Stereotactic radiotherapy of benign meningioma in the elderly: clinical outcome and toxicity in 121 patients.

BACKGROUND AND PURPOSE: To investigate the outcome of definitive stereotactic-based radiotherapy in elderly patients (≥70 years of age) with benign intracranial meningiomas. MATERIALS AND METHODS: 121 patients were treated with either fractionated stereotactic radiotherapy (FRTS; n=74), hypofractionated FSRT (hFSRT; n=35) or stereotactic radiosurgery (SRS; n=12), depending on tumor size and location. Local control (LC), overall survival (OS), cause-specific survival (CSS), symptomatology and acute and late toxicity were assessed. The prognostic value of factors such as age, sex, tumor location, Karnofsky performance scale, target volume and radiotherapy schedule was examined. RESULTS: The median follow-up was 40 months (range, 12-124 months). LC, OS and CSS at 3 years were 98.3%, 92% and 99% and at 5 years they accounted 94.7%, 79% and 94.3%, respectively. We failed to identify any significant prognostic factor for outcome. Only Grade I-II toxicity was observed, whereas no new neurologic deficits or treatment-related mortality were encountered. CONCLUSION: This is the first study to assess the outcome following radiotherapy in elderly patients with intracranial meningiomas. The high local control, the low toxicity and the lack of treatment-associated mortality make stereotactic radiotherapy an attractive option in an age population where neurosurgery is often correlated with some mortality.

Stereotactic radiation therapy for benign meningioma: long-term outcome in 318 patients.

PURPOSE: To investigate the long-term outcome of stereotactic-based radiation therapy in a large cohort of patients with benign intracranial meningiomas. METHODS AND MATERIALS: Between 1997 and 2010, 318 patients with histologically confirmed (44.7%; previous surgery) or imaging-defined (55.3%) benign meningiomas were treated with either fractionated stereotactic radiation therapy (79.6%), hypofractionated stereotactic radiation therapy (15.4%), or stereotactic radiosurgery (5.0%), depending on tumor size and location. Local control (LC), overall survival (OS), cause-specific survival (CSS), prognostic factors, and toxicity were analyzed. RESULTS: The median follow-up was 50 months (range, 12-167 months). Local control, OS, and CSS at 5 years were 92.9%, 88.7%, and 97.2%, and at 10 years they were 87.5%, 74.1%, and 97.2%, respectively. In the multivariate analysis, tumor location (P=.029) and age >66 years (P=.031) were predictors of LC and OS, respectively. Worsening of pre-existing neurologic symptoms immediately after radiation therapy occurred in up to 2%. Clinically significant acute toxicity (grade 3°) occurred in 3%. Only grade 1-2 late toxicity was observed in 12%, whereas no new neurologic deficits or treatment-related mortality were encountered. CONCLUSIONS: Patients with benign meningiomas predominantly treated with standard fractionated stereotactic radiation therapy with narrow margins enjoy excellent LC and CSS, with minimal long-term morbidity.

Stereotactic radiosurgery of cerebral arteriovenous malformations: long-term follow-up in 164 patients of a single institution.

This retrospective study aimed to investigate long-term outcome in patients with arteriovenous malformations (AVM) treated with stereotactic radiosurgery (SRS). Between 1998 and 2008, 164 patients with AVM received SRS. Median age was 36 years (range 7-69 years). Before SRS, 39 % of the patients experienced haemorrhage and 27 % suffered from epileptic seizures, whereas 43 % received previously embolization, 7.9 % neurosurgery and 1.8 % proton radiotherapy. Primary SRS was applied in 51.2 % of the patients. Median single dose was 19 Gy (80 % isodose; range 18-20 Gy) and median target volume was 4 cc (range 0.1-24.4). Median follow-up was 93 months (range 12-140). Complete obliteration (CO) was observed in 100 (61 %) patients at a median time of 29 months (range 6.1-88.5). The 3 and 5-year CO rates were 61 and 88 %, respectively. In multivariate analysis, radiation dose ≥ 19 Gy (p = 0.044) and target volume <4 cc (p = 0.015) were associated with significantly higher rates of CO. Intracranial haemorrhage was seen in nine patients (5.5 %) after SRS, whereas three patients (1.8 %) died as a consequence of bleeding. The annual bleeding risk was 1.3 % after 1 year and 1.3 % after 2 years, respectively. In multivariate analysis, only target volume >4 cm(3) (p = 0.031) and Spetzler-Martin grade III-V (p = 0.046) retained significance for increased risk of intracranial bleeding. After SRS an improvement in epileptic episodes, headaches and motor-sensory deficits was found in 8.5, 14 and 15 % of patients, respectively. Our long-term follow-up data show that SRS is an effective treatment option in AVM with low toxicity and bleeding risk, depending on AVM size and Spetzler-Martin grade. An improvement of neurologic symptoms is achievable.

