The effect of radiosurgery during management of aggressive meningiomas

BACKGROUND: Aggressive (atypical or malignant) meningiomas are difficult tumors to manage. We review the local control and survival rates of patients with aggressive meningiomas after multi-modality therapy that included stereotactic radiosurgery (SRS). METHODS: Thirty patients had SRS for treatment of malignant (n = 12) or atypical (n = 18) meningiomas. There were 17 (57%) males and 13 (43%) females with an average age of 58 years. The mean number of prior surgical resections was two. The median imaging follow-up was 2.3 (0.1-11.4) years; median clinical follow-up was 3.8 (0.25-11.5) years. RESULTS: After SRS, the overall median time until progression of neurologic signs was 48.0 (+/-6.51) months. Median time to neurologic progression was significantly worse for patients treated late after recurrence versus early after craniotomy. Atypical meningiomas had 5- and 10-year overall actuarial survival rates of 59% (+/-13), while malignant meningiomas had 5- and 10-year overall actuarial survival rates of 59% (+/-16) and 0%. These curves were not significantly different from one another. Atypical meningiomas had a 5-year progression-free survival (PFS) of 83% (+/-7%), while malignant meningiomas had a 5-year PFS of 72% (+/-10) (p = 0.018). On multivariate analysis, early SRS and smaller tumor volumes were associated with better PFS, while younger age was associated with better survival. One patient had an adverse radiation effect after SRS. CONCLUSIONS: Stereotactic radiosurgery is an important adjuvant management strategy for residual tumors identified early after craniotomy and partial resection. Aggressive use of early boost radiosurgery following craniotomy and radiation therapy is recommended for patients with malignant meningiomas.     

Long-term outcomes of Gamma Knife surgery for cavernous sinus meningioma

OBJECT: The aim of this study was to evaluate long-term outcomes, including tumor control and neurological function, in patients with cavernous sinus meningiomas treated using Gamma Knife surgery (GKS). METHODS: One hundred fifteen patients with cavernous sinus meningiomas, excluding atypical or malignant meningiomas, were treated with GKS between 1991 and 2003. Forty-nine patients (43%) underwent GKS as the initial treatment. The mean tumor volume was 14 cm3, and the mean maximum and margin doses applied to the tumor were 27 and 13 Gy, respectively. The median follow-up period was 62 months. During the follow-up, 111 patients were able to be evaluated with neuroimaging. RESULTS: The actuarial 5- and 10-year progression-free survival rates were 87 and 73%, respectively. Similarly, the actuarial 5- and 10-year focal tumor control rates were 94 and 92%, respectively. Regarding functional outcomes, 43 patients (46%) experienced some degree of improvement, 40 (43%) remained stable, and 11 (12%) had worse preexisting or newly developed symptoms. Patients who underwent GKS as the initial treatment experienced significant improvement of their symptoms (p = 0.006). CONCLUSIONS: Gamma Knife surgery is a safe and effective treatment over the long term in selected patients with cavernous sinus meningiomas. Tumor progression is more likely to occur from the lesion margin outside the treatment volume. In small to medium-sized tumors, GKS is an excellent alternative to resection, preserving good neurological function. For relatively large-sized tumors, low-dose radiosurgery (< or = 12 Gy) is acceptable for the prevention of tumor progression.     

Stereotactic radiosurgery providing long-term tumor control of cavernous sinus meningiomas

OBJECT: To evaluate long-term outcomes of patients who have undergone stereotactic radiosurgery for cavernous sinus meningiomas, the authors retrospectively reviewed their 14-year experience with these cases. METHODS: One hundred seventy-six patients harbored meningiomas centered within the cavernous sinus. Seventeen patients were lost to follow-up review, leaving 159 analyzable patients, in whom 164 procedures were performed. Seventy-six patients (48%) underwent adjuvant radiosurgery after one or more attempts at surgical resection. Eighty-three patients (52%) underwent primary radiosurgery. Two patients (1%) had previously received fractionated external-beam radiation therapy. Four patients (2%) harbored histologically verified atypical or malignant meningiomas. Conformal multiple isocenter gamma knife surgery was performed. The median dose applied to the tumor margin was 13 Gy. Neurological status improved in 46 patients (29%), remained stable in 99 (62%), and eventually worsened in 14 (9%). Adverse effects of radiation occurred after 11 procedures (6.7%). Tumor volumes decreased in 54 patients (34%), remained stable in 96 (60%), and increased in nine (6%). The actuarial tumor control rate for patients with typical meningiomas was 93.1 +/- 3.3% at both 5 and 10 years. For the 83 patients who underwent radiosurgery as their sole treatment, the actuarial tumor control rate at 5 years was 96.9 +/- 3%. CONCLUSIONS: Stereotactic radiosurgery provided safe and effective management of cavernous sinus meningiomas. We believe it is the preferred management strategy for tumors of suitable volume (average tumor diameter < or = 3 cm or volume < or = 15 cm3).     

