-03133-y. [Epub ahead of print] PubMed PMID: 30810873.
4)

Meyronet D, Esteban-Mader M, Bonnet C, Joly MO, Uro-Coste E, Amiel-Benouaich A, Forest F, Rousselot-Denis C, Burel-Vandenbos F, Bourg V, Guyotat J, Fenouil T, Jouvet A, Honnorat J, Ducray F. Characteristics of H3 K27M-mutant gliomas in adults. Neuro Oncol. 2017 Aug 1;19(8):1127-1134. doi: 10.1093/neuonc/now274. PubMed PMID: 28201752; PubMed Central PMCID: PMC5570304.
5)

Puget S, Beccaria K, Blauwblomme T, Roujeau T, James S, Grill J, Zerah M, Varlet P, Sainte-Rose C. Biopsy in a series of 130 pediatric diffuse intrinsic Pontine gliomas. Childs Nerv Syst. 2015 Oct;31(10):1773-80. doi: 10.1007/s00381-015-2832-1. Epub 2015 Sep 9. PubMed PMID: 26351229.
6)

Roujeau T, Machado G, Garnett MR, Miquel C, Puget S, Geoerger B, Grill J, Boddaert N, Di Rocco F, Zerah M, Sainte-Rose C. Stereotactic biopsy of diffuse pontine lesions in children. J Neurosurg. 2007 Jul;107(1 Suppl):1-4. PubMed PMID: 17647306.

5-aminolevulinic acid fluorescence guided resection of low-grade glioma

5-aminolevulinic acid fluorescence guided resection of low-grade glioma

Radiologically suspected low-grade gliomas (LGG) represent a special challenge for the neurosurgeon during surgery due to their histopathological heterogeneity and indefinite tumor margin. Therefore, new techniques are required to overcome these current surgical drawbacks. Intraoperative visualization of brain tumors with the assistance of 5-aminolevulinic acid (5-ALA) induced protoporphyrin IX (PpIX) fluorescence is one of the major advancements in the neurosurgical field in the last decades. Initially, this technique was exclusively applied for fluorescence-guided surgery of high-grade glioma (HGG). In the last years, the use of 5-ALA was also extended to other indications such as radiologically suspected LGG. Kiesel et al. discussed the current role of 5-ALA for intraoperative visualization of focal malignant transformation within suspected LGG. Furthermore, they discussed the current limitations of the 5-ALA technology in pure LGG which usually cannot be visualized by visible fluorescence. Finally, they introduced new approaches based on fluorescence technology for improved detection of pure LGG tissue such as spectroscopic PpIX quantification fluorescence lifetime imaging of PpIX and confocal microscopy to optimize surgery 1).

A growing body of evidence has revealed the potential utility of 5-aminolevulinic acid (5-ALA) as a surgical adjunct in selected lower-grade gliomas. However, a reliable means of identifying which lower-grade gliomas will fluoresce has not been established.

Widhalm found that 5-ALA induced PpIX fluorescence is capable as a novel intra-operative marker to detect anaplastic foci within initially suspected low-grade gliomas independent of brainshift 2).

Systematic Review

A systematic review of PubMed, Google Scholar, and Cochrane was performed from the date of inception to February 1, 2019. Studies that correlated 5-aminolevulinic acid fluorescence with low-grade glioma in the setting of operative resection were selected. Studies with biopsy only were excluded. Positive fluorescence rates were calculated. The quality index of the selected papers was provided. No patient information was used, so Institutional Review Board approval and patient consent were not required.

A total of 12 articles met the selection criteria with 244 histologically confirmed low-grade glioma patients who underwent microsurgical resection. All patients received 20 mg/kg body weight of 5-aminolevulinic acid. Only 60 patients (n = 60/244; 24.5%) demonstrated visual intraoperative 5-aminolevulinic acid fluorescence. The extent of resection was reported in 4 studies; however, the data combined low- and high-grade tumors. Only 2 studies reported on tumor location. Only 3 studies reported on clinical outcomes. The Zeiss OPMI Pentero microscope was most commonly used across all studies. The average quality index was 14.58 (range: 10-17), which correlated with an overall good quality.

There is an overall low correlation between 5-aminolevulinic acid fluorescence and low-grade glioma. Advances in visualization technology and using standardized fluorescence quantification methods may further improve the visualization and reliability of 5-aminolevulinic acid fluorescence in low-grade glioma resection 3).

Case series

Müther et al. investigated a cohort of patients with WHO Grade 2 glioma and WHO Grade 3 gliomas who received 5-ALA before resection at a single institution. Using a logistic regression-based model, they evaluated 14 clinical and molecular variables considered plausible determinants of fluorescence. They then distilled the most predictive features to develop a model for predicting both fluorescence and tumor grade. They also explored the relationship between intraoperative fluorescence and diagnostic molecular markers.

One hundred seventy-nine subjects were eligible for inclusion. Our logistic regression classifier accurately predicted intraoperative fluorescence in our cohort with 91.9% accuracy and revealed enhancement as the singular variable in determining intraoperative fluorescence. There was a direct relationship between enhancement on MRI and the likelihood of observed fluorescence. Observed fluorescence correlated with MIB-1 index but not with isocitrate dehydrogenase (IDH) status, 1p19q codeletion, or methylguanine DNA methyltransferase promoter methylation.

They demonstrated a strong correlation between enhancement on preoperative MRI and the likelihood of visible fluorescence during surgery in patients with intermediate-grade glioma. The analysis provides a robust method for predicting 5-ALA-induced fluorescence in patients with grade II and grade III gliomas 4).

Valdés et al. describe their initial experience with 5-aminolevulinic acid (ALA)-induced PpIX fluorescence in twelve patients with presumed LGGs after receiving 20 mg/kg of ALA approximately 3 hours prior to surgery under an institutional review board-approved protocol.

Intraoperative assessments of the resulting PpIX emissions using both qualitative, visible fluorescence and quantitative measurements of PpIX concentration were obtained from tissue locations that were subsequently biopsied and evaluated histopathologically. Mixed models for random effects and receiver operating characteristic curve analysis for diagnostic performance were performed on the fluorescence data relative to the gold-standard histopathology.

Five of the 12 LGGs (1 ganglioglioma, 1 oligoastrocytoma, 1 pleomorphic xanthoastrocytoma, 1 oligodendroglioma, and 1 ependymoma) demonstrated at least 1 instance of visible fluorescence during surgery. Visible fluorescence evaluated on a specimen-by-specimen basis yielded a diagnostic accuracy of 38.0% (cutoff threshold: visible fluorescence score ≥ 1, area under the curve = 0.514). Quantitative fluorescence yielded a diagnostic accuracy of 67% (for a cutoff threshold of the concentration of PpIX [CPpIX] > 0.0056 μg/ml, area under the curve = 0.66). The authors found that 45% (9/20) of nonvisibly fluorescent tumor specimens, which would have otherwise gone undetected, accumulated diagnostically significant levels of CPpIX that were detected quantitatively.

The authors’ initial experience with ALA-induced PpIX fluorescence in LGGs concurs with other literature reports that the resulting visual fluorescence has poor diagnostic accuracy. However, the authors also found that diagnostically significant levels of CPpIX do accumulate in LGGs, and the resulting fluorescence emissions are very often below the detection threshold of current visual fluorescence imaging methods. Indeed, at least in the authors’ initial experience reported here, if quantitative detection methods are deployed, the diagnostic performance of ALA-induced PpIX fluorescence in LGGs approaches the accuracy associated with visual fluorescence in HGGs 5).

