Safety Of Gamma Knife Radiosurgery Research Articles

Efficacy and Cognitive Outcomes of Gamma Knife Radiosurgery in Glioblastoma Management for Elderly Patients.

Gamma Knife Radiosurgery (GKRS), a specific type of Stereotactic Radiosurgery (SRS), has developed as a significant modality in the treatment of glioblastoma, particularly in conjunction with standard chemotherapy. The goal of this study is to evaluate the efficacy of combining GKRS with surgical resection and chemotherapy in enhancing therapeutic effects for glioblastoma patients aged 55 years and older. This prospective clinical study, conducted in accordance with the STROBE guidelines, involved 49 glioblastoma patients aged 55 years and older, treated between January 2013 and January 2023. Data were collected prospectively, and strict adherence to the STUPP protocol was maintained. Only patients who conformed to the STUPP protocol were included in the analysis. Due to concerns regarding the cognitive impairment associated with conventional radiotherapy, and at the patients' request, a radiosurgery plan was offered. Radiosurgery was administered for 4-8 weeks following surgical resection. Any patients who had not received previous radiotherapy received open surgical tumor removal, followed by GKRS along with adjuvant chemotherapy. In this prospective clinical study of 49 glioblastoma patients aged 55 years and older, the average lifespan post-histopathological diagnosis was established at 22.3 months (95% CI: 12.0-28.0 months). The median time before disease progression was 14.3 months (95% CI: 13.0-29.7 months). The median duration until the first recurrence after treatment was 15.2 months, with documented cases varying between 4 and 33 months. The Gamma Knife Radiosurgery (GKRS) treatment involved a median marginal recommended dose of 12.5 Gy, targeting an average volume of 5.7 cm3 (range: 1.6-39 cm3). Local recurrence occurred in 21 patients, while distant recurrence was identified in 8 patients. Within the cohort, 34 patients were subjected to further therapeutic approaches, including reoperation, a second GKRS session, the administration of bevacizumab and irinotecan, and PCV chemotherapy. A cognitive function assessment revealed that the patients treated with GKRS experienced significantly less cognitive decline compared to the historical controls, who were treated with conventional radiotherapy. The median MMSE scores declined by 1.9 points over 12 months, and the median MoCA scores declined by 2.9 points. This study demonstrates that Gamma Knife Radiosurgery (GKRS), when integrated with surgical resection and adjuvant chemotherapy, offers a substantial benefit for glioblastoma patients aged 55 years and older. The data reveal that GKRS not only prolongs overall survival and progression-free survival but also significantly reduces cognitive decline compared to conventional radiotherapy. These findings underscore the efficacy and safety of GKRS, advocating for its incorporation into standard treatment protocols for older glioblastoma patients. The potential of GKRS to improve patient outcomes while preserving cognitive function is compelling and warrants further research to optimize and confirm its role in glioblastoma management.

Clinical and Radiological Response Following Single-Session Gamma Knife Radiosurgery in Cavernous Sinus Hemangiomas

Abstract Purpose Cavernous sinus hemangiomas (CSH) represent 2 to 3% of lesions occupying the cavernous sinus. The optimal management strategy for CSH is not established, with microsurgical resection and radiosurgery employed alone or in combination. Therefore, we aimed to analyze the efficacy and safety of gamma knife radiosurgery (GKRS) for CSH in a cohort of primary and residual CSH. Methods A retrospective analysis of 33 patients (26 primary and 7 residual CSH) that underwent single-session GKRS between 2012 and 2021 for CSH was performed. Demographic, clinical, radiological, and follow-up data were acquired, and clinicoradiological response following GKRS was assessed. Results The mean age of the cohort was 43 ± 13.5 years (range, 10–77). There were 9 males (27.3%) and 24 females (72.7%). The median lesion volume was 6.9 cc, ranging from 1.46 to 19.06 cc. The mean dose administered to the tumor margin was 13.50 ± 1.5 Gy (range, 12 to 15 Gy). The median duration of clinical follow-up was 41 months, over which period the mean reduction in tumor volume was 87.6%. Complete response, defined as absence of tumor on follow-up imaging, occurred in 23 patients (69.7%). Twenty-three patients (69.7%) showed clinical improvement following GKRS. There were no radiation-induced complications. Conclusion CSH have a distinct radiological appearance and a predictable response to radiosurgery. When used primarily in radiologically diagnosed CSH and as adjunctive therapy supplementing a subtotal excision, GKRS produces a high rate of volume reduction with the improvement of neurological function and minimal cranial nerve morbidity. Therefore, GKRS presents a viable alternative to surgery without the morbidity associated with surgical resection.

