Stereotactic Gamma Knife surgery safety and efficacy in the management of symptomatic benign confined cavernous sinus meningioma

Recovery of cranial nerve neuropathies after LINAC-based stereotactic radiosurgery for benign cavernous sinus meningioma

PURPOSE

Cranial Nerve Neuropathies (CNNs) often accompany Cavernous Sinus Meningioma (CSM), for which Stereotactic Radiosurgery (SRS) or fractionated stereotactic radiotherapy (FSR) are established treatments. This study assesses CNNs recovery in CSM patients treated with LINAC, offering insight into treatment effectiveness.

METHODS

This study was conducted on 128 patients with CSM treated with LINAC-based SRS/FSR between 2005 and 2020 at a single institution. 46 patients presented with CNNs. The study analyzed patients' demographics, clinical parameters, SRS/FSR treatment characteristics, post-treatment CNNs recovery duration, status, and radiological control on their last follow-up.

RESULTS

The median follow-up duration was 53.4 months. Patients were treated with SRS (n = 25) or FSR (n = 21). The mean pretreatment tumor volume was 9.5 cc decreasing to a mean end-of-follow-up tumor volume was 5.1 cc. Radiological tumor control was achieved in all cases. CNN recovery was observed in 80.4% of patients, with specific nerve recoveries documented as follows: extra-ocular nerves (43.2%), trigeminal nerve (32.4%), and optic nerve (10.8%). A higher CNNs recovery rate was associated with a smaller pre-treatment tumor volume (p < 0.001), and the median time-to-improvement was 3.7 months. Patients with tumor volumes exceeding 6.8 cc and those treated with FSR exhibited prolonged time-to-improvement (P < 0.03 and P < 0.04 respectively).

CONCLUSIONS

This study suggests that SRS/FSR for CSM provides good and sustainable CNNs recovery outcomes with excellent long-term radiological control. A higher CNNs recovery rate was associated with a smaller pre-treatment tumor volume. while shorter time-to-improvement was identified in patients treated with SRS compared to FSR, particularly in those with small pre-treatment tumor volume.

Angiographic Evaluation of the Feeding Artery in Skull Base Meningioma

To identify the characteristics of feeding arteries in skull base meningioma including location and prevalence, we evaluated the distributions and types of feeding arteries in skull base meningioma by cerebral angiography and assessed relationships to tumor attachment. We enrolled patients with skull base meningioma who underwent MRI and cerebral digital subtraction angiography (DSA), from September 2015 to October 2022. Subjects comprised 115 patients (32 males, 83 females; mean age, 52.7) with 117 meningiomas, showing tumor attachments around the "cavernous sinus to the upper part of the clivus" (Area 1), "lower part of the clivus to foramen magnum" (Area 2), and "tentorium around the petrous bone" (Area 3). Frequent arteries, such as the dorsal meningeal artery (DMA), the ascending pharyngeal artery (APA), the tentorial artery (TA), and the petrosal branch (PB) of the middle meningeal artery (MMA) were analyzed in terms of their associations with tumor attachment to Areas 1-3. Meningiomas with the DMA as a feeding artery correlated with tumor attachment to Area 1 (p < 0.001). Meningiomas with the APA correlated with tumor attachment to Area 2 (p < 0.001). Meningiomas with the TA correlated with tumor attachment to Area 3 (p < 0.001). The PB correlated with Area 3 (p < 0.05). Our study founded that visualization of these arteries correlated well with specific areas. These arteries were also the main feeders in each type of skull base meningioma.

Target volume delineation for radiotherapy of meningiomas: an ANOCEF consensus guideline

PURPOSE

Radiotherapy is, with surgery, one of the main therapeutic treatment strategies for meningiomas. No prospective study has defined a consensus for the delineation of target volumes for meningioma radiotherapy. Therefore, target volume definition is mainly based on information from retrospective studies that include heterogeneous patient populations. The aim is to describe delineation guidelines for meningioma radiotherapy as an adjuvant or definitive treatment with intensity-modulated radiation therapy and stereotactic radiation therapy techniques. This guideline is based on a consensus endorsed by a multidisciplinary group of brain tumor experts, members of the Association of French-speaking Neuro-oncologists (ANOCEF).

MATERIALS AND METHODS

A 3-step procedure was used. First, the steering group carried out a comprehensive review to identify divergent issues on meningiomas target volume delineation. Second, an 84-item web-questionnaire has been developed to precisely define meningioma target volume delineation in the most common clinical situations. Third, experts members of the ANOCEF were requested to answer. The first two rounds were completed online. A third round was carried out by videoconference to allow experts to debate and discuss the remaining uncertain questions. All questions remained in a consensus.

RESULTS

Limits of the target volume were defined using visible landmarks on computed tomography and magnetic resonance imaging, considering the pathways of tumor extension. The purpose was to develop clear and precise recommendations on meningiomas target volumes.