Linear accelerator-based stereotactic radiosurgery of intracranial meningiomas: results of the first 5 years of clinical practice

Meningiomas are mostly benign but some are atypical or malignant. Surgical resection is curative when complete removal of benign meningiomas is contemplated. Incompletely excised and recurrent tumors are frequently treated with fractionated radiation therapy or stereotactic radiosurgery. The purpose of this study is to evaluate the short-term radiological and functional outcomes of a single center using linear accelerator (Linac) stereotactic radiosurgery for the treatment of intracranial meningiomas. Twenty-nine patients (12 males and 17 females) with 30 meningiomas, in different brain locations (skull base and non-skull base meningiomas), were treated with Linac-based stereotactic radiosurgery. The mean tumor volume was 6.3 cm³, and the mean tumor marginal and maximum doses were 10.9 and 15 Gy, respectively. The median prescribed isodose line was 80%. The patients were followed-up for a minimum of 3 years. Regarding radiological outcome, nine (30%) meningiomas demonstrated evident volume reduction, 19 (63.3%) meningiomas remained unchanged, and two (6.7%) meningiomas increased in size after radiosurgery. The local tumor control rates for skull base meningiomas and non-skull base meningiomas after radiosurgery were 90.9% and 100%, respectively. Regarding functional outcomes, 64% of patients presenting with cranial neuropathies showed improvement of their cranial nerve functions and 29% of patients remained unchanged. One patient had temporary trigeminal neuropathy. Although radiosurgery for meningiomas is generally effective and quite safe in achieving high control rates with minimum morbidity over short- and intermediate-term periods of follow-up, tumor progression might occur in a delayed manner after initial apparent control for few years. We recommend continued follow-up for longer periods to better assess the long-term outcomes.     

Surgical resection and permanent brachytherapy for recurrent atypical and malignant meningioma

OBJECTIVE: Recurrent atypical and malignant meningiomas are difficult to treat successfully. Chemotherapy to date has been unsuccessful, and radiosurgery is limited to smaller tumors. Reoperation alone provides limited tumor control and limited prolonged survival. The addition of brachytherapy at the time of operation is an option. Here, we report the results of our series of patients with recurrent malignant meningioma treated with resection and brachytherapy with permanent low-dose (125)I. METHODS: The charts of patients in our database with recurrent atypical and malignant meningiomas treated by surgical resection and permanent (125)I brachytherapy at the University of California, San Francisco, between 1988 and 2002 were selected for this study. Calculations of disease-free survival and overall survival curves were made by the Kaplan-Meier actuarial method. Univariate analysis between Kaplan-Meier curves was based on the log-rank statistic, with a significance level set at a value of P 相似文献   

Radiosurgery for Atypical and Anaplastic Meningiomas: Histopathological Predictors of Local Tumor Control

Objectives: We investigated the radiosurgical outcomes of patients with nonbenign meningiomas retrospectively and sought to identify prognostic factors for local tumor control after radiosurgery with an emphasis on histopathology. Methods: Between 1998 and 2010, 35 patients with 49 atypical or anaplastic meningiomas were treated with radiosurgery. The mean tumor volume and marginal irradiation dose were 3.5 cm(3) (range 0.3-25.3) and 16 Gy (range 12-21), respectively. Results: The actuarial local tumor control rates for patients with atypical meningiomas at 1, 2 and 3 years after radiosurgery were 78, 53 and 36%, respectively, whereas those for anaplastic meningiomas were 35% at 1 year and 10% at 2 years. Multivariate analysis revealed that the mitotic count (≤8 per 10 high-power fields; HPF) and the MIB-1 proliferation marker labeling index (LI; ≤8%) were significant favorable prognostic factors for the radiosurgical outcomes of patients with nonbenign meningiomas (p = 0.014 and p = 0.012, respectively). Conclusions: Radiosurgery could be a treatment option for patients with atypical meningiomas, but more aggressive treatments are needed for those with anaplastic meningiomas. Histopathological factors such as mitotic count and MIB-1 LI are significant prognostic factors for the radiosurgical outcomes of patients with nonbenign meningiomas and should be considered before radiosurgery.     

