scholarly journals LGG-50. INTEGRATED MOLECULAR AND CLINICAL ANALYSIS OF 1,000 PEDIATRIC LOW-GRADE GLIOMAS UNCOVERS NOVEL SUBGROUPS FOR CLINICAL RISK STRATIFICATION

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii375-iii376
Author(s):  
Uri Tabori ◽  
Scott Ryall ◽  
Michal Zapotocky ◽  
Julie Bennett ◽  
Liana Nobre ◽  
...  
Keyword(s):  
Risk Stratification ◽  
Clinical Presentation ◽  
Mapk Pathway ◽  
Clinical Analysis ◽  
Genetic Alterations ◽  
Low Grade ◽  
Who Grade ◽  
Low Grade Gliomas ◽  
Younger Age ◽  
Risk Categories

Abstract Pediatric low-grade gliomas (pLGG) are primarily driven by genetic alterations in the RAS/MAPK pathway, most commonly involving BRAF of NF1. Despite their molecular convergence, pLGG often show unexplained variability in their clinical outcome. To address this, we molecularly characterized a cohort of >1,000 clinically annotated pLGG. 84% of cases harbored a detectable driver mutation. The remaining 16% of patients nonetheless showed RAS/MAPK pathway up-regulation at the RNA level. The clinical presentation and outcome of pLGG appeared highly variable and linked to the alteration type: re-arrangement or SNV. Re-arrangement-driven tumors were diagnosed at a younger age (6.6 versus 10.9 years, p<0.0001), enriched for WHO grade I histology (88% versus 66%, p<0.0001), infrequently progressed (27% versus 46%, p<0.0001), and rarely resulted in death (3 versus 13%, p<0.0001) as compared to SNV-driven tumors. These included the rarest molecular drivers of pLGG, for which we now have the clinicopathologic features of including MYB, MYBL1, FGFR2 fusions, FGFR1-TACC1, FGFR1 SNVs, IDH1 p.R132H, and H3.3 p.K27M. Utilizing this information, we suggest novel risk categories of pLGG that effectively predicted patient outcome. Low-risk tumors progressed infrequently and rarely succumbed to their disease (10-year PFS of 71% and OS of 98%). Intermediate-risk pLGG had a 10-year PFS and OS of 35% and 90%, respectively. High risk pLGG almost invariably progressed (10-year PFS of 0%) and these patients often succumbed to their disease (10-year OS of 41%). These data highlight the biological and clinical differences between pLGG subtypes and offers molecular based risk stratification to these cancers.

scholarly journals LGG-06. COMPREHENSIVE GENOMIC CHARACTERIZATION AND INTEGRATED CLINICAL ANALYSIS OF LOW-GRADE GLIOMAS IN CHILDREN WITH NEUROFIBROMATOSIS TYPE 1

2021 ◽  
Vol 23 (Supplement_1) ◽  
pp. i32-i32
Author(s):  
Michael Fisher ◽  
David Jones ◽  
Yimei Li ◽  
Xiaofan Guo ◽  
Poonam Sonawane ◽  
...  
Keyword(s):  
Neurofibromatosis Type 1 ◽  
Pik3ca Mutation ◽  
Neurofibromatosis Type ◽  
Clinical Analysis ◽  
Genetic Alterations ◽  
Low Grade ◽  
Low Grade Gliomas ◽  
Fgfr1 Mutation ◽  
Glioneuronal Tumors

