Factors Influencing Long-Term Outcomes of Single-Session Gamma Knife Radiosurgery in Large-Volume Meningiomas >10 cc.

INTRODUCTION: Meningiomas are the most common primary intracranial tumour. Gamma knife radiosurgery (GKRS) is a frequently employed non-invasive method of treatment, with good remission rates and low morbidity in literature. However, the role of GKRS in the management of "large" meningiomas is unclear, with reported outcomes that vary by centre. We aimed to assess the factors that influence long-term outcomes following GKRS in meningiomas >10 cc in volume. METHODS: A retrospectively analysed all patients with meningiomas exceeding 10 cc in volume who underwent GKRS between January 2006 and December 2021 at the National Institute of Mental Health and Neurosciences (NIMHANS), Bengaluru. Demographic, clinical, radiological, and follow-up data were acquired, and factors associated with progression following GKRS were assessed. RESULTS: The cohort comprised 76 patients 29 males (38.2%) and 47 females (61.8%) with a mean age of 46.3 ± 11.02 years. Thirty-nine patients had been previously operated (51.3%). Meningiomas were most frequently located in the parasagittal region (26 tumours, 34.2%) and sphenopetroclival region (23 tumours, 30.3%), with mean lesion volume of 12.55 ± 5.22 cc, ranging 10.3 cc-25 cc. The mean dose administered to the tumour margin was 12.5 Gy ± 1.2 Gy (range 6-15 Gy). The median duration of clinical follow-up was 48 months, over which period radiological progression occurred in 14 cases (20%), with unchanged tumour volume in 20 cases (28.6%) and reduction in size of the tumour in 36 cases (51.4%). Progression-free survival after GKRS was 72% at 5 years, was significantly poorer among meningiomas with tumour volume >14 cc (log-rank test p = 0.045), tumours presenting with limb motor deficits (log-rank test p = 0.012), and tumours that underwent prior Simpson grade 3 or 4 excision (log-rank test p = 0.032). CONCLUSIONS: Meningiomas >10 cc in volume appear to display a high rate of progression and subsequent need for surgery following GKRS. Primary surgical resection, when not contraindicated, may be considered with GKRS serving an adjuvant role, especially in tumours exceeding 14 cc in volume, and presenting with limb motor deficits. Long-term clinical and radiological follow-up is essential following GKRS as the response of large meningiomas may be unpredictable.

Upfront stereotactic radiosurgery versus adjuvant radiosurgery for parasagittal and parafalcine meningiomas: a systematic review and meta-analysis.

Parafalcine and parasagittal (PFPS) are common locations for meningiomas. Surgical resection for these tumors, the first-line treatment, poses challenges due to their proximity to critical structures. This systematic review investigates the use of stereotactic radiosurgery (SRS) as a treatment for PFPS meningiomas, aiming to elucidate its safety and efficacy. The review adhered to PRISMA guidelines. Searches were conducted on MEDLINE, Embase, and Cochrane. Inclusion criteria involved studies on SRS for PFPS meningiomas, reporting procedure outcomes and complications. Tumors were presumed or confirmed to be WHO grade 1. Data was systematically extracted. Meta-analysis was performed where applicable. The review included data from eight studies, 821 patients with 878 lesions. Tumor control was achieved in greater than 80% of cases. Adverse radiation effects were reported in 7.3% of them. Recurrence and further surgical approach were observed in 17.1% and 9.2% of cases, respectively. Symptom improvement was noted in 33.2% of patients. Edema occurred in approximately 25.1% of patients. A subgroup of 283 patients had upfront SRS, achieving tumor control in approximately 97% of such cases. SRS is a safe and effective treatment for PFPS meningiomas, both as an adjuvant therapy and as an upfront treatment for often smaller tumors. Post-SRS edema can typically be managed medically and usually does not require further surgical intervention. Further studies should provide more specific data on PFPS meningiomas. The use of single and hypofractionated SRS for larger volume PFPS meningiomas should be more explored to better define the risks and benefits.

Ki-67 labeling index predicts tumor progression patterns and survival in patients with atypical meningiomas following stereotactic radiosurgery.

