Interstitial brachytherapy for low-grade cerebral gliomas: analysis of results in a series of 36 cases

Seizure Outcome After Surgery for Insular High-Grade Glioma

BACKGROUND

The insular cortex is an eloquent island of mesocortex surrounded by vital structures making this region relatively challenging to neurosurgeons. Historically, lesions in this region were considered too high risk to approach given the strong chance of poor surgical outcome. Advances in recent decades have meant that surgeons can more safely access this eloquent region. Seizure outcome after excision of insular low-grade gliomas is well reported, but little is known about seizure outcomes after excision of insular high-grade gliomas.

METHODS

A retrospective analysis was performed of all patients presenting with new-onset seizures during 2015-2019 who underwent excision of an insular high-grade glioma at 3 regional neurosurgical centers in the United Kingdom.

RESULTS

We identified 38 patients with a mean (SD) age of 45.7 (15.3) years with median follow-up of 21 months. At long-term follow-up, of 38 patients, 23 were seizure-free (Engel class I), 2 had improved seizures (Engel class II), 6 had poor seizure control (Engel class III/IV), and 7 died.

CONCLUSIONS

Excision of insular high-grade gliomas is safe and results in excellent postoperative seizure control.

An overview of anti-epileptic therapy management of patients with malignant tumors of the brain undergoing radiation therapy

As our surgical, radiation, chemotherapeutic and supportive therapies for brain malignancies improve, and overall survival is prolonged, appropriate symptom management in this patient population becomes increasingly important. This review summarizes the published literature and current practice patterns regarding prophylactic and perioperative anti-epileptic drug use. As a wide range of anti-epileptic drugs is now available to providers, evidence guiding appropriate anticonvulsant choice is reviewed. A particular focus of this article is radiation therapy for brain malignancies. Toxicities and seizure risk associated with cranial irradiation will be discussed. Epilepsy management in patients undergoing radiation for gliomas, glioblastoma multiforme, and brain metastases will be addressed. An emerging but inconsistent body of evidence, reviewed here, indicates that anti-epileptic medications may increase radiosensitivity, and therefore improve clinical outcomes, specifically in glioblastoma multiforme patients.

Seizure response to temozolomide chemotherapy in patients with WHO grade II oligodendroglioma: a single-institution descriptive study

Background

Tumor-related epilepsy (TRE) is common in patients with low-grade oligodendrogliomas. TRE is difficult to control despite multiple antiepileptic drugs (AEDs) in up to 30% of patients. Chemotherapy has been used for treatment to avoid potential radiotherapy-related neurotoxicity. This study evaluates the effect of temozolomide on seizure frequency in a homogeneous group with World Health Organization (WHO) grade II oligodendrogliomas.

Methods

A retrospective analysis was conducted of adult patients with WHO grade II oligodendrogliomas and TRE followed at Memorial Sloan Kettering between 2005 and 2015 who were treated with temozolomide alone either as initial treatment or for disease progression. All had seizures 3 months prior to starting temozolomide. Seizure frequency was reviewed every 2 cycles and at the end of temozolomide treatment. Seizure reduction of ≥50% compared to baseline was defined as improvement.

Results

Thirty-nine individuals met inclusion criteria. Median follow-up since starting temozolomide was 6 years (0.8-13 years). Reduction in seizure frequency occurred in 35 patients (89.7%). Improvement was independent of AED regimen adjustments or prior antitumor treatment in 16 (41%); of these, AED dosage was successfully reduced or completely eliminated in 10 (25.6%). Twenty-five patients (64.1%) remained on a stable AED regimen. The majority (n = 32, 82%) had radiographically stable disease, 5 (12.8%) had objective radiographic response, and 2 (5.2%) had disease progression.

Conclusions

Temozolomide may result in reduced seizure frequency, and permit discontinuation of AEDs in patients with WHO II oligodendroglioma. Improvement was observed irrespective of objective tumor response on MRI, emphasizing the importance of incorporating seizure control in assessing response to tumor-directed therapy.

Glioma-related seizures in relation to histopathological subtypes: a report from the glioma international case-control study

BACKGROUND

The purpose of this study was to evaluate the distribution of glioma-related seizures and seizure control at the time of tumor diagnosis with respect to tumor histologic subtypes, tumor treatment and patient characteristics, and to compare seizure history preceding tumor diagnosis (or study enrollment) between glioma patients and healthy controls.