Abstract Background Low-grade gliomas (LGGs) arising in children with neurofibromatosis type 1 (NF1) are usually not biopsied. To identify secondary genetic alterations or molecular features that may contribute to pathogenesis and correlate with clinical behavior, we initiated a comprehensive molecular and clinical analysis of pediatric NF1-LGGs. Methods NF1-LGGs were analysed by whole-genome sequencing (31), targeted gene panel sequencing (9), RNAseq transcriptomal profiling (33) and genome-wide DNA methylation analysis (67). Clinical annotation was available for 48 subjects. Results Most LGGs harbored bi-allelic NF1 inactivation as the sole genetic abnormality, but 11% had additional alterations (FGFR1 mutation, n=3; PIK3CA mutation, n=2; homozygous 9p21 deletion, n=2; MYB:QKI fusion, n=1; SETD2 mutation, n=1; EGFR amplification, n=1). FGFR1 mutation conferred additional growth advantage in multiple complementary murine Nf1 models. 88% of NF1-LGGs resembled sporadic pilocytic astrocytoma (PA) by methylation, higher than that based on histology. Non-PA methylation patterns included low-grade glial/glioneuronal tumors, rosette-forming glioneuronal tumors, MYB/MYBL1-altered glioma, and high-grade astrocytoma with piloid features (2 tumors histologically diagnosed as LGG). In total, 18% of samples were classified as non-PA and/or harbored an additional non-NF1 mutation. Non-PA methylation class tumors were more likely to harbor an additional non-NF1 mutation (p=0.005). 7.7% of optic pathway hypothalamic gliomas (OPHGs) had other mutations or were not classified by methylation as PA, compared with 20.6% of NF1-LGGs arising elsewhere. There was no difference based on age for the presence of an additional non-NF1 mutation or non-PA methylation class. Conclusions Given the overall low occurrence of non-NF1 mutations or non-PA methylation class tumors in this series, routine clinical biopsy of typically-appearing NF1-LGG may not be indicated, particularly for children with OPHG. Biopsy should be considered for non-OPHG tumors refractory to conventional treatment. As additional agents are developed and treatment strategies evolve, the rationale for biopsy of NF1-LGG may become stronger.

scholarly journals Association of the FGFR1 mutation with spontaneous hemorrhage in low-grade gliomas in pediatric and young adult patients

2020 ◽  
pp. 1-9 ◽  
Author(s):  
Yukitomo Ishi ◽  
Shigeru Yamaguchi ◽  
Kanako C. Hatanaka ◽  
Michinari Okamoto ◽  
Hiroaki Motegi ◽  
...  
Keyword(s):  
Young Adult ◽  
Univariate Analysis ◽  
Genetic Alterations ◽  
Adult Patients ◽  
World Health ◽  
Low Grade ◽  
Diffuse Astrocytoma ◽  
Who Grade ◽  
Low Grade Gliomas ◽  
Spontaneous Hemorrhage

OBJECTIVEThe authors aimed to investigate genetic alterations in low-grade gliomas (LGGs) in pediatric and young adult patients presenting with spontaneous hemorrhage.METHODSPatients younger than 30 years of age with a pathological diagnosis of World Health Organization (WHO) grade I or II glioma and who had undergone treatment at the authors’ institution were retrospectively examined. BRAF V600E, FGFR1 N546/K656, IDH1 R132, IDH2 R172, and KIAA1549-BRAF (K-B) fusion genetic alterations were identified, and the presence of spontaneous tumoral hemorrhage was recorded.RESULTSAmong 66 patients (39 with WHO grade I and 27 with grade II tumors), genetic analysis revealed K-B fusion in 18 (27.3%), BRAF V600E mutation in 14 (21.2%), IDH1/2 mutation in 8 (12.1%), and FGFR1 mutation in 4 (6.1%). Spontaneous hemorrhage was observed in 5 patients (7.6%); 4 of them had an FGFR1 mutation and 1 had K-B fusion. Univariate analysis revealed a statistically significant association of an FGFR1 mutation and a diencephalic location with spontaneous hemorrhage. Among 19 diencephalic cases including the optic pathway, hypothalamus, and thalamus, an FGFR1 mutation was significantly associated with spontaneous hemorrhage (p < 0.001). Four FGFR1 mutation cases illustrated the following results: 1) a 2-year-old female with pilomyxoid astrocytoma (PMA) harboring the FGFR1 K656E mutation presented with intraventricular hemorrhage (IVH); 2) a 6-year-old male with PMA harboring FGFR1 K656E and D652G mutations presented with intratumoral hemorrhage (ITH); 3) a 4-year-old female with diffuse astrocytoma harboring FGFR1 K656M and D652G mutations presented with IVH; and 4) a young adult patient with pilocytic astrocytoma with the FGFR1 N546K mutation presented with delayed ITH and IVH after 7 years of observation.CONCLUSIONSAlthough the mechanism remains unclear, the FGFR1 mutation is associated with spontaneous hemorrhage in pediatric and young adult LGG.

scholarly journals LGG-02. PEDIATRIC LOW-GRADE GLIOMA RISK STRATIFICATION IN THE MOLECULAR ERA

2021 ◽  
Vol 23 (Supplement_1) ◽  
pp. i31-i31
Author(s):  
Jessica Hata ◽  
Mustafa Barbour ◽  
Michael Angelo Huang
Keyword(s):  
Risk Factors ◽  
Risk Stratification ◽  
Mapk Pathway ◽  
Risk Classification ◽  
Low Risk ◽  
Braf V600e ◽  
Subtotal Resection ◽  
Low Grade ◽  
Who Grade ◽  
The Impact