CONCLUSION

New recommendations for meningiomas delineation based on simple anatomic boundaries are proposed by the ANOCEF. Improvement in uniformity in target volume definition is expected.

Single-Fraction Gamma-Knife Radiosurgery with or without Previous Surgery for Cavernous Sinus Meningiomas: A Single-Center Experience and Systematic Literature Review

Background

The most effective treatment method for meningiomas is surgical treatment. However, complete resection of cavernous sinus meningiomas is quite difficult. The biggest reasons for this are; narrow surgical corridor, the optic chiasm is the close relationship between the cranial nerves and anterior cerebral and internal carotid arteries. Gamma knife radiosurgery (GKRS) may be a good option in these lesions with high mortality and morbidity.

Aim

This study aimed to evaluate and compare the early effects at a mean of 6 months and 3 years and outcomes between surgery followed by gamma knife radiosurgery (GKRS) and GKRS alone for cavernous sinus meningiomas.

Methods

We included 20 patients with cavernous sinus meningioma treated via single fraction Leksell Gamma Knife Perfexion (Elekta Instruments; Stockholm, Sweden) between 2015 and 2018. The mean age of the patients was 54.95 (range: 32-77) years. Nine patients underwent primary surgery (for the resection of extracavernous components of the tumor) followed by GKRS (for the resection of intracavernous components of the tumor) (group A). Meanwhile, 11 patients were managed with GKRS alone (group B). The tumor volume ranged from 2.8 to 32.8 (mean: 14.76) cm3 and the isodose to the tumor margin from 10 to 13.5 (mean: 11.65) Gy.

Results

In total, 20 patients were followed up at a mean time of 18.95 (range: 6-36) months. The mean Karnofsky Performance Score of the patients was 95.2%. The mean follow up times of groups A and B were 23.6 and 15 months, respectively. Meanwhile, only patients with a follow up time of at least 6 months were included in the study. The mean follow up time after GKRS in group A was 17.6 months. There was no change in the tumor volume in 15% of patients. In the remaining cases, the tumor volume decreased. The mean tumor regression rates were 82.2% in Group A and 17.7% in Group B. The tumor volume did not decrease in three patients (n = 1, group A and n = 2, group B). Cranial nerve deficits improved, worsened, and remained stable in 46.6%, 26.6%, and 26.6% of cases, respectively. The temporary morbidity rate was 10%. In group A, transient postoperative diabetes insipidus was observed in one patient and atelectasis in another. None of these complications affected the final status of patients. The mortality rate after treatment was 0%.

Conclusion

Volume staged GKRS is safe and effective for cavernous sinus meningioma. GKRS is effective for long term tumor growth control and has a low complication rate. Hence, it is the preferred management strategy for tumors with a suitable volume (average tumor diameter: 3 cm or volume: 10 cm3 ). In tumors with a volume of more than 10 mL and/or without a 3 mm safety margin with the optical system, it is recommended to prepare for radiosurgery by cytoreducing the tumor volume surgically. Based on our opinion, the best results were obtained by GKRS to the intracavernous.

A radiomics-based study for differentiating parasellar cavernous hemangiomas from meningiomas

To investigate the value of the radiomic models for differentiating parasellar cavernous hemangiomas from meningiomas and to compare the classification performance with different MR sequences and classifiers. A total of 96 patients with parasellar tumors (40 cavernous hemangiomas and 56 meningiomas) were enrolled in this retrospective multiple-center study. Univariate and multivariate analyses were performed to identify the clinical factors and semantic features of MRI scans. Radiomics features were extracted from five MRI sequences using radiomics software. Three feature selection methods and six classifiers were evaluated in the training cohort to construct favorable radiomic machine-learning classifiers. The performance of different classifiers was evaluated using the AUC and compared to neuroradiologists. The detection rates of T1WI, T2WI, and CE-T1WI for parasellar cavernous hemangiomas and meningiomas were approximately 100%. In contrast, the ADC maps had the detection rate of 18/22 and 19/25, respectively, (AUC, 0.881) with 2.25 cm as the critical value diameter. Radiomics models with the SVM and KNN classifiers based on T2WI and ADC maps had favorable predictive performances (AUC > 0.90 and F-score value > 0.80). These models outperformed MRI model (AUC 0.805) and neuroradiologists (AUC, 0.756 and 0.545, respectively). Radiomic models based on T2WI and ADC and combined with SVM and KNN classifiers have the potential to be a viable method for differentiating parasellar hemangiomas from meningiomas. T2WI is more universally applicable than ADC values due to its higher detection rate for parasellar tumors.

Volumetric growth rates of untreated cavernous sinus meningiomas

OBJECTIVE

Meningiomas that arise primarily within the cavernous sinus are often believed to be more indolent in their growth pattern. Despite this perceived growth pattern, disabling symptoms can arise even with small tumors. While research has been done on cavernous sinus meningiomas (CSMs) and their treatment, very little is known about their natural growth rates. With a better understanding of the growth rate of CSM, patient treatment and guidance can be can optimized and individualized. The goal of this study was to determine volumetric growth rates of untreated CSMs.