METHODS

The Glioma International Case Control study (GICC) risk factor questionnaire collected information on demographics, past medical/medication history, and occupational history. Cases from eight centers were also asked detailed questions on seizures in relation to glioma diagnosis; cases (n = 4533) and controls (n = 4171) were also asked about seizures less than 2 years from diagnosis and previous seizure history more than 2 years prior to tumor diagnosis, including childhood seizures.

RESULTS

Low-grade gliomas (LGGs), particularly oligodendrogliomas/oligoastrocytomas, had the highest proportion of glioma-related seizures. Patients with low-grade astrocytoma demonstrated the most medically refractory seizures. A total of 83% of patients were using only one antiepileptic drug (AED), which was levetiracetam in 71% of cases. Gross total resection was strongly associated with reduced seizure frequency (p < 0.009). No significant difference was found between glioma cases and controls in terms of seizure occurring more than 2 years before diagnosis or during childhood.

CONCLUSIONS

Our study showed that glioma-related seizures were most common in low-grade gliomas. Gross total resection was associated with lower seizure frequency. Additionally, having a history of childhood seizures is not a risk factor ***for developing glioma-related seizures or glioma.

Epilepsy and brain tumors

Seizures are common in patients with brain tumors, and epilepsy can significantly impact patient quality of life. Therefore, a thorough understanding of rates and predictors of seizures, and the likelihood of seizure freedom after resection, is critical in the treatment of brain tumors. Among all tumor types, seizures are most common with glioneuronal tumors (70-80%), particularly in patients with frontotemporal or insular lesions. Seizures are also common in individuals with glioma, with the highest rates of epilepsy (60-75%) observed in patients with low-grade gliomas located in superficial cortical or insular regions. Approximately 20-50% of patients with meningioma and 20-35% of those with brain metastases also suffer from seizures. After tumor resection, approximately 60-90% are rendered seizure-free, with most favorable seizure outcomes seen in individuals with glioneuronal tumors. Gross total resection, earlier surgical therapy, and a lack of generalized seizures are common predictors of a favorable seizure outcome. With regard to anticonvulsant medication selection, evidence-based guidelines for the treatment of focal epilepsy should be followed, and individual patient factors should also be considered, including patient age, sex, organ dysfunction, comorbidity, or cotherapy. As concomitant chemotherapy commonly forms an essential part of glioma treatment, enzyme-inducing anticonvulsants should be avoided when possible. Seizure freedom is the ultimate goal in the treatment of brain tumor patients with epilepsy, given the adverse effects of seizures on quality of life.

The role of radiotherapy in the management of patients with diffuse low grade glioma: A systematic review and evidence-based clinical practice guideline

QUESTIONS

(1) What is the optimal role of external beam radiotherapy in the management of adult patients with newly diagnosed low-grade glioma (LGG) in terms of improving outcome (i.e., survival, complications, seizure control or other reported outcomes of interest)? (2) Which radiation strategies (dose, timing, fractionation, stereotactic radiation, brachytherapy, chemotherapy) improve outcomes compared to standard external beam radiation therapy in the initial management of low grade gliomas in adults? (3) Do specific factors (e.g., age, volume, extent of resection, genetic subtype) identify subgroups with better outcomes following radiation therapy than the general population of adults with newly diagnosed low-grade gliomas?

TARGET POPULATION

These recommendations apply to adults with newly diagnosed diffuse LGG.

