Treatment Of Low-grade Gliomas Research Articles

Low-grade gliomas in adults

Making treatment decisions for patients with infiltrating low-grade gliomas (LGGs) is challenging. Patients frequently present with seizures and usually have little or no neurologic deficit. In this younger and relatively well patient population, despite the potential for significant morbidity, we believe that surgical resection, radiation therapy, and chemotherapy each play an important role in the optimal management of these tumors. Randomized clinical trials have begun to address some of the many questions about prognosis, natural history, and treatment, but most questions have yet to be answered. We believe that, when possible, a maximal surgical resection consistent with preservation of neurologic function should be performed, even though it is likely that no randomized clinical trial will ever be done to demonstrate a survival advantage for this approach. External beam radiation therapy is most often given to a total dose of 50.4 or 54 Gy in 1.8-Gy fractions. The role of chemotherapy is less certain, but a growing body of evidence suggests that temozolomide, a generally well-tolerated drug, is active in the treatment of LGGs. In recent years, loss of heterozygosity of chromosome 1p and 19q, as well as silencing of the MGMT gene, have been identified as promising predictors of response to adjuvant therapy in gliomas. Although randomized trials have not yet shown a survival benefit for early radiation therapy or chemotherapy, one study by the European Organisation for Research and Treatment of Cancer did show an improvement in time to tumor progression with the earlier use of radiation therapy. In addition, a trial by the Radiation Therapy Oncology Group (soon to be analyzed and reported) is comparing radiation alone with radiation followed by a year (six cycles) of standard-dose PCV chemotherapy (procarbazine, CCNU, and vincristine); this trial may shed light on the use of chemotherapy in conjunction with radiation therapy for the initial treatment of LGGs. Because patients remain at risk for tumor progression for the remainder of their lives, we recommend lifelong follow-up with MRI scans, even for patients without documented tumor regrowth over long intervals. To give clinicians a more solid basis for guiding therapy recommendations, we encourage participation in large cooperative group clinical trials.

Neurodevelopmental outcomes of children with low‐grade gliomas

As a group, children with low-grade gliomas (LGGs) enjoy a high rate of long-term survival and do not require the intensity of neurotoxic treatments used with higher risk pediatric brain tumors. Because they are generally considered to have favorable neurobehavioral outcomes, they have not been studied as thoroughly as higher-grade brain tumors by late-effects researchers. In this article, we review the literature on the neurobehavioral effects associated with low-grade gliomas and conclude that, (1) this is a large, understudied group of survivors of pediatric brain tumors; (2) recent small- and large-scale studies document increased risk in multiple cognitive-behavioral domains after treatment for LGGs compared with healthy peers; (3) such risk is not uniform but varies with tumor location and treatments; and (4) a life span development perspective is essential to a complete understanding of the risks faced by these children. More research on the most efficacious biopsychosocial treatment models for improving the outcomes of survivors of low-grade glioma is recommended, informed by a better understanding of theireducational needs. Investigations of genetic influences on outcome as well as prospective studies of these patients as they age are also recommended.

Toxicity and efficacy of protracted low dose temozolomide for the treatment of low grade gliomas

Protracted low dose temozolomide (75 mg/m(2)/day on days 1-21 of 28 days) offers potential advantages over standard temozolomide schedules (200 mg/m(2)/day on days 1-5 of 28 days) including greater cumulative drug exposure and depletion of O(6)-alkylguanine DNA alkyltransferase levels, theoretically overcoming intrinsic chemoresistance. We retrospectively review our experience in 25 patients with pathologically proven low grade gliomas (LGG) treated with protracted low dose temozolomide to primarily quantify its toxicity and secondarily to assess efficacy. None had previously received radiation. Tumor response was graded based on changes in tumor size, steroid requirements, and clinical exam. About 243 cycles of protracted low dose temozolomide were administered. Three patients (12%) were changed to standard temozolomide dosing due to side effects, including intractable nausea (n = 2) and multiple cytopenias (n = 1). The most frequent toxicities were fatigue (76%), lymphopenia (72% [48% high grade]), constipation (56%), and nausea (52%). High grade toxicities (other than lymphopenia) included secondary malignancy, pruritus, hyponatremia, neutropenia, leukopenia, and cognitive decline (n = 1 for each). Tumor response rate was 52% and and disease control rate was 84%. Six month PFS was 92% and 12 month PFS was 72%. Response rates and PFS were independent of pathological subtype, deletion status, and indication for chemotherapy. Protracted low dose temozolomide has a distinct spectrum of toxicities compared to standard dosing but is well tolerated in most patients and may provide improved response rates compared to standard dosing. The results of larger randomized trials are needed to assess its potential advantages over other management schemes.