METHODS

Thirty-seven patients with 166 MR images obtained between May 2004 and September 2019 were reviewed, with a range of 2-13 MR images per patient (average of 4.5 MR images per patient). These scans were obtained over an average follow-up period of 45.9 months (median 33.8, range 2.8-136.9 months). All imaging prior to any intervention was included in this analysis. Volumetric measurements were performed and assessed over time.

RESULTS

The estimated volumetric growth rate was 23.3% per year (95% CI 10.2%-38.0%, p < 0.001), which is equivalent to an estimated volume doubling time (VDT) of 3.3 years (95% CI 2.1-7.1 years). There was no significant relationship between growth rate and patient age (p = 0.09) or between growth rate and patient sex (p = 0.78). The median absolute growth rate was 41% with a range of -1% to 1793%. With a definition of "growth" as an increase of greater than 20% during the observed period, 65% of tumors demonstrated growth within their observation interval. Growth rates for each tumor were calculated and tumors were segmented based on growth rate. Of 37 patients, 22% (8) demonstrated no growth (< 5% annual growth, equivalent to a VDT > 13.9 years), 32% (12) were designated as slow growth (annual growth rate 5%-20%, VDT 3.5-13.9 years), 38% (14) were found to have medium growth (annual growth rate 20%-100%, VDT 0.7-3.5 years), and 8% were considered fast growing (annual growth rate > 100%, VDT < 0.7 years).

CONCLUSIONS

This study evaluated CSM volumetric growth rates. A deeper understanding of the natural history of untreated CSMs allows for better counseling and management of patients.

Meningiomas

Meningiomas arise in various locations. Convexity tumors are relatively simple to remove. Skull base tumors and tumors adjacent to the major cerebral veins and venous sinuses can be very difficult to extirpate. Attempts at radical resection can lead to serious morbidity. The combination of bulk reduction using microsurgery followed by GKNS gives greatly improved survival and very low morbidity. With smaller tumors, GKNS may be used as the primary treatment. Increasing numbers of asymptomatic meningiomas are demonstrated either as an unexpected finding or as a residual or recurrent tumor after surgery. In all of these situations, GKNS gives a better result than observation or reoperation.

Long-term outcomes of stereotactic radiosurgery for skull base tumors involving the cavernous sinus

PURPOSE

Stereotactic radiosurgery (SRS) is an effective and less invasive therapeutic option for cavernous sinus (CS) tumors. However, its long-term effectiveness and neurological outcomes have yet to be fully elucidated. We aimed to examine the long-term outcomes of SRS for CS tumors.

METHODS

Overall, a cohort of 113 patients with benign CS tumors, including 91 with meningioma, 14 with trigeminal schwannoma (TS), and eight with cavernous hemangioma, treated with SRS at our institution from 1990 to 2018, was included. Tumor control and functional preservation/recovery were evaluated in detail.

RESULTS

The median post-SRS follow-up period was 77 months (interquartile range, 39-177). Progression-free survival (PFS) was 97% at 5 years, 89% at 10 years, and 87% at 15 years for the entire cohort; 96% at 5 years and 87% at 10 years for meningiomas; and 100% at 10 years for the other tumors. No significant difference was observed between meningiomas and non-meningiomas (log-rank test, p = 0.107). Improvement in cranial nerve (CN) function was observed in 35 (27%) patients. TSs tended to show CN improvements more often than meningiomas did (total improvements, 62% vs. 23%; p = 0.004; eye movement function, 100% vs. 20%; p = 0.002). CN deterioration or development of new CN deficits was observed in 11 (10%) patients.

CONCLUSION

SRS provides good tumor control and acceptable long-term outcome with sufficient preservation of CN function in patients with benign CS tumors.

Management of cavernous sinus meningiomas: Consensus statement on behalf of the EANS skull base section

Introduction

The evolution of cavernous sinus meningiomas (CSMs) might be unpredictable and the efficacy of their treatments is challenging due to their indolent evolution, variations and fluctuations of symptoms, heterogeneity of classifications and lack of randomized controlled trials. Here, a dedicated task force provides a consensus statement on the overall management of CSMs.

Research question

To determine the best overall management of CSMs, depending on their clinical presentation, size, and evolution as well as patient characteristics.

Material and methods

Using the PRISMA 2020 guidelines, we included literature from January 2000 to December 2020. A total of 400 abstracts and 77 titles were kept for full-paper screening.

Results

The task force formulated 8 recommendations (Level C evidence). CSMs should be managed by a highly specialized multidisciplinary team. The initial evaluation of patients includes clinical, ophthalmological, endocrinological and radiological assessment. Treatment of CSM should involve experienced skull-base neurosurgeons or neuro-radiosurgeons, radiation oncologists, radiologists, ophthalmologists, and endocrinologists.