Gamma knife radiosurgery in patients with Cushing's Disease: Is it a curative option?

BackgroundThe first line of treatment of Cushing’s disease (CD) is surgery. However, surgical resection is not amenable in all cases and the role of radiosurgical management of residual tumors or upfront treatment has been reported. Our study highlights the effectiveness and safety of Gamma Knife Radiosurgery for the treatment of Cushing’s disease.MethodsThis was an ambidirectional descriptive cohort study on 16 consecutive patients with a confirmed Cushing’s disease that underwent Gamma Knife Radiosurgery (GKR) before July 2014 and assessed for outcome during the study period between January 2014 and June 2016 (30 Months). We included patients with a minimum of two years follow up. The main outcomes were biochemical remission and tumor volume control. Secondary outcomes were visual field changes and morbidity.ResultsSixteen cases with CD were included into the study. The Mean age ± SD was 34.81 ± 10.10 years. The male to female sex ratio was 1:3.Six cases (37.5%) were de novo. Normalization of hypersecretion at 2 years was achieved in 13 cases (81.3%).The median hormone normalization time was 23 months. Tumor volume control was achieved in all the cases, whereas tumor shrinkage was achieved in (10 cases) 62.5%. The median shrinkage time was 13 months. Of the 12 eyes with pre-Gamma Knife visual affection, 8 (75%) normalized, 4 (25%) improved, and none deteriorated. No patient developed new hypopituitarism after GK radiosurgery. One case developed diplopia at 24 months follow up from abducens palsy. No mortality occurred in our series.ConclusionGamma Knife Stereotactic Radiosurgery is an effective and safe treatment option for Cushing’s disease. It can be used as a complementary therapeutic procedure to classic surgery or as a first line treatment in selected number of patients.

Long-term safety of gamma knife radiosurgery (SRS) for acromegaly

PurposeAcromegaly has high morbidity and mortality when growth hormone secretion remains uncontrolled. Stereotactic radiosurgery (SRS) may be used when pituitary surgery is not suitable or unsuccessful, but there are few very long-term safety data available, especially for significant adverse events such as stroke.Methods118 patients with acromegaly were treated with SRS between 1985 and 2015, at the National Centre for Stereotactic Radiosurgery, Sheffield, UK. Data were gathered from case notes, hospital databases, and patient questionnaires. Stroke incidence in comparison to the normal population was quantified using the standardised incidence ratio (SIR), and visual complications assessed.Results88% (104/118) had complete morbidity follow up data for analysis. The mean follow-up was 134 months, and median SRS dose was 30 Gy. 81% of tumours had cavernous sinus invasion. There was no excess stroke rate relative to that seen in two age- and sex-matched large population studies (SIR = 1.36, 95% CI 0.27–3.96; SIR = 0.52, 95% CI 0.06–1.89). In 68/104 patients who had MRI-guided SRS with no further radiation treatment (SRS or fractionated radiotherapy) there was no loss of visual acuity and 3% developed ophthalmoplegia. There was a positive correlation between > 1 radiation treatment and both ophthalmoplegia and worsening visual acuity.ConclusionStroke rate is not increased by SRS for acromegaly. Accurate MRI-based treatment planning and single SRS treatment allow the lowest complication rates. More than one radiation treatment (SRS or fractionated radiotherapy) was associated with increased visual complications.

Gamma Knife radiosurgery for the treatment of central neurocytoma: a single-institution experience of 25 patients.

