Gamma Knife radiosurgery for cavernous malformation


Gamma Knife radiosurgery for cavernous malformation

Stereotactic radiosurgery (SRS) is a therapeutic option for repeatedly hemorrhagic cavernous malformations (CMs) located in areas deemed to be high risk for resection. During the latency period of 2 or more years after SRS, recurrent hemorrhage remains a persistent risk until the obliterative process has finished. The pathological response to SRS has been studied in relatively few patients.


Gamma Knife radiosurgery (GKRS) has been used to treat cavernous malformations (CMs) located in basal ganglia and thalamus. However, previous reports are limited by small patient population.

Hu et al. retrospectively reviewed the clinical and radiological data of 53 patients with CMs of basal ganglia and thalamus who underwent GKRS at West China Medical Center between May 2009 and July 2018. All patients suffered at least once bleeding before GKRS. The mean volume of these lesions was 1.77 cm3, and the mean marginal dose was 13.2 Gy. After treatment, patients were followed to determine the change in symptom and hemorrhage event.

The mean follow-up period was 52.1 months (6.2-104.3 months). The calculated annual hemorrhage rate (AHR) was 48.5% prior to GKRS and 3.0% after treatment (p < 0.001). The Kaplan-Meier analysis revealed that 2-, 3-, and 5-year hemorrhage-free survival were 88, 80.9, and 80.9%, respectively. Preexisting symptoms were resolved in 11 patients, improved in 14, and stable in 5. Only 2 patients (3.8%) developed new neurological deficit.

This study suggests that AHR after GKRS was comparable to the recorded AHR of natural history (3.1-4.1%) in previous studies. GKRS is a safe and effective treatment modality for CMs of basal ganglia and thalamus. Considering the relative insufficient understanding of natural history of CMs, future study warrants longer follow-up 1)

Wen et al., from the West China Hospital performed a meta-analysis is to evaluate the clinical efficacy of gamma knife radiosurgery for treating cavernous malformation.

PUBMEDOVID EMBASE, and OVID MEDLINE electronic databases are searched. The primary outcome is hemorrhage rate and this meta-analysis is performed with REVMAN 5.3.

9 studies are included in this meta-analysis. The overall RR of hemorrhage rate of pre-GKRS and post-GKRS is 6.08(95% CI: 5.04-7.35). The overall RR is 3.03(95% CI: 2.65-4.11) between the hemorrhage rate of pre-GKRS and the first 2 years of post-radiosurgery, and the overall RR is 12.13 (95% CI: 1.73-85.07) comparing pre-GKRS with 2 years after GKRS. There is no significant difference of the hemorrhage rate between the first 2 years of post-radiosurgery and 2 years after GKRS (RR =2.81, 95% CI: 0.20-13.42). The neurological deficiency is the commonest radiosurgery related complications.

Patients with cerebral CMs, especially who were deep seated and surgically inaccessible, seems to benefit from GKRS due to a reduction of annual hemorrhage rate in the first 2 years, and after that time, despite of a number of cases that suffer from negative side effects of radiation 2).

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 3).


Shin et al. aimed to gain insight into the effect of SRS on CM and to propose possible mechanisms leading to recurrent hemorrhages following SRS.

During a 13-year interval between 2001 and 2013, bleeding recurred in 9 patients with CMs that had been treated using Gamma Knife surgery at the authors’ institution. Microsurgical removal was subsequently performed in 5 of these patients, who had recurrent hemorrhages between 4 months and 7 years after SRS. Specimens from 4 patients were available for analysis and used for this report.

Histopathological analysis demonstrated that vascular sclerosis develops as early as 4 months after SRS. In the samples from 2 to 7 years after SRS, sclerotic vessels were prominent, but there were also vessels with incomplete sclerosis as well as some foci of neovascularization.

Recurrent bleeding after SRS for CM could be related to incomplete sclerosis of the vessels, but neovascularization may also play a role 4).


From 1994 to 2001, 92 patients with 114 CMs were treated by GKS and then followed up for 2-8 years (mean 4.1+/-1.9). We analyzed the MRI features of CMs bleeding, efficacy of GKS, and the complications of treatment. Six pathological specimens after radiosurgery (1 from our group, 5 from other centers) were also assayed.

