Long-Term Outcomes for Pediatric Patients with Brain Arteriovenous Malformations Treated with Gamma Knife Radiosurgery, Part 2: The Incidence of Cyst Formation, Encapsulated Hematoma, and Radiation-Induced Tumor

OBJECTIVEContrary to the better described obliteration- and hemorrhage-related data after stereotactic radiosurgery (SRS) of brain arteriovenous malformations (AVMs) in pediatric patients, estimates of the rarer complications, including cyst and tumor formation, are limited in the literature. The aim of the present study was to assess the long-term outcomes and risks of SRS for AVMs in pediatric patients (age < 18 years).METHODSThe authors retrospectively analyzed the International Radiosurgery Research Foundation pediatric AVM database for the years 1987 to 2018. AVM obliteration, post-SRS hemorrhage, cyst formation, and tumor formation were assessed. Cumulative probabilities, adjusted for the competing risk of death, were calculated.RESULTSThe study cohort comprised 539 pediatric AVM patients (mean follow-up 85.8 months). AVM obliteration was observed in 64.3% of patients, with cumulative probabilities of 63.6% (95% CI 58.8%–68.0%), 77.1% (95% CI 72.1%–81.3%), and 88.1% (95% CI 82.5%–92.0%) over 5, 10, and 15 years, respectively. Post-SRS hemorrhage was observed in 8.4% of patients, with cumulative probabilities of 4.9% (95% CI 3.1%–7.2%), 9.7% (95% CI 6.4%–13.7%), and 14.5% (95% CI 9.5%–20.5%) over 5, 10, and 15 years, respectively. Cyst formation was observed in 2.1% of patients, with cumulative probabilities of 5.5% (95% CI 2.3%–10.7%) and 6.9% (95% CI 3.1%–12.9%) over 10 and 15 years, respectively. Meningiomas were observed in 2 patients (0.4%) at 10 and 12 years after SRS, with a cumulative probability of 3.1% (95% CI 0.6%–9.7%) over 15 years.CONCLUSIONSAVM obliteration can be expected after SRS in the majority of the pediatric population, with a relatively low risk of hemorrhage during the latency period. Cyst and benign tumor formation after SRS can be observed in 7% and 3% of patients over 15 years, respectively. Longitudinal surveillance for delayed neoplasia is prudent despite its low incidence.

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Gamma Knife Radiosurgery of Arteriovenous Malformations: Long-Term Outcomes and Late Effects

Progress in Neurological Surgery - Leksell Radiosurgery ◽

10.1159/000493070 ◽

2019 ◽

pp. 238-247

Author(s):

Bruce E. Pollock

Keyword(s):

Gamma Knife ◽

Late Effects ◽

Arteriovenous Malformations ◽

Gamma Knife Radiosurgery ◽

Long Term Outcomes

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A practical grading scale for predicting outcome after radiosurgery for arteriovenous malformations: analysis of 1012 treated patients

Journal of Neurosurgery ◽

10.3171/2013.5.jns1311 ◽

2013 ◽

Vol 119 (4) ◽

pp. 981-987 ◽

Cited By ~ 124

Author(s):

Robert M. Starke ◽

Chun-Po Yen ◽

Dale Ding ◽

Jason P. Sheehan

Keyword(s):