Central neurocytomas (CNs) are extremely rare tumors that account for 0.1-0.5% of all intracranial neoplasms. Recently, Gamma Knife radiosurgery (GKRS) has become a treatment option in patients with CN. We aimed to evaluate the efficacy and safety of GKRS in 25 CN patients and review the results along with relevant literature. GKRS patient database was searched, and 25 patients who underwent GKRS for CN between 2009 and 2018, were evaluated retrospectively. The study cohort included 15 female and ten male patients with a median age of 32 years (range, 5-60). The most common presenting symptom was headache (88%). The neurological examination was unremarkable in all patients, except for one patient with decreased vision. Twenty patients (80%) had a history of surgical resection. Most of the tumors (92%) were located in the ventricles, and the median tumor volume was 4.8 cm3 (range, 0.8-28.1). The median marginal dose was 14 Gy (range, 12-15) to a median isodose of 50% (range, 40-50). Following a median follow-up of 80 months (range, 36-138), local tumor control was achieved in 100% of patients. Distant recurrence was observed in one patient (4%). No adverse radiation effect was observed. Regarding non-specific post-GKRS symptoms, one patient experienced a prolonged headache, and one epileptic patient experienced a brief partial seizure. In our patient cohort, GKRS yielded favorable local tumor control (100%) during a median follow-up of 6.6 years. Our series demonstrates that GKRS is an effective and safe treatment option for patients with primary or residual CNs.

Gamma knife radiosurgery in patients with Nelson's syndrome.

Nelson's syndrome (NS) is a long-term complication of bilateral adrenalectomy in patients with Cushing's disease. The best therapeutic strategy in NS has not been well defined. Gamma knife radiosurgery (GKRS) is very effective to stop the growth of the pituitary adenoma, which is the main goal of the treatment of patients with NS. We report the largest series of patients with NS treated by GKRS at a single center. The study was an observational, retrospective analysis of 28 consecutive patients with NS treated by GKRS in our department between 1995 and 2019. All patients had a growing ACTH-secreting pituitary adenoma. The main outcome of the study was to assess by the Kaplan-Meier method the risk of tumor progression after GKRS. The median follow-up after GKRS treatment was 98months (IQR 61-155months, range 7-250months). Two patients (7.1%) had a recurrence of disease during follow-up. The 10-year progression-free survival was 91.7% (95% CI 80.5-100%). No patient had deterioration of visual function or oculomotor function after GKRS. New onset of hypogonadism and hypothyroidism occurred in 18.8% and 14.3% of the patients at risk. Our study confirms that GKRS may stop the tumor growth in the majority of patients with NS, even though very aggressive adenomas may ultimately escape this treatment. Safety of GKRS was good in our experience, but due attention must be paid to planning the distribution of radiation to critical structures, especially in patients previously treated by radiation.

Acute Management of Gamma Knife Radiosurgery for Asymptomatic Obstructive Hydrocephalus Associated with Posterior Fossa Metastases

We retrospectively assessed the effectiveness and safety of Gamma Knife radiosurgery (GKRS) for asymptomatic obstructive hydrocephalus associated with posterior fossa metastases, which was known empirically but not well discussed. We reviewed the medical records of 27 patients who underwent GKRS for asymptomatic obstructive hydrocephalus related to posterior fossa metastases. Cumulative control rates of hydrocephalus were 11.1%, 51.9%, 70.4%, and 74.6% at 1, 2, 3, and 6 months after GKRS. Primary gastrointestinal tract cancer (P= 0.001) was significantly correlated with unfavorable management. Evans ratio at GKRS (median 0.31) improved significantly compared with that at 1-3 months after GKRS (median 0.26) (P < 0.0001) and maintained at 6 to 12 months. Cumulative local tumor control rates were 91.7%, 70.8%, and 64.4% at 3, 6, and 12 months after GKRS. Primary gastrointestinal tract cancer (P= 0.018) and no conventional systemic agents (P= 0.027) were significantly correlated with unfavorable control. Cumulative incidence rates of adverse radiation effects were 0.0%, 16.7%, and 24.2% at 6, 9, and 12 months after GKRS. Primary gastrointestinal tract cancer (P < 0.0001) and single and 2- or 3-fraction GKRS (P < 0.0001) were significantly correlated with unfavorable outcomes. All but 1 patient avoided surgical procedure for hydrocephalus after GKRS. The present findings suggest that GKRS is an effective and safe treatment for asymptomatic obstructive hydrocephalus caused by posterior fossa metastases, and all but 1 could avoid invasive surgical procedures for hydrocephalus. Posterior fossa metastases from gastrointestinal tract cancer resulted in unsatisfactory outcomes for control of hydrocephalus, tumor progression, and adverse radiation effects.