Radiosurgery as primary management for meningiomas extending into the internal auditory canal

Stereotactic radiosurgery is increasingly utilized as primary management for patients with skull base meningiomas. This study reviews the results of stereotactic radiosurgery for patients with meningiomas extending into the internal auditory canal (IAC) to determine the risk of facial weakness or hearing loss. From 1990 to 2002, 16 patients had radiosurgery for meningiomas extending into the IAC. The median patient age was 63 years. Ten patients had symptoms of vestibulocochlear nerve dysfunction before radiosurgery. The median tumor volume was 5.1 cm3; the median tumor extension into the IAC was 7 mm (range, 3-12). The median tumor margin dose was 15 Gy. The median follow-up was 36 months. Ten meningiomas (63%) decreased in size, and 6 tumors were unchanged. No patient developed facial weakness. One patient (6%) had worsened facial sensation. Three of 14 patients (21%) with either normal hearing clinically (n = 5) or documented Gardner-Robertson class 1-2 before radiosurgery (n = 9) had decreased hearing after radiosurgery. The 1-, 2- and 5-year actuarial incidences of hearing preservation were 93, 84 and 42%, respectively. Three patients (19%) had improved hearing after radiosurgery. One patient with class 2 hearing improved to class 1; 2 patients with no speech discrimination before radiosurgery (class 5) improved to a class 3 status following the procedure. The risk of facial weakness or hearing loss is low after radiosurgery for patients with meningiomas extending into the IAC. Radiosurgery is an excellent alternative to surgical excision for meningiomas in this location, especially if a subtotal resection is likely or a hearing-sacrificing operation such as a translabyrinthine approach is contemplated.     

Stabilization of disease progression by hydroxyurea in patients with recurrent or unresectable meningioma

OBJECT: The management of certain meningiomas of the skull base and those involving the dural venous sinuses remains a challenge. In recent reports it has been suggested that hydroxyurea chemotherapy can cause regression of unresectable and recurrent meningiomas. The authors report their experience in using hydroxyurea for the treatment of patients with recurrent or unresectable meningiomas. METHODS: Hydroxyurea was administered at a dosage of approximately 20 mg/kg/day to 11 women and nine men (median age 59 years, range 31-75 years) with recurrent or unresectable intracranial meningiomas (12 basal, two parasagittal, and six multiple). In 16 patients the meningiomas were benign, in three they had atypical features, and in one the meningioma was malignant. All patients had measurable residual disease. Four patients with benign meningiomas had previously received radiotherapy (two were treated with conventional fractionated radiotherapy and two with stereotactic radiosurgery), three with atypical meningiomas received conventional fractionated radiotherapy, and the one with a malignant meningioma received conventional radiotherapy with additional stereotactic radiosurgery. Tumor enlargement was documented in all patients on neuroimages obtained before initiation of hydroxyurea therapy. All patients were evaluable for response to therapy. In 12 patients with benign meningiomas, the disease had stabilized on neuroimages obtained posttreatment (median duration of treatment 122 weeks, range 8-151 weeks), and two of these showed clinical improvement. One patient with a benign meningioma experienced a minor partial response that was noted after 39 weeks of treatment and was confirmed on neuroimaging and clinical evaluations. In three others with benign meningiomas, progression was confirmed on neuroimages obtained after 41, 55, and 66 weeks, respectively: the 1-year freedom from progression rate was 0.93 (standard error 0.07) in patients with benign meningiomas. In three patients with atypical meningiomas, the tumors had progressed on neuroimages obtained after 12, 19, and 45 weeks, respectively. In the patient with a malignant meningioma, progression was confirmed on neuroimages obtained at 24 weeks. Hydroxyurea has been reasonably well tolerated, although one patient discontinued therapy because of moderate myelosuppression. CONCLUSIONS: Although tumor regression appears uncommon, these results indicate that hydroxyurea may arrest progression of unresectable or recurrent benign meningiomas.     