Multivariate Analysis ◽

Gamma Knife ◽

Arteriovenous Malformations ◽

Gamma Knife Radiosurgery ◽

Favorable Outcome ◽

Peripheral Dose ◽

Long Term Outcome ◽

Radiation Induced ◽

Grading Scale

Object The authors performed a study to review outcomes following Gamma Knife radiosurgery for cerebral arteriovenous malformations (AVMs) and to create a practical scale to predict long-term outcome. Methods Outcomes were reviewed in 1012 patients who were followed up for more than 2 years. Favorable outcome was defined as AVM obliteration and no posttreatment hemorrhage or permanent, symptomatic, radiation-induced complication. Preradiosurgery patient and AVM characteristics predictive of outcome in multivariate analysis were weighted according to their odds ratios to create the Virginia Radiosurgery AVM Scale. Results The mean follow-up time was 8 years (range 2–20 years). Arteriovenous malformation obliteration occurred in 69% of patients. Postradiosurgery hemorrhage occurred in 88 patients, for a yearly incidence of 1.14%. Radiation-induced changes occurred in 387 patients (38.2%), symptoms in 100 (9.9%), and permanent deficits in 21 (2.1%). Favorable outcome was achieved in 649 patients (64.1%). The Virginia Radiosurgery AVM Scale was created such that patients were assigned 1 point each for having an AVM volume of 2–4 cm3, eloquent AVM location, or a history of hemorrhage, and 2 points for having an AVM volume greater than 4 cm3. Eighty percent of patients who had a score of 0–1 points had a favorable outcome, as did 70% who had a score of 2 points and 45% who had a score of 3–4 points. The Virginia Radiosurgery AVM Scale was still predictive of outcome after controlling for predictive Gamma Knife radiosurgery treatment parameters, including peripheral dose and number of isocenters, in a multivariate analysis. The Spetzler-Martin grading scale and the Radiosurgery-Based Grading Scale predicted favorable outcome, but the Virginia Radiosurgery AVM Scale provided the best assessment. Conclusions Gamma Knife radiosurgery can be used to achieve long-term AVM obliteration and neurological preservation in a predictable fashion based on patient and AVM characteristics.

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Gamma Knife surgery for arteriovenous malformations in children

Journal of Neurosurgery Pediatrics ◽

10.3171/2010.8.peds10138 ◽

2010 ◽

Vol 6 (5) ◽

pp. 426-434 ◽

Cited By ~ 49

Author(s):

Chun Po Yen ◽

Stephen J. Monteith ◽

James H. Nguyen ◽

Jessica Rainey ◽

David J. Schlesinger ◽

...

Keyword(s):

Gamma Knife ◽

Arteriovenous Malformations ◽

Cyst Formation ◽

Gamma Knife Surgery ◽

Neurological Deficits ◽

Secondary Tumors ◽

Radiation Induced ◽

Induced Changes

Object The aim of this study was to evaluate the long-term imaging and clinical outcomes of intracranial arteriovenous malformations (AVMs) in children treated with Gamma Knife surgery (GKS). Methods Between 1989 and 2007, 200 patients with AVMs who were 18 years of age or younger were treated at the University of Virginia Health System. Excluding 14 patients who had not reached 2-year follow-up, 186 patients comprised this study. Hemorrhage was the most common presenting symptom leading to the diagnosis of AVMs (71.5%). The mean nidus volume was 3.2 cm3 at the time of GKS, and a mean prescription dose of 21.9 Gy was used. Results After initial GKS, 49.5% of patients achieved total angiographic obliteration. Forty-one patients whose AVM nidi remained patent underwent additional GKS. The obliteration rate increased to 58.6% after a second or multiple GKS. Subtotal obliteration was achieved in 9 patients (4.8%). Forty-nine patients (26.3%) still had a patent residual nidus. In 19 patients (10.2%), obliteration was confirmed on MR imaging only. Ten patients had 17 hemorrhages during the follow-up period. The hemorrhage rate was 5.4% within 2 years after GKS and 0.8% between 2 and 5 years. Six patients developed neurological deficits along with the radiation-induced changes. Two patients developed asymptomatic meningiomas 10 and 12 years after GKS. After a mean clinical follow-up of 98 months, less than 4% of patients had difficulty attending school or developing a career. Conclusions Gamma Knife surgery offers a reasonable chance of obliteration of an AVM in pediatric patients. The incidence of symptomatic radiation-induced changes is relatively low; however, long-term clinical and imaging follow-up is required to identify delayed cyst formation and secondary tumors.

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Stereotactic Radiosurgery for Pediatric Brain Arteriovenous Malformations: Long-Term Outcomes

Neurosurgery ◽

10.1093/neuros/nyz310_107 ◽

2019 ◽

Vol 66 (Supplement_1) ◽

Author(s):

Ching-Jen Chen ◽

Cheng-Chia Lee ◽

Kathryn N Kearns ◽

Dale Ding ◽

Douglas Kondziolka ◽

...