1)

Kiesel B, Freund J, Reichert D, Wadiura L, Erkkilae MT, Woehrer A, Hervey-Jumper S, Berger MS, Widhalm G. 5-ALA in Suspected Low-Grade Gliomas: Current Role, Limitations, and New Approaches. Front Oncol. 2021 Jul 30;11:699301. doi: 10.3389/fonc.2021.699301. PMID: 34395266; PMCID: PMC8362830.
2)

Widhalm G. Intra-operative visualization of brain tumors with 5-aminolevulinic acid-induced fluorescence. Clin Neuropathol. 2014 Jul-Aug;33(4):260-78. PubMed PMID: 24986206.
3)

Almekkawi AK, El Ahmadieh TY, Wu EM, Abunimer AM, Abi-Aad KR, Aoun SG, Plitt AR, El Tecle NE, Patel T, Stummer W, Bendok BR. The Use of 5-Aminolevulinic Acid in Low-Grade Glioma Resection: A Systematic Review. Oper Neurosurg (Hagerstown). 2020 Jul 1;19(1):1-8. doi: 10.1093/ons/opz336. Erratum in: Oper Neurosurg (Hagerstown). 2020 Jul 1;19(1):107. PMID: 31828346.
4)

Müther M, Jaber M, Johnson TD, Orringer DA, Stummer W. A Data-Driven Approach to Predicting 5-Aminolevulinic Acid-Induced Fluorescence and World Health Organization Grade in Newly Diagnosed Diffuse Gliomas. Neurosurgery. 2022 Mar 16. doi: 10.1227/NEU.0000000000001914. Epub ahead of print. PMID: 35285461.
5)

Valdés PA, Jacobs V, Harris BT, Wilson BC, Leblond F, Paulsen KD, Roberts DW. Quantitative fluorescence using 5-aminolevulinic acid-induced protoporphyrin IX biomarker as a surgical adjunct in low-grade glioma surgery. J Neurosurg. 2015 Jul 3:1-10. [Epub ahead of print] PubMed PMID: 26140489.

Fluorescein sodium guided resection of high-grade glioma

Fluorescein sodium guided resection of high-grade glioma

Naik et al. compared 5 aminolevulinic acid fluorescence guided resection of high-grade glioma, Fluorescein sodium guided resection of high-grade glioma. (FS), and Intraoperative magnetic resonance imaging-guided resection of high-grade glioma (IMRI) with no image guidance to determine the best intraoperative navigation method to maximize rates of gross total resection (GTR) and outcomes. A frequentist network meta-analysis was performed following standard PRISMA guidelines (PROSPERO registration CRD42021268659). Surface-under-the-cumulative ranking (SUCRA) analysis was executed to hierarchically rank modalities by the outcome of interest. Heterogeneity was measured by the I2 statistic. Publication bias was assessed by funnel plots and the use of Egger’s test. Statistical significance was determined by p < 0.05. Twenty-three studies were included for analysis with a total of 2,643 patients. Network meta-analysis comparing 5-ALA, IMRI, and FS was performed. The primary outcome assessed was the rate of GTR. Analysis revealed the superiority of all intraoperative navigation to control (no navigation). SUCRA analysis revealed the superiority of IMRI + 5-ALA, IMRI alone, followed by FS, and 5-ALA. Overall survival (OS) and progression-free survival (PFS) were also examined. FS (vs. control) was associated with improved OS, while IMRI was associated with improved PFS (vs. control, FS, and 5-ALA). Intraoperative navigation using IMRI, FS, and 5-ALA lead to greater rates of GTR in HGGs. FS and 5-ALA also yielded improvement in OS and PFS. Further studies are needed to evaluate differences in survival benefit, operative duration, and cost 1).

Fluorescein can be used as a viable alternative to 5-ALA for intraoperative fluorescent guidance in brain tumor surgery. Comparative, prospective, and randomized studies are much needed 2).

5-ALA fluorescence-guided surgery has shortcomings such as drug’s phototoxicity, extortionate price, and not being approved by Food and Drug Administration, which limited its widespread application.

Due to the above limitations, sodium fluorescein guided surgery had been paid more attention by neurosurgeons than 5-ALA. FL is an easily available and biosafe fluorescein dye with a peak excitation at 465 to 490 nm and emission between 500 and 550 nm and has been used extensively and safely for many years especially in ophthalmology 3) 4).

5 aminolevulinic acid is still the preferred and more established fluorescent dye used during high-grade gliomas resection, with Fluorescein sodium gaining-attention, really cheaper and more ductile alternative 5).

The use of fluorescein fluorescence-guided stereotactic needle biopsy has been shown to improve diagnostic accuracy and to expedite operative procedure in the stereotactic needle biopsy of high-grade gliomas.

see Fluoropen.

The first use of fluorescence for brain tumour surgery was in 1948 by G.E. Moore 6) using fluorescein sodium, a strongly fluorescing and non-toxic (apart from rare anaphylaxis 7) compound). In malignant brain tumours with their inherent blood-brain barrier breakdown, fluorescein is extravasated and might serve to mark tumours.

Today, fluorescein sodium is again under scrutiny 8) 9). using a novel filter system by Zeiss (YELLOW 560) for the microscope. This filter visualises fluorescein and allows good background discrimination. Furthermore, fluorescein can be injected any time and is low in cost. Nevertheless, its use in brain tumour surgery is off-label and thus restricted to clinical studies. Little is known about the best timing of i.v. fluorescein application before resection. Injecting fluorescein too early might result in unspecific propagation with oedema, whereas acute injections might be useful for detecting abnormally perfused tumour tissue. Levels in the blood will be high, especially with acute injections, leading to fluorescence of all perfused brain tissue. Such time-resolved in- formation on the specificity of fluorescein are not available.

Overall, Schwake et al observed no clear value of fluorescein in a small study, which they closed prematurely. Clearly, further work elucidating optimal timing and dosing of fluorescein is warranted. 10)

Sodium fluorescein (SF) was first used for the identification of different types of brain tumors in 1948 11).

Since then, the use of SF and others fluorescent tracers have been described in literature particularly that dealing with glioblastoma multiforme resection 12) 13) 14)

Metastatic lesion were also enhanced by SF 15). 16).

Also in skull base tumors 17).

“Fluorescein sodium”, the sodium salt of fluorescein, is used extensively as a diagnostic tool in the field of ophthalmology and optometry, where topical fluorescein is used in the diagnosis of corneal abrasions, corneal ulcers and herpetic corneal infections. It is also used in rigid gas permeable contact lens fitting to evaluate the tear layer under the lens. It is available as sterile single-use sachets containing lint-free paper applicators soaked in fluorescein sodium.

Intravenous or oral fluorescein is used in fluorescein angiography in research and to diagnose and categorize vascular disorders including retinal disease macular degeneration, diabetic retinopathy, inflammatory intraocular conditions, and intraocular tumors. It is also being used increasingly during surgery for brain tumors.

Diluted fluorescein dye has been used to localise multiple muscular ventricular septal defects during open heart surgery and confirm the presence of any residual defects.

Intravenous fluorescein sodium has been used during resection of high-grade gliomas to help the surgeon visualize tumor margins. Several studies have reported improved rates of gross total resection (GTR) using high doses of fluorescein sodium under white light. The introduction of a fluorescein-specific camera that allows for high-quality intraoperative imaging and use of very low dose fluorescein has drawn new attention to this fluorophore.