Abstract Background Pediatric low-grade gliomas (LGG), in particular those not amenable to surgical resection, are a therapeutic challenge owing to their heterogeneity in clinical behavior. Identification of the RAS/MAPK pathway as a universal feature of these tumors has led to an improved understanding and the development of targeted therapeutics. We examined the impact of known biological and novel molecular risk factors on patient outcomes at our institution. Methods We retrospectively reviewed risk factors and clinical outcomes in 38 LGG cases diagnosed by histopathology at Norton Children’s Hospital in Louisville, KY, USA from March 2015 to Jan 2019. Progression free survival (PFS) rates were generated using the Kaplan-Meier method. Log-rank tests and hazard ratios were used to identify prognostic factors by univariable analysis. Results Among previously described biological risk factors, subtotal resection/biopsy only (HR 3.67, p=0.0257), non-WHO Grade I histology (HR 3.34, p=0.0101), and infant age (&lt; 3 years) (HR 4.19, p=0.0031) were associated with shorter PFS. Brainstem location had no significant impact on PFS. (HR 0.86, p=0.8071). H3K27M mutant status was predictably associated with worse PFS (HR 5.86, p=0.0012). BRAF v600e mutant status, however, was not associated with inferior outcomes. On the contrary, in our study population, BRAF v600e mutant status had a suggested protective effect (HR 0.14, p=0.0247). Patients with 2 or more oncogenic driver mutations demonstrated worsened PFS (HR 4.78, p=0.0059). We utilized the following scoring system for risk stratification: 1 point was allocated for each of the above biological and molecular risk factors except for H3K27M, which was allocated 3 points. A score of &lt; 3 was designated low risk. Non-low risk classification was associated with significantly inferior PFS (median PFS 13 vs. 62 mos, HR 4.26, p=0.0012). Conclusion We herein demonstrate the utility of a combined biological and molecular risk classification for pediatric LGG.

scholarly journals LGG-18. EVEROLIMUS TREATMENT IN PEDIATRIC PATIENTS AFFECTED BY LOW-GRADE GLIOMAS (pLGG) NON-TSC, BRAF v600-WT

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii369-iii369
Author(s):  
Antonella Cacchione ◽  
Evelina Miele ◽  
Maria Chiara Lodi ◽  
Andrea Carai ◽  
Giovanna Stefania Colafati ◽  
...  
Keyword(s):  
Adverse Event ◽  
Disease Progression ◽  
Mapk Pathway ◽  
Brain Mri ◽  
Mammalian Target Of Rapamycin ◽  
Low Grade ◽  
Duration Of Treatment ◽  
Tumor Biopsy ◽  
Low Grade Gliomas ◽  
Personalized Approach

Abstract BACKGROUND MAPK pathway is the hallmark of pediatric low grade gliomas (pLGGs); hyperactivation of mTOR (mammalian target of rapamycin) might be a suitable biomarker for therapeutic response. We investigated the feasibility of Everolimus, mTOR inhibitor, in patients affected by pLGGs. METHODS Patients 1 to 18 years old, diagnosed with pLGG, with a positive tumor biopsy for mTOR/phospho-mTOR and radiological and / or clinical disease progression, treated at Bambino Gesù Children’s Hospital in Rome were evaluated. Tumor DNA methylation analysis was performed in 10 cases. Exclusion criteria included: Tuberous Sclerosis patients, Sub Ependymal Giant Astrocytoma. Everolimus was administered orally at a dose of 2.5 mg or 5 mg daily based on body weight. Patients were evaluated with brain MRI every 4, 8 and 12 months after treatment start and every six months thereafter. RESULTS 16 patients were enrolled from September 2014 and 2019. The median age was 7.5 years old. All patients had at least one adverse event. Events rated as severe (grade 3/4) were reported in 6 patients. Stomatitis was the most frequent adverse event. One patient discontinued treatment due to grade 4 toxicity (ulcerative stomatitis and fatigue). The median duration of treatment was 21 months (4–57 months). Brain MRI evaluations have showed disease stability in 11 patients, partial response in 2 patients and disease progression in 3 patients. CONCLUSIONS Everolimus has proven to be well tolerated and effective treatment in terms of disease stability in patients with pLGGs. It’s also an excellent example of chemo-free personalized approach.