Stereotactic radiation treatment for recurrent nonbenign meningiomas

OBJECT: The authors analyzed the results of stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) for the treatment of recurrent meningiomas that were described at initial resection as showing aggressive, atypical, or malignant features (nonbenign). METHODS: Twenty-five patients who underwent SRS and/or SRT for nonbenign meningiomas between December 1992 and August 2004 were included. Thirteen of these patients underwent treatment for multiple primary or recurrent lesions. In all, 52 tumors were treated. All histological sections were reviewed and reclassified according to World Health Organization (WHO) 2000 guidelines as benign (Grade I), atypical (Grade II), or anaplastic (Grade III) meningiomas. The median follow-up period was 42 months. Seventeen (68%) of the cases were reclassified as follows: WHO Grade I (five cases), Grade II (11 cases), and Grade III (one case). Malignant progression occurred in eight cases (32%) during the follow-up period; these cases were considered as a separate group. The 3-year progression-free survival (PFS) rates for the Grades I, II, and III, and malignant progression groups were 100, 83, 0, and 11%, respectively (p < 0.001). In the Grade II group, the 3-year PFS rates for patients treated with SRS and SRT were 100 and 33%, respectively (p = 0.1). After initial treatment, 22 new tumors required treatment using SRS or SRT; 17 (77%) of them occurred inside the original resection cavity. Symptomatic edema developed in one patient (4%). CONCLUSIONS: Stereotactic radiation treatment provided effective local control of "aggressive" Grade I and Grade II meningiomas, whereas Grade III lesions were associated with poor outcome. The outcome of cases in the malignant progression group was intermediate between that of the Grade II and Grade III groups, with the lesions showing a tendency toward malignancy.     

Classic, atypical, and anaplastic meningioma: three histopathological subtypes of clinical relevance.

This study correlates the histopathological classification of meningiomas with clinicopathological features of biological activity. A retrospective evaluation of 1799 surgical specimens of meningiomas from 1582 patients was made. The classic histopathological type, atypical meningiomas defined by increased cellularity and at least five mitotic figures in 10 high-power fields, anaplastic (malignant) meningiomas, and hemangiopericytic or papillary meningiomas were seen in 87.6%, 7.2%, 2.4%, and 2.8% of operations, respectively. The rates of recurrence in surgically treated patients with classic, atypical, anaplastic, and hemangiopericytic or papillary meningiomas were 6.96%, 34.6%, 72.7%, and 68.2%, respectively. The extent of surgery and the tumor size and site were studied in detail in 252 tumors of all histopathological types. Recurrences were rare in classic meningiomas after complete resection, whereas atypical and anaplastic tumors recurred after complete resection much more frequently. Classic meningiomas, hemangiopericytomas, and papillary meningiomas were smaller at surgery than atypical and malignant meningiomas. Atypical and malignant tumors were operated on more often in falcine and lateral convexity regions than were classic meningiomas. To support the authors' subjective categorization by a quantitative parameter related to proliferation, 112 meningiomas comprising all histopathological subtypes were investigated for staining of argyrophilic nucleolar organizer region proteins (Ag-NOR's). The Ag-NOR counts showed significant differences between classic, atypical, and anaplastic tumors but no significant differences between primary and recurrent tumors. Hemangiopericytomas and papillary meningiomas had lower Ag-NOR values than anaplastic meningiomas. A correlation of Ag-NOR numbers with the authors' histopathological scale of malignancy supports the introduction of atypical meningiomas with intermediate biological behavior on the classification scale between classic and anaplastic meningiomas. Overlapping of Ag-NOR numbers among all groups of malignancy may restrict the prognostic value of Ag-NOR counting in the individual case.     

Brain metastases treated with radiosurgery alone: an alternative to whole brain radiotherapy?