Fluorescein sodium does not appear to selectively accumulate in astrocytoma cells but in extracellular tumor cell rich locations, suggesting that fluorescein is a marker for areas of compromised blood brain barrier within high grade astrocytoma. Fluorescein fluorescence appears to correlate intraoperatively with the areas of MR enhancement, thus representing a practical tool to help the surgeon achieve GTR of the enhancing tumor regions 18).

Magnetic resonance diffusion tensor imaging (MR-DTI) and fluorescein sodium dyeing guiding for surgery of glioma located in brain motor functional areas can increase the gross total resection rate, decrease the paralysis rate caused by surgery, and improve patient quality of life compared with traditional glioma surgery 19).

Intrathecal fluorescein (ITF) is extremely specific and very sensitive for detecting intraoperative CSF leaks. Although false negatives can occur, these patients do not appear to be at risk for postoperative CSF leak. The use of ITF may help surgeons prevent postoperative CSF leaks by intraoperatively detecting and confirming a watertight repair 20).

1)

Naik A, Smith EJ, Barreau A, Nyaeme M, Cramer SW, Najafali D, Krist DT, Arnold PM, Hassaneen W. Comparison of fluorescein sodium, 5-ALA, and intraoperative MRI for resection of high-grade gliomas: A systematic review and network meta-analysis. J Clin Neurosci. 2022 Feb 22;98:240-247. doi: 10.1016/j.jocn.2022.02.028. Epub ahead of print. PMID: 35219089.
2)

Hansen RW, Pedersen CB, Halle B, Korshoej AR, Schulz MK, Kristensen BW, Poulsen FR. Comparison of 5-aminolevulinic acid and sodium fluorescein for intraoperative tumor visualization in patients with high-grade gliomas: a single-center retrospective study. J Neurosurg. 2019 Oct 4:1-8. doi: 10.3171/2019.6.JNS191531. [Epub ahead of print] PubMed PMID: 31585425.
3)

Novotny H. R., Alvis D. L. A method of photographing fluorescence in circulating blood in the human retina. Circulation. 1961;24:82–86. doi: 10.1161/01.cir.24.1.82.
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Kwan A. S. L., Barry C., McAllister I. L., Constable I. Fluorescein angiography and adverse drug reactions revisited: the Lions Eye experience. Clinical and Experimental Ophthalmology. 2006;34(1):33–38. doi: 10.1111/j.1442-9071.2006.01136.x.
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Acerbi F, Restelli F, De Laurentis C, Falco J, Cavallo C, Broggi M, Höhne J, Schebesch KM, Schiariti M, Ferroli P. Fluorescent tracers in neurosurgical procedures: an European survey. J Neurosurg Sci. 2018 Jul 17. doi: 10.23736/S0390-5616.18.04494-6. [Epub ahead of print] PubMed PMID: 30014688.
6)

Moore GE, Peyton WT, French LA, Walker WW (1948) The clinical use of fluorescein in neurosurgery; the localization of brain tumors. J Neurosurg 5:392–398
7)

Dilek O, Ihsan A, Tulay H (2011) Anaphylactic reaction after fluo- rescein sodium administration during intracranial surgery. J Clin Neurosci 18:430–431
8)

Acerbi F, Broggi M, Eoli M, Anghileri E, Cuppini L, Pollo B, Schiariti M, Visintini S, Ori C, Franzini A, Broggi G, Ferroli P (2013) Fluorescein-guided surgery for grade IV gli- omas with a dedicated filter on the surgical microscope: pre- liminary results in 12 cases. Acta Neurochir (Wien) 155: 1277–1286
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Schebesch KM, Proescholdt M, Höhne J, Hohenberger C, Hansen E, Reimenschneider MJ, Ullrich W, Doenitz C, Schlair J, Lange M, Brawanski A (2013) Sodium fluorescein-guided resection under the YELLOW 560 nm surgical microscope filter in malignant brain tumor surgery—a feasibility study. Acta Neurochir (Wien) 155:693–699
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Schwake M, Stummer W, Suero Molina EJ, Wölfer J. Simultaneous fluorescein sodium and 5-ALA in fluorescence-guided glioma surgery. Acta Neurochir (Wien). 2015 May;157(5):877-9. doi: 10.1007/s00701-015-2401-0. Epub 2015 Mar 28. PubMed PMID: 25820632.
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Moore GE, Peyton WT, French LA, Walker WW. The clinical use of fluorescein in neurosurgery. J Neurosurg. 1948;5:392–8.
12)

Chae MP, Song SW, Park SH, Park CK. Experience with 5- aminolevulinic Acid in fluorescence-guided resection of a deep sylvian meningioma. J Korean Neurosurg Soc. 2012;52:558–60.
13)

Kuroiwa T, Kajimoto Y, Ohta T. Development of a fluorescein operative microscope for use during malignant glioma surgery: A technical note and preliminary report. Surg Neurol. 1998;50:41–9.
14)

Kuroiwa T, Kajimoto Y, Ohta T. Comparison between operative findings on malignant glioma by a fluorescein surgical microscopy and histological findings. Neurol Res. 1999;21:130–4.
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Okuda T, Kataoka K, Taneda M. Metastatic brain tumor surgery using fluorescein sodium: Technical note. Minim Invasive Neurosurg. 2007;50:382–4.
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da Silva CE, da Silva JL, da Silva VD. Use of sodium fluorescein in skull base tumors. Surg Neurol Int. 2010;1:70.
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Diaz RJ, Dios RR, Hattab EM, Burrell K, Rakopoulos P, Sabha N, Hawkins C, Zadeh G, Rutka JT, Cohen-Gadol AA. Study of the biodistribution of fluorescein in glioma-infiltrated mouse brain and histopathological correlation of intraoperative findings in high-grade gliomas resected under fluorescein fluorescence guidance. J Neurosurg. 2015 Jun;122(6):1360-9. doi: 10.3171/2015.2.JNS132507. Epub 2015 Apr 3. PubMed PMID: 25839919.
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Liu JG, Yang SF, Liu YH, Wang X, Mao Q. Magnetic resonance diffusion tensor imaging with fluorescein sodium dyeing for surgery of gliomas in brain motor functional areas. Chin Med J (Engl). 2013 Jul;126(13):2418-23. PubMed PMID: 23823811.
20)

Raza SM, Banu MA, Donaldson A, Patel KS, Anand VK, Schwartz TH. Sensitivity and specificity of intrathecal fluorescein and white light excitation for detecting intraoperative cerebrospinal fluid leak in endoscopic skull base surgery: a prospective study. J Neurosurg. 2016 Mar;124(3):621-6. doi: 10.3171/2014.12.JNS14995. Epub 2015 Aug 21. PubMed PMID: 26295912.

Diffuse midline glioma H3 K27-altered treatment

Diffuse midline glioma H3 K27-altered treatment

Stereotactic biopsy is being performed in some centers, and may become routine when therapies specifically targeted to these mutations become available.

Diffuse midline glioma H3 K27-altered have no effective treatment, and their location and diffuse nature render them inoperable. Radiation therapy remains the only standard of care for this devastating disease.

Until recently biopsies were considered not informative enough and therefore not recommended.