GAMMA KNIFE RADIOSURGERY ROLE IN THE MANAGEMENT OF BRAIN STEM CAVERNOUS ANGIOMAS

Background: Cavernous angioma or cavernoma is a benign vascular malformation, which can be found at any region within the brain. Brain stem cavernous angioma is rare. Although the optimal management of intracranial cavernous angiomas is open resection, Gamma Knife radiosurgery (GKR) has played an important role in treating these deeply seated and high surgical risk malformations throughout the past 20 years. Aim of the study: Our study aimed to evaluate the efficacy, and safety of Gamma Knife radiosurgery in the management of brainstem cavernous angiomas.Patients and Methods: Our retrospective study was conducted on 22 patients with brainstem cavernous hemangioma who underwent gamma knife at the Gamma Knife center (GKC), Nasser Institute Hospitals, Cairo in collaboration with department of neurosurgery, Ain Shams University. Follow up period 24-132 months, mean follow up period 51 months.Results: In the present series we have satisfactory results as regards reducing rebleeding rate, we have post radiosurgeryrebleeding rate of 2.8%. It represents the sum of the bleeding rate for all patients in the study including those who have rebleeding rate 30% preradiosurgical. As regards control of improvement of presenting manifestations, we have also excellent results in the present series (75%) of patients showed improvement of the symptoms, (25%) remained stable clinically. Reduction of cavernoma size after treatment was observed also in our series for 77.3% of the lesions. There was no permanent morbidity post gamma knife, only 3 transient morbidities were happened due to edema and bleeding.Conclusion: As the development of stereotaxic radiosurgery and more experience accumulated, GKR has become an effective and safe alternative method for brainstem cavernous angiomas treatment.

Salvage gamma knife radiosurgery for active brain metastases from small-cell lung cancer after whole-brain radiation therapy: a retrospective multi-institutional study (JLGK1701).

To evaluate the efficacy of gamma knife radiosurgery (GKS) for brain metastases (BMs) from small-cell lung cancer after whole-brain radiotherapy (WBRT). We retrospectively analyzed the usefulness and safety of GKS in 163 patients from 15 institutions with 1-10 active BMs after WBRT. The usefulness and safety of GKS were evaluated using statistical methods. The median age was 66years, and 79.1% of patients were men. The median number and largest diameter of BM were 2.0 and 1.4cm, respectively. WBRT was administered prophylactically in 46.6% of patients. The median overall survival (OS) was 9.3months, and the neurologic mortality was 20.0%. Crude incidences of local control failure and new lesion appearance were 36.6% and 64.9%, respectively. A BM diameter ≥ 1.0cm was a significant risk factor for local progression (hazard ratio [HR] 2.556, P = 0.039) and neurologic death (HR 4.940, P = 0.031). Leukoencephalopathy at the final follow-up was more prevalent in the therapeutic WBRT group than in the prophylactic group (P = 0.019). The symptom improvement rate was 61.3%, and neurological function was preserved for a median of 7.6months. Therapeutic WBRT was not a significant risk factor for OS, neurological death, local control, or functional deterioration (P = 0.273, 0.490, 0.779, and 0.560, respectively). Symptomatic radiation-related adverse effects occurred in 7.4% of patients. GKS can safely preserve neurological function and prevent neurologic death in patients with 1-10 small, active BMs after prophylactic and therapeutic WBRT.

P.013 Symptom stability in de novo and rollover patients with bipolar I disorder receiving aripiprazole once-monthly in a 52-week, open-label study