OBJECTIVE: Whole brain radiotherapy (WBRT) provides benefit for patients with brain metastases but may result in neurological toxicity for patients with extended survival times. Stereotactic radiosurgery in combination with WBRT has become an important approach, but the value of WBRT has been questioned. As an alternative to WBRT, we managed patients with stereotactic radiosurgery alone, evaluated patients' outcomes, and assessed prognostic factors for survival and tumor control. METHODS: One hundred seventy-two patients with brain metastases were managed with radiosurgery alone. One hundred twenty-one patients were evaluable with follow-up imaging after radiosurgery. The median patient age was 60.5 years (age range, 16-86 yr). The mean marginal tumor dose and volume were 18.5 Gy (range, 11-22 Gy) and 4.4 ml (range, 0.1-24.9 ml). Eighty percent of patients had solitary tumors. RESULTS: The overall median survival time was 8 months. The median survival time in patients with no evidence of primary tumor disease or stable disease was 13 and 11 months. The local tumor control rate was 87%. At 2 years, the rate of local control, remote brain control, and total intracranial control were 75, 41, and 27%, respectively. In multivariate analysis, advanced primary tumor status (P = 0.0003), older age (P = 0.008), lower Karnofsky Performance Scale score (P = 0.01), and malignant melanoma (P = 0.005) were significant for poorer survival. The median survival time was 28 months for patients younger than 60 years of age, with Karnofsky Performance Scale score of at least 90, and whose primary tumor status showed either no evidence of disease or stable disease. Tumor volume (P = 0.02) alone was significant for local tumor control, whereas no factor affected remote or intracranial tumor control. Eleven patients developed complications, six of which were persistent. Nineteen (16.5%) of 116 patients in whom the cause of death was obtained died as a result of causes related to brain metastasis. CONCLUSION: Brain metastases were controlled well with radiosurgery alone as initial therapy. We advocate that WBRT should not be part of the initial treatment protocol for selected patients with one or two tumors with good control of their primary cancer, better Karnofsky Performance Scale score, and younger age, all of which are predictors of longer survival.     

Long-term results after radiosurgery for benign intracranial tumors

BACKGROUND: Stereotactic radiosurgery is the principal therapeutic alternative to resecting benign intracranial tumors. The goals of radiosurgery are the long-term prevention of tumor growth, the maintenance of patient function, and the prevention of new neurological deficits or adverse radiation effects. Evaluation of long-term outcomes more than 10 years after radiosurgery is needed. METHODS: We evaluated 285 consecutive patients who underwent radiosurgery for benign intracranial tumors between 1987 and 1992. Serial imaging studies were obtained, and clinical evaluations were performed. Our series included 157 patients with vestibular schwannomas, 85 patients with meningiomas, 28 patients with pituitary adenomas, 10 patients with other cranial nerve schwannomas, and 5 patients with craniopharyngiomas. Prior surgical resection had been performed in 44% of these patients, and prior radiotherapy had been administered in 5%. The median follow-up period was 10 years. RESULTS: Overall, 95% of the 285 patients in this series had imaging-defined local tumor control (63% had tumor regression, and 32% had no further tumor growth). The actuarial tumor control rate at 15 years was 93.7%. In 5% of the patients, delayed tumor growth was identified. Resection was performed after radiosurgery in 13 patients (5%). No patient developed a radiation-induced tumor. Eighty-one percent of the patients were still alive at the time of this analysis. Normal facial nerve function was maintained in 95% of patients who had normal function before undergoing treatment for acoustic neuromas. CONCLUSION: Stereotactic radiosurgery provided high rates of tumor growth control, often with tumor regression, and low morbidity rates in patients with benign intracranial tumors when evaluated over the long term. This study supports radiosurgery as a reliable alternative to surgical resection for selected patients with benign intracranial tumors.     

Radiosurgical treatment of cavernous sinus meningiomas: experience with 122 treated patients