Discussion and conclusion

Radiosurgery is preferred as first-line treatment in small, enclosed, pauci-symptomatic lesions/in elderly patients, while large CSMs not amenable to resection or WHO grade II-III are candidates for radiotherapy. Microsurgery is an option in aggressive/rapidly progressing lesions in young patients presenting with oculomotor/visual/endocrinological impairment. Whenever surgery is offered, open cranial approaches are the current standard. There is limited experience reported about endoscopic endonasal approach for CSMs and the main indication is decompression of the cavernous sinus to improve symptoms. Whenever surgery is indicated, the current trend is to offer decompression followed by radiosurgery.

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A thorough evaluation of cavernous sinus meningiomas by a multidisciplinary team is mandatory.

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Microsurgery should be considered for aggressive lesions in young patients.

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Extended endoscopic approaches can be effective when combined with radiotherapy.

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Stereotaxic radiotherapy and stereotaxic radiosurgery offer excellent tumour control in small/asymptomatic lesions .

STA-MCA Bypass in Carotid Stenosis after Radiosurgery for Cavernous Sinus Meningioma

BACKGROUND

Cavernous sinus meningiomas (CSM) are mostly non-surgical tumors. Stereotactic radiosurgery (SRS) or radiotherapy (SRT) allow tumor control and improvement of pre-existing cranial nerve (CN) deficits. We report the case of a patient with radiation-induced internal carotid artery (ICA) stenosis. We complete the picture with a review of the literature of vascular and non-vascular complications following the treatment of CSMs with SRS or SRT.

METHODS

After a case description, a systematic literature review is presented, according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2015 guidelines.

RESULTS

115 abstracts were screened and 70 titles were retained for full-paper screening. A total of 58 articles did not meet the inclusion criteria. There were 12 articles included in our review, with a follow-up ranging from 33 to 120 months. Two cases of post-SRT ischemic stroke and one case of asymptomatic ICA stenosis were described. Non-vascular complications were reported in all articles.

CONCLUSION

SRS and SRT carry fewer complications than open surgery, with similar rates of tumor control. Our case shows the importance of a follow-up of irradiated CSMs not only by a radio-oncologist, but also by a neurosurgeon, illustrating the importance of multidisciplinary management of CSMs.

Successful management of an intraluminal superior sagittal sinus meningioma causing elevated intracranial pressure using gamma knife radiosurgery in subacute setting: A case report

Background:

Gamma Knife stereotactic radiosurgery (GKRS) facilitates precisely focused radiation to an intracranial target while minimizing substantial off-target radiation in the surrounding normal tissue. Meningiomas attached to or invading the superior sagittal sinus may result in sinus occlusion and are often impossible to completely resect safely. The authors describe successful management of a patient with a meningioma located completely inside the posterior aspect of the superior sagittal sinus.

Case Description:

A 46-year-old woman presented to the emergency department with progressive generalized headaches accompanied by worsening vision. The patient underwent a diagnostic brain magnetic resonance imaging which showed a solitary a 7 × 6 × 10 mm homogeneously contrast-enhancing lesion within the lumen of the posterior aspect of superior sagittal sinus without ventricular enlargement or peritumoral edema. The lesion was thought to be a meningioma radiographically. To evaluate the suspected increased intracranial pressure, a lumbar puncture was subsequently performed and demonstrated an opening pressure of 30 cm H2O. After drainage of 40 cc of CSF, the spinal closing pressure was 9 cm H2O. After failure of conservative management with acetazolamide, and determination of surgical inoperability due to the critical intraluminal location of the mass lesion, the patient underwent Gamma Knife radiosurgery. The 0.36 cc tumor was treated as an outpatient in the Perfexion® model Gamma Knife with a highly conformal and selective plan that enclosed the 3D geometry of the tumor with a minimal margin tumor dose of 14 gy at the 50% isodose. Three months after GKRS, the patient reported continued reduction in the frequency and severity of both her headaches and her visual disturbance. Ophthalmological consultation noted progressive resolution of her optic disc edema confirmed by formal optical coherence tomography. The patient is now 3 years out from GKRS with complete resolution of headache symptoms along with persistent reduction in tumor size (3 × 1 × 4 mm) on serial period imaging and resolution of papilledema.

Conclusion:

Tumors located in such critical anatomic regions, as in our patient, should be considered for primary GKRS when the risks of biopsy or removal are too high. GKRS was able to provide great radiographic and clinical result in an intricately located meningioma.