Cognitive functions in low-grade gliomas: disease and treatment effects

The role of radiotherapy and chemotherapy in the treatment of low-grade gliomas (LGG) is controversial regarding their effect on survival and the development of neurotoxicity. The few published studies examining adverse treatment effects on cognition revealed conflicting results. To assess cognitive functioning in LGG patients who received conformal radiation therapy (RT), chemotherapy, or no treatment. 40 LGG patients participated in the study; 16 patients had RT +/- chemotherapy, and 24 patients had no treatment. All patients underwent a neuropsychological evaluation. APOE genotype was obtained in 36 patients who were classified in two groups based on the presence or absence of at least one apolipoprotein E small je, Ukrainian-4 (APOE small je, Ukrainian-4) allele. Treated LGG patients had lower scores than untreated patients on several cognitive domains; patients who completed treatment at intervals greater than 3 years and had long disease duration had significantly lower scores on the Non-Verbal Memory domain. Antiepileptic polytherapy, treatment history, and disease duration jointly contributed to low Psychomotor domain scores. 62% of treated patients showed white matter confluence on MRI, whereas only 9% of the untreated patients had such changes. Preliminary comparisons between APOE small je, Ukrainian-4 carriers (n = 9) and non-carriers (n = 27) on cognitive domain scores revealed no statistically significant differences, but APOE small je, Ukrainian-4 carriers had lower mean scores on the Verbal Memory domain than did non-small je, Ukrainian-4 carriers. RT +/- chemotherapy, disease duration, and antiepileptic treatment contributed to mild cognitive difficulties in LGG patients.

Effectiveness of novel combination chemotherapy, consisting of 5-fluorouracil, vincristine, cyclophosphamide and etoposide, in the treatment of low-grade gliomas in children

Low-grade gliomas (LGG), which account for about 30% of brain tumors in children, are usually treated with surgical excision and/or radiotherapy. For patients who have significant residual tumor after resection or relapse after radiation, the proper chemotherapy regimen has not yet been identified. Thirteen children diagnosed with LGG outside the cerebellum between January 1999 and December 2004, all of whom had significant residual tumor after surgical resection, relapsed after radiation or showed visual deterioration, were treated for 18 months with a multi-drug regimen of vincristine, etoposide, cyclophosphamide and 5-fluorouracil. Of the 7 patients who completed chemotherapy, 1 showed complete response (CR), 5 showed partial response (PR), and 1 had stable disease (SD). In 5 patients, chemotherapy was prematurely discontinued; 4 of these patients showed tumor progression and 1 had SD. One patient is still undergoing treatment. The side effects of chemotherapy were manageable. The median time to tumor response was 34 months (range, 2-82 months). The progression free survival was 67.3%. Pediatric LGG patients with residual tumor after surgery or who undergo relapse(s) may be successfully treated using our combination chemotherapy regimen.

Carboplatin hypersensitivity reaction in pediatric low grade glioma (LGG) patients: A national experience. On behalf of the Canadian Pediatric Brain Tumor Consortium

9053 Background: Carboplatin based regimens are widely used in the treatment of unresectable pediatric LGG. Carboplatin hypersensitivity reaction (CHSR) represents a main limiting factor. Objective: To analyse the incidence, characteristics, management and impact on outcome of CHSR. Methods: National retrospective review of children diagnosed with LGG between 1988 and 2004. Inclusion criteria were age <18 years, pathology proven diagnosis of LGG except in NF1 patients, and no chemotherapy or radiotherapy prior to carboplatin chemotherapy. Results: 105 patients (61F/44M) from 10 Canadian centers were included in the study. Median age at diagnosis was 3.5y (0.3–16.8). 33 patients had NF1, 75 had diencephalic tumor. Carboplatin was given monthly or weekly respectively in 46 and 59 patients. 44 (41.9%) patients developed carboplatin HSR at a median time of 6.5 months (0.4–15.4), after a median number of 10.5 (3–39) injections. CHSR occurred significantly earlier with the weekly schedule (p=0.016). Cumulative incidence of CHSR increased with the number of injections with no plateau. Female had significant higher risk to develop CHSR (p=0.02) whereas age, NF1 status and schedule of administration were not significant risk factors. First allergic reaction was rated grade I, II in 36 patients (82%). 34 patients were reexposed to carboplatin with desensitization/premedication, allowing 14 patients (41.2%) to complete their treatment. But the majority (58.8%) had recurrent allergic reaction with a significant worsening of their symptoms (p=0.039). The median number of additional Carboplatin injections delivered was 4 (0.5–34). After Carboplatin discontinuation, 18 patients were switched to another chemotherapy regimen. 5 years PFS was not significantly different in allergic and non allergic patients (53.9% and 45.6%). Conclusions: In our experience, the incidence of CHSR is high (41.9%). Female have higher risk of CHSR. Desensitization/premedication has limited efficacy and does not prevent worsening of CHSR. CHSR did not impact the PFS. However many patients did switch to another chemotherapy regimen and the total duration of treatment was comparable in both groups. No significant financial relationships to disclose.