GD2-CAR T cell therapy

see GD2-CAR T cell therapy

Systemic administration of chemotherapeutic agents is often hindered by the blood brain barrier (BBB), and even drugs that successfully cross the barrier may suffer from unpredictable distributions. The challenge in treating this deadly disease relies on effective delivery of a therapeutic agent to the bulk tumor as well as infiltrating cells. Therefore, methods that can enhance drug delivery to the brain are of great interest. Convection-enhanced delivery (CED) is a strategy that bypasses the BBB entirely and enhances drug distribution by applying hydraulic pressure to deliver agents directly and evenly into a target region. This technique reliably distributes infusate homogenously through the interstitial space of the target region and achieves high local drug concentrations in the brain. Moreover, recent studies have also shown that continuous delivery of drug over an extended period of time is safe, feasible, and more efficacious than standard single session CED. Therefore, CED represents a promising technique for treating midline tumors with the H3K27M mutation 1).

Based on the molecular heterogeneity observed in this tumor type, personalized treatment is considered to substantially improve therapeutic options. Therefore, clinical evidence for therapy, guided by comprehensive molecular profiling, is urgently required. In this study, we analyzed feasibility and clinical outcomes in a cohort of 12 H3K27M glioma cases treated at two centers. Patients were subjected to personalized treatment either at primary diagnosis or disease progression and received backbone therapy including focal irradiation. Molecular analyses included whole-exome sequencing of tumor and germline DNA, RNA-sequencing, and transcriptomic profiling. Patients were monitored with regular clinical as well as radiological follow-up. In one case, liquid biopsy of cerebrospinal fluid (CSF) was used. Analyses could be completed in 83% (10/12) and subsequent personalized treatment for one or more additional pharmacological therapies could be recommended in 90% (9/10). Personalized treatment included inhibition of the PI3K/AKT/mTOR pathway (3/9), MAPK signaling (2/9), immunotherapy (2/9), receptor tyrosine kinase inhibition (2/9), and retinoic receptor agonist (1/9). The overall response rate within the cohort was 78% (7/9) including one complete remission, three partial responses, and three stable diseases. Sustained responses lasting for 28 to 150 weeks were observed for cases with PIK3CA mutations treated with either miltefosine or everolimus and additional treatment with trametinib/dabrafenib in a case with BRAFV600E mutation. Immune checkpoint inhibitor treatment of a case with increased tumor mutational burden (TMB) resulted in complete remission lasting 40 weeks. Median time to progression was 29 weeks. Median overall survival (OS) in the personalized treatment cohort was 16.5 months. Last, we compared OS to a control cohort (n = 9) showing a median OS of 17.5 months. No significant difference between the cohorts could be detected, but long-term survivors (>2 years) were only present in the personalized treatment cohort. Taken together, we present the first evidence of clinical efficacy and an improved patient outcome through a personalized approach at least in selected cases of H3K27M glioma 2).

Findings suggest that targeting PLK1 with small-molecule inhibitors, in combination with radiation therapy, will hold a novel strategy in the treatment of Diffuse intrinsic pontine glioma (DIPG) that warrants further investigation 3).

1)

Himes BT, Zhang L, Daniels DJ. Treatment Strategies in Diffuse Midline Gliomas With the H3K27M Mutation: The Role of Convection-Enhanced Delivery in Overcoming Anatomic Challenges. Front Oncol. 2019 Feb 8;9:31. doi: 10.3389/fonc.2019.00031. PMID: 30800634; PMCID: PMC6375835.
2)

Gojo J, Pavelka Z, Zapletalova D, Schmook MT, Mayr L, Madlener S, Kyr M, Vejmelkova K, Smrcka M, Czech T, Dorfer C, Skotakova J, Azizi AA, Chocholous M, Reisinger D, Lastovicka D, Valik D, Haberler C, Peyrl A, Noskova H, Pál K, Jezova M, Veselska R, Kozakova S, Slaby O, Slavc I, Sterba J. Personalized Treatment of H3K27M-Mutant Pediatric Diffuse Gliomas Provides Improved Therapeutic Opportunities. Front Oncol. 2020 Jan 10;9:1436. doi: 10.3389/fonc.2019.01436. PMID: 31998633; PMCID: PMC6965319.
3)

Amani V, Prince EW, Alimova I, Balakrishnan I, Birks D, Donson AM, Harris P, Levy JM, Handler M, Foreman NK, Venkataraman S, Vibhakar R. Polo-like Kinase 1 as a potential therapeutic target in Diffuse Intrinsic Pontine Glioma. BMC Cancer. 2016 Aug 18;16:647. doi: 10.1186/s12885-016-2690-6. PubMed PMID: 27538997.

Diffuse midline glioma H3 K27M-mutant treatment

Diffuse midline glioma H3 K27M-mutant treatment

Stereotactic biopsy is being performed in some centers, and may become routine when therapies specifically targeted to these mutations become available.

Diffuse midline glioma H3 K27M-mutant have no effective treatment, and their location and diffuse nature render them inoperable. Radiation therapy remains the only standard of care for this devastating disease.

Until recently biopsies were considered not informative enough and therefore not recommended.

Systemic administration of chemotherapeutic agents is often hindered by the blood brain barrier (BBB), and even drugs that successfully cross the barrier may suffer from unpredictable distributions. The challenge in treating this deadly disease relies on effective delivery of a therapeutic agent to the bulk tumor as well as infiltrating cells. Therefore, methods that can enhance drug delivery to the brain are of great interest. Convection-enhanced delivery (CED) is a strategy that bypasses the BBB entirely and enhances drug distribution by applying hydraulic pressure to deliver agents directly and evenly into a target region. This technique reliably distributes infusate homogenously through the interstitial space of the target region and achieves high local drug concentrations in the brain. Moreover, recent studies have also shown that continuous delivery of drug over an extended period of time is safe, feasible, and more efficacious than standard single session CED. Therefore, CED represents a promising technique for treating midline tumors with the H3K27M mutation 1).

Based on the molecular heterogeneity observed in this tumor type, personalized treatment is considered to substantially improve therapeutic options. Therefore, clinical evidence for therapy, guided by comprehensive molecular profiling, is urgently required. In this study, we analyzed feasibility and clinical outcomes in a cohort of 12 H3K27M glioma cases treated at two centers. Patients were subjected to personalized treatment either at primary diagnosis or disease progression and received backbone therapy including focal irradiation. Molecular analyses included whole-exome sequencing of tumor and germline DNA, RNA-sequencing, and transcriptomic profiling. Patients were monitored with regular clinical as well as radiological follow-up. In one case, liquid biopsy of cerebrospinal fluid (CSF) was used. Analyses could be completed in 83% (10/12) and subsequent personalized treatment for one or more additional pharmacological therapies could be recommended in 90% (9/10). Personalized treatment included inhibition of the PI3K/AKT/mTOR pathway (3/9), MAPK signaling (2/9), immunotherapy (2/9), receptor tyrosine kinase inhibition (2/9), and retinoic receptor agonist (1/9). The overall response rate within the cohort was 78% (7/9) including one complete remission, three partial responses, and three stable diseases. Sustained responses lasting for 28 to 150 weeks were observed for cases with PIK3CA mutations treated with either miltefosine or everolimus and additional treatment with trametinib/dabrafenib in a case with BRAFV600E mutation. Immune checkpoint inhibitor treatment of a case with increased tumor mutational burden (TMB) resulted in complete remission lasting 40 weeks. Median time to progression was 29 weeks. Median overall survival (OS) in the personalized treatment cohort was 16.5 months. Last, we compared OS to a control cohort (n = 9) showing a median OS of 17.5 months. No significant difference between the cohorts could be detected, but long-term survivors (>2 years) were only present in the personalized treatment cohort. Taken together, we present the first evidence of clinical efficacy and an improved patient outcome through a personalized approach at least in selected cases of H3K27M glioma 2).