To evaluate the efficacy and safety of Gamma Knife Radiosurgery (GKRS) in the treatment of single and multiple brain metastases.From October 2012 to June 2014 106 patients were treated with Radiosurgery (RS) for brain metastases at University of Florence. 77 out of 106 patients had a radiological follow up and their data were analyzed. The target was defined as the enhancing lesion. The prescription dose was defined depending on tumor volume and tumor location. Each patient performed an MRI one month after GKRS for the first three months and every 3 months thereafter. Overall survival was calculated from the day of RS until death. Local recurrence (LR) was defined as radiologic growth of the irradiated lesion, while distant brain recurrence (DBR) was the evidence of brain lesion outside the previous irradiated field. Both the LR and DBR were calculated from the RS till the day of radiological evidence of relapse. The correlations within patient and disease characteristics and the outcomes of survival and disease control were analyzed.Mean follow up was 7.2 ± 4.8 months (range: 2.4–22.8 months). At the time of analysis 21 patients (27.3%) were dead. The overall survival (OS) at 1 year was 74%. On univariate Cox Regression analysis female gender (p = 0.043, HR: 0.391, 95% CI: 0.157–0.972) and age >65 years (p = 0.003 HR: 4.623, 95% CI: 1.687–12.663) were predictive for survival. On multivariate analysis, age older than 65 years (p = 0.005HR: 4.254, 95% CI: 1.544–11.721) was confirmed as associated with worsened overall survival. 19 patients (24.7%) had recurrence in the radiosurgery field. The median time to local failure was 4.8 ± 2.0 months (range: 1.8–9.4 months) from GKRS. On Cox Regression univariate analysis, the only factor associated with higher risk of local failure was a number of treated lesions more than 4 (p = 0.015, HR: 3.813, 95% CI: 1.298–11.202), no significant parameters were found at the multivariate analysis. The median time to develop distant brain failure was 6 ± 4.32 months (range: 1.08–21.6 months). Median distant brain control was 74% at 1 year. None of the factors analyzed was statistically significant for the distant brain relapse. The radiosurgery treatment was well tolerated. One patient treated for seven metastases developed seizures 8 h after GKRS, he was treated with steroids and anticonvulsants. One patient had radiologic evidence of radionecrosis without any neurological symptoms.In well-performing patients with stable systemic disease radiosurgery can be performed as an exclusive treatment for brain metastases. Younger patients could have a greater benefit from the RS, on the other hand our finding confirm no correlation between the survival outcome and the number of lesions treated.

Gamma Knife radiosurgery for cerebral cavernous malformation

This is a retrospective study examining the efficacy and safety of Gamma Knife radiosurgery (GKS) in treating patients with cerebral cavernous malformations (CCMs). Between 1993 and 2018, 261 patients with 331 symptomatic CCMs were treated by GKS. The median age was 39.9 years and females were predominant (54%). The median volume of CCMs was 3.1 mL. The median margin dose was 11.9 Gy treat to a median isodose level of 59%. Median clinical and imaging follow-up times were 69 and 61 months, respectively. After the initial hemorrhage that led to CCM diagnosis, 136 hemorrhages occurred in the period prior to GKS (annual incidence = 23.6%). After GKS, 15 symptomatic hemorrhages occurred within the first 2 years of follow-up (annual incidence = 3.22%), and 37 symptomatic hemorrhages occurred after the first 2 years of follow-up (annual incidence = 3.16%). Symptomatic radiation-induced complication was encountered in 8 patients (3.1%). Mortality related to GKS occurred in 1 patient (0.4%). In conclusion, GKS decreased the risk of hemorrhage in CCM patients presenting with symptomatic hemorrhage. GKS is a viable alternative treatment option for patients with surgically-inaccessible CCMs or significant medical comorbidities.

OS8.3 Gamma knife radiosurgery for large meningiomas: 10 years of experience

Abstract BACKGROUND The use of gamma knife radiosurgery for the treatment of intracranial meningiomas has been established as an effective and safe treatment modality. Larger meningiomas are typically managed by surgery followed by radiosurgery. For situations where patients are not amenable to surgery fractionated stereotactic radiotherapy is the traditionally suggested treatment. Treatment of large meningiomas (usually defined as &gt;10 cc) by stereotactic radiosurgery has been investigated in some recent reports, either by single-session, volume-staged or hypofractionation technique. However, there are no long-term results. The purpose of this study is to assess the long-term efficacy and safety of gamma knife radiosurgery for large (15 cc or more) intracranial meningiomas. MATERIAL AND METHODS In this study we included 80 patients with large meningiomas (³ 15 cc) who were followed up for more than 5 years. Non-benign meningiomas were excluded. Also, meningiomatosis and NF2 patients were not included. There were 18 males (22.5%) and 62 females (77.5%). The mean age was 46 years (20–83 years). Twenty-six patients (32.5%) had previous surgery. Tumor were supratentorial in 14 (17.5%) patients and skull base in 66 (82.5%) patients. The mean tumor volume was 22.3 cc (15–57.3 cc). The mean prescription dose was 11 Gy (9–12 Gy). RESULTS The mean follow up period was 8.4 years (5–17 years). The tumor shrank in 43 patients (54%), was stable in 30 patients (37%) and progressed in 7 patients (8%). The tumor control rate was 91%. Adverse radiation effects were observed in 11 patients (14%) but only 5 (6.5%) were symptomatic. These were temporary in all cases. CONCLUSION Gamma knife radiosurgery provides an effective and safe treatment option for large meningiomas. Low margin dose appears to be sufficient for tumor control. Surgery remains the first option in these cases.