PURPOSE: This study investigated whether Ki-67 labeling index (LI) correlated with clinical outcomes after SRS for atypical meningiomas. METHODS: This retrospective study examined 39 patients with atypical meningiomas who underwent SRS over a 10-year study period. Ki-67 LI was categorized into 3 groups: low (< 5%), intermediate (5%-10%), and high (> 10%). Local tumor control rates (LCRs), progression-free rates (PFRs), disease-specific survival (DSS) rates, and adverse radiation-induced events (AREs) were evaluated. RESULTS: The median follow-up periods were 26 months. SRS was performed at a median prescription dose of 18 Gy for tumors with a median Ki-67 LI of 9.6%. The 3-year LCRs were 100%, 74%, and 25% in the low, intermediate, and high LI groups, respectively (p = 0.011). The 3-year PFRs were 100%, 40%, and 0% in the low, intermediate, and high LI groups (p = 0.003). The 5-year DSS rates were 100%, 89%, and 50% in the low, intermediate, and high LI groups (p = 0.019). Multivariable Cox proportional hazard analysis showed a significant correlation of high LI with lower LCR (hazard ratio [HR], 3.92; 95% confidence interval [CI] 1.18-13.04, p = 0.026), lower PFR (HR 3.80; 95% CI 1.46-9.88, p = 0.006), and shorter DSS (HR 6.55; 95% CI 1.19-35.95, p = 0.031) compared with intermediate LI. The ARE rates were minimal (8%) in the entire group. CONCLUSION: Patients with high Ki-67 LI showed significantly more tumor progression and tumor-related death. Ki-67 LI might offer valuable predictive insights for the post-SRS management of atypical meningiomas.

Surgical Outcome of Torcula Herophili Meningioma: An Institutional Experience.

INTRODUCTION: Resection of meningiomas (THMs) at the torcular Herophili poses challenges to surgeons due to complex regional anatomy. The current study aims to evaluate factors affecting the extent of resections, progression-free survival, and the role of radiation. METHODS: We did a retrospective study of all the THM patients treated at our institute between May 1987 and June 2022. The demographic data, signs and symptoms, surgical notes, postoperative details, and radiotherapy were gathered retrospectively. Survival analysis was done with Kaplan-Meier tests along with predictors of the extent of resection as well as recurrence. RESULTS: A total of 39 patients qualified to be included in the study, with 10 male patients (male:female 1:2.9) and an average age of 50.8 years. The average follow-up duration was 75.9 months. Simpson's grade 2 excision was achieved in 19 (48.7%) patients, followed by Simpson's grade 3 excision in 17 patients (43.6%). Progression-free survival in subtotal resection was 60 months, and 100 months in gross total resection. Statistically, the extent of the resection was determined by the involvement of sinuses/torcula and the number of quadrants involved around torcula. A total of 16 patients received radiosurgery for the residual or small reccurrence of the lesion. Follow-up revealed reccurrence in 5 cases. CONCLUSIONS: Torcular meningiomas are relatively uncommon, described in few reports, and represent a therapeutic dilemma. Though some experts recommend complete removal of tumor and reconstruction of the sinus, others suggest maximum safe resection, followed by radiosurgery. The present study reflects reasonable control of the residual lesion with radiosurgery after maximum safe resection.

Adjuvant Stereotactic Radiosurgery for Clear Cell Meningiomas.

OBJECTIVE: Clear cell meningiomas (CCM) are an uncommon meningioma subtype marked by aggressive growth and high rates of recurrence despite initial resection. The present study evaluates the adjuvant benefit of stereotactic radiosurgery (SRS) for residual or recurrent tumors. METHODS: After review of our prospectively maintained database, we identified 6 patients (3 female) with histologically confirmed Grade 2 CCMs. The median age of the patients at the time of SRS was 45 years. Five patients had undergone prior gross total surgical resection and 1 patient had subtotal resection before SRS. The median SRS treatment volume was 4.7 cc and the median radiosurgical margin dose was 13 Gy (range: 10-15 Gy). RESULTS: The median follow-up time was 35.5 months (range 6-168 months). Three patients achieved tumor control after the first SRS procedure. Three patients experienced tumor progression at 4, 22, and 32 months after initial SRS. Tumor control was obtained in 2 of these patients after additional SRS. One patient with multiple SRS procedures had suspected adverse radiation effect that was successfully treated with corticosteroids followed by bevacizumab. CONCLUSIONS: Tumor control was maintained in 5 of 6 patients after one or more SRS procedures. SRS should be considered for early intervention after surgical resection of CCM. To maximize the tumor control rate, patients with diagnosed CCM should be treated more generously and higher margin dose should be prescribed. Patients with CCM should be counselled that more than one SRS may be necessary to provide sustained tumor control.

Radiolabeled Somatostatin Receptor Antagonist Versus Agonist for Peptide Receptor Radionuclide Therapy in Patients with Therapy-Resistant Meningioma: PROMENADE Phase 0 Study.

Our primary aim was to compare the therapeutic index (tumor-to-bone marrow and tumor-to-kidney absorbed-dose ratios) of the new radiolabeled somatostatin receptor antagonist [177Lu]Lu-DOTA-JR11 with the established radiolabeled somatostatin receptor agonist [177Lu]Lu-DOTATOC in the same patients with progressive, standard therapy-refractory meningioma. Methods: In this prospective, single-center, open-label phase 0 study (NCT04997317), 6 consecutive patients were included: 3 men and 3 women (mean age, 63.5 y). Patients received 6.9-7.3 GBq (standard injected radioactivity) of [177Lu]Lu-DOTATOC followed by 3.3-4.9 GBq (2 GBq/m2 × body surface area) of [177Lu]Lu-DOTA-JR11 at an interval of 10 ± 1 wk. In total, 1 [177Lu]Lu-DOTATOC and 2-3 [177Lu]Lu-DOTA-JR11 treatment cycles were performed. Quantitative SPECT/CT was done at approximately 24, 48, and 168 h after injection of both radiopharmaceuticals to calculate meningioma and organ absorbed doses as well as tumor-to-organ absorbed-dose ratios (3-dimensional segmentation approach for meningioma, kidneys, liver, bone marrow, and spleen). Results: The median of the meningioma absorbed dose of 1 treatment cycle was 3.4 Gy (range, 0.8-10.2 Gy) for [177Lu]Lu-DOTATOC and 11.5 Gy (range, 4.7-22.7 Gy) for [177Lu]Lu-DOTA-JR11. The median bone marrow and kidney absorbed doses after 1 treatment cycle were 0.11 Gy (range, 0.05-0.17 Gy) and 2.7 Gy (range, 1.3-5.3 Gy) for [177Lu]Lu-DOTATOC and 0.29 Gy (range, 0.16-0.39 Gy) and 3.3 Gy (range, 1.6-5.9 Gy) for [177Lu]Lu-DOTA-JR11, resulting in a 1.4 (range, 0.9-1.9) times higher median tumor-to-bone marrow absorbed-dose ratio and a 2.9 (range, 2.0-4.8) times higher median tumor-to-kidney absorbed-dose ratio with [177Lu]Lu-DOTA-JR11. According to the Common Terminology Criteria for Adverse Events version 5.0, 2 patients developed reversible grade 2 lymphopenia after 1 cycle of [177Lu]Lu-DOTATOC. Afterward, 2 patients developed reversible grade 3 lymphopenia and 1 patient developed reversible grade 3 lymphopenia and neutropenia after 2-3 cycles of [177Lu]Lu-DOTA-JR11. No grade 4 or 5 adverse events were observed at 15 mo or more after the start of therapy. The disease control rate was 83% (95% CI, 53%-100%) at 12 mo or more after inclusion. Conclusion: Treatment with 1 cycle of [177Lu]Lu-DOTA-JR11 showed 2.2-5.7 times higher meningioma absorbed doses and a favorable therapeutic index compared with [177Lu]Lu-DOTATOC after injection of 1.4-2.1 times lower activities. The first efficacy results demonstrated a high disease control rate with an acceptable safety profile in the standard therapy for refractory meningioma patients. Therefore, larger studies with [177Lu]Lu-DOTA-JR11 are warranted in meningioma patients.

Gamma knife radiosurgery as primary management for intracranial meningioma identified as growing on serial imaging.

Gamma knife radiosurgery (GKRS) has emerged as a highly effective therapeutic modality for the management of intracranial meningiomas. However, the role of GKRS in treating growing meningiomas detected during active surveillance remains unclear. This study seeks to investigate the long-term outcomes of GKRS treatment for growing meningiomas. A retrospective analysis was conducted on patients who underwent GKRS as the primary treatment for growing meningiomas between 2004 and 2021. Growing meningiomas were defined as those exhibiting a > 10% increase in tumor volume (TV) compared to the previous imaging. Fifty-nine patients who received GKRS as their initial treatment were included, with a minimum follow-up period of 12 months. Comprehensive clinical, radiological, and procedural data were analyzed. Serial TV assessments were performed for all tumors before and after GKRS. Tumor progression and regression were defined as a > 10% increase or decrease in TV, respectively, compared to the pretreatment image. At a median follow-up of 41 months (range 15-197 months), TV was unchanged in 16 patients (27.1%), decreased in 41 patients (69.5%), and increased in 2 patients (3.4%). Multivariate analysis revealed that both TV (cm3) (hazard ratio [HR], 1.107; 95% confidence interval [CI], 1.002-1.222; P = .045) and volume growing rate (%/yr) (HR, 1.013; 95% CI, 1.000-1.025; P = .04) significantly correlated with tumor progression. Eleven patients (18.6%) experienced new or worsening symptoms. In multivariate analysis, factor predicting new or worsening neurological function was preexisting calcification (HR, 5.297; 95% CI, 1.328-21.124; P = .018). GKRS demonstrates a promising level of tumor control with minimal risk of neurological deterioration when applied to growing meningiomas. These findings provide compelling support for considering GKRS as a valuable therapeutic option following an initial period of active surveillance for these tumors.

Trends in Stereotactic Radiosurgery for Meningioma: the Top 100 Most Cited Articles.

BACKGROUND: Stereotactic radiosurgery is a well-known and influential management option for meningioma. This article aims to highlight the most cited publications on this topic. METHODS: All Scopus articles published in English under Stereotactic radiosurgery and meningioma were sorted according to the number of citations. The keywords used were: "Stereotactic radiosurgery, SRS, Meningioma, Intracranial meningioma". The top 100 cited articles meeting the criteria were included. Certain features of these articles were collected and analyzed using Microsoft Excel and SPSS. RESULTS: The included articles were published between 1991 and 2020 with a total of 9149 citations. The most cited article is "Meningiomas: Knowledge base, treatment outcomes, and uncertainties. A RANO review" by Rogers L. et al. 2015 with 349 citations. No significant association was found between the number of citations and the impact factor of the publishing journal. CONCLUSION: This study gives a concise and updated summary of impactful research on stereotactic radiosurgery and meningioma, highlighting the main contributors and scientific connections.

Patterns of failure after radiosurgery for WHO grade 1 or imaging defined meningiomas: Long-term outcomes and implications for management.

BACKGROUND: We analyzed long-term control and patterns of failure in patients with World Health Organization Grade 1 meningiomas treated with definitive or postoperative stereotactic radiosurgery at the authors' affiliated institution. METHODS: 96 patients were treated between 2004 and 2019 with definitive (n = 57) or postoperative (n = 39) stereotactic radiosurgery. Of the postoperative patients, 17 were treated adjuvantly following subtotal resection and 22 were treated as salvage at time of progression. Patients were treated to the gross tumor alone without margin or coverage of the dural tail to a median dose of 15 Gy. Median follow up was 7.4 years (inter-quartile range 4.8-11.3). Local control, marginal control, regional control, and progression-free survival were analyzed. RESULTS: Local control at 5 and 10 years was 97 % and 95 %. PFS at 5 and 10 years was 94 % and 90 % with no failures reported after 6 years. Definitive and postoperative local control were similar at 5 (95 % [82-99 %] vs. 100 %) and 10 years (92 % [82-99 %] vs. 100 %). Patients treated with postoperative SRS did not have an increased marginal failure rate (p = 0.83) and only 2/39 (5 %) experienced recurrence elsewhere in the cavity. CONCLUSIONS: Stereotactic radiosurgery targeting the gross tumor alone provides excellent local control and progression free survival in patients treated definitively and postoperatively. As in the definitive setting, patients treated postoperatively can be treated to gross tumor alone without need for additional margin or dural tail coverage.

Evaluation of the SSTR2-targeted Radiopharmaceutical 177Lu-DOTATATE and SSTR2-specific 68Ga-DOTATATE PET as Imaging Biomarker in Patients with Intracranial Meningioma.

PURPOSE: There are no effective medical therapies for patients with meningioma who progress beyond surgical and radiotherapeutic interventions. Somatostatin receptor type 2 (SSTR2) represents a promising treatment target in meningiomas. In this multicenter, single-arm phase II clinical study (NCT03971461), the SSTR2-targeting radiopharmaceutical 177Lu-DOTATATE is evaluated for its feasibility, safety, and therapeutic efficacy in these patients. PATIENTS AND METHODS: Adult patients with progressive intracranial meningiomas received 177Lu-DOTATATE at a dose of 7.4 GBq (200 mCi) every eight weeks for four cycles. 68Ga-DOTATATE PET-MRI was performed before and six months after the start of the treatment. The primary endpoint was progression-free survival (PFS) at 6 months (PFS-6). Secondary endpoints were safety and tolerability, overall survival (OS) at 12 months (OS-12), median PFS, and median OS. RESULTS: Fourteen patients (female = 11, male = 3) with progressive meningiomas (WHO 1 = 3, 2 = 10, 3 = 1) were enrolled. Median age was 63.1 (range 49.7-78) years. All patients previously underwent tumor resection and at least one course of radiation. Treatment with 177Lu-DOTATATE was well tolerated. Seven patients (50%) achieved PFS-6. Best radiographic response by modified Macdonald criteria was stable disease (SD) in all seven patients. A >25% reduction in 68Ga-DOTATATE uptake (PET) was observed in five meningiomas and two patients. In one lesion, this corresponded to >50% reduction in bidirectional tumor measurements (MRI). CONCLUSIONS: Treatment with 177Lu-DOTATATE was well tolerated. The predefined PFS-6 threshold was met in this interim analysis, thereby allowing this multicenter clinical trial to continue enrollment. 68Ga-DOTATATE PET may be a useful imaging biomarker to assess therapeutic outcome in patients with meningioma.

A Prospective Registry Study of 68Ga-DOTATATE PET/CT Incorporation Into Treatment Planning of Intracranial Meningiomas.

PURPOSE: The current standard for meningioma treatment planning involves magnetic resonance imaging-based guidance. Somatostatin receptor ligands such as 68Ga-DOTATATE are being explored for meningioma treatment planning due to near-universal expression of somatostatin receptors 1 and 2 in meningioma tissue. We hypothesized that 68Ga-DOTATATE positron emission tomography (PET)-guided treatment management for patients with meningiomas is safe and effective and can identify which patients benefit most from adjuvant radiation therapy. METHODS AND MATERIALS: A single-institution prospective registry study was created for inclusion of patients with intracranial meningiomas who received a 68Ga-DOTATATE PET/CT to assist with radiation oncologist decision making. Patients who received a PET scan from January 1, 2018, to February 25, 2022, were eligible for inclusion. RESULTS: Of the 60 patients included, 40%, 47%, and 5% had World Health Organization grades 1, 2, and 3 meningiomas, respectively, and 8% (5 patients) had no grade assigned. According to Radiation Therapy Oncology Group 0539 criteria, 22%, 72%, and 7% were categorized as high, intermediate, and low risk, respectively. After completing their PET scans, 48 patients, 11 patients, and 1 patient proceeded with radiation therapy, observation, and redo craniotomy, respectively. The median follow-up for the entire cohort was 19.5 months. Of the 3 patients (5%) who experienced local failure between 9.2 and 28.5 months after diagnosis, 2 had PET-avid disease in their postoperative cavity and elected for observation before recurrence, and 1 high-risk patient with multifocal disease experienced local failure 2 years after a second radiation course and multiple previous recurrences. Notably, 5 patients did not have any local PET uptake and were observed; none of these patients experienced recurrence. Only 1 grade 3 toxicity was attributed to PET-guided radiation. CONCLUSIONS: This study examined one of the largest known populations of patients with intracranial meningiomas followed by physicians who used 68Ga-DOTATATE PET-guided therapy. Incorporating 68Ga-DOTATATE PET into future trials may assist with clinician decision making and improve patient outcomes.

Characteristics and outcomes for 61 cats that underwent either surgery or stereotactic radiotherapy as treatment for intracranial meningioma (2005-2017).

OBJECTIVE: To report clinical features and outcomes of cats undergoing either stereotactic radiotherapy (SRT) or surgical excision for the treatment of intracranial meningioma. ANIMALS: 61 client-owned cats. METHODS: Medical records were retrospectively reviewed of cats with intracranial meningiomas that were treated with surgical removal and/or SRT between 2005 and 2017. Signalment, clinical signs, duration of clinical signs, diagnostic imaging reports, histopathology reports, treatment protocol, complications, recurrence or progression, and survival time were obtained from the medical record and through follow-up phone calls. RESULTS: Of the 61 patients, 46 had surgery, 14 had SRT, and 1 had surgery followed by SRT for initial treatment. Significantly more cats that underwent surgery had peritreatment complications compared to the SRT group (P < .0001). Cats that received surgery initially had a significantly longer median survival time (MST) of 1,345 days compared to the MST of 339 days for the SRT cats (P = .002). Fourteen (30%) cats in the surgery group and 4 cats in the SRT group (28%) had MRI- or CT-confirmed tumor regrowth or new tumor growth (P = 1.00). Five cases that had SRT for subsequent recurrence had an MST of 700 days (range, 335 to 1,460 days) after the last treatment. CLINICAL RELEVANCE: SRT proved to be a safe, alternative treatment option for feline patients with intracranial meningiomas; however, the survival times with surgery alone were significantly longer. SRT for the treatment of recurrence following initial surgery may show promising results.

Trigeminal neuralgia pain outcomes following microsurgical resection versus stereotactic radiosurgery for petroclival meningiomas: a systematic review and meta-analysis.

OBJECTIVE: Petroclival meningiomas (PCMs) are challenging lesions to treat because of their deep location and proximity to critical neurovascular structures. Patients with these lesions commonly present because of local mass effect. A symptom that proves challenging to definitively manage is trigeminal neuralgia (TN), which occurs in approximately 5% of PCM cases. To date, there is no consensus on whether microsurgical resection or stereotactic radiosurgery (SRS) leads to better outcomes in the treatment of TN secondary to PCM. In this systematic review and meta-analysis, the authors aimed to evaluate the available literature on the efficacy of microsurgical resection versus SRS for controlling TN secondary to PCM. METHODS: The Embase, MEDLINE, Scopus, and Cochrane databases were queried from database inception to May 17, 2022, using the search terms "(petroclival AND meningioma) AND (trigeminal AND neuralgia)." Study inclusion criteria were as follows: 1) reports on patients aged ≥ 18 years and diagnosed with TN secondary to PCM, 2) cases treated with microsurgical resection or SRS, 3) cases with at least one posttreatment follow-up report of TN pain, 4) cases with at least one outcome of tumor control, and 5) publications describing randomized controlled trials, comparative or single-arm observational studies, case reports, or case series. Exclusion criteria were 1) literature reviews, technical notes, conference abstracts, or autopsy reports; 2) publications that did not clearly differentiate data on patients with PCMs from data on patients with different tumors or with meningiomas in different locations (other intracranial or spinal meningiomas); 3) publications that contained insufficient data on treatments and outcomes; and 4) publications not written in the English language. References of eligible studies were screened to retrieve additional relevant studies. Data on pain and tumor outcomes were compared between the microsurgical resection and SRS treatment groups. The DerSimonian-Laird random-effects model with Hartung-Knapp-Sidik-Jonkman variance correction was used to pool estimates from the included studies. RESULTS: Two comparative observational studies and 6 single-arm observational studies describing outcomes after primary intervention were included in the analyses (138 patients). Fifty-seven patients underwent microsurgical resection and 81 underwent SRS for the management of TN secondary to PCM. By the last follow-up (mean 71 months, range 24-149 months), the resection group had significantly higher rates of pain resolution than the SRS group (82%, 95% CI 50%-100% vs 31%, 95% CI 18%-45%, respectively; p = 0.004). There was also a significantly longer median time to tumor recurrence following resection (43.75 vs 16.7 months, p < 0.01). The resection group showed lower rates of pain persistence (0%, 95% CI 0%-6% vs 25%, 95% CI 13%-39%, p = 0.001) and pain exacerbation (0% vs 12%, 95% CI 3%-23%, p = 0.001). The most common postintervention Barrow Neurological Institute pain score in the surgical group was I (66.7%) compared with III (27.2%) in the SRS group. Surgical reintervention was less frequently required following primary resection (1.8%, 95% CI 0%-37% vs 19%, 95% CI 1%-48%, p < 0.01). CONCLUSIONS: Microsurgical resection is associated with higher rates of TN pain resolution and lower rates of pain persistence and exacerbation than SRS in the treatment of PCM. SRS with further TN management is a viable alternative in patients who are not good candidates for microsurgical resection.

Dose-Escalated Radiation Therapy Is Associated With Improved Outcomes for High-Grade Meningioma.

PURPOSE: The optimal modern radiation therapy (RT) approach after surgery for atypical and malignant meningioma is unclear. We present results of dose escalation in a single-institution cohort spanning 2000 to 2021. METHODS AND MATERIALS: Consecutive patients with histopathologic grade 2 or 3 meningioma treated with RT were reviewed. A dose-escalation cohort (≥66 Gy equivalent dose in 2-Gy fractions using an α/ß = 10) was compared with a standard-dose cohort (<66 Gy). Outcomes were progression-free survival (PFS), cause-specific survival, overall survival (OS), local failure (LF), and radiation necrosis. RESULTS: One hundred eighteen patients (111 grade 2, 94.1%) were identified; 54 (45.8%) received dose escalation and 64 (54.2%) standard dose. Median follow-up was 45.4 months (IQR, 24.0-80.0 months) and median OS was 9.7 years (Q1: 4.6 years, Q3: not reached). All dose-escalated patients had residual disease versus 65.6% in the standard-dose cohort (P < .001). PFS at 3, 4, and 5 years in the dose-escalated versus standard-dose cohort was 78.9%, 72.2%, and 64.6% versus 57.2%, 49.1%, and 40.8%, respectively, (P = .030). On multivariable analysis, dose escalation (hazard ratio [HR], 0.544; P = .042) was associated with improved PFS, whereas ≥2 surgeries (HR, 1.989; P = .035) and older age (HR, 1.035; P < .001) were associated with worse PFS. The cumulative risk of LF was reduced with dose escalation (P = .016). Multivariable analysis confirmed that dose escalation was protective for LF (HR, 0.483; P = .019), whereas ≥2 surgeries before RT predicted for LF (HR, 2.145; P = .008). A trend was observed for improved cause-specific survival and OS in the dose-escalation cohort (P < .1). Seven patients (5.9%) developed symptomatic radiation necrosis with no significant difference between the 2 cohorts. CONCLUSIONS: Dose-escalated RT with ≥66 Gy for high-grade meningioma is associated with improved local control and PFS with an acceptable risk of radiation necrosis.

The treatment efficacy of radiotherapy for optic nerve sheath meningioma.

OBJECTIVES: Optic nerve sheath meningioma (ONSM) is a rare benign tumour that accounts for approximately 2% of all orbital tumours. Radiotherapy has gradually become an important treatment for ONSM because of its good effect in preserving or improving vision. We aimed to explore the effect of radiotherapy on tumour control and vision preservation/improvement in patients with ONSM. METHODS: Forty-three patients with primary ONSM treated in our institution from 2015 to 2021 were enrolled. The irradiation dose was from 50.4 to 54 Gy with 28-30 fractions. We evaluated the tumour volume on MRI or CT, and visual acuity before and after the radiotherapy. RESULTS: Thirty-four patients (79%) experienced a vision decrease at diagnosis. The mean duration of follow-up was 54.1 months (ranges: 18-93, median: 56). Among 25 patients who had tumour evaluation using MRI, 16 patients (37.2%) showed stable tumours, 7 patients (16.3%) had tumour shrinkage, but 2 patients (4.7%) experienced tumour progression. Among the 39 patients performing vision acuity evaluation, 16 patients (37.2%) had vision improvement or recovery. 16 of the 23 patients without vision improvement demonstrated severe visual loss at diagnosis. Two patients had evidence of tumour progression during the follow-up. Additionally, 4 (10.2%) patients had dry eyes, 7 (17.9%) patients experienced watery eyes, and 3 (7.7%) patients had eye swelling. Patients with vision loss for more than 12 months had a lower possibility of vision recovery than those with vision loss for less than 12 months. CONCLUSIONS: Radiotherapy such as IMRT, VMAT, and 3D-CRT plays an important role in the treatment of ONSM. The probability of vision recovery is lower in patients with severe vision loss at diagnosis or the duration of vision loss is more than 12 months.

Targeted gene expression profiling predicts meningioma outcomes and radiotherapy responses.

Surgery is the mainstay of treatment for meningioma, the most common primary intracranial tumor, but improvements in meningioma risk stratification are needed and indications for postoperative radiotherapy are controversial. Here we develop a targeted gene expression biomarker that predicts meningioma outcomes and radiotherapy responses. Using a discovery cohort of 173 meningiomas, we developed a 34-gene expression risk score and performed clinical and analytical validation of this biomarker on independent meningiomas from 12 institutions across 3 continents (N = 1,856), including 103 meningiomas from a prospective clinical trial. The gene expression biomarker improved discrimination of outcomes compared with all other systems tested (N = 9) in the clinical validation cohort for local recurrence (5-year area under the curve (AUC) 0.81) and overall survival (5-year AUC 0.80). The increase in AUC compared with the standard of care, World Health Organization 2021 grade, was 0.11 for local recurrence (95% confidence interval 0.07 to 0.17, P < 0.001). The gene expression biomarker identified meningiomas benefiting from postoperative radiotherapy (hazard ratio 0.54, 95% confidence interval 0.37 to 0.78, P = 0.0001) and suggested postoperative management could be refined for 29.8% of patients. In sum, our results identify a targeted gene expression biomarker that improves discrimination of meningioma outcomes, including prediction of postoperative radiotherapy responses.

Comparison of the efficacy in improving trigeminal neuralgia in petroclival meningioma between microsurgery and radiosurgery: a meta-analysis.

The purpose of this study was to systematically review studies in the literature to assess the superiority between microsurgery and radiosurgery regarding the efficacy in improving petroclival meningioma (PCM)-related trigeminal neuralgia (TN). PubMed, Embase, Web of Science, and Cochrane clinical trial databases were systematically searched from the inception until December 08, 2022. The overall proportion of patients with improved TN after treatment in all six included studies was 56% (95% confidence interval [CI], 35-76.9%). Higgins I2 statistics showed significant heterogeneity (I2 = 90%). Subgroup analysis showed that the proportion of improved TN was higher in the microsurgery group than that in the radiosurgery group (89%; 95% CI, 81-96.5% vs. 37%, 95% CI, 22-52.7%, respectively, p < 0.01). Subgroup analysis (for studies that documented the number of posttreatment Barrow Neurological Institute scores 1 and 2) revealed that the proportion of pain-free without medication after treatment was higher in the microsurgery group than that in the radiosurgery group (90.7%; 95% CI, 81-99.7% vs. 34.5%, 95% CI, 21.3-47.7.7%, respectively, p < 0.01). Based on the results of this meta-analysis, we concluded that microsurgery is superior to radiosurgery in controlling PCM-related TN.