Among 43 patients who were treated by GKS to control their epilepsy, epileptic paroxysm was alleviated in 36 patients (83.7%), including 12 (27.9%) seizure-free. Rebleeding was confirmed in 9 patients (9.8%) by neuroimage, one of whom died. Transient symptomatic radiation edema occurred in 7 cases (7.6%) within 6-12 months after radiosurgery, and one patient underwent open surgery for cerebral decompression. The main pathological changes of cavernoma were coagulation necrosis and the vessels obliterated gradually after radiosurgery.

It is feasible to treat small and surgically high risk CMs by radiosurgery. The treatment has to be prudent in an acute bleeding and symptomatic progression. Optimal treatment timing and dose planning are prerequisites to reduce radiation-related complications. GKS is safe and effective to control the epilepsy caused by CMs, and also to bring down the rebleeding rate after a latency interval of several years 5).

Gamma knife radiosurgery for brainstem cavernous malformation.


1)

Hu YJ, Zhang LF, Ding C, Tian Y, Chen J. Gamma Knife Radiosurgery for Cavernous Malformations of Basal Ganglia and Thalamus: A Retrospective Study of 53 Patients. Stereotact Funct Neurosurg. 2021 Jun 9:1-8. doi: 10.1159/000510108. Epub ahead of print. PMID: 34107485.
2)

Wen R, Shi Y, Gao Y, Xu Y, Xiong B, Li D, Gong F, Wang W. The efficacy of gamma knife radiosurgery for cavernous malformation: a meta-analysis and review. World Neurosurg. 2018 Dec 21. pii: S1878-8750(18)32869-9. doi: 10.1016/j.wneu.2018.12.046. [Epub ahead of print] Review. PubMed PMID: 30583131.
3)

Lee CC, Wang WH, Yang HC, Lin CJ, Wu HM, Lin YY, Hu YS, Chen CJ, Chen YW, Chou CC, Liu YT, Chung WY, Shiau CY, Guo WY, Hung-Chi Pan D, Hsu SPC. Gamma Knife radiosurgery for cerebral cavernous malformation. Sci Rep. 2019 Dec 24;9(1):19743. doi: 10.1038/s41598-019-56119-1. PMID: 31874979; PMCID: PMC6930272.
4)

Shin SS, Murdoch G, Hamilton RL, Faraji AH, Kano H, Zwagerman NT, Gardner PA, Lunsford LD, Friedlander RM. Pathological response of cavernous malformations following radiosurgery. J Neurosurg. 2015 Oct;123(4):938-44. doi: 10.3171/2014.10.JNS14499. Epub 2015 Jun 19. PubMed PMID: 26090838.
5)

Liu AL, Wang CC, Dai K. [Gamma knife radiosurgery for cavernous malformations]. Zhongguo Yi Xue Ke Xue Yuan Xue Bao. 2005 Feb;27(1):18-21. Chinese. PMID: 15782486.

Cavernous sinus hemangioma Gamma Knife surgery

Cavernous sinus hemangioma Gamma Knife surgery

A study aimed to evaluate the efficacy of Gamma Knife surgery (GKS) on cavernous sinus hemangioma and to analyze the temporal volume change.

Cho et al. retrospectively reviewed the clinical data of 26 cavernous sinus hemangioma patients who were treated with GKS between 2001 and 2017. Before GKS, 11 patients (42.3%) had cranial neuropathies and 5 patients (19.2%) complained of headache, whereas 10 patients (38.5%) were initially asymptomatic. The mean pre-GKS mass volume was 9.3 mL (range, 0.5-31.6 mL), and the margin dose ranged from 13 to 15 Gy according to the mass volume and the proximity to the optic pathway. All cranial neuropathy patients and half of headache patients showed clinical improvement. All 26 patients achieved mass control; remarkable responses (less than 1/3 of the initial mass volume) were shown in 19 patients (73.1%) and moderate responses (more than 1/3 and less than 2/3) in 7 patients (26.9%). The mean final mass volume after GKS was 1.8 mL (range, 0-12.6 mL). The mean mass volume at 6 months after GKS was 45% (range, 5-80%) compared to the mass volume before GKS and 21% (range, 0-70%) at 12 months. The higher radiation dose tended to induce more rapid and greater volume reduction. No treatment-related complication was observed during the follow-up period. GKS could be an effective and safe therapeutic strategy for CSCH. GKS induced very rapid volume reduction compared to other benign brain tumors 1).