Keyword(s):

Stereotactic Radiosurgery ◽

Arteriovenous Malformations ◽

Cyst Formation ◽

Tumor Formation ◽

Cumulative Probability ◽

Long Term Outcomes ◽

Risk Of Death ◽

Brain Arteriovenous Malformations ◽

Cumulative Probabilities

Abstract INTRODUCTION Contrary to the better described obliteration and hemorrhage data after stereotactic radiosurgery (SRS) treatment of brain arteriovenous malformations (AVMs) in pediatric patients, estimates of the rarer complications including cyst and tumor formation are limited in the literature. The aim of the study was to assess the long-term outcomes and risks of SRS for AVMs in pediatric (age < 18 yr) patients. METHODS We retrospectively analyzed the International Radiosurgery Research Foundation pediatric AVM database from 1987 to 2018. AVM obliteration, post-SRS hemorrhage, cyst formation, and tumor formation were assessed. Cumulative probabilities, adjusted for competing risk of death, were calculated. RESULTS The study cohort comprised 539 pediatric AVM patients (mean follow-up: 85.8 mo). AVM obliteration was observed in 64.3% of patients, with cumulative probabilities of 63.6% (95% CI: 58.8%-68.0%), 77.1% (95% CI: 72.1%-81.3%), and 88.1% (95% CI: 82.5%-92.0%) over 5, 10, and 15 yr, respectively. Post-SRS hemorrhage was observed in 8.4% of patients, with cumulative probabilities of 4.9% (95% CI: 3.1%-7.2%), 9.7% (95% CI: 6.4%-13.7%), and 14.5% (95% CI: 9.5%-20.5%) over 5, 10, and 15 yr, respectively. Cyst formation was observed in 2.1% of patients, with cumulative probabilities of 5.5% (95% CI: 2.3%-10.7%) and 6.9% (95% CI: 3.1%-12.9%) over 10 and 15 yr, respectively. Meningioma was observed in 2 patients (0.4%) at 10 and 12 yr after SRS, with cumulative probability of 3.1% (95% CI: 0.6%-9.7%) over 15 yr. CONCLUSION AVM obliteration can be expected after SRS in the majority of the pediatric population, with a relatively low risk of hemorrhage during the latency period. Cyst and benign tumor formation after SRS can be observed in 7% and 3% of patients over 15 yr, respectively. Longitudinal surveillance for delayed neoplasia is prudent despite its low incidence.

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Stereotactic radiosurgery for cerebral arteriovenous malformations: evaluation of long-term outcomes in a multicenter cohort

Journal of Neurosurgery ◽

10.3171/2015.9.jns151311 ◽

2017 ◽

Vol 126 (1) ◽

pp. 36-44 ◽

Cited By ~ 52

Author(s):

Robert M. Starke ◽

Hideyuki Kano ◽

Dale Ding ◽

John Y. K. Lee ◽

David Mathieu ◽

...

Keyword(s):

Gamma Knife ◽

Arteriovenous Malformations ◽

Predictors Of Outcome ◽

Cerebral Arteriovenous Malformations ◽

Long Term Outcomes ◽

Radiation Induced ◽

Cerebral Avms ◽

Grading Scales

OBJECTIVE In this multicenter study, the authors reviewed the results following Gamma Knife radiosurgery (GKRS) of cerebral arteriovenous malformations (AVMs), determined predictors of outcome, and assessed predictive value of commonly used grading scales based upon this large cohort with long-term follow-up. METHODS Data from a cohort of 2236 patients undergoing GKRS for cerebral AVMs were compiled from the International Gamma Knife Research Foundation. Favorable outcome was defined as AVM obliteration and no posttreatment hemorrhage or permanent symptomatic radiation-induced complications. Patient and AVM characteristics were assessed to determine predictors of outcome, and commonly used grading scales were assessed. RESULTS The mean maximum AVM diameter was 2.3 cm, with a mean volume of 4.3 cm3. A mean margin dose of 20.5 Gy was delivered. Mean follow-up was 7 years (range 1–20 years). Overall obliteration was 64.7%. Post-GRKS hemorrhage occurred in 165 patients (annual risk 1.1%). Radiation-induced imaging changes occurred in 29.2%; 9.7% were symptomatic, and 2.7% had permanent deficits. Favorable outcome was achieved in 60.3% of patients. Patients with prior nidal embolization (OR 2.1, p < 0.001), prior AVM hemorrhage (OR 1.3, p = 0.007), eloquent location (OR 1.3, p = 0.029), higher volume (OR 1.01, p < 0.001), lower margin dose (OR 0.9, p < 0.001), and more isocenters (OR 1.1, p = 0.011) were more likely to have unfavorable outcomes in multivariate analysis. The Spetzler-Martin grade and radiosurgery-based AVM score predicted outcome, but the Virginia Radiosurgery AVM Scale provided the best assessment. CONCLUSIONS GKRS for cerebral AVMs achieves obliteration and avoids permanent complications in the majority of patients. Patient, AVM, and treatment parameters can be used to predict long-term outcomes following radiosurgery.

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