OBJECTIVE: To evaluate the efficacy of gamma knife (GK) radiosurgery, in terms of neurological improvement and tumor growth control (TGC), for a large series of patients with cavernous sinus meningiomas. METHODS: Between February 1993 and January 2002, 156 patients with cavernous sinus meningiomas (35 male and 121 female patients; mean age, 56.1 yr) were treated with GK radiosurgery in our department. GK radiosurgery was used as a first-choice treatment for 75 of 156 patients and as postoperative adjuvant therapy for 81 of 156 patients (all with Grade I meningiomas). Eligibility criteria for radiosurgery were as follows: symptomatic meningiomas and/or documented tumor progression on magnetic resonance imaging scans, conditions of high operative risk, patient refusal of microsurgery or reoperation, tumor volume of <20 cm(3), and location no less than 2 mm from the optic pathways. RESULTS: Follow-up data for at least 12 months were available for 122 patients (median follow-up period, 48.9 mo). Clinical conditions were improved or stable for 118 of 122 patients (97%). Neurological recovery was observed for 78.5% of patients treated with GK radiosurgery alone and for 60.5% of patients treated with adjuvant therapy (P < 0.05). Adequate TGC was documented for 119 of 122 tumors (97.5%), with shrinkage/disappearance in 75 of 122 cases (61.5%) and no variation in volume in 44 of 122 cases (36%); the overall actuarial progression-free survival rate at 5 years was 96.5%. Tumor size regression was observed for 80% of patients with follow-up periods of more than 30 months, compared with 43.5% of patients with follow-up periods of less than 30 months (P < 0.0002). Radiosurgical sequelae were transient in 4 of 122 cases (3.0%) and permanent in 1 case (1%). CONCLUSION: For the follow-up periods in our series (median, >4 yr), GK radiosurgery seems to be both safe (permanent morbidity rate, 1%) and effective (97% neurological improvement/stability, 97.5% overall TGC, and 96.5% actuarial TGC at 5 yr). GK radiosurgery might be considered a first-choice treatment for selected patients with cavernous sinus meningiomas.     

The surgical treatment strategy and results of parasellar meningiomas in the era of radiosurgery

We evaluated the surgical treatment results of parasellar meningiomas in the era of radiosurgery. We treated 24 patients of parasellar meningiomas surgically. The median age was 60 yrs (ranging from 29 to 82 yrs). The most common tumor location was the sphenoid ridge in 12 patients and the tuberculum sellae in 7 patients. The pterional approach using fronto-temporal craniotomy was performed for all patients. The residual or recurrent tumors were treated by gamma knife radiosurgery (GKS). We are able to follow up these cases for a median of 3.8 yrs (ranging from 1 to 8 yrs) after the operations. The radicality of tumor resection was Simpson grade II in 13 patients (54%), grade III in 3 patients (13%) and grade IV in 7 patients (33%). Clinical improvement was achieved in 81% of the patients. Of the patients who had visual disturbance preoperatively, 8 patients (73%) showed improvement, but 3 patients suffered deterioration postoperatively. None of the patients died. One patient suffered transient memory disturbance and one patient suffered mild facial numbness postoperatively. Boost radiosurgery for the residual tumors was performed for six patients and tumor growth control was able to be achieved in all patients, with a median of 3.1 years follow-up period (ranging from 0.5 to 6 yrs). Five patients with tumor regrowth or recurrence were treated by GKS. We recommend fronto-temporal craniotomy with nonradical resection for parasellar meningiomas and radiosurgery for residual and recurrent tumors. This strategy will achieve good functional outcome with long-term tumor growth control.     

Adjuvant stereotactic radiosurgery for anaplastic ependymoma

OBJECT: The purpose of this retrospective study is to evaluate the role of stereotactic radiosurgery using the Gamma Knife as an adjuvant to other modalities used in the treatment of malignant ependymomas of both children and adults and to assess its efficacy in terms of tumor control and overall survival. METHOD: Between 1987 and 1998, 22 patients in the age range of 1.5-65 years (mean age 22. 3) with progressive anaplastic ependymoma were treated by stereotactic radiosurgery using the 201 source Co-60 Leksell Gamma Knife at the University of Pittsburgh. The irradiated tumor volume varied from 0.84 to 36.8 cm(3) (mean 13.7). The median dose delivered to the tumor margin was 16.1 Gy (range 10-20), and the mean maximal dose was 32.2 Gy (range 20-40). The disease-free survival, the tumor control rate and the overall survival were recorded to evaluate the efficacy of radiosurgery. The median follow-up from radiosurgery was 21 months (range 4-84). RESULTS: Median survival after radiosurgery was 2.2 years (46.6 +/- 12.1% 5-year actuarial). Median survival from the initial diagnosis was 10. 1 years (50.3 +/- 12.5% at 5 years, 37.7 +/- 14.4% at 10 years). Reduction or stabilization of the treated tumor was seen in 16 out of 22 (68%) patients. Forty-one percent of the patients eventually developed delayed distant cerebral recurrence outside the treated volume. The 5-year actuarial rates for local control and cranial control at any location were 62.3 +/- 13.6% and 32.4 +/- 10.8%, respectively. No complication occurred as a side effect of radiosurgery. CONCLUSION: For patients with locally recurrent or progressive anaplastic ependymomas, Gamma Knife stereotactic radiosurgery proved to be safe and effective as a salvage adjuvant therapy to achieve local tumor control and improve survival.     