An international multicenter study was conducted to review outcome data in 31 patients with CSH. Eleven patients had initial microsurgery before SRS, and the other 20 patients (64.5%) underwent Gamma Knife SRS as the primary management for their CSH. Median age at the time of radiosurgery was 47 years, and 77.4% of patients had cranial nerve dysfunction before SRS. Patients received a median tumor margin dose of 12.6 Gy (range 12-19 Gy) at a median isodose of 55%. RESULTS Tumor regression was confirmed by imaging in all 31 patients, and all patients had greater than 50% reduction in tumor volume at 6 months post-SRS. No patient had delayed tumor growth, new cranial neuropathy, visual function deterioration, adverse radiation effects, or hypopituitarism after SRS. Twenty-four patients had presented with cranial nerve disorders before SRS, and 6 (25%) of them had gradual improvement. Four (66.7%) of the 6 patients with orbital symptoms had symptomatic relief at the last follow-up. CONCLUSIONS Stereotactic radiosurgery was effective in reducing the volume of CSH and attaining long-term tumor control in all patients at a median of 40 months. The authors’ experience suggests that SRS is a reasonable primary and adjuvant treatment modality for patients in whom a CSH is diagnosed. 2).


Between August 2011 and April 2014, 7 patients with CSHs underwent GKS. GKS was performed as the sole treatment option in 5 patients, whilst partial resection had been performed previously in 1 patient and biopsy had been performed in 1 patient. The mean volume of the tumors at the time of GKS was 12.5±10.2 cm3 (range, 5.3-33.2 cm3), and the median prescription of peripheral dose was 14.0 Gy (range, 10.0-15.0 Gy). The mean follow-up period was 20 months (range, 6-40 months). At the last follow-up, the lesion volume had decreased in all patients, and all cranial neuropathies observed prior to GKS had improved. There were no radiation-induced neuropathies or complications during the follow-up period. GKS appears to be an effective and safe treatment modality for the management of CSHs 3).


A retrospective analysis of 7 patients with CS hemangiomas treated by GKS between 1993 and 2008. Data from 84 CS meningiomas treated during the same period were also analyzed for comparison. The patients underwent follow-up magnetic resonance imaging at 6-month intervals. Data on clinical and imaging changes after radiosurgery were analyzed.

Six months after GKS, magnetic resonance imaging revealed an average of 72% tumor volume reduction (range, 56%-83%). After 1 year, tumor volume decreased 80% (range, 69%-90%) compared with the pre-GKS volume. Three patients had > 5 years of follow-up, which showed the tumor volume further decreased by 90% of the original size. The average tumor volume reduction was 82%. In contrast, tumor volume reduction of the 84 cavernous sinus meningiomas after GKS was only 29% (P < .001 by Mann-Whitney U test). Before treatment, 6 patients had various degrees of ophthalmoplegia. After GKS, 5 improved markedly within 6 months. Two patients who suffered from poor vision improved after radiosurgery.

GKS is an effective and safe treatment modality for CS hemangiomas with long-term treatment effect. Considering the high risks involved in microsurgery, GKS may serve as the primary treatment choice for CS hemangiomas 4).


1)

Cho JM, Sung KS, Jung IH, Chang WS, Jung HH, Chang JH. Temporal Volume Change of Cavernous Sinus Cavernous Hemangiomas after Gamma Knife Surgery. Yonsei Med J. 2020 Nov;61(11):976-980. doi: 10.3349/ymj.2020.61.11.976. PMID: 33107242.
2)

Lee CC, Sheehan JP, Kano H, Akpinar B, Martinez-Alvarez R, Martinez-Moreno N, Guo WY, Lunsford LD, Liu KD. Gamma Knife radiosurgery for hemangioma of the cavernous sinus. J Neurosurg. 2017 May;126(5):1498-1505. doi: 10.3171/2016.4.JNS152097. Epub 2016 Jun 24. PMID: 27341049.
3)

Xu Q, Shen J, Feng Y, Zhan R. Gamma Knife radiosurgery for the treatment of cavernous sinus hemangiomas. Oncol Lett. 2016 Feb;11(2):1545-1548. doi: 10.3892/ol.2015.4053. Epub 2015 Dec 23. PMID: 26893777; PMCID: PMC4734249.
4)

Chou CW, Wu HM, Huang CI, Chung WY, Guo WY, Shih YH, Lee LS, Pan DH. Gamma knife surgery for cavernous hemangiomas in the cavernous sinus. Neurosurgery. 2010 Sep;67(3):611-6; discussion 616. doi: 10.1227/01.NEU.0000378026.23116.E6. PMID: 20647963.