Although GD2–CAR T-cells demonstrated significant anti-tumor activity against Diffuse midline glioma H3 K27M-mutant in vivo, a multimodal approach may be needed to more effectively treat patients. de Billy et al. investigated GD2 expression in DMG/DIPG and other pediatric high-grade gliomas (pHGG) and sought to identify chemical compounds that would enhance GD2-CAR T-cell anti-tumor efficacy.

Immunohistochemistry in tumor tissue samples and immunofluorescence in primary patient-derived cell lines were performed to study GD2 expression. We developed a high-throughput cell-based assay to screen 42 kinase inhibitors in combination with GD2-CAR T-cells. Cell viability, western blots, flow-cytometry, real time PCR experiments, DIPG 3D culture models and orthotopic xenograft model were applied to investigate the effect of selected compounds on DIPG cell death and CAR T-cell function.

GD2 was heterogeneously, but widely, expressed in the tissue tested, while its expression was homogeneous and restricted to DMG/DIPG H3K27M-mutant cell lines. We identified dual Insulin-like growth factor 1 receptor( IGF1R/IR) antagonists, BMS-754807 and linsitinib, able to inhibit tumor cell viability at concentrations that do not affect CAR T-cells. Linsitinib, but not BMS-754807, decreases activation/exhaustion of GD2-CAR T-cells and increases their central memory profile. The enhanced anti-tumor activity of linsitinib/GD2-CAR T-cell combination was confirmed in DIPG models in vitro, ex vivo and in vivo.

The study supports the development of IGF1R/IR inhibitors to be used in combination with GD2-CAR T-cells for Diffuse midline glioma H3 K27M-mutant treatment and, potentially, by pHGG 3).

Findings suggest that targeting PLK1 with small-molecule inhibitors, in combination with radiation therapy, will hold a novel strategy in the treatment of Diffuse intrinsic pontine glioma (DIPG) that warrants further investigation 4).

1)

Himes BT, Zhang L, Daniels DJ. Treatment Strategies in Diffuse Midline Gliomas With the H3K27M Mutation: The Role of Convection-Enhanced Delivery in Overcoming Anatomic Challenges. Front Oncol. 2019 Feb 8;9:31. doi: 10.3389/fonc.2019.00031. PMID: 30800634; PMCID: PMC6375835.
2)

Gojo J, Pavelka Z, Zapletalova D, Schmook MT, Mayr L, Madlener S, Kyr M, Vejmelkova K, Smrcka M, Czech T, Dorfer C, Skotakova J, Azizi AA, Chocholous M, Reisinger D, Lastovicka D, Valik D, Haberler C, Peyrl A, Noskova H, Pál K, Jezova M, Veselska R, Kozakova S, Slaby O, Slavc I, Sterba J. Personalized Treatment of H3K27M-Mutant Pediatric Diffuse Gliomas Provides Improved Therapeutic Opportunities. Front Oncol. 2020 Jan 10;9:1436. doi: 10.3389/fonc.2019.01436. PMID: 31998633; PMCID: PMC6965319.
3)

de Billy E, Pellegrino M, Orlando D, Pericoli G, Ferretti R, Businaro P, Ajmone-Cat MA, Rossi S, Petrilli LL, Maestro N, Diomedi-Camassei F, Pezzullo M, De Stefanis C, Bencivenga P, Palma A, Rota R, Del Bufalo F, Massimi L, Weber G, Jones C, Carai A, Caruso S, De Angelis B, Caruana I, Quintarelli C, Mastronuzzi A, Locatelli F, Vinci M. Dual IGF1R/IR inhibitors in combination with GD2-CAR T-cells display a potent anti-tumor activity in diffuse midline glioma H3K27M-mutant. Neuro Oncol. 2021 Dec 29:noab300. doi: 10.1093/neuonc/noab300. Epub ahead of print. PMID: 34964902.
4)

Amani V, Prince EW, Alimova I, Balakrishnan I, Birks D, Donson AM, Harris P, Levy JM, Handler M, Foreman NK, Venkataraman S, Vibhakar R. Polo-like Kinase 1 as a potential therapeutic target in Diffuse Intrinsic Pontine Glioma. BMC Cancer. 2016 Aug 18;16:647. doi: 10.1186/s12885-016-2690-6. PubMed PMID: 27538997.

Low grade glioma outcome

Low grade glioma outcome

Primary or secondary dissemination develops in 5–10 % 1).

Low-grade gliomas are infiltrative tumors that progressively invade the brain tissue by migrating along the subcortical white matter tracts. Contrary to the indolent characteristics claimed by classical literature, there is a constant growth pattern of these tumors before and after surgery in cases of incomplete resection 2).

The result of the study demonstrated that MSR1 is an independent prognostic biomarker in LGG patients and may play an important role in the tumor microenvironment (TME) of LGGs 3).

Patients diagnosed with a low-grade glioma are 17 times as likely to die as matched patients in the general population 4).

The age-standardized 10-year relative survival rate was 47% 5).

One study reported that low-grade oligodendroglioma patients have a median survival of 11.6 years; 6), another reported a median survival of 16.7 years 7).

Low grade glioma (LGG) patients have increased life expectancy, so interest is high in the treatments that maximize cognition and quality of life.

Tumor histology, size and IDH-mutation status are important predictors for prolonged overall survival in patients with LGG and may provide a reliable tool for standardizing future treatment strategies 8).

Health related quality of life

Reports on long-term health related quality of life (HRQL) after surgery for World Health Organization grade II diffuse low-grade gliomas (LGG) are rare.

In two hospital cohorts with different surgical strategies. Biopsy and watchful waiting was favored in one hospital, while early resections guided with three-dimensional (3D) ultrasound was favored in the other. With a population-based approach 153 patients with histologically verified LGG treated from 1998-2009 were included. Patients still alive were contacted for HRQL assessment (n=91) using generic (EQ-5D; EuroQol Group, Rotterdam, The Netherlands) and disease specific (EORTC QLQ-C30 and BN20; EORTC Quality of Life Department, Brussels, Belgium) questionnaires. Results on HRQL were available in 79 patients (87%), 25 from the hospital that favored biopsy and 54 from the hospital that favored early resection. Among living patients there was no difference in EQ-5D index scores (p=0.426). When imputing scores defined as death (zero) in patients dead at follow-up, a clinically relevant difference in EQ-5D score was observed in favor of early resections (p=0.022, mean difference 0.16, 95% confidence interval 0.02-0.29). In EORTC questionnaires pain, depression and concern about disruption in family life were more common with a strategy of initial biopsy only (p=0.043, p=0.032 and p=0.045 respectively).

Although HRQOL remains mostly preserved in the majority of patients with LGG, a subset of patients experience detectable decline on one or more HRQOL scales despite long-term stable disease. For this subgroup, further research is recommended to better aid patients in dealing with the consequences of LGG 9).

In long-term survivors an aggressive surgical approach using intraoperative 3D ultrasound image guidance in LGG does not lower HRQL compared to a more conservative surgical approach. This finding further weakens a possible role for watchful waiting in LGG 10).

Neurocognitive Function

Many patients with low-grade glioma experience cognitive dysfunction. However, there is no consensus on how to assess cognitive functioning in these patients 11).