Efficacy and Safety of Gamma Knife Radiosurgery for Meningiomas in Patients with Neurofibromatosis Type 2: A Long-Term Follow-Up Single-Center Study

To explore the efficacy and safety of Gamma Knife radiosurgery (GKRS) for meningiomas in patients with neurofibromatosis type 2 (NF2). A series of 35 consecutive patients with 99 meningiomas in our department were retrospectively included from January 2000 to December 2015. Clinical records, magnetic resonance images, and follow-up data were reviewed. A total of 35 patients (25 women and 10 men) with 99 NF2-associated meningiomas were identified. All patients initially received GKRS. The patients' median age at the time of GKRS was 40 years (range, 16-61 years). The median prescription dose at the tumor margin was 13 Gy (range, 12-15 Gy). The median follow-up time was 96 months (range, 25-224 months). Twenty-nine patients received GKRS only once, and 6 patients received it multiple times. Six patients (17.1%) had radiation-related complications 7.5 ± 2.4 months after GKRS. Local control rates at 1, 3, and 5 years were 100%, 97.1%, and 90.6%, respectively. Distant control rates at 1, 3, and 5 years were 88.5%, 55.9%, and 45.5%, respectively. Five patients died of concomitant neurologic symptoms. No malignant transformation was observed during the follow-up periods in all 35 patients. GKRS represents an effective and safe management strategy with minimal invasion for patients with NF2-associated meningiomas. Our data showed a high local control rate of NF2-associated meningiomas by GKRS; however, the distant control rate is low, especially in young patients. For these patients, retreatment with GKRS may still be the advisable method.

The efficacy of gamma knife radiosurgery in patients with trigeminal neuralgia: The initial experience of the Bezmialem Vakif University.

Gamma knife stereotactic radiosurgery is, compared with surgical treatment, a less invasive treatment option for patients with trigeminal neuralgia (TN). In this report, we analyzed the effect and safety of gamma knife radiosurgery performed in patients with TN. We retrospectively reviewed patients who underwent gamma knife radiosurgery for TN between June 2014 and January 2017. All patients were treated with Leksell Gamma Knife Model C (Elekta, Stockholm, Sweden) with a prescription dose of 40 Gy with a 50% isodose line. The follow-up of the patients was performed 1 week after the procedure and after every 3 months. The pain score of the patients was recorded using the visual analog scale (VAS). Complications were also reviewed. Statistical analysis was performed using the Statistical Package for the Social Sciences software for Windows, version 23.0. Twenty-four patients (10 males, 14 females) were included in the study. The median age of the patients was 62.5 years (range, 34-91 years). The pre-gamma knife median VAS was 10 (range, 5-10), and the median VAS was 1 (range, 0-10) during the last follow-up. The pain decreased in 16 (76%) patients. Two patients (9%) had treatment-related complications. One patient developed hypoesthesia along the dermatome of the maxillary branch of the fifth cranial nerve and another patient developed facial paresis, which recovered after the usage of steroids for 3 months. Gamma knife radiosurgery is an effective and safe treatment for patients with TN with an acceptable pain control rate.