Long-term outcomes after meningioma radiosurgery: physician and patient perspectives.

OBJECT: Stereotactic radiosurgery is a primary or adjuvant management approach used to treat patients with intracranial meningiomas. The goal of radiosurgery is long-term prevention of tumor growth, maintenance of the patient's neurological function, and prevention of new neurological deficits. The object of this study is to report longer-term patient outcomes. METHODS: The authors evaluated 99 consecutive patients who underwent radiosurgery for meningioma between 1987 and 1992. Evaluation was performed using serial imaging tests, clinical evaluations, and a patient survey that was administered between 5 and 10 years after radiosurgery. Four patients underwent two radiosurgery procedures for separate meningiomas. The average tumor margin dose was 16 Gy and the median tumor volume was 4.7 ml (range 0.24-24 ml). Fifty-seven patients (57%) had undergone prior resection, of which 12 procedures were considered "total." Five patients received fractionated radiation therapy before radiosurgery. Eighty-nine patients (89%) had skull base tumors. The clinical tumor control rate (no resection required) was 93%. Sixty-one (63%) of 97 tumors became smaller, 31 (32%) remained unchanged in size, and five (5%) were enlarged. Resection was performed in seven patients (7%), six of whom had undergone prior resection. New neurological deficits developed in five patients (5%) 3 to 31 months after radiosurgery. Twenty-seven (42%) of 65 responding patients were employed at the time of radiosurgery and 20 (74%) of these remained so. Radiosurgery was believed to have been "successful" by 67 of 70 patients who completed an outcomes questionnaire 5 to 10 years later. At least one complication was described by nine patients (14%) and in four patients the complications resolved. CONCLUSIONS: Five to 10 years after radiosurgery, 96% of surveyed patients believed that radiosurgery provided a satisfactory outcome for their meningioma. Overall, 93% of patients required no other tumor surgery. Incidences of morbidity in this early experience were usually transitory and relatively mild. Radiosurgery provided long-term tumor control associated with high rates of neurological function preservation and patient satisfaction.     

Linac Radiosurgery for Skull Base Meningiomas

Summary  Introduction. Skull base meningiomas present a difficult surgical challenge because of the high potential morbidity of radical surgical extirpation and their low potential for incapacitating symptomatology. The focal character of meningiomas makes stereotactic radiosurgery an attractive adjuvant treatment modality to resection. The purpose of this study was to evaluate the local control rates and complications in 56 patients with base of skull meningiomas undergoing radiosurgery.  Methods. Patients underwent radiosurgery using the dedicated stereotactic linear accelerator at the Brigham and Women's Hospital. Minimal peripheral doses of radiosurgery ranged from 12 to 18.5 Gy (mean 15 Gy). Doses were designed to conform to the frequently irregular tumor volumes using the X-Knife treatment planning system. Multiple isocenters were used when required to increase conformality of dose. For 36 patients (64%), radiosurgery was used as an adjunct to surgery; for 20 patients (36%) it was the primary treatment.  Results. Median followup was five years. Nineteen patients (34%) were improved clinically at follow-up; 32 (57%) were unchanged; and 5 patients (9%) developed new or worsened neurologic deficits. Serial imaging studies after radiosurgery showed a reduction in tumor volume in 23 patients (41%); 30 (54%) showed stable disease; 3 patients (5%) had tumors which increased in size (2 being outside the radiosurgery treatment site). The actuarial freedom from progression rate (defined as further tumor growth) was thus 95%, with a median imaging follow-up of 26 months (range, 6–66 months).  Although further follow-up is necessary, the results of this series clearly demonstrate that these lesions are feasible for treatment by modern radiosurgical techniques. Linac radiosurgery can stabilize skull base meningiomas, with decreased or unchanged tumor volumes on radiologic follow-up in approximately 95% of patients. Radiosurgery is a low-morbidity, effective technique as adjunct and sometimes primary treatment of small to moderate-sized meningiomas of the skull base.     

Association between absence of epidermal growth factor receptor immunoreactivity and poor prognosis in patients with atypical meningioma

OBJECT: The clinical behavior of meningiomas is variable. Because multiple growth factor receptors have been identified in these tumors, the authors sought to assess the capacity of the expression patterns of a subset of these receptors to stratify meningioma cases. METHODS: Eighty-four meningiomas were analyzed, including 36 benign, 29 atypical, and 19 malignant lesions. Immunohistochemical staining was performed for epidermal growth factor receptor (EGFR), platelet-derived growth factor receptor (PDGFR)-beta, basic fibroblast growth factor receptor (BFGFR), and MIB-1. Survival analyses were performed using follow-up data obtained in patients with newly diagnosed tumors. Immunoreactivity for EGFR was observed in 47% of benign, 48% of atypical, and 42% of malignant tumors. Staining for BFGFR was identified in 89% of benign, 97% of atypical, and 95% of malignant lesions. Immunostaining for PDGFR-beta was evident in all the lesions assessed. Mean MIB-I indices for benign, atypical, and malignant cases were 3.6 (range 0.5-15.3), 8.2 (range 1.5-23.1) and 18.3 (range 1.0-55.8), respectively. Overall mean follow-up duration was 9.0 years (range 5.1-18.8 years). Lack of EGFR immunoreactivity was identified as a strong predictor of shorter overall survival in patients with atypical meningioma (p = 0.003, log-rank test). This association was not evident in cases of benign or malignant meningiomas. CONCLUSIONS: There is a significant association between EGFR immunoreactivity and prolonged survival in patients with atypical meningioma. Given the variable behavior of atypical meningiomas, EGFR assessment could improve existing strategies for patient stratification and treatment.     

MIB-1 staining index of pediatric meningiomas

OBJECTIVE: For adult meningiomas, the staining index (SI) for the anti-Ki-67 monoclonal antibody MIB-1 is well correlated with histological atypia and tumor recurrence. MIB-1 SIs for meningiomas in the pediatric population have not been previously reported. Meningiomas tend to be more histologically aggressive and to recur more frequently in children, compared with adults. The objectives of this study were to determine whether MIB-1 SIs are correlated with pathological atypia and recurrence among pediatric meningiomas and to compare the MIB-1 SIs of pediatric meningiomas with those of adult meningiomas. METHODS: MIB-1 SIs were assessed on paraffin-embedded sections of 14 pediatric meningiomas (patient age, 2-17 yr), 5 of which contained atypical or malignant features. For comparison with benign pediatric meningiomas, MIB-1 SIs were also assessed on paraffin-embedded sections of 14 adult meningiomas (patient age, 38-90 yr), none of which displayed atypical or malignant features or recurred within a 5-month median follow-up period. RESULTS: MIB-1 SIs of pediatric meningiomas ranged from 1.2 to 31.6% (median, 9.1%). Significant differences were observed between the MIB-1 SIs for tumors with atypical or malignant features (median, 12.3%; range, 7.0-31.6%) and those for tumors without atypia (median, 7.0%; range, 1.2-12.6%; P = 0.045). There were six recurrences after gross total resection, during a 36.5-month median follow-up period. All five of the tumors with pathological atypia recurred; one tumor without atypia recurred. Significant differences were observed between MIB-1 SIs for nonrecurrent tumors (median, 6.6%; range, 1.2-12.2%) and those for recurrent tumors (median, 12.5%; range, 7.0-31.6%; P = 0.012). The median MIB-1 SI for adult control specimens was 8.8% (range, 1.2-19.3%), which did not differ significantly from that for pediatric meningiomas without atypia (P = 0.68). CONCLUSION: For this cohort of pediatric meningiomas, pathological atypia and the tendency to recur were correlated with elevated MIB-1 SIs. The median MIB-1 SI for pediatric meningiomas without histological atypia did not differ significantly from that for adult meningiomas without atypia, suggesting that the more aggressive clinical features of meningiomas in children may be attributable to factors other than the rate of cellular proliferation.