For 22 patients with newly diagnosed LGG who underwent baseline neuropsychological evaluation and magnetic resonance imaging before awake surgery resection with mapping. Twelve of the 22 patients returned for postoperative evaluation approximately 7 months after surgery.

At baseline, 92% of patients/caregivers reported changes in cognition or mood. Neurological examinations and Montreal Cognitive Assessment Scales were largely normal; however, on many tests of memory and language, nearly half of individuals showed deficits. After surgery, 45% had no deficits on neurological examination, whereas 55% had only transient or mild difficulties. Follow-up neuropsychological testing found most performances stable to improved, particularly in language, although some patients showed declines on memory tasks.

Most LGG patients in this series presented with normal neurological examinations and cognitive screening, but showed subjective cognitive and mood concerns and cognitive decline on neuropsychological testing, suggesting the importance of comprehensive evaluation. After awake mapping, language tended to be preserved, but memory demonstrated decline in some patients. These results highlight the importance of establishing a cognitive baseline before surgical resection and further suggest that awake mapping techniques provide reasonable language outcomes in individuals with LGG in eloquent regions 12).

Sexuality after surgery

Sexual dysfunction is common in this population. Therefore, Surbeck et al. suggest that sexual health should consistently be addressed during routine pre- and postoperative examination of patients with DLGG 13).

References

1)

von Hornstein S, Kortmann RD, Pietsch T et al. Impact of chemo- therapy on disseminated low-grade glioma in children and adolescents: report from the HIT-LGG 1996 trial. Pediatric blood & cancer 2011; 56: 1046–1054
2)

Pallud J, Taillandier L, Capelle L, Fontaine D, Peyre M, Ducray F, et al. Quantitative morphological magnetic resonance imaging follow-up of low-grade glioma: a plea for systematic measurement of growth rates. Neurosurgery. 2012;71:729–739. doi: 10.1227/NEU.0b013e31826213de.
3)

Ji Q, Huang K, Jiang Y, Lei K, Tu Z, Luo H, Zhu X. Comprehensive analysis of the prognostic and role in immune

The results of a study of Qi et al. indicated that a high Neutrophil to lymphocyte ratio was an independent risk factor for overall survival rates in patients with LGG, which may increase prognostic accuracy and improve patient outcomes ((Qi Z, Cai J, Meng X, Cai S, Tang C, Lang L. Prognostic value of preoperative inflammatory markers among different molecular subtypes of lower-grade glioma. J Clin Neurosci. 2021 Nov 18:S0967-5868(21)00513-0. doi: 10.1016/j.jocn.2021.10.006. Epub ahead of print. PMID: 34802893.

4) , 5)

Smoll N, Gautschi OP, Schatlo B, Schaller K, Weber DC (July 6, 2012). “Relative Survival of Patients with Supratentorial Low Grade Gliomas”. Neuro-Oncology.
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Ohgaki H, Kleihues P (June 2005). “Population-based studies on incidence, survival rates, and genetic alterations in astrocytic and oligodendroglial gliomas”
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http://www.neurology.org/cgi/content/abstract/54/7/1442
8)

Tanaka K, Sasayama T, Mizukawa K, Takata K, Sulaiman NS, Nishihara M, Kohta M, Sasaki R, Hirose T, Itoh T, Kohmura E. Combined IDH1 mutation and MGMT methylation status on long-term survival of patients with cerebral low-grade glioma. Clin Neurol Neurosurg. 2015 Jul 31;138:37-44. doi: 10.1016/j.clineuro.2015.07.019. [Epub ahead of print] PubMed PMID: 26276726.
9)

Boele FW, Douw L, Reijneveld JC, Robben R, Taphoorn MJ, Aaronson NK, Heimans JJ, Klein M. Health-related quality of life in stable, long-term survivors of low-grade glioma. J Clin Oncol. 2015 Mar 20;33(9):1023-9. doi: 10.1200/JCO.2014.56.9079. Epub 2015 Feb 9. PubMed PMID: 25667287.
10)

Jakola AS, Unsgård G, Myrmel KS, Kloster R, Torp SH, Sagberg LM, Lindal S, Solheim O. Surgical strategies in low-grade gliomas and implications for long-term quality of life. J Clin Neurosci. 2014 Aug;21(8):1304-9. doi: 10.1016/j.jocn.2013.11.027. Epub 2014 May 3. PubMed PMID: 24798909.
11)

van Loon EM, Heijenbrok-Kal MH, van Loon WS, van den Bent MJ, Vincent AJ, de Koning I, Ribbers GM. Assessment methods and prevalence of cognitive dysfunction in patients with low-grade glioma: A systematic review. J Rehabil Med. 2015 Jun 24;47(6):481-8. doi: 10.2340/16501977-1975. PubMed PMID: 25994416.
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Racine CA, Li J, Molinaro AM, Butowski N, Berger MS. Neurocognitive Function in Newly Diagnosed Low-grade Glioma Patients Undergoing Surgical Resection With Awake Mapping Techniques. Neurosurgery. 2015 Sep;77(3):371-9. doi: 10.1227/NEU.0000000000000779. PubMed PMID: 25930064.
13)

Surbeck W, Herbet G, Duffau H. Sexuality after surgery for diffuse low-grade glioma. Neuro Oncol. 2015 Apr;17(4):574-9. doi: 10.1093/neuonc/nou326. Epub 2015 Feb 19. PubMed PMID: 25699682.

Low-Grade Glioma Radiotherapy Dose

Low-Grade Glioma Radiotherapy Dose

Adjuvant radiation is often used in patients with low-grade gliomas with high-risk characteristics with a recommended dose of 45-54 Gy. Byrne et al. used the National Cancer Database (NCDB) to see which doses were being used and if any difference was seen in outcome.

They queried the NCDB for patients with WHO Grade 2 primary brain tumors treated with surgery and adjuvant radiotherapy. We divided the cohort into dose groups: 45-50 Gy, 50.4-54 Gy, and > 54 Gy. Multivariable logistic regression was used to identify predictors of low and high-dose radiation. Propensity matching was used to account for indication bias.

Results: We identified 1437 patients meeting inclusion criteria. The median age was 45 years and 62% of patients were > 40 years old. Nearly half of patients (48%) had astrocytoma subtype and 70% had a subtotal resection. The majority of patients (69%) were treated to doses between 50.4 and 54 Gy. Predictors of high dose radiation (> 54 Gy) were increased income, astrocytoma subtype, chemotherapy receipt, and treatment in a later years (2014). The main predictors of survival were age > 40, astrocytoma subtype, and insurance type. Patients treated to a dose of > 54 Gy had a median survival of 73.5 months and was not reached in those treated to a lower dose (p = 0.0041).

This analysis showed that 50.4-54 Gy is the most widely used radiation regimen for the adjuvant treatment of low-grade gliomas. There appeared to be no benefit to higher doses, although unreported factors may impact the interpretation of the results 1).

Postoperative policies of “wait-and-see” and radiotherapy for low-grade glioma are poorly defined. A trial in the mid 1980s established the radiation dose.

A phase III prospective randomized trial of low- versus high-dose radiation therapy for adults with supratentorial low-grade astrocytoma, oligodendroglioma, and oligoastrocytoma found somewhat lower survival and slightly higher incidence of radiation necrosis in the high-dose RT arm. The most important prognostic factors for survival are histologic subtype, tumor size, and age 2).

Two prospective trials found no difference in OS or PFS between different XRT doses (EORTC trial 3): 45 Gy in 5 weeks vs. 59.4 Gy in 6.6 weeks; Intergroup study 4) 50.4 vs. 64.8 Gy).