Long-term safety of gamma knife radiosurgery (STRS) for acromegaly

Purpose Acromegaly has high morbidity and mortality when growth hormone secretion remains uncontrolled. Stereotactic radiosurgery (SRS) may be used when pituitary surgery is not suitable or unsuccessful, but there are few very long-term safety data available, especially for significant adverse events such as stroke. Methods 118 patients with acromegaly were treated with SRS between 1985 and 2015, at the National Centre for Stereotactic Radiosurgery, Sheffield, UK. Data were gathered from case notes, hospital databases, and patient questionnaires. Stroke incidence in comparison to the normal population was quantified using the standardised incidence ratio (SIR), and visual complications assessed. Results 88% (104/118) had complete morbidity follow up data for analysis. The mean follow-up was 134 months, and median SRS dose was 30 Gy. 81% of tumours had cavernous sinus invasion. There was no excess stroke rate relative to that seen in two age- and sex-matched large population studies (SIR = 1.36, 95% CI 0.27–3.96; SIR = 0.52, 95% CI 0.06–1.89). In 68/104 patients who had MRI-guided SRS with no further radiation treatment (SRS or fractionated radiotherapy) there was no loss of visual acuity and 3% developed ophthalmoplegia. There was a positive correlation between > 1 radiation treatment and both ophthalmoplegia and worsening visual acuity. Conclusion Stroke rate is not increased by SRS for acromegaly. Accurate MRI-based treatment planning and single SRS treatment allow the lowest complication rates. More than one radiation treatment (SRS or fractionated radiotherapy) was associated with increased visual complications.

Treating intracranial dural arteriovenous fistulas with gamma knife radiosurgery: A single-center experience.

Objective:We evaluated the effectiveness and safety of gamma knife radiosurgery (GKRS) for the treatment of intracranial dural arteriovenous fistulas (dural AVFs) over the past 10 years.Materials and Methods:The records of 21 patients diagnosed with dural AVFs between 2004 and 2014 and treated with GKRS were reviewed retrospectively. Complete obliteration (CO) was defined as total symptom relief plus confirmation through magnetic resonance imaging or conventional angiography.Results:The median follow-up was 70.5 months (range 3–136 months). Five patients underwent embolization (2 after GKRS). One patient underwent GKRS twice. The CO rate was 47%, and partial to CO rate was 88%. The complete symptom resolution rate was 77%, and all patients achieved partial to complete symptom resolution. The CO rates for Borden Type I and Type II/III dural AVFs were 66.7% and 25% (P = 0.153), respectively, and complete symptom-free rates were 76.9% and 75.0% (P = 1.000%), respectively. The median duration between initial GKRS and complete symptom resolution was 14.3 months. The median treatment to image-free durations for Borden Type I and Type II/III dural AVFs were 25.9 and 60.4 months (P = 0.028), respectively, and treatment to symptom-free durations were 10.6 and 36.7 months (P = 0.103), respectively. One patient had a recurrent hemorrhage. Two patients experienced brain edema after stereotactic radiosurgery and one patient experienced cystic formation after GKRS. The morbidity rate was 19% (four patients) and there was no mortality.Conclusion:Treatment with GKRS for dural AVFs offers a favorable rate of obliteration. Patients with dural AVFs that are refractory or not amenable to endovascular or surgical therapy may be safely and effectively treated using GKRS.

Gamma knife radiosurgery for brainstem cavernous malformations

ObjectiveThe goal of this retrospective study was to evaluate the efficacy and safety of gamma knife radiosurgery (GKS) for the treatment of brainstem cavernous malformations (CMs). MethodsBetween January of 2009 and December of 2014, 43 patients (20 males and 23 females) with brainstem CMs were treated at the West China Hospital, Sichuan University, Gamma Knife Center. The mean age of these patients was 41.7 years. All of the patients experienced 1 or more episodes of symptomatic bleeding (range 1–4) before undergoing GKS. The mean volume of the malformations at the time of GKS was 442.1mm3, and the mean prescribed marginal radiation dose was 11.9Gy. The mean follow-up period after radiosurgery was 36 months (range 12–120 months). ResultsBefore GKS, 50 hemorrhages (1.2 per patient) were observed (25.0% annual hemorrhage rate). Three hemorrhages following GKS were observed within the first 2 years (3.92% annual hemorrhage rate), and 1 hemorrhage was observed in the period after the first 2 years (1.85% annual hemorrhage rate). In this study of 43 patients, new neurological deficits developed in only 1 patient (2.32%; permanent paresthesia on the left side of the face and the right lower limb of the patient). There were no deaths in this study. ConclusionGKS is a favorable alternative treatment for brainstem CMs. Using a low marginal dose treatment might reduce the rate of hemorrhage and radiation-induced complications.