Gamma Knife radiosurgery for intracranial benign meningiomas: follow-up outcome in 130 patients

OBJECTIVEThe authors retrospectively analyzed the follow-up data in 130 patients with intracranial benign meningiomas after Gamma Knife radiosurgery (GKRS), evaluated the tumor progression-free survival (PFS) rate and neurological function preservation rate, and determined the predictors by univariate and multivariate survival analysis.METHODSThis cohort of 130 patients with intracranial benign meningiomas underwent GKRS between May 2012 and May 2015 at the Second Hospital of Tianjin Medical University. The median age was 54.5 years (range 25-81 years), and women outnumbered men at a ratio of 4.65:1. All clinical and radiological data were obtained for analysis. No patient had undergone prior traditional radiotherapy or chemotherapy. The median tumor volume was 3.68 cm3 (range 0.23-45.78 cm3). A median margin dose of 12.0 Gy (range 10.0-16.0 Gy) was delivered to the tumor with a median isodose line of 50% (range 50%-60%).RESULTSDuring a median follow-up of 36.5 months (range 12-80 months), tumor volume regressed in 37 patients (28.5%), was unchanged in 86 patients (66.2%), and increased in 7 patients (5.4%). The actuarial tumor progression-free survival (PFS) rate was 98%, 94%, and 87% at 1, 3, and 5 years, respectively, after GKRS. Tumor recurred in 7 patients at a median follow-up of 32 months (range 12-56 months). Tumor volume ≥ 10 cm3 (p = 0.012, hazard ratio [HR] 8.25, 95% CI 1.60-42.65) and pre-GKRS Karnofsky Performance Scale score < 90 (p = 0.006, HR 9.31, 95% CI 1.88-46.22) were independent unfavorable predictors of PFS rate after GKRS. Of the 130 patients, 101 (77.7%) presented with one or more neurological symptoms or signs before GKRS. Neurological symptoms or signs improved in 40 (30.8%) patients, remained stable in 83 (63.8%), and deteriorated in 7 (5.4%) after GKRS. Two (1.5%) patients developed new cranial nerve (CN) deficit. Tumor volume ≥ 10 cm3 (p = 0.042, HR = 4.73, 95% CI 1.06-21.17) and pre-GKRS CN deficit (p = 0.045, HR = 4.35, 95% CI 0.84-22.48) were independent unfavorable predictors for improvement in neurological symptoms or signs. Six (4.6%) patients developed new or worsening peritumoral edema with a median follow-up of 4.5 months (range 2-7 months).CONCLUSIONSGKRS provided good local tumor control and high neurological function preservation in patients with intracranial benign meningiomas. Patients with tumor volume < 10 cm3, pre-GKRS Karnofsky Performance Scale score ≥ 90, and no pre-GKRS CN deficit (I-VIII) can benefit from stereotactic radiosurgery. It can be considered as the primary or adjuvant management of intracranial benign meningiomas.

Efficacy and Tolerance of Intensity Modulated Radiation Therapy for Skull Base Meningioma

Purpose

The purpose of this study was to evaluate the efficacy and tolerance of normofractionated stereotactic radiation therapy (RT) and intensity modulated RT with helical tomotherapy for skull base meningioma.

Methods and Materials

Between January 2009 and 2014, 46 patients with skull base meningioma were treated with normofractionated intensity modulated RT in stereotactic conditions (50%) or with helical tomotherapy (50%). Most of the lesions were localized in the cavernous sinus (59%). The mean planning target volume was 47.2 mL (range, 1.1-223 mL).

Results

After treatment, 5 lesions exhibited a partial response radiologically and 39 lesions were stable. At the time of treatment, 35 patients were symptomatic with a mean of 2 symptoms per patient. The most frequent symptoms were visual impairment (41%), cranial nerve dysfunction (20%), and headache (16%). The median follow-up time was 42 months (range, 10-76 months). After RT, 71% of patients exhibited an improvement of at least 1 symptom with a median interval of 15.6 months (range, 5.3-30.5 months). The most frequent improved symptoms were cranial nerve deficits (47%), visual impairment (45%), and headache (42%).The clinical response was correlated with the clinical target volume (CTV) margin (P = .06), extended clinical follow-up time (P = .004), and larger planning target volume (P = .05) by univariate analysis. Taking in account correlation factors, in the multivariate analysis, only CTV was a favorable significant factor of clinical improvement (P = .049; hazard ratio: 5 95%; confidence interval, 1.1-28). We observed 3 cases of trigeminal nerve dysfunction at 4.2, 5.7, and 24.6 months; 2 cases of visual disturbance at 10.1 and 24 months; 2 cases of neurocognitive disorders at 12.9 and 35.2 months; and 1 case of stroke at 20.3 months.

Conclusions

RT for skull base meningiomas is an effective and safe treatment, leading in most cases to clinical improvement. The addition of a CTV margin to meningioma volume improved the symptoms of patients.

Gamma Knife stereotactic radiosurgery for cavernous sinus meningioma: long-term follow-up in 200 patients

OBJECTIVE

The authors of this study evaluate the long-term outcomes of stereotactic radiosurgery (SRS) for cavernous sinus meningioma (CSM).

METHODS

The authors retrospectively assessed treatment outcomes 5-18 years after SRS in 200 patients with CSM. The median patient age was 57 years (range 22-83 years). In total, 120 (60%) patients underwent Gamma Knife SRS as primary management, 46 (23%) for residual tumors, and 34 (17%) for recurrent tumors after one or more surgical procedures. The median tumor target volume was 7.5 cm3 (range 0.1-37.3 cm3), and the median margin dose was 13.0 Gy (range 10-20 Gy).

RESULTS

Tumor volume regressed in 121 (61%) patients, was unchanged in 49 (25%), and increased over time in 30 (15%) during a median imaging follow-up of 101 months. Actuarial tumor control rates at the 5-, 10-, and 15-year follow-ups were 92%, 84%, and 75%, respectively. Of the 120 patients who had undergone SRS as a primary treatment (primary SRS), tumor progression was observed in 14 (11.7%) patients at a median of 48.9 months (range 4.8-120.0 months) after SRS, and actuarial tumor control rates were 98%, 93%, 85%, and 85% at the 1-, 5-, 10-, and 15-year follow-ups post-SRS. A history of tumor progression after microsurgery was an independent predictor of an unfavorable response to radiosurgery (p = 0.009, HR = 4.161, 95% CI 1.438-12.045). Forty-four (26%) of 170 patients who had presented with at least one cranial nerve (CN) deficit improved after SRS. Development of new CN deficits after initial microsurgical resection was an unfavorable factor for improvement after SRS (p = 0.014, HR = 0.169, 95% CI 0.041-0.702). Fifteen (7.5%) patients experienced permanent CN deficits without evidence of tumor progression at a median onset of 9 months (range 2.3-85 months) after SRS. Patients with larger tumor volumes (≥ 10 cm3) were more likely to develop permanent CN complications (p = 0.046, HR = 3.629, 95% CI 1.026-12.838). Three patients (1.5%) developed delayed pituitary dysfunction after SRS.

CONCLUSIONS

This long-term study showed that Gamma Knife radiosurgery provided long-term tumor control for most patients with CSM. Patients who underwent SRS for progressive tumors after prior microsurgery had a greater chance of tumor growth than the patients without prior surgery or those with residual tumor treated after microsurgery.

[Skull base meningioma: Clinical and radiological efficacy based on a quantitative volumetric analysis]

PURPOSE

To date, no correlation has been found between clinical and radiological efficacy after irradiation of skull base meningiomas. However, the evaluation of the radiological response was most often made by questionable methods that may have underestimated the radiological effectiveness of radiotherapy. The objective of this work is to verify this hypothesis by quantitative volumetric analysis.

MATERIAL AND METHODS

Data from 35 patients treated with either helical tomotherapy (45.7%) or fractionated stereotactic radiotherapy (54.3%) were retrospectively analysed. These were mainly women (94%) aged 59 (43-81) with lesions mainly of the cavernous sinus (60%). There was a median of 2 (1-4) symptoms and the main symptoms were visual impairment (39%), cranial nerve deficits (23.4%) and headaches (17.2%).

RESULTS

Median tumour volume decreased significantly (P<0.05) from 9.6mL (0.3-36.6) to 6.8mL (0.1-26.5) after median follow-up of 44 months (24-77). Sixty-three percent of patients had an improvement of at least one symptom. In univariate analysis, clinical efficacy (P<0.05), radiotherapy technique (P<0.05), tumor topography (P<0.05) and initial tumor volume (P<0.05) were predictive factors for radiological response. In multivariate analysis, only the inverse correlation between radiological response and initial tumor volume remained significant (ρ: -0.47 95% CI -3.2 to 5.7; P<0.05).

CONCLUSION

The quantitative volumetric monitoring demonstrates a major radiological efficiency of radiotherapy. However, no clear correlation between clinical and radiological efficacy was found.

Stereotactic Radiosurgery of Cavernous Sinus Meningiomas

Objective  Microsurgical resection of cavernous sinus meningiomas (CSM) is associated with a high rate of incomplete resection, recurrence, and the risk for permanent, severe cranial nerve deficits. Stereotactic radiosurgery (SRS) has evolved as alternative treatment for primary and recurrent CSM. Here, we report about the long-term clinical and radiological follow-up (FU) of a unique cohort of patients with CSM treated with LINAC or Cyberknife based SRS. Methods  In this single-center retrospective analysis, we include all patients with CSM who underwent single fraction SRS between 1993 and 2016. Clinical and radiological tumor control were evaluated by the Kaplan-Meier method. Additionally, patient data were analyzed in terms of symptom control and incidence of side effects rated by the common terminology criteria for adverse events (CTCAE; v4.03). Results  116 patients (female/male = 91/25; median age, 54 years; range, 33-82 years) were included. Mean tumor volume was 5.7 ± 3.3 cm ³ (range, 0.6-16.2 cm ³ ), the median marginal dose was 12.6 Gy applied to isodose levels of 75%. Median clinical FU was 55 months (range, 3-226 months). Tumor control was 98% after 2 and 5 years and 90% after 10 years. Twelve patients (10.3%) had permanent or transient radiation related toxicity (CTCAE I-III). An improvement of symptoms was observed in 26.7% of the symptomatic patients ( n  = 20 of 75). Conclusion  SRS for CSM provides excellent long-term tumor and symptom control without considerable permanent side effects. Thus, SRS should be considered when counseling patients suffering from CSM.

Natural history of cavernous sinus meningiomas

OBJECTIVE

Meningiomas confined to the cavernous sinus (MCSs) are benign tumors. Due to the high risk of severe complications, the intracavernous surgical procedure was abandoned in favor of radiotherapy. However, the choice of treatment remains complicated due to the fact that the natural history of this lesion has not yet been described.

METHODS

The authors studied the natural history of this lesion using a prospective series of 53 consecutive patients suffering from MCSs. The median follow-up duration was 10.2 years (range 2-25 years), from 1990 to 2016.

RESULTS

Patients ranged in age from 30 to 72 years (mean 53 years). The meningiomas were diagnosed by major symptoms (mainly oculomotor palsy and neuralgia experienced in 28 patients), minor symptoms (headache, intermittent diplopia in 15 patients), or incidental findings (10 patients). Simple symptomatic treatment (short courses of corticosteroids and carbamazepine) allowed patients to become asymptomatic in 19 (67.9%) of 28 cases experiencing major symptoms, and for 12 (80%) of 15 patients with initial minor symptoms (p < 0.0001). All patients with incidental findings remained asymptomatic. Forty four (83%) of 53 MCSs did not show any significant growth and 42 (80%) of 53 patients were not symptomatic at the end of follow-up (p < 0.001). The radiographic progression-free survival rates (± SD) at 5, 10, and 20 years were 90% ± 4.2%, 82% ± 5.7%, and 70% ± 10.2%, respectively. Five patients (9.4%) with no evidence of any effect of the initial medical treatment desired additional conventional radiation therapy.

CONCLUSIONS

Because of the capricious, unpredictable, and slow growth of MCSs, together with high growth variability from one patient to the next, the symptomatic medical treatment of these tumors is a highly effective method. This series shows that these lesions are naturally, clinically, and radiologically indolent.

Radiosurgery and fractionated radiotherapy for cavernous sinus meningioma: a systematic review and meta-analysis

INTRODUCTION

Radiosurgery (RS) and fractionated radiotherapy (FRT) are part of the therapeutic armamentarium for the management of cavernous sinus meningiomas. We propose a systematic review of the local tumor control and clinical outcomes after monofractionated radiosurgical treatment, including gamma knife radiosurgery (GKRS) and linear accelerator (Linac RS), or fractionated radiotherapy.

MATERIALS AND METHODS

The current review and meta-analysis adhered to the PRISMA guidelines. We performed a search in PubMed, Embase, and Medline based on the following mesh terms, used alone or in diverse combinations, in both title and abstract: "cavernous sinus," "meningioma," "radiosurgery," "gamma knife," "linac," "cyberknife," and "radiotherapy". We screened 425 studies. We selected 36 studies, matching all selection criteria: 24 for GK, 5 for Linac, and 7 for FRT.

RESULTS

Were included 2817 patients (GKRS, n = 2047, LinacRS, n = 350, FRT, n = 420). Half of patients benefited from upfront RS or FRT; the other half benefited from adjuvant RS or FRT (combined approach or tumor recurrence). The mean gross target volume (GTV) was smaller for RS as compared to FRT (p = 0.07). The median marginal doses were 13.9 Gy (range, 11 to 28) for GKRS and 14 Gy (range, 12.8 to 17.7) for LinacRS. For FRT, patients received a mean dose of 51.2 Gy (25.5 fractions, 1.85 Gy each). The mean overall follow-up values were 48 months (range, 15 to 89) for GKRS, 69 months (range, 46 to 87) for Linac, and 59.5 months (range, 33 to 83) for FRT. PFS at 5 years for GKRS, LinacRS, and FRT were respectively 93.6%, 95.6%, and 97.4% (p = 0.32, the Kruskal-Wallis). Monofractionated treatments (GKRS and LinacRS) induced more tumor volume regression than FRT (p = 0.001). Tumor recurrence or progression ranged between 3 and 5.8%, without statistically significant differences between modalities (p > 0.05). Trigeminal symptoms improved in approximately 54%, and III-IV-VI cranial nerves (CN) palsies improved in approximately 45%. After GKRS, visual acuity improved in 21% (not enough data available for other modalities). De novo deficits occurred in 5 to 7.5%. Adverse radiation effects appeared in 4.6 to 9.3% (all techniques pooled).

CONCLUSION

RS achieved a twice-higher rate of tumor volume regression than FRT. GKRS series reported an improvement in visual acuity in 21% of the cases. GKRS, Linac, and FRT provided similar clinical post therapeutic outcomes for the trigeminal and oculomotor CN.

[Base of the skull meningioma: Efficacy, clinical tolerance and radiological evaluation after radiotherapy]

Skull base meningioma leads to functional disturbances, which can significantly alter the quality of life. The optimal management of these lesions, whose goals are neurological preservation and tumour local control, is not yet clearly established. It is widely recognized that the goal of a radical excision should be abandoned despite the advances in the field of microsurgery of skull base lesions. Although less morbid, partial tumour excision would be associated with increased risk of local tumour recurrence. Although discussed both exclusive and adjuvant have proven to be highly successful in terms of clinical improvement and local control. Various radiation techniques have demonstrated their efficacy in the management of this pathology. However, high rates of clinical improvement are in contrast with low rates of radiological improvement. The notion of clinical and radiological dissociation appeared. However, in most of these studies, the analysis of the radiological response could be subject of legitimate criticism. This work proposes to review the local control, the efficacy and the clinical tolerance and the radiological response of the various radiation techniques for the meningioma of the base of the skull and to demonstrate the interest of quantitative volumetric analyses in the follow-up of meningioma after radiotherapy.

Safety and efficacy of single-fraction gamma knife radiosurgery for benign confined cavernous sinus tumors: our experience and literature review

Gamma knife radiosurgery (GKRS) has emerged as a suitable primary treatment option for confined cavernous sinus tumors (CSTs) and residual/recurrent benign tumors extending from the surrounding neighborhood. The aim of this review was to further investigate the safety and efficacy of single-fraction GKRS for primary confined CSTs (hemangioma, meningioma, and schwannoma). This was a retrospective analysis of 16 patients of CSTs, primarily treated with GKRS between 2009 and 2017. The patients underwent follow-up clinical and radiological evaluation at a regular interval. Data on clinical and imaging parameters were analyzed. The published literature on GKRS for CSTs was reviewed. There were total 16 patients (eight meningiomas, seven hemangiomas, and one schwannoma). Patients presented with a headache (56.3%), ptosis (50%), and/or restricted extraocular movements (50%). There was 46.6% tumor volume (TV) reduction after single-fraction GKRS. Hemangiomas showed best TV reduction (64% reduction at > 3-year follow-up) followed by schwannoma (41.5%) and meningioma (25.4%). 56.3% of patients developed transient hypoesthesia in trigeminal nerve distribution. 44.4% of patients became completely pain-free. Among cranial nerves, the superior division of the oculomotor nerve showed best outcome (ptosis 62.5%) followed by an improved range of EOM. There was no adverse event in the form of new-onset deficit, vascular complication, or malignant transformation except for one out of the field failures. Among available treatment options, GKRS is the most suitable option by virtue of its minimally invasive nature, optimal long-term tumor control, improvement in cranial neuropathies, cost-effectiveness, favorable risk-benefit ratio, and minimal long-term complications.

Safe maximal resection of primary cavernous sinus meningiomas via a minimal anterior and posterior combined transpetrosal approach

OBJECTIVE

Meningiomas arising from the cavernous sinus (CS) continue to be a significant technical challenge, and resection continues to carry a relatively higher risk of neurological morbidity in patients with these lesions because of the tumor’s proximity to neurovascular structures. The authors report the surgical outcomes of 9 patients with primary CS meningiomas (CSMs) that were surgically treated using a minimal anterior and posterior combined (MAPC) transpetrosal approach, and they emphasize the usefulness of the approach.

METHODS

This retrospective study included 9 patients who underwent surgery for CSM treatment between 2015 and 2016 via the MAPC transpetrosal approach. Two patients were men and 7 were women, with a mean age of 58.5 years (39–72 years). Five patients (55.5%) had undergone previous treatment. The surgical technique consisted of a temporo-occipito-suboccipital craniotomy and exposure of the posterolateral part of the CS via the presigmoidal MAPC approach. After opening Meckel’s cave and identifying the 3rd–5th cranial nerves in the prepontine cistern, Parkinson’s triangle and supratrochlear triangles were opened. Finally, the tumor occupying the posterolateral part of the CS was removed.

RESULTS

All lesions were safely and maximally removed, with preservation of external ocular movements and preoperative Karnofsky Performance Scale scores. The mean extent of resection was 77.0% (range 58.7%–95.4%). Six patients underwent adjuvant therapy in the form of stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT) during the follow-up period; none of these patients experienced recurrence.

CONCLUSION

The authors conclude that the MAPC transpetrosal approach could be superior to other approaches for CSMs, as it provides direct visual access to the posterolateral portion of the CS. In their experience, this approach is an alternative and better option for safe maximal resection of CSMs.