1)

Byrne E, Abel S, Yu A, Shepard M, Karlovits SM, Wegner RE. Trends in radiation dose for low-grade gliomas across the United States. J Neurooncol. 2022 Feb 23. doi: 10.1007/s11060-022-03962-4. Epub ahead of print. PMID: 35199246.
2)

Shaw E, Arusell R, Scheithauer B, O’Fallon J, O’Neill B, Dinapoli R, Nelson D, Earle J, Jones C, Cascino T, Nichols D, Ivnik R, Hellman R, Curran W, Abrams R. Prospective randomized trial of low- versus high-dose radiation therapy in adults with supratentorial low-grade glioma: initial report of a North Central Cancer Treatment Group/Radiation Therapy Oncology Group/Eastern Cooperative Oncology Group study. J Clin Oncol. 2002 May 1;20(9):2267-76. PubMed PMID: 11980997.
3)

Karim ABMF, Maat B, Hatlevoll R, et al. A random- ized trial on dose-response in radiation therapy of low-grade cerebral glioma: European Organization for Research and Treatment of Cancer (EORTC) Study 22844. Int J Radiation Oncology Biol Phys. 1996; 36:549–556
4)

Shaw E, Arusell R, Scheithauer B, O’Fallon J, O’Neill B, Dinapoli R, Nelson D, Earle J, Jones C, Cascino T, Nichols D, Ivnik R, Hellman R, Curran W, Abrams R. Prospective randomized trial of low- versus high-dose radiation therapy in adults with supra- tentorial low-grade glioma: initial report of a North Central Cancer Treatment Group/Radiation Therapy Oncology Group/Eastern Cooperative Oncology Group study. J Clin Oncol. 2002; 20:2267–2276

Diffuse midline glioma H3 K27M-mutant MRI

Diffuse midline glioma H3 K27M-mutant MRI

T1: decreased intensity

T2: heterogeneously increased

T1 C+ (Gd): usually minimal (can enhance post-radiotherapy)

DWI/ADC: usually normal, occasionally mildly restricted

Extensive spread is relatively frequent, both craniocaudally to involve the cerebral hemispheres and spinal cord, as well as leptomeningeal spread 1)

A study included 66 cases (40 in men, 26 in women) of H3 K27M-mutant glioma in adult patients. Tumors were found in the following sites: thalamus (n = 38), brainstem (n = 6), brainstem with cerebellar or thalamic involvement (n = 4), whole-brain (n = 8), corpus callosum (n = 3), hypothalamus (n = 1), hemispheres (n = 2), and spinal cord (n = 4). All pure brainstem lesions were located posteriorly, and all corpus callosal lesions were in the genu. Most spinal tumors were long-segment lesions. Hemispheric lesions mimicked gliomatosis cerebri in presentation, with the addition of traditional midline structure involvement. Most tumors were solid with relatively uniform signals on plain MRI. Of the 61 cases with contrast-enhanced MR images, 36 (59%) showed partial to no enhancement, whereas 25 (41%) showed diffuse or irregular peripheral enhancement. Hemorrhage and edema were rare. Most lesions were solid and showed mild diffusion restriction on diffusion-weighted imaging. Tumor dissemination to the leptomeninges (n = 8) and subependymal layer (n = 3) was observed.

Qiu et al. described the MRI features of diffuse midline glioma with H3 K27M mutation in the largest study done to date in adult patients. Tumors were found in both midline and nonmidline structures, with the thalamus being the most common site. Although adult H3 K27M-mutant gliomas demonstrated highly variable presentations in this cohort of patients, the authors were able to observe shared characteristics within each location 2).

The radiographic features of diffuse midline gliomas with histone H3 K27M mutation were highly variable, ranging from expansile masses without enhancement or necrosis with large areas of surrounding infiltrative growth to peripherally enhancing masses with central necrosis with the significant mass effect but little surrounding T2/FLAIR hyperintensity. When we compared diffuse midline gliomas on the basis of the presence or absence of histone H3 K27M mutation, there was no significant correlation between enhancement or border characteristics, infiltrative appearance, or presence of edema 3)

Zhuo et al. from the Beijing Tiantan Hospital aimed to predict H3K27M mutation status by Amide proton transfer imaging (APTw) and radiomic features.

Methods: Eighty-one BSG patients with APTw imaging at 3T MR and known H3K27M status were retrospectively studied. APTw values (mean, median, and max) and radiomic features within manually delineated 3D tumor masks were extracted. Comparison of APTw measures between H3K27M-mutant and wildtype groups was conducted by two-sample Student’s T/Mann-Whitney U test and receiver operating characteristic curve (ROC) analysis. H3K27M-mutant prediction using APTw-derived radiomics was conducted using a machine learning algorithm (support vector machine) in randomly selected train (n = 64) and test (n = 17) sets. Sensitivity analysis with additional random splits of train and test sets, 2D tumor masks, and other classifiers were conducted. Finally, a prospective cohort including 29 BSG patients was acquired for validation of the radiomics algorithm.

Results: BSG patients with H3K27M-mutant were younger and had higher max APTw values than those with wildtype. APTw-derived radiomic measures reflecting tumor heterogeneity could predict H3K27M mutation status with an accuracy of 0.88, the sensitivity of 0.92, and specificity of 0.80 in the test set. Sensitivity analysis confirmed the predictive ability (accuracy range: 0.71-0.94). In the independent prospective validation cohort, the algorithm reached an accuracy of 0.86, the sensitivity of 0.88, and specificity of 0.85 for predicting H3K27M-mutation status.

Conclusion: BSG patients with H3K27M-mutant had higher max APTw values than those with wildtype. APTw-derived radiomics could accurately predict an H3K27M-mutant status in BSG patients 4).

Piccardo et al., from Genoa, retrospectively analyzed 22 pediatric patients with DMG histologically proved and molecularly classified as H3K27M-mutant (12 subjects) and wild-type (10 subjects) who underwent DWI, Proton magnetic resonance spectroscopic imaging, and ASL performed within 2 weeks of 18F-FDOPA PET. DWI-derived relative minimum apparent diffusion coefficient (rADC min), 1H-MRS data choline/N-acetylaspartate (Cho/NAA), choline/creatine (Cho/Cr), and presence of lactate and relative ASL-derived cerebral blood flow max (rCBF max) were compared with 18F-DOPA uptake Tumor/Normal tissue (T/N) and Tumor/Striatum (T/S) ratios, and correlated with histological and molecular features of DMG. Statistics included Pearson’s chi-squared test and Mann-Whitney U tests, Spearman’s rank correlation and receiver operating characteristic (ROC) analysis.

The highest degrees of correlation among different techniques were found between T/S, rADC min and Cho/NAA ratio (p < 0.01), and between rCBF max and rADC min (p < 0.01). Significant differences between histologically classified low- and high-grade DMG, independently of H3K27M-mutation, were found among all imaging techniques (p ≤ 0.02). Significant differences in terms of rCBF max, rADC min, Cho/NAA and 18F-DOPA uptake were also found between molecularly classified mutant and wild-type DMG (p ≤ 0.02), even though wild-type DMG included low-grade astrocytomas, not present among mutant DMG. When comparing only histologically defined high-grade mutant and wild-type DMG, only the 18F-DOPA PET data T/S demonstrated statistically significant differences independently of histology (p < 0.003). ROC analysis demonstrated that T/S ratio was the best parameter for differentiating mutant from wild-type DMG (AUC 0.94, p < 0.001).