RECOMMENDATIONS

OUTCOMES IN ADULT PATIENTS WITH NEWLY DIAGNOSED LOW GRADE GLIOMA TREATED WITH RADIOTHERAPY: Level I Radiotherapy is recommended in the management of newly diagnosed low-grade glioma in adults to prolong progression free survival, irrespective of extent of resection. Level II Radiotherapy is recommended in the management of newly diagnosed low grade glioma in adults as an equivalent alternative to observation in preserving cognitive function, irrespective of extent of resection. Level III Radiotherapy is recommended in the management of newly diagnosed low grade glioma in adults to improve seizure control in patients with epilepsy and subtotal resection. Level III Radiotherapy is recommended in the management of newly diagnosed low-grade glioma in adults to prolong overall survival in patients with subtotal resection. Level III Consideration of the risk of radiation induced morbidity, including cognitive decline, imaging abnormalities, metabolic dysfunction and malignant transformation, is recommended when the delivery of radiotherapy is selected in the management of newly diagnosed low-grade glioma in adults. STRATEGIES OF RADIOTHERAPY IN ADULT PATIENTS WITH NEWLY DIAGNOSED LOW GRADE GLIOMA: Level I Lower dose radiotherapy is recommended as an equivalent alternative to higher dose immediate postoperative radiotherapy (45-50.4 vs. 59.4-64.8 Gy) in the management of newly diagnosed low-grade glioma in adults with reduced toxicity. Level III Delaying radiotherapy until recurrence or progression is recommended as an equivalent alternative to immediate postoperative radiotherapy in the management of newly diagnosed low-grade glioma in adults but may result in shorter time to progression. Level III The addition of chemotherapy to radiotherapy is not recommended over whole brain radiotherapy alone in the management of low-grade glioma, as it provides no additional survival benefit. Level III Limited-field radiotherapy is recommended over whole brain radiotherapy in the management of low-grade glioma. Level III Either stereotactic radiosurgery or brachytherapy are recommended as acceptable alternatives to external radiotherapy in selected patients. PROGNOSTIC FACTORS IN ADULT PATIENTS WITH NEWLY DIAGNOSED LOW GRADE GLIOMA TREATED WITH RADIOTHERAPY: Level II It is recommended that age greater than 40 years, astrocytic pathology, diameter greater than 6 cm, tumor crossing the midline and preoperative neurological deficit be considered as negative prognostic indicators when predicting overall survival in adult low grade glioma patients treated with radiotherapy. Level II It is recommended that smaller tumor size, extent of surgical resection and higher mini-mental status exam be considered as positive prognostic indicators when predicting overall survival and progression free survival in patients in adult low grade glioma patients treated with radiotherapy. Level III It is recommended that seizures at presentation, presence of oligodendroglial histological component and 1p19q deletion (along with additional relevant factors-see Table 1) be considered as positive prognostic indicators when predicting response to radiotherapy in adults with low grade gliomas. Level III It is recommended that increasing age, decreasing performance status, decreasing cognition, presence of astrocytic histological component (along with additional relevant factors (see Tables 1, 2) be considered as negative prognostic indicators when predicting response to radiotherapy.

Seizures in oligodendroglial tumors

Epilepsy develops in more than 70-90% of oligodendroglial tumors and represents a favorable indicator for long-term survival if present as the first clinical sign. Presence of IDH1 mutation is frequently associated with seizures in oligodendrogliomas, next to alterations of glutamate and GABA metabolism in the origin of glioma-associated epilepsy. Treatment by surgery or radiotherapy results in seizure freedom in about two-thirds of patients, and chemotherapy to a seizure reduction in about 50%. Symptomatic anticonvulsive therapy with levetiracetam and valproic acid as monotherapy are both evidence-based drugs for the partial epilepsies, and their effective use in brain tumors is supported by a large amount of additional data. Pharmacoresistance against anticonvulsants is more prevalent among oligodendrogliomas, occurring in about 40% despite polytherapy with two anticonvulsants or more. Toxic signs of anticonvulsants in brain tumors involve cognition, bone marrow and skin. Previous neurosurgery, radiation therapy or chemotherapy add to the risks of cognitive dysfunction.

Seizure reduction in a low-grade glioma: more than a beneficial side effect of temozolomide

BACKGROUND

Seizures are a common symptom in patients with low-grade glioma (LGG), negatively influencing quality of life, if uncontrolled. Besides antiepileptic drugs, antitumour treatment might contribute to a reduction in seizure frequency. The aim of this study was to determine the effect of temozolomide (TMZ) chemotherapy on seizure frequency, to identify factors associated with post-treatment seizure reduction and to analyse the prognostic value of seizure reduction for survival.

METHODS

We retrospectively reviewed adult patients with supratentorial LGG and epilepsy who received chemotherapy with TMZ as initial treatment or for progressive disease in two hospitals (VUmc Amsterdam; MCH The Hague) between 2002 and 2012.

RESULTS

We identified 104 patients with LGG with epilepsy who had received TMZ. Uncontrolled epilepsy in the 3 months preceding chemotherapy was present in 66 of 104 (63.5%) patients. A ≥ 50% reduction in seizure frequency after 6 months occurred in 29 of 66 (43.9%) patients. Focal symptoms at presentation (OR 6.55; 95% CI 1.45 to 32.77; p = 0.015) appeared to be positively associated with seizure reduction. Seizure reduction was an independent prognostic factor for progression-free survival (HR 0.32; 95% CI 0.15 to 0.66; p = 0.002) and overall survival (HR 0.33; 95% CI 0.14 to 0.79; p = 0.013), along with a histological diagnosis of oligodendroglioma (HR 0.38; 95% CI 0.17 to 0.86; p = 0.021). Objective responses on MRI were similar for patients with and without seizure reduction.

CONCLUSIONS

TMZ may contribute to an important reduction in seizure frequency in patients with LGG. Seizure reduction following TMZ treatment has prognostic significance and may serve as an important clinical outcome measure in patients with LGG.

Seizure outcome after radiotherapy and chemotherapy in low-grade glioma patients: a systematic review

There is growing evidence that antitumor treatment contributes to better seizure control in low-grade glioma patients. We performed a systematic review of the current literature on seizure outcome after radiotherapy and chemotherapy and evaluated the association between seizure outcome and radiological response. Twenty-four studies were available, of which 10 described seizure outcome after radiotherapy and 14 after chemotherapy. All studies demonstrated improvements in seizure outcome after antitumor treatment. Eight studies reporting on imaging response in relation to seizure outcome showed a seizure reduction in a substantial part of patients with stable disease on MRI. Seizure reduction may therefore be the only noticeable effect of antitumor treatment. Our findings demonstrate the clinical relevance of monitoring seizure outcome after radiotherapy and chemotherapy, as well as the potential role of seizure reduction as a complementary marker of tumor response in low-grade glioma patients.

Seizure control following radiotherapy in patients with diffuse gliomas: a retrospective study

BACKGROUND

Little information is available regarding the effect of conventional radiotherapy on glioma-related seizures.

METHODS

In this retrospective study, we analyzed the seizure response and outcome following conventional radiotherapy in a cohort of 43 patients with glioma (33 grade II, 10 grade III) and medically intractable epilepsy.

RESULTS

At 3 months after radiotherapy, seizure reduction was significant (≥ 50% reduction of frequency compared with baseline) in 31/43 patients (72%) of the whole series and in 25/33 patients (76%) with grade II gliomas, whereas at 12 months seizure reduction was significant in 26/34 (76%) and in 19/25 (76%) patients, respectively. Seizure reduction was observed more often among patients displaying an objective tumor response on MRI, but patients with no change on MRI also had a significant seizure reduction. Seizure freedom (Engel class I) was achieved at 12 months in 32% of all patients and in 38% of patients with grade II tumors. Timing of radiotherapy and duration of seizures prior to radiotherapy were significantly associated with seizure reduction.

CONCLUSIONS

This study showed that a high proportion of patients with medically intractable epilepsy from diffuse gliomas derive a significant and durable benefit from radiotherapy in terms of epilepsy control and that this positive effect is not strictly associated with tumor shrinkage as shown on MRI. Radiotherapy at tumor progression seems as effective as early radiotherapy after surgery. Prospective studies must confirm and better characterize the response to radiotherapy.

Iodine-125 brachytherapy for brain tumours--a review

Iodine-125 brachytherapy has been applied to brain tumours since 1979. Even though the physical and biological characteristics make these implants particularly attractive for minimal invasive treatment, the place for stereotactic brachytherapy is still poorly defined.An extensive review of the literature has been performed, especially concerning indications, results and complications. Iodine-125 seeds have been implanted in astrocytomas I-III, glioblastomas, metastases and several other tumour entities. Outcome data given in the literature are summarized. Complications are rare in carefully selected patients.All in all, for highly selected patients with newly diagnosed or recurrent primary or metastatic tumours, this method provides encouraging survival rates with relatively low complication rates and a good quality of life.

Brachytherapy for brain tumors

Over the past several decades neurooncologists have attempted to find an adjuvant treatment that prolongs survival for patients with malignant brain tumors. Brachytherapy, radiotherapy delivered by placing radioactive sources directly into the tumor, was initially thought to be the solution to this problem. Initial single institution studies showed very promising results; however, this technique has failed to show a significant survival advantage in two randomized studies. Despite this, brachytherapy continues to be used in a number of centers throughout the world for the treatment of various types of brain tumors including low-grade gliomas, anaplastic astrocytomas, glioblastomas, meningiomas and metastases. This article reviews brachytherapy's rationale, radiobiology, complications, indications, and results from numerous studies that have focused on its application for brain tumors with emphasis on its application for glial tumors.

The importance of postoperative CT image fusion verification of stereotactic interstitial irradiation for brain tumors

PURPOSE

The aim of our study was verification of the position of implanted catheters with (125)I seeds after the catheter implantation for the brachytherapy of brain tumors.

METHODS AND MATERIALS

The fusion of the CT image used at planning and after the implantation of the catheters enabled us to verify the position of the catheters containing the isotopes. After this, the tumor volume covered by the prescribed dose (TV(PD)) and the normal tissue volume covered by the prescribed dose (NTV(PD)) were compared between the plan and the actual result. The image fusion was performed by the BrainLab-Target 1.19 software on an Alfa 430 (Digital) workstation.

RESULTS

The position of the catheters was adjusted in 14 (20%) of the 70 image fusion cases being studied. The position of 16 of the 116 catheters (13.8%) required adjustment after the fusion of control images in the 70 cases studied. The Student t probe revealed a significant difference between the TV(PD) values of the reality and the plans (75.8% vs. 92.4%, p < 0.0001). There was a significant difference between values of the real performances and planning for NTV(PD) (86.8% vs. 76%, p = 0.001) and for the conformity index (0.37 vs. 0.54, p = 0.0001), too.

CONCLUSION

The application of the interstitial irradiation with CT control allows us to identify and correct possible inaccuracies in catheter positioning during the operation. The procedure then becomes far more accurate and reliable, and as such, the irradiation becomes more conformal than without catheter adjustment.

Neurocognitive and functional assessment of patients with brain metastases: a pilot study

The outcome of patients with brain metastases is generally poor. Survival alone is not necessarily a good measure of clinical outcome. Measures of neurocognitive function and the impact of the disease and treatments on functional status also need to be considered. Although these parameters have been measured in patients with primary brain tumors, they have not been as thoroughly evaluated in patients with brain metastases. The Mini-Mental State Examination provides limited assessment of neurocognitive domains impaired in brain tumor patients. It is less sensitive to mild impairment, does not avoid memorized learning from repeat administration, and does not have validated alternative forms necessary for non-English speaking patients. To determine the feasibility of using a more comprehensive neurocognitive test battery, motor, verbal, executive, and daily functions were assessed in 30 patients with brain metastases. The test battery included the Hopkins Verbal Learning Tests, Controlled Oral Word Association Test, Grooved Pegboard Test, Trailmaking Tests A and B, and the Barthel Index. In this study, there was complete patient compliance, with average test completion time of 23 +/- 6 minutes. Despite high functional status, most patients demonstrated impairment in memory and fine motor domains. Neurocognitive test batteries can and should be used in patients with brain metastases enrolled in clinical trials.

Radiation therapy for incompletely resected supratentorial low-grade glioma in adults

In this review on current concepts in radiation therapy in the treatment of incompletely resected supratentorial low-grade glioma, a number of important issues are discussed. They include indication for radiation therapy, timing (early vs delayed), dose response issue, impact of modern neuroimaging, 'optimal' treatment fields, impact of histology, new and promising approaches as well as quality of life in this disease are also discussed. This disease remains a focus of investigations in neuro-oncology owing to the fact that a number of questions discussed in the text are still far from being optimally addressed and answers are, therefore, lacking. New studies and more patients are needed to get more insight into this disease.

Psychosocial and neuropsychiatric aspects of patients with primary brain tumors

Primary brain tumors are increasing in incidence in the United States and are devastating to patients and families. Because brain tumors and their treatment primarily affect the brain, psychiatric and psychosocial impact is rather unique. As opposed to systemic effects of other tumors and treatment, brain tumors have a direct effect on brain functioning and therefore affect cognition, mood, and personality. In fact, patients undergo dramatic changes in mood and cognition, showing specific impairments in functioning. These impairments get translated into disabilities when a patient's daily functioning is impaired and may become a handicap when viewed in the context of quality of life (QOL). This article describes observed neuropsychiatric syndromes, including the apathy syndrome, and neurocognitive effects of brain tumors and their treatment. The neuropsychiatric and neurocognitive issues are discussed in the context of QOL and psychosocial and cognitive interventions available for this patient population.

Quality of life after radiation therapy of cerebral low-grade gliomas of the adult: results of a randomised phase III trial on dose response (EORTC trial 22844). EORTC Radiotherapy Co-operative Group

In 1985, the EORTC Radiotherapy Co-operative Group launched a randomised phase III study comparing high-dose (59.4 Gy in 6.5 weeks) versus low-dose (45 Gy in 5 weeks) radiotherapy with conventional techniques in patients diagnosed with low-grade cerebral glioma. The primary endpoint of the study was survival. No difference in survival was observed between the two treatment strategies. A quality of life (QoL) questionnaire consisting of 47 items assessing a range of physical, psychological, social, and symptom domains was included in the trial to measure the impact of treatment over time. Patients who received high-dose radiotherapy tended to report lower levels of functioning and more symptom burden following completion of radiotherapy. These group differences were statistically significant for fatigue/malaise and insomnia immediately after radiotherapy and in leisure time and emotional functioning at 7-15 months after randomisation. These findings suggest that for conventional radiotherapy for low-grade cerebral glioma, a schedule of 45 Gy in 5 weeks not only saves valuable resources, but also spares patients a prolonged treatment at no loss of clinical efficacy.

Cognitive functioning and quality of life in malignant glioma patients: a review of the literature

The state of current research in the psychosocial and neurocognitive functioning of primary brain tumor patients, particularly those with gliomas, is reviewed. Specific instruments that have been used to evaluate psychosocial and neurocognitive functioning in this population are reviewed. Suggestions are made, based on the review, of the most appropriate psychosocial and neurocognitive instruments to implement in clinical research. Finally, research pertaining to psychosocial and neurocognitive interventions is reviewed and suggestions for further research are outlined. Few studies have adequately addressed the cognitive and psychosocial functioning of brain tumor patients and have focused primarily on relatively insensitive measures of outcome, including IQ scores, performance status, and neurologic examinations. The use of well-accepted, psychometrically sound quality of life instruments and more specific tests of cognitive functioning need to be included in clinical trials since most current treatments have a limited effect on the length of survival. Thus, the main rationale for selecting a given brain tumor therapy may ultimately be related to its profile of neurotoxic side-effects and impact on quality of life.

Short-term CT and MR changes in brain tumors following 125I interstitial irradiation

PURPOSE

The study was undertaken to assess characteristic short-term CT and MR changes in brain tumors following 125I interstitial irradiation.

METHOD

Sixteen patients were included who had both CT and MR control examinations at regular intervals over a period of 18 months following treatment. Two groups were distinguished: low grade tumors (11 cases) and high grade malignancies (5 patients). 125I seeds were used as temporary implants. The cumulative dose was 50-60 Gy.

RESULTS

In some patients of both groups, a low attenuation spheric structure with a contrast-medium-enhanced ring and a diameter of 6-8 mm was observed. There was no edema around the structure, which represents a zone of tissue necrosis at the site of the temporary 125I implant. Tumors in both groups were completely destroyed, some decreased in size, and others were unchanged. Pseudotumor necrosis with accompanying edema occurred in two patients with low grade astrocytoma, the diameter of which was > 4 cm.

CONCLUSION

The behavior of cerebral tumors and their appearance on CT and MR images after interstitial irradiation seem to be variable. Decrease in tumor size may take place at different intervals after therapy. Brachytherapy of tumors with a diameter of > 4 cm may produce space-occupying radionecrosis.