scholarly journals LGG-31. CHARACTERIZING TEMPORAL GENOMIC HETEROGENEITY IN PEDIATRIC LOW GRADE GLIOMAS: ANALYSIS OF AN EXPANDED MULTI-INSTITUTIONAL COHORT WITH 101 PAIRED TUMOR SAMPLES

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii372-iii372
Author(s):  
Margot A Lazow ◽  
Austin Schafer ◽  
Mariko D DeWire-Schottmiller ◽  
Adam Lane ◽  
Daniel R Boué ◽  
...  
Keyword(s):  
Genetic Alterations ◽  
Rapid Progression ◽  
Low Grade ◽  
Valuable Insight ◽  
Histologic Diagnosis ◽  
Low Grade Gliomas ◽  
Genomic Landscape ◽  
Cdkn2a Deletion ◽  
Diagnostic Biopsy ◽  
Over Time

Abstract INTRODUCTION Recent discoveries have provided valuable insight into the genomic landscape of pediatric low grade gliomas (LGGs) at diagnosis, facilitating molecularly targeted treatment. However, little is known about their temporal and therapy-related genomic heterogeneity. An adequate understanding of the evolution of pediatric LGGs’ genomic profiles over time is critically important in guiding decisions about targeted therapeutics and diagnostic biopsy at recurrence. METHODS Fluorescence in situ hybridization, mutation-specific immunohistochemistry, and exome analyses were performed on paired tumor samples from primary diagnostic and subsequent surgeries. RESULTS 101 tumor samples from 48 patients (43 with 2 specimens, 5 with 3 specimens) from 3 institutions underwent testing. BRAF fusion and BRAFV600E status were conserved in 100% and 97% of paired specimens, respectively. No loss or gain of IDH1 mutations or FGFR1, NTRK2, MYB, or MYBL1 rearrangements were detected over time. Histologic diagnosis remained the same in all tumors, with no acquired H3K27M mutations or malignant transformation. CDKN2A deletions were acquired in 7 patients (including 3 who received chemotherapy [2 with temozolomide] and 1 who received radiation), and were associated with a trend toward shorter time to progression (median: 5.5 vs. 13.0 months [p=0.08]). CONCLUSIONS Most targetable genetic alterations in pediatric LGGs, including BRAF alterations, are conserved at recurrence and following chemotherapy or radiation. However, CDKN2A deletion acquisition was demonstrated and may define a higher risk group. Given potential for targeted therapies for tumors acquiring CDKN2A deletions, performing a biopsy at recurrence may be indicated in certain patients, especially those with rapid progression.

scholarly journals The Role of Extent of Resection in IDH1 Wild-Type or Mutant Low-Grade Gliomas

Neurosurgery ◽  
2017 ◽  
Vol 82 (6) ◽  
pp. 808-814 ◽  
Author(s):  
Toral Patel ◽  
Evan D Bander ◽  
Rachael A Venn ◽  
Tiffany Powell ◽  
Gustav Young-Min Cederquist ◽  
...  
Keyword(s):  
Cox Regression ◽  
Extent Of Resection ◽  
World Health ◽  
Low Grade ◽  
Wild Type ◽  
Who Grade ◽  
Cox Regression Analysis ◽  
Low Grade Gliomas ◽  
Grade Ii ◽  
The Impact

Abstract BACKGROUND Maximizing extent of resection (EOR) improves outcomes in adults with World Health Organization (WHO) grade II low-grade gliomas (LGG). However, recent studies demonstrate that LGGs bearing a mutation in the isocitrate dehydrogenase 1 (IDH1) gene are a distinct molecular and clinical entity. It remains unclear whether maximizing EOR confers an equivalent clinical benefit in IDH mutated (mtIDH) and IDH wild-type (wtIDH) LGGs. OBJECTIVE To assess the impact of EOR on malignant progression-free survival (MPFS) and overall survival (OS) in mtIDH and wtIDH LGGs. METHODS We performed a retrospective review of 74 patients with WHO grade II gliomas and known IDH mutational status undergoing resection at a single institution. EOR was assessed with quantitative 3-dimensional volumetric analysis. The effect of predictor variables on MPFS and OS was analyzed with Cox regression models and the Kaplan–Meier method. RESULTS Fifty-two (70%) mtIDH patients and 22 (30%) wtIDH patients were included. Median preoperative tumor volume was 37.4 cm3; median EOR of 57.6% was achieved. Univariate Cox regression analysis confirmed EOR as a prognostic factor for the entire cohort. However, stratifying by IDH status demonstrates that greater EOR independently prolonged MPFS and OS for wtIDH patients (hazard ratio [HR] = 0.002 [95% confidence interval {CI} 0.000-0.074] and HR = 0.001 [95% CI 0.00-0.108], respectively), but not for mtIDH patients (HR = 0.84 [95% CI 0.17-4.13] and HR = 2.99 [95% CI 0.15-61.66], respectively). CONCLUSION Increasing EOR confers oncologic and survival benefits in IDH1 wtLGGs, but the impact on IDH1 mtLGGs requires further study.