P19.03 Randomized double arm phase III study to evaluate feasibility and safety of Gamma Knife radiosurgery versus Linac Based (Edge) radiosurgery in brain metastatic patients

P19.03 Randomized double arm phase III study to evaluate feasibility and safety of Gamma Knife radiosurgery versus Linac Based (Edge) radiosurgery in brain metastatic patients

Gamma Knife Radiosurgery in the management of single and multiple brain metastases

ObjectivesTo evaluate the efficacy and safety of Gamma Knife Radiosurgery (GKRS) in the treatment of single and multiple brain metastases. Patients and methodsFrom October 2012 to June 2014 106 patients were treated with Radiosurgery (RS) for brain metastases at University of Florence. 77 out of 106 patients had a radiological follow up and their data were analyzed. The target was defined as the enhancing lesion. The prescription dose was defined depending on tumor volume and tumor location. Each patient performed an MRI one month after GKRS for the first three months and every 3 months thereafter. Overall survival was calculated from the day of RS until death. Local recurrence (LR) was defined as radiologic growth of the irradiated lesion, while distant brain recurrence (DBR) was the evidence of brain lesion outside the previous irradiated field. Both the LR and DBR were calculated from the RS till the day of radiological evidence of relapse. The correlations within patient and disease characteristics and the outcomes of survival and disease control were analyzed. ResultsMean follow up was 7.2±4.8 months (range: 2.4–22.8 months). At the time of analysis 21 patients (27.3%) were dead. The overall survival (OS) at 1 year was 74%. On univariate Cox Regression analysis female gender (p=0.043, HR: 0.391, 95% CI: 0.157–0.972) and age >65 years (p=0.003 HR: 4.623, 95% CI: 1.687–12.663) were predictive for survival. On multivariate analysis, age older than 65 years (p=0.005HR: 4.254, 95% CI: 1.544–11.721) was confirmed as associated with worsened overall survival. 19 patients (24.7%) had recurrence in the radiosurgery field. The median time to local failure was 4.8±2.0 months (range: 1.8–9.4 months) from GKRS. On Cox Regression univariate analysis, the only factor associated with higher risk of local failure was a number of treated lesions more than 4 (p=0.015, HR: 3.813, 95% CI: 1.298–11.202), no significant parameters were found at the multivariate analysis. The median time to develop distant brain failure was 6±4.32 months (range: 1.08–21.6 months). Median distant brain control was 74% at 1 year. None of the factors analyzed was statistically significant for the distant brain relapse. The radiosurgery treatment was well tolerated. One patient treated for seven metastases developed seizures 8h after GKRS, he was treated with steroids and anticonvulsants. One patient had radiologic evidence of radionecrosis without any neurological symptoms. ConclusionsIn well-performing patients with stable systemic disease radiosurgery can be performed as an exclusive treatment for brain metastases. Younger patients could have a greater benefit from the RS, on the other hand our finding confirm no correlation between the survival outcome and the number of lesions treated.

Radiosurgical considerations for cavernous sinus hemangioma: long-term clinical outcomes.

Cavernous hemangiomas are rare vascular tumors in the cavernous sinus. Cranial neuropathies induced by cavernous sinus hemangiomas (CSH) necessitate tumor reduction, but surgery is extremely difficult due to the abundant vascularization of the lesion. We studied the effectiveness and safety of Gamma Knife radiosurgery (GKRS) for CSH. We performed a retrospective analysis of 25 patients with CSH who were treated by GKRS between March 1992 and December 2014. Age, sex, target volume, and irradiation dose were analyzed as prognostic factors for CSH treated by GKRS. Eleven (84.6%) patients had tumor shrinkage within 12months after GKRS. Two patients experienced tumor progression, but tumor size decreased over 2years after GKRS. No patients had permanent complications, and all patients experienced symptomatic improvement. There were no significant factors that predicted the prognosis of CSH. The optimal treatment for CSH has been unclear; however, in this study, GKRS was an effective and safe treatment for CSH. Thus, GKRS may be a primary treatment for CSHs in high-risk surgery patients.