Cerebellopontine Angle Synchronous Tumor

Cerebellopontine Angle Synchronous Tumor

Synchronous cerebellopontine angle (CPA) tumors are a rare entity, heterogeneous lesions with a marked predisposition toward poor facial nerve outcomes, potentially attributable to a paracrine mechanism that simultaneously drives multiple tumor growth and increases invasiveness or adhesiveness at the facial nerve-tumor interface. Preceding nomenclature has been confounding and inconsistent; Graffeo et al. recommended classifying all multiple CPA tumors as “synchronous tumors,” with “schwannoma with meningothelial hyperplasia” or “tumor-to-tumor metastases” reserved for rare, specific circumstances 1).

Several publications refer to surgery for such tumors and their classification. Yet, there are no publications on upfront radiosurgery for synchronous CPA tumors.

Simultaneous and stepwise radiosurgery for synchronous CPA tumors seems to be safe and effective. There were no side effects or complications. To the best of our knowledge this is the first report on upfront radiosurgery for synchronous CPA tumors 2).

Mindermann and Heckl presented two patients with sporadic synchronous benign CPA tumors who underwent upfront radiosurgery. One patient had two separate schwannomas of the CPA and the other had a cerebellopontine angle schwannoma and a cerebellopontine angle meningioma. One patient underwent stepwise radiosurgery treating one tumor after another and the other patient underwent simultaneous radiosurgery for both tumors at the same time.

Simultaneous and stepwise radiosurgery for synchronous CPA tumors seems to be safe and effective. There were no side effects or complications. To the best of our knowledge this is the first report on upfront radiosurgery for synchronous CPA tumors 3).


A 64-year-old woman and a 42-year-old man presented with symptoms referable to the CPA. Magnetic resonance imaging in both patients revealed 2 separate contiguous tumors. Retrosigmoid craniotomy and tumor removal in each case confirmed VS and meningioma. Systematic literature review identified 42 previous English-language publications describing 46 patients with multiple CPA tumors. Based on Frassanito criteria, there were 4 concomitant tumors (8%), 16 contiguous tumors (33%), 3 collision tumors (6%), 13 mixed tumors (27%), and 11 tumor-to-tumor metastases (23%). Extent of resection was gross total in 16 cases and subtotal in 16 cases (50% each). Unfavorable House-Brackmann grade III-VI function was documented in 27% overall and in 33% of patients with VS and meningioma, a marked increase from the observed range in isolated VS 4).


A 57-year-old female patient presented with headache, speech disturbance, left facial numbness and deafness in the left ear. Magnetic resonance imaging demonstrated two different tumors in the left CPA. These tumors were not in continuity. The tumors were totally removed through the left suboccipital approach. Histopathological examination revealed that the large tumor was a vestibular schwannoma and the smaller was a meningioma. Neurofibromatosis was not diagnosed in the patient. No recurrence was observed at the end of 9 years after the operation. The simultaneous occurrence of vestibular schwannoma and meningioma in the CPA appears coincidental. This association must be kept in mind if two different tumors are detected radiologically in the same CPA 5).


1) , 4)

Graffeo CS, Perry A, Copeland WR 3rd, Giannini C, Neff BA, Driscoll CL, Link MJ. Synchronous Tumors of the Cerebellopontine Angle. World Neurosurg. 2017 Feb;98:632-643. doi: 10.1016/j.wneu.2016.11.002. Epub 2016 Nov 12. PMID: 27836701.
2) , 3)

Mindermann T, Heckl S. Radiosurgery for Sporadic Benign Synchronous Tumors of the Cerebellopontine Angle. J Neurol Surg A Cent Eur Neurosurg. 2020 Oct 21. doi: 10.1055/s-0040-1714424. Epub ahead of print. PMID: 33086420.
5)

Izci Y, Secer HI, Gönül E, Ongürü O. Simultaneously occurring vestibular schwannoma and meningioma in the cerebellopontine angle: case report and literature review. Clin Neuropathol. 2007 Sep-Oct;26(5):219-23. doi: 10.5414/npp26219. PMID: 17907598.
WhatsApp WhatsApp us
%d bloggers like this: