Stereotactic radiosurgery versus active surveillance for asymptomatic, skull-based meningiomas: an international, multicenter matched cohort study.

OBJECTIVE: The optimal management of asymptomatic, skull-based meningiomas is not well defined. The aim of this study is to compare the imaging and clinical outcomes of patients with asymptomatic, skull-based meningiomas managed either with upfront stereotactic radiosurgery (SRS) or active surveillance. METHODS: This retrospective, multicenter study involved patients with asymptomatic, skull-based meningiomas. The study end-points included local tumor control and the development of new neurological deficits attributable to the tumor. Factors associated with tumor progression and neurological morbidity were also analyzed. RESULTS: The combined unmatched cohort included 417 patients. Following propensity score matching for age, tumor volume, and follow-up 110 patients remained in each cohort. Tumor control was achieved in 98.2% and 61.8% of the SRS and active surveillance cohorts, respectively. SRS was associated with superior local tumor control (p < 0.001, HR = 0.01, 95% CI = 0.002-0.13) compared to active surveillance. Three patients (2.7%) in the SRS cohort and six (5.5%) in the active surveillance cohort exhibited neurological deterioration. One (0.9%) patient in the SRS-treated and 11 (10%) patients in the active surveillance cohort required surgical management of their meningioma during follow-up. CONCLUSIONS: SRS is associated with superior local control of asymptomatic, skull-based meningiomas as compared to active surveillance and does so with low morbidity rates. SRS should be offered as an alternative to active surveillance as the initial management of asymptomatic skull base meningiomas. Active surveillance policies do not currently specify the optimal time to intervention when meningioma growth is noted. Our results indicate that if active surveillance is the initial management of choice, SRS should be recommended when radiologic tumor progression is noted and prior to clinical progression.

Stereotactic radiosurgery versus active surveillance for incidental, convexity meningiomas: a matched cohort analysis from the IMPASSE study.

BACKGROUND: The optimal treatment strategy of asymptomatic, convexity meningiomas, remains unclear. OBJECTIVE: The purpose of this study was to define the safety and efficacy of stereotactic radiosurgery (SRS) in the management of patients with asymptomatic convexity meningiomas. METHODS: Data of SRS-treated patients from 14 participating centers and patients managed conservatively for an asymptomatic, convexity-located meningioma were compared. Local tumor control rate and development of new neurologic deficits were evaluated in the active surveillance and in the SRS-treated cohorts. RESULTS: In the unmatched cohorts, there were 99 SRS-treated patients and 140 patients managed conservatively for an asymptomatic, convexity meningioma. Following propensity score matching for age, there were 98 patients in each cohort. In the matched cohorts, tumor control was achieved in 99% of SRS-treated, and in 69.4% of conservatively managed patients (p < 0.001). New neurological deficits occurred in 2.0% of patients in each of the matched cohorts (p = 1.00). Increasing age was predictive of tumor growth [(OR 1.1; 95% CI (1.04 - 1.2), (p < 0.001)]. CONCLUSION: This is one of the first reports to suggest that SRS is a low risk and effective treatment strategy for asymptomatic incidentally discovered convexity meningiomas. In this study, tumor control was achieved in significantly more patients after radiosurgery compared to those managed with active surveillance. SRS may be offered at diagnosis of an asymptomatic convexity meningioma and should be recommended when meningioma growth is noted on follow-up.

Stereotactic radiosurgery for asymptomatic petroclival region meningiomas: a focused analysis from the IMPASSE study.

BACKGROUND: The optimal management of asymptomatic, petroclival meningiomas remains incompletely defined. The purpose of this study was to evaluate the safety and efficacy of upfront stereotactic radiosurgery (SRS) for patients with asymptomatic, petroclival region meningiomas. METHODS: This retrospective, international, multicenter study involved patients treated with SRS for an asymptomatic, petroclival region meningioma. Study endpoints included local tumor control rate, procedural complications, and the emergence of new neurological deficits. RESULTS: There were 72 patients (22 males, mean age 59.53 years (SD ± 11.9)) with an asymptomatic meningioma located in the petroclival region who were treated with upfront SRS. Mean margin dose and maximum dose were 13.26 (SD ± 2.72) Gy and 26.14 (SD ± 6.75) Gy respectively. Median radiological and clinical follow-up periods post-SRS were 52.5 (IQR 61.75) and 47.5 months (IQR 69.75) respectively. At last follow-up, tumor control was achieved in all patients. SRS-related complications occurred in 6 (8.33%) patients, with 3 of them (4.17%) exhibiting new neurological deficits. CONCLUSIONS: Upfront SRS for asymptomatic, petroclival region meningiomas affords excellent local tumor control and does so with a relatively low risk of SRS-related complications. SRS can be considered at diagnosis of an asymptomatic petroclival region meningioma. If active surveillance is initially chosen, SRS should be recommended when growth is noted during radiological follow-up.

Stereotactic Radiosurgery for Incidentally Discovered Cavernous Sinus Meningiomas: A Multi-institutional Study.

BACKGROUND: The initial management of asymptomatic, incidentally discovered, cavernous sinus (CS) meningiomas remains incompletely defined. This study evaluated the safety and efficacy of stereotactic radiosurgery (SRS) for patients presenting with an asymptomatic CS meningioma. METHODS: This is an international, retrospective study included patients treated with upfront SRS for an asymptomatic CS meningioma. Local tumor control, tumor and SRS-related complications, and the development of new neurologic deficits after SRS were evaluated. RESULTS: A total of 37 patients (29 men; mean ± SD age: 55.05 ± 11.56 years) treated with upfront SRS for an asymptomatic, CS meningioma were included in the study. The mean ± SD margin dose was 12.27 ± 2.3 Gy. The median clinical and radiological follow-up periods were 66 (IQR 84) and 72 (IQR 84) months, respectively. At the last follow-up, tumor regression and stability were noted in 19 (51.35%) and 18 (48.65%) of CS meningiomas, respectively. SRS-related complications occurred in 2 patients (5.4%) and were managed conservatively. CONCLUSIONS: Upfront SRS is a safe and effective treatment option for asymptomatic CS meningiomas. SRS may be considered at the time of initial diagnosis of a CS meningioma. If observation is the initial management chosen, SRS should be recommended when CS meningioma growth is documented on follow-up imaging.

Comparison of Active Surveillance to Stereotactic Radiosurgery for the Management of Patients with an Incidental Frontobasal Meningioma-A Sub-Analysis of the IMPASSE Study.

Meningioma is a common incidental finding, and clinical course varies based on anatomical location. The aim of this sub-analysis of the IMPASSE study was to compare the outcomes of patients with an incidental frontobasal meningioma who underwent active surveillance to those who underwent upfront stereotactic radiosurgery (SRS). Data were retrospectively collected from 14 centres. The active surveillance (n = 28) and SRS (n = 84) cohorts were compared unmatched and matched for age, sex, and duration of follow-up (n = 25 each). The study endpoints included tumor progression, new symptom development, and need for further intervention. Tumor progression occurred in 52.0% and 0% of the matched active surveillance and SRS cohorts, respectively (p < 0.001). Five patients (6.0%) treated with SRS developed treatment related symptoms compared to none in the active monitoring cohort (p = 0.329). No patients in the matched cohorts developed symptoms attributable to treatment. Three patients managed with active surveillance (10.7%, unmatched; 12.0%, matched) underwent an intervention for tumor growth with no persistent side effects after treatment. No patients subject to SRS underwent further treatment. Active monitoring and SRS confer a similarly low risk of symptom development. Upfront treatment with SRS improves imaging-defined tumor control. Active surveillance and SRS are acceptable treatment options for incidental frontobasal meningioma.

Stereotactic Radiosurgery Compared With Active Surveillance for Asymptomatic, Parafalcine, and Parasagittal Meningiomas: A Matched Cohort Analysis From the IMPASSE Study.

BACKGROUND: The optimal management of asymptomatic, presumed WHO grade I meningiomas remains controversial. OBJECTIVE: To define the safety and efficacy of stereotactic radiosurgery (SRS) compared with active surveillance for the management of patients with asymptomatic parafalcine/parasagittal (PFPS) meningiomas. METHODS: Data from SRS-treated patients from 14 centers and patients managed conservatively for an asymptomatic, PFPS meningioma were compared. Local tumor control rate and new neurological deficits development were evaluated in the active surveillance and the SRS-treated cohorts. RESULTS: There were 173 SRS-treated patients and 98 patients managed conservatively in the unmatched cohorts. After matching for patient age and tumor volume, there were 98 patients in each cohort. The median radiological follow-up period was 43 months for the SRS cohort and 36 months for the active surveillance cohort (P = .04). The median clinical follow-up for the SRS and active surveillance cohorts were 44 and 36 months, respectively. Meningioma control was noted in all SRS-treated patients and in 61.2% of patients managed with active surveillance (P < .001). SRS-related neurological deficits occurred in 3.1% of the patients (n = 3), which were all transient. In the active surveillance cohort, 2% of patients (n = 2) developed neurological symptoms because of tumor progression (P = 1.0), resulting in death of 1 patient (1%). CONCLUSION: Up-front SRS affords superior radiological PFPS meningioma control as compared with active surveillance and may lower the risk of meningioma-related permanent neurological deficit and/or death.

An international multicenter matched cohort analysis of incidental meningioma progression during active surveillance or after stereotactic radiosurgery: the IMPASSE study.

BACKGROUND: The optimal management of patients with incidental meningiomas remains unclear. The aim of this study was to characterize the radiologic and neurological outcomes of expectant and stereotactic radiosurgery (SRS) management of asymptomatic meningioma patients. METHODS: Using data from 14 centers across 10 countries, the study compares SRS outcomes to active surveillance of asymptomatic meningiomas. Local tumor control of asymptomatic meningiomas and development of new neurological deficits attributable to the tumor were evaluated in the SRS and conservatively managed groups. RESULTS: In the unmatched cohorts, 727 meningioma patients underwent SRS and were followed for a mean of 57.2 months. In the conservatively managed cohort, 388 patients were followed for a mean of 43.5 months. Tumor control was 99.0% of SRS and 64.2% of conservatively managed patients (P < .001; OR 56.860 [95% CI 26.253-123.150]). New neurological deficits were 2.5% in the SRS and 2.8% of conservatively managed patients (P = .764; OR 0.890 [95% CI 0.416-1.904]). After 1:1 propensity matching for patient age, tumor volume, location, and imaging follow-up, tumor control in the SRS and conservatively managed cohorts was 99.4% and 62.1%, respectively (P < .001; OR 94.461 [95% CI 23.082-386.568]). In matched cohorts, new neurological deficits were noted in 2.3% of SRS-treated and 3.2% of conservatively managed patients (P = .475; OR 0.700 [95% CI 0.263-1.863]). CONCLUSIONS: SRS affords superior radiologic tumor control compared to active surveillance without increasing the risk of neurological deficits in asymptomatic meningioma patients. While SRS and active surveillance are reasonable options, SRS appears to alter the natural history of asymptomatic meningiomas including tumor progression in the majority of patients treated.

Stereotactic Radiosurgery for Olfactory Groove Meningiomas: An International, Multicenter Study.

BACKGROUND: Stereotactic radiosurgery (SRS) is increasingly considered for selected olfactory groove meningiomas (OGMs). OBJECTIVE: To investigate the safety and efficacy of SRS for OGMs. METHODS: From 20 institutions participating in the International Radiosurgery Research Foundation, we pooled patients who underwent SRS for histologically confirmed or radiologically suspected WHO grade I OGMs and were followed for 6 mo or more after the SRS. RESULTS: In total, 278 (median age 57 yr) patients underwent SRS for histologically confirmed (29%) or radiologically suspected (71%) WHO grade I OGMs Median treatment volume was 4.60 cm3 (range: 0.12-27.3 cm3), median prescription dose was 12 Gy, and median dose to the olfactory nerve was 11.20 Gy. During median post-SRS imaging follow-up of 39 mo (range: 6-240 mo), 43% of patients had partial or marginal response, 54% of patients had stable disease, and 3% of patients experienced progression. During median post-SRS clinical follow-up of 51 mo (range: 6-240 mo), 36 (13%) patients experienced clinical and/or radiological adverse radiation events (AREs). Elevated risk of AREs was associated with larger OGM volume (P = .009) and pre-SRS peritumoral T2/fluid-attenuated inversion-recovery signal abnormalities (P < .001). After the SRS, olfaction remained stable, improved, or deteriorated in 90%, 8%, and 2% of patients, respectively. Complete post-SRS anosmia was predicted by partial/complete anosmia before the SRS (odds ratio [OR] = 83.125; 95% CI [24.589-281.01], P < .001) and prior resection of OGM (OR = 3.919; 95% CI [1.713-8.970], P = .001). CONCLUSION: SRS is associated with durable local control of the majority of OGM patients with acceptable safety profile. SRS allows preservation or improvement of olfactory function in the majority of OGM patients.