Initial report of Radiation Therapy Oncology Group (RTOG) 9802: Prospective studies in adult low-grade glioma (LGG)

1500 Background: Treatment of adult LGG is controversial. Favorable patients (pts) (age <40 years [yrs] who undergo gross total resection [GTR]) are typically observed. Unfavorable pts (age ≥40 who have subtotal resection [STR] or biopsy [B]) are usually given initial radiation therapy (RT), reserving chemotherapy (historically procarbazine, CCNU and vincristine [PCV]) for recurrence. In 1998, the RTOG, in conjunction with SWOG, NCCTG, and ECOG initiated prospective studies of adult LGG, the results of which are reported herein. Methods: Favorable pts were observed postoperatively in a single arm Phase II study (Arm 1). Unfavorable pts were stratified by age, histology, KPS, and presence/absence of contrast enhancement on preoperative magnetic resonance imaging and randomized to either RT alone (54Gy in 30 fractions to a local treatment field) (Arm 2) or RT followed by 6 cycles of standard dose PCV (Arm 3). Reported results include overall survival (OS) rate, median overall survival time (MOST), progression-free survival (PFS) rate, and median progression-free survival time (MPFST). Survival data are compared using Wilcoxon p-values. Results: A total of 362 eligible/analyzable pts were accrued between 1998 and 2002. Median follow-up time is 4 years. For the 111 favorable pts observed on Arm 1, OS at 2- and 5-yrs is 99% and 94%. PFS at 2- and 5-yrs is 82% and 50%. For the 251 unfavorable pts on Arms 2 (RT alone) and 3 (RT+PCV), there was no difference in OS or PFS. OS at 2- and 5-yrs was 87% and 61% with RT alone versus (vs) 86% and 70% with RT+PCV (p=0.72). MOST was not reached in RT alone pts and was 6.0 yrs in RT+PCV pts. PFS at 2- and 5-yrs was 73% and 39% with RT alone vs 72% and 61% with RT+PCV (p=0.38). MPFST was 4.0 yrs with RT alone vs 6.0 yrs with RT+PCV. Acute grade 3–4 toxicity occurred in 9% of pts who received RT alone, 67% who received RT+PCV (mostly hematologic). There were no treatment deaths on either arm. Conclusions: 5-yr PFS was poor in all three arms ranging from 39% to 61%. Only half of favorable pts were disease-free at 5 yrs. In unfavorable pts, there was no OS advantage with the addition of PCV to RT. Both PFS and MPFST were better with the addition of PCV, but not significantly. Analysis of outcome by 1p19q status is pending. No significant financial relationships to disclose.

Diffusely Infiltrative Low-Grade Gliomas in Adults

Diffusely infiltrating low-grade gliomas (LGGs) include astrocytomas, oligodendrogliomas, and mixed oligoastrocytomas (WHO grade 2). Due to the routine use of magnetic resonance imaging, there is an increasing need to formulate treatment guidelines for patients with LGGs. However, there is little consensus about the optimal treatment strategy for diffusely infiltrative LGGs, and the clinical management of LGGs is one of the most controversial areas in neurooncology. Although the standard of care has not been established, several randomized trials are beginning to provide some answers. Furthermore, laboratory correlative studies are defining subsets of LGG that may identify patients with better prognoses and increased chance of responding to therapy. This article reviews the most recent data regarding the treatment of LGG, emphasizing evidenced based approaches from current clinical trials.

Are gliomas preventable?

Gliomas are a family of primary central nervous system tumors of variable malignancy that are derived from supporting glia (astrocytes, oligodendrocytes, ependymal cells) or their progenitors/stem cells. There are two potential strategies to prevention: preventing gliomas from forming and preventing lower-grade gliomas from developing into higher-grade gliomas. Each would lower time-dependent mortality. Each also depends on an understanding of what causes gliomas so that these factors can be modulated. In this presentation, I will discuss primary prevention, chemoprevention, and screening. I will first focus on the known chromosomal, genetic, and protein changes associated with the different histologic varieties of glioma and the environmental, hereditary, and infectious/viral factors that may promote glioma development and malignant progression. I will discuss a number of clinical scenarios that eventuate from the known genetic patterns of these tumors and the changes in genetic patterns that reflect malignant progression. The basic thinking is that if one could prevent specific gene mutations and/or deletions or gains of specific chromosomes that lead to the development of low-grade (WHO 2) gliomas, then theoretically this would reduce the occurrence of high-grade (WHO 3 and 4) gliomas and hence the almost certain death that now is the fate of most patients with these tumors. In the case of de novo WHO 3 and 4 tumors, being able to prevent or counter specific gene mutations and/or the deletion of specific chromosomes would in itself reduce the occurrence of these gliomas and increase survival. Alternatively, a curative treatment for low-grade glioma that prevents these chromosomal/gene changes would prevent some glioblastomas (WHO 4) from forming and would have the same desired effect on survival. Obviously, for the latter to be achieved, we must also be able to diagnose and treat low-grade gliomas earlier.

Prognosis Analysis of Low Grade Gliomas

Objective To identify prognostic factors in low grade gliomas. Methods To retro-analysis the clinical factors of 98 cases low grade gliomas. Results Age is a prognosis factor for survival in low grade gliomas and a man owns worse prognosis when one is older than forty;Epilepsy is related to a better outcome if this is the only symptom present;Tumor volume greater than 20cm 3 who is of unfavorable prognostic significance;The role of extent of surgical removal remains one of the most controversial issues in the treatment of low grade gliomas. Conclusion The age and clinical manifestation and tumor volume influence prognosis of low grade gliomas.

Weekly vinblastine in pediatric low‐grade glioma patients with carboplatin allergic reaction

Carboplatin-based regimens have demonstrated activity in unresectable low-grade glioma (LGG) in children. Despite an interesting toxicity profile, the use of these regimens has been limited by the development of carboplatin hypersensitivity reaction (HSR) in up to 30% of patients. Desensitization has been the recommended approach for HSR. However, no guidelines have existed to aid physicians when carboplatin desensitization techniques fail. A pilot study of monotherapy with weekly vinblastine for LGG in 9 children who developed carboplatin HSR on a carboplatin and vincristine regimen was performed. Vinblastine toxicity was moderate and readily manageable. None of the 9 patients had disease progression on therapy. Magnetic resonance imaging evaluation of tumor size from diagnosis to the end of vinblastine treatment showed 1 complete response (CR), 1 partial response (PR), 5 objective effects (OE), and 2 stable diseases (SD). This experience suggested that weekly vinblastine has a good efficacy to toxicity ratio in the treatment of LGG and can be a valuable option for children who develop severe HSR.

Temozolomide in the treatment of progressive low-grade glioma

8525 Background: The optimal treatment for low-grade glioma is still controversial. Temozolomide has been shown to be active in gliomas. The goals of this study are to determine the efficacy and si...

72 poster Gamma Knife radiosurgery for the treatment of low grade gliomas : integration of the metabolic data of positron emission tomography (PET) in the dosimetry planning

72 poster Gamma Knife radiosurgery for the treatment of low grade gliomas : integration of the metabolic data of positron emission tomography (PET) in the dosimetry planning

Surgical removal of corpus callosum infiltrated by low-grade glioma: functional outcome and oncological considerations.

Although still controversial, many authors currently advocate extensive resection in the treatment of low-grade gliomas (LGGs). Because these tumors usually migrate along white matter pathways, the corpus callosum is often invaded. Nevertheless, there is evidently no specific study featuring resection of the corpus callosum infiltrated by glioma, despite abundant literature concerning callosotomy in epilepsy surgery or transcallosal ventricular approaches. The aim of this paper was to analyze functional outcome following removal of corpus callosum invaded by LGG and to analyze the impact of this callosectomy on the quality of resection. Between 1996 and 2002, a total of 32 patients harboring an LGG involving part of the corpus callosum and having no or only a mild preoperative deficit underwent surgery aided by intraoperative electrical mapping to preserve eloquent structures identified on stimulation and to perform the most extensive resection possible. Preoperatively, no clinical response was elicited on stimulation of the corpus callosum; thus, the part of this structure that was invaded by LGG was removed. Despite immediate postoperative neurological worsening, all patients but one recovered within 3 months and returned to a normal socioprofessional life. The additional callosectomy allowed for nine total resections, 18 subtotal resections, and five partial resections. Furthermore, only two cases of contralateral hemispherical migration occurred during a median follow up of 3 years. Resection of the corpus callosum infiltrated by glioma improves the quality of tumor removal without increasing the risk of sequelae.

Can chemotherapy replace radiotherapy in low-grade gliomas? Time for randomized studies

For the last three decades surgery and radiotherapy have been the mainstay of treatment for patients with low-grade gliomas, despite a lack of support from randomized controlled trials. Recent developments in our knowledge of low-grade tumor chemosensitivity and the approval of temozolomide for treatment of gliomas have led to increased interest in chemotherapy for treating low-grade gliomas. Despite challenges, including response assessment and appropriate patient selection, several phase II studies investigating chemotherapeutic treatment of low-grade gliomas have yielded promising results. Although most of these phase II studies are of limited sample size, they have shown that chemotherapy might induce clinically relevant responses and disease stabilization in patients with low-grade gliomas. As expected, low-grade oligodendroglioma is sensitive to chemotherapy, but responses were also seen in astrocytic tumors. Randomized, controlled studies should be conducted to determine the clinical significance of responses observed in phase II studies and to assess time to progression. Two randomized, controlled studies are currently investigating chemotherapy in the treatment of low-grade gliomas. Although it will take years before the data are available, these studies will help define the role of chemotherapy in the treatment of low-grade gliomas. Perhaps then we can answer the question, can chemotherapy replace radiotherapy in low-grade gliomas?

Neurocognitive sequelae in the treatment of low-grade gliomas

Patients with low-grade gliomas may live without disease progression for many years after initial diagnosis and treatment, but long-term cognitive deficits, which affect up to 90% of patients, can have a sustained negative effect on their daily functioning and quality of life. Cognitive deficits in patients with low-grade gliomas may be caused by the tumor itself or by various other factors including tumor-related epilepsy, tumor treatment (surgery, radiotherapy [RT], medical therapy [including chemotherapy]), psychological stress, or a combination of these. Although some studies suggest a strong link between RT and neurocognitive sequelae, other studies have found little evidence that RT is a major risk factor for cognitive deficits and suggest that other factors may play a major role. The results of a recent cross-sectional study involving 195 patients with low-grade gliomas (104 of whom received RT) strongly suggest that standard focal RT with fractional doses less than 2 Gy is not generally associated with an increased risk of cognitive deficits, but that higher fractional doses are likely to result in cognitive disability. Notably, the presence and severity of epileptic seizures and/or the use of antiepileptic drugs were more strongly associated with cognitive deficits than was RT. This and other studies suggest that disease and treatment factors other than standard focal RT may be more important with respect to increasing the risk of neurocognitive sequelae in patients with low-grade gliomas.

Temozolomide chemotherapy for progressive low-grade glioma: clinical benefits and radiological response

BackgroundThe optimal treatment for low-grade glioma (LGG) is still controversial. Recent data indicate a potential influence of chemotherapy on the natural evolution of these tumors, allowing for the deferral of more aggressive therapies. Patients and methodsForty-three patients affected with LGG (29 astrocytoma, four oligodendroglioma and 10 mixed oligo-astrocytoma) were treated with temozolomide (TMZ) at the time of documented clinical and radiological progression. McDonald’s response criteria were utilized to evaluate TMZ activity. Thirty patients (69.7%) had previously received radiotherapy; 16 (37.2%) had received prior chemotherapy. Clinical benefit was evaluated measuring seizure control, reduction in steroid dose and modification of Karnofsky performance status and Barthel index. Quality of life was assessed with the QLQ-C30 questionnaire. ResultsWe observed a complete response in four patients, 16 partial responses, 17 stable disease (with four minor response) and six progressive disease. Median duration of response was 10 months [95% confidence interval (CI) 8–12], with a 76% rate of progression free survival (PFS) at 6 months, and a 39% rate of PFS at 12 months. A relevant clinical benefit was observed particularly in patients presenting epilepsy. ConclusionsThe high response rate of 47% (95% CI 31% to 61%) confirms that TMZ chemotherapy is a valid option in the treatment of progressive LGG. The present preliminary results seem interesting and warrant further evaluation of TMZ clinical activity in a larger series of progressive LGG.

Radiotherapy in low-grade gliomas: cons

Although postoperative radiotherapy (RT) is widely used in patients with low-grade gliomas (LGGs), its clinical benefit remains unproven. Because LGGs include diseases with many different histologies, cytogenetic patterns, and natural histories, evaluating the effect of any treatment for LGGs is difficult. Analysis of prognostic subgroups has shown median survival rates ranging from 1 to 10 years. The clinical benefit of postoperative RT in LGGs in retrospective studies is confounded by the heterogeneity of LGGs and treatment-related variables. These studies report conflicting results, most likely because of differences in patient populations. The only prospective, randomized trial comparing postoperative RT with observation failed to show a survival benefit but showed a modest, although statistically significant, improvement in time to progression. Given that two thirds of patients in the observation group received RT at progression, the absence of a survival benefit suggests that RT is active in LGGs, but that delayed RT may provide the same survival advantage as postoperative RT. Moreover, high-dose or whole-brain RT can cause cognitive deficits. Our opinion is that postoperative RT should not be administered routinely to patients with LGGs. If RT is deemed necessary, such as in progressive or inoperable disease causing neurologic symptoms, a total dose of ≤50 Gy with a fractional dose of ≤1.8 to 2 Gy should be administered using modern, highly conformal techniques. Ideally, RT should be used only within the context of clinical research protocols.

A radioterapia nos gliomas supratentoriais de baixo grau de malignidade.

The management of the supratentorial low-grade gliomas has been a question of great debate in our days and the best therapeutic approach is still to determinate. The improvements in the modern surgical techniques have made feasible greater degrees of resection and have lead to longterm progression-free survival remaining surgery as the mainstay of treatment for low grade gliomas. A considerable proportion of patients will have less than complete removal or unresectable tumors and will need more efficacious treatment alternatives which must be identified. This article reviews the current state of knowledge concerning external radiation therapy with regard to the results of recent series, the side effects and potential benefits with newer radiotherapy techniques and provides recommendations with regard to management.

The role of radiotherapy in the management of low grade glioma of the visual pathway in children

Background: Treatment of low grade glioma of the visual pathway in children poses a challenge to the neuro-ophthalmologist and radio-oncologist owing to their low incidence and the lack of consensus about ‘optimal’ treatments. Objectives: To define the role of radiotherapy in present and future treatment approaches. Methods: Reports in the literature spanning 60 years of radiation therapy, including orthovoltage, megavoltage, and recent modern high-precision treatment techniques, were reviewed with respect to the impact on visual function, survival, treatment techniques, and consequences of treatment. Based on these experiences, future strategies in the management of childhood low grade glioma are discussed. Results: Although the efficacy of radiation therapy has been well known for more than 60 years, there are still many open questions. Location and extent of disease often precludes aggressive surgery and a conservative approach is used today with the aim of preserving visual function. Evaluation of published reports is difficult because of short follow-up periods and the failure to present findings and results in a comparable way. Even with the shortcomings of the reports available in the literature primarily concerning indications, dose-response effects, timing, and use of ‘optimal’ treatment fields, fractionated radiation therapy plays an important role in the management of low grade gliomas. Improved or stable visual function is obtained in approximately 90% of the cases. With doses of 45-54 Gy with standard fractionation and limited treatment fields, high local tumor control in up to 80% and more can be achieved. Past series comprising children younger than 5 years of age, however, have reported high rates of severe late effects when using large treatment fields and inadequate fractionation schemes. There is consent today to employ radiotherapy in progressive disease only and that newer technologies, such as 3D treatment planning (conformal radiotherapy), should be used. Recent experiences have achieved promising initial outcome, while reducing treatment-induced toxicity. Stereotactic techniques using high single doses are of minor importance. Conclusions: Radiation therapy is an effective treatment modality with regard to tumor control and improvement and/or preservation of vision. Presently, it is recommended that radiotherapy be initiated in progressive disease in older children and that chemotherapy be given to younger children. More prospective studies are needed (such as the forthcoming study of the International Society for Paediatric Oncology (SIOP-LGG RT 2000) to address the impact of modern radiation therapy technologies on the outcome, including consequences, of treatment.