Advanced MRI and 18F-DOPA PET characteristics of DMG depend on histological features; however, 18F-DOPA PET-T/S was the only parameter able to discriminate H3K27M-mutant from wild-type DMG independently of histology 5).

References

1)

Louis DN, Ohgaki H, Wiestler OD, Cavenee WK, Burger PC, Jouvet A, Scheithauer BW, Kleihues P. The 2007 WHO classification of tumours of the central nervous system. Acta Neuropathol. 2007 Aug;114(2):97-109. doi: 10.1007/s00401-007-0243-4. Epub 2007 Jul 6. Erratum in: Acta Neuropathol. 2007 Nov;114(5):547. PMID: 17618441; PMCID: PMC1929165.
2)

Qiu T, Chanchotisatien A, Qin Z, Wu J, Du Z, Zhang X, Gong F, Yao Z, Chu S. Imaging characteristics of adult H3 K27M-mutant gliomas. J Neurosurg. 2019 Nov 15:1-9. doi: 10.3171/2019.9.JNS191920. Epub ahead of print. PMID: 31731269.
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Aboian MS, Solomon DA, Felton E, Mabray MC, Villanueva-Meyer JE, Mueller S, Cha S. Imaging Characteristics of Pediatric Diffuse Midline Gliomas with Histone H3 K27M Mutation. AJNR Am J Neuroradiol. 2017 Apr;38(4):795-800. doi: 10.3174/ajnr.A5076. Epub 2017 Feb 9. PMID: 28183840; PMCID: PMC5394943.
4)

Zhuo Z, Qu L, Zhang P, Duan Y, Cheng D, Xu X, Sun T, Ding J, Xie C, Liu X, Haller S, Barkhof F, Zhang L, Liu Y. Prediction of H3K27M-mutant brainstem glioma by amide proton transfer-weighted imaging and its derived radiomics. Eur J Nucl Med Mol Imaging. 2021 Jun 16. doi: 10.1007/s00259-021-05455-4. Epub ahead of print. PMID: 34131804.
5)

Piccardo A, Tortora D, Mascelli S, Severino M, Piatelli G, Consales A, Pescetto M, Biassoni V, Schiavello E, Massollo M, Verrico A, Milanaccio C, Garrè ML, Rossi A, Morana G. Advanced MR imaging and (18)F-DOPA PET characteristics of H3K27M-mutant and wild-type pediatric diffuse midline gliomas. Eur J Nucl Med Mol Imaging. 2019 Apr 27. doi: 10.1007/s00259-019-04333-4. [Epub ahead of print] PubMed PMID: 31030232.

Intraoperative direct electrocortical stimulation for glioma surgery

see also Awake surgery for glioma.

see also Resting-state functional magnetic resonance for glioma surgery.

Stimulation-induced seizures (SISs) are rare but serious events during electrocortical stimulation (ECS) mapping. SISs are most common when mapping the frontal lobe. Greater stimulation current is not associated with the identification of more cortical functional sites during glioma surgery 1).

Glioma surgery represents a significant advance with respect to improving resection rates using new surgical techniques, including intraoperative functional mapping, monitoring, and imaging. Functional mapping under awake craniotomy can be used to detect individual eloquent tissues of speech and/or motor functions in order to prevent unexpected deficits and promote extensive resection. In addition, monitoring the patient’s neurological findings during resection is also very useful for maximizing the removal rate and minimizing deficits by alarming that the touched area is close to eloquent regions and fibers. Assessing several types of evoked potentials, including motor evoked potentials (MEPs), sensory evoked potentials (SEPs), and visual evoked potentials (VEPs), is also helpful for performing surgical monitoring in patients under general anesthesia (GA) 2).

The greater extent of resection (EOR) of low-grade gliomas is associated with improved survival. Proximity to eloquent cortical regions often limits resectability and elevates the risk of surgery-related deficits. Therefore, functional localization of eloquent cortex or subcortical fiber tracts can enhance the EOR and functional outcome. Imaging techniques such as functional MRI and diffusion tensor imaging fiber tracking, and neurophysiological methods like navigated transcranial magnetic stimulation and magnetoencephalography, make it possible to identify eloquent areas prior to resective surgery and to tailor indication and surgical approach but also to assess the surgical risk. Intraoperative monitoring with direct cortical stimulation and subcortical stimulation enables surgeons to preserve essential functional tissue during surgery. Through tailored, pre-and intraoperative mapping and monitoring the EOR can be maximized, with reduced rates of surgery-related deficits 3).

As the most accurate and reliable method of brain functional area positioning, Intraoperative direct electrocortical stimulation is able to determine in real-time the parts of the brain necessary for such functions as movement, sensation, language, and even memory. A meta-analysis suggested that it could also improve the degree of resection of glioma while reducing the incidence of permanent neurological dysfunction 4).

Findings suggest that surgeons using Intraoperative direct electrocortical stimulation and awake craniotomy during their resections of high-grade glioma in eloquent areas experienced better surgical outcomes: a significantly longer overall postoperative survival, a lower rate of postoperative complications, and a higher percentage of GTR 5).

Resting-state functional magnetic resonance imaging likely reflects similar neural information as detected with intraoperative direct electrocortical stimulation (DES), but in its current form does not reach the spatial resolution of DES. 6).

References

1)

Muster RH, Young JS, Woo PYM, Morshed RA, Warrier G, Kakaizada S, Molinaro AM, Berger MS, Hervey-Jumper SL. The Relationship Between Stimulation Current and Functional Site Localization During Brain Mapping. Neurosurgery. 2021 May 13;88(6):1043-1050. doi: 10.1093/neuros/nyaa364. PMID: 33289525; PMCID: PMC8117445.
2)

Saito T, Muragaki Y, Maruyama T, Tamura M, Nitta M, Okada Y. Intraoperative Functional Mapping and Monitoring during Glioma Surgery. Neurol Med Chir (Tokyo). 2015;55 Suppl 1:1-13. PMID: 26236798.
3)

Ottenhausen M, Krieg SM, Meyer B, Ringel F. Functional preoperative and intraoperative mapping and monitoring: increasing safety and efficacy in glioma surgery. Neurosurg Focus. 2015 Jan;38(1):E3. doi: 10.3171/2014.10.FOCUS14611. PMID: 25552283.
4)

De Witt Hamer PC, Robles SG, Zwinderman AH, Duffau H, Berger MS. Impact of intraoperative stimulation brain mapping on glioma surgery outcome: a meta-analysis. J Clin Oncol. 2012;30:2559–2565. doi: 10.1200/JCO.2011.38.4818.
5)

Gerritsen JKW, Arends L, Klimek M, Dirven CMF, Vincent AJE. Impact of intraoperative stimulation mapping on high-grade glioma surgery outcome: a meta-analysis. Acta Neurochir (Wien). 2019 Jan;161(1):99-107. doi: 10.1007/s00701-018-3732-4. Epub 2018 Nov 21. PMID: 30465276; PMCID: PMC6331492.
6)

van Lieshout J, Debaene W, Rapp M, Noordmans HJ, Rutten GJ. fMRI Resting-State Connectivity between Language and Nonlanguage Areas as Defined by Intraoperative Electrocortical Stimulation in Low-Grade Glioma Patients. J Neurol Surg A Cent Eur Neurosurg. 2021 Feb 22. doi: 10.1055/s-0040-1721757. Epub ahead of print. PMID: 33618418.