Use of DNA copy number analysis of grade 2-4 gliomas to reveal differences in molecular ontogeny associated with IDH mutation status.

2013 ◽  
Vol 31 (15_suppl) ◽  
pp. 2026-2026
Author(s):  
Mariko Sato ◽  
Kenneth D. Aldape ◽  
Clinton C Mason ◽  
Kristin Diefes ◽  
Lindsey Heathcock ◽  
...  
Keyword(s):  
Copy Number ◽  
Genetic Alterations ◽  
Idh1 Mutation ◽  
Low Grade ◽  
Copy Number Alterations ◽  
Copy Number Analysis ◽  
Mutation Status ◽  
Younger Age ◽  
Ffpe Samples ◽  
Molecular Inversion Probes

2026 Background: The genetic alterations of glioma have been studied extensively. IDH1 mutation is associated with younger age and better survival. However, differences in molecular ontogeny within glioma related to IDH1 mutation remain unknown. Here we describe a detailed analysis of copy number alterations (CNA) between IDH1mut vs IDH1wt gliomas of grade 2-3 and 4. Methods: CNA were detected by molecular inversion probes (Affymetrix) and analyzed with Nexus Copy Number Software (BioDiscovery). DNA was extracted from 94 patient FFPE samples including grade 2-3: IDH1wt (n = 17) and IDH1mut (n = 28), and grade IV: IDH1wt ( n = 25) and IDH1mut(n = 24). Chromothripsis was detected using a stringent criteria of at least ten switches of CNA in individual chromosomes. Results: We validated prior findings that IDH1wt GBM have higher frequency of Chr7 amplification (including EGFR) and loss of Chr10 (including PTEN). Other CNA across all grades were: gain of 19q12 and loss of 14q11 in IDH1wt, and gain of 11q21, 10p11, 8q21 and loss of 11p15, 19q13 in IDH1mut. Within grade 2-3 samples, few CNA were associated with mutation status: 2-3wt demonstrated higher frequencies of gain of 7q and loss of 10q, 14q11, and 22q13, while 2-3mut demonstrated higher frequencies of 11q21 gain and 19q13 loss. Grade 4 tumors demonstrated more CNA that differed by mutation status, with 4wt tumors demonstrating gain of 7 and loss of 10 and 14q11, while 4mut demonstrated gains of 8q, 10p, 12p13, 1q23, and loss of 11p15, 3p, 19q13, among others. Comparison of grade 2-3mut vs grade 4mut tumors demonstrated larger number of CNA in the grade 4mut tumors including gain of 1p, 14q, 13q33, 9p, 8q and loss of 22q, 11p15, 10q, and 3p, among others. A significantly higher incidence of chromothripsis events was observed in grade 4mut compared to grade 4wt (p = 0.0374). Conclusions: CNA analysis showed significant differences in molecular ontogeny between IDH1wt and IDH1mut, some of which may further elucidate pathogenesis. Significant CNA increases and increased chromthripsis in grade 4mut support malignant transformation of low grade gliomas through accumulation of genomic instability and genomic catastrophe.

Efficacy of Fractionated Stereotactic Reirradiation in Recurrent Gliomas: Long-Term Results in 172 Patients Treated in a Single Institution

2005 ◽  
Vol 23 (34) ◽  
pp. 8863-8869 ◽  
Author(s):  
Stephanie E. Combs ◽  
Christoph Thilmann ◽  
Lutz Edler ◽  
Jürgen Debus ◽  
Daniela Schulz-Ertner
Keyword(s):  
Overall Survival ◽  
Progression Free Survival ◽  
Primary Diagnosis ◽  
Long Term Results ◽  
Low Grade ◽  
Single Institution ◽  
Who Grade ◽  
Low Grade Gliomas ◽  
Recurrent Gliomas ◽  
Grade 3

Purpose To evaluate the efficacy of fractionated stereotactic radiotherapy (FSRT) performed as reirradiation in 172 patients with recurrent low- and high-grade gliomas. Patients and Methods Between 1990 and 2004, 172 patients with recurrent gliomas were treated with FSRT as reirradiation in a single institution. Seventy-one patients suffered from WHO grade 2 gliomas. WHO grade 3 gliomas were diagnosed in 42 patients, and 59 patients were diagnosed with glioblastoma multiforme (GBM). The median time between primary radiotherapy and reirradiation was 10 months for GBM, 32 months for WHO grade 3 tumors, and 48 months for grade 2 astrocytomas. FSRT was performed with a median dose of 36 Gy in a median fractionation of 5 × 2 Gy/wk. Results Median overall survival after primary diagnosis was 21 months for patients with GBM, 50 months for patients with WHO grade 3 gliomas, and 111 months for patients with WHO grade 2 gliomas. Histologic grading was the strongest predictor for overall survival, together with the extent of neurosurgical resection and age at primary diagnosis. Median survival after reirradiation was 8 months for patients with GBM, 16 months for patients with grade 3 tumors, and 22 months for patients with low-grade gliomas. Only time to progression and histology were significant in influencing survival after reirradiation. Progression-free survival after FSRT was 5 months for GBM, 8 months for WHO grade 3 tumors, and 12 months for low-grade gliomas. Conclusion FSRT is well tolerated and may be effective in patients with recurrent gliomas. Prospective studies are warranted for further evaluation.

Interstitial radiosurgery of low-grade gliomas

1995 ◽  
Vol 82 (3) ◽  
pp. 418-429 ◽  
Author(s):  
Friedrich W. Kreth ◽  
Michael Faist ◽  
Peter C. Warnke ◽  
Reinhard Roβner ◽  
Benedikt Volk ◽  
...  
Keyword(s):  
Ct Scan ◽  
Tumor Recurrence ◽  
Survival Rates ◽  
Low Grade ◽  
Who Grade ◽  
Content Type ◽  
Low Grade Gliomas ◽  
Interstitial Radiosurgery ◽  
Grade Ii ◽  
Fine Print

✓ The treatment of patients with low-grade gliomas remains a subject of controversy, especially with respect to new treatment modalities such as interstitial radiosurgery (brachytherapy), radiosurgery, and stereotactic radiotherapy. In a retrospective analysis conducted between 1979 and 1991, the authors studied the results of interstitial radiosurgery in 455 patients with low-grade gliomas (World Health Organization (WHO) Grade I + WHO Grade II) with regard to survival time, quality of life, the risk of malignant transformation, and the risk profile of the treatment concept. Interstitial radiosurgery with iodine-125 was performed using permanent (1979–1985) or temporary implants (after 1985) with low-dose rates (≤ 10 cGy/hr) and a reference dose of 60 to 100 Gy calculated to the outer rim of the tumor. The 5- and 10-year survival rates in patients with pilocytic astrocytomas (97 patients) were 84.9% and 83%, and in patients with WHO Grade II astrocytomas (250 patients) 61% and 51%, respectively. Five-year survival rates for patients with oligoastrocytomas (60 patients), oligodendrogliomas (27 patients), and gemistocytic astrocytomas (21 patients) were 49%, 50%, and 32%, respectively. In the group with WHO Grade II gliomas, young age and a good performance status were associated with a better prognosis. Unfavorable factors were midline shift, enhancement on computerized tomography (CT) scan, and tumor recurrence after previous radiotherapy or surgery. Tumor location had no influence on the prognosis (247 patients in this series had deep-seated tumors). Malignant transformation was the major cause of death. Important risk factors for malignancy were the patient's age, tumor enhancement in CT scan, and tumor recurrence after previous surgery or radiotherapy. Perioperative mortality was 0.9% and perioperative morbidity was 1.7%. Radiogenic complications were observed in 2.7% of all patients, most often in larger tumors and after using permanent implants. The authors conclude that interstitial radiosurgery represents a specific treatment modality for selected patients with unifocal circumscribed low-grade gliomas with a diameter of less than 4 cm in any location. The efficacy of this treatment lies in the same range as the best results after surgery and radiotherapy.

Sign in / Sign up

Export Citation Format

Share Document