Quality of life after stereotactic radiotherapy for meningioma: a prospective non-randomized study.

Stereotactic radiotherapy (SRT) is well-established in the treatment of meningiomas offering high local control with low toxicity. However, the impact of SRT on quality of life (QoL) of patients remains largely unknown. This work aimed to prospectively evaluate QoL (longitudinal analysis) during and after SRT of meningiomas. We performed a single center, one-armed, prospective non-randomized study to assess QoL before and at the end of SRT (median fraction dose: 1.8 Gy; median cumulative dose: 54.0 Gy) and furthermore biannually until 24 months after SRT with the "medical outcome study short form 36". This questionnaire evaluates 8 health parameters summarized in "physical component scale" (PCS) and "mental component scale" (MCS). Between 2005 and 2007, 67 patients were enrolled and treated with SRT. 42/52 patients underwent previous operations and 10/52 primary SRT. Complete follow-up data were available from 44 patients. Compared to the german normal population (GNP) a general decrease in the mean values of all parameters was observed. After SRT mean values still declined and 12 months after SRT all parameters normalized towards their initial values. The cohort (previous operations) had better values for MCS (p = 0.004). The cohort (primary SRT) had worse values for PCS that increased asymptotically 6 months after SRT to values of cohort (previous operations) (p = 0.054). Gender, age and tumor related symptoms did not affect QoL according to MCS and PCS (p > 0.05). Local control was 98 %. Treatment was well tolerated and no severe side effects were observed. Patients with meningiomas have an impaired QoL compared to GNP. The QoL assessment after SRT revealed three phases: "depressive phase", "recovery phase" and "normalization phase". Patients treated with primary SRT developed a stable increase of the mean values for PCS. Gender, age, applied dose, symptomatology did not affect QoL.

Stereotactic radiosurgery and fractionated stereotactic radiotherapy: comparison of efficacy and toxicity in 260 patients with brain metastases.

We retrospectively evaluated and compared the efficacy and the toxicity profile of stereotactic radiosurgery (SRS) and fractionated stereotactic radiotherapy (FSRT) for the treatment of patients with brain metastases (BM). Between 2000 and 2009, 260 patients with 1-3 BM were treated using either SRS (median dose 20 Gy; n = 138) or two different FSRT dose concepts: 7 × 5 Gy (n = 61) or 10 × 4 Gy (n = 61). The median survival for SRS, 7 × 5 Gy and 10 × 4 Gy was 8, 7 and 10 months (p = 0.575), respectively, and the overall survival (OS) was 9 months. Follow-up imaging data were available in 214 of the 260 patients. The 1-year local progression-free survival (LPFS) was 73, 75 and 71 %, respectively (p = 0.191). After a mean follow-up of 28 months (range: 2.1-77 months), the rate of complete remission, partial remission, stable disease and progressive disease were 29, 40, 21 and 10 %, respectively. On multivariate analysis, RPA class I was associated with better OS and regional progression-free survival (both p < 0.001). SRS was associated with a higher toxicity rate (grade I-III) compared to the 7 × 5 Gy and 10 × 4 Gy groups (14 vs. 6 vs. 2 %, respectively; p = 0.01). Although FSRT was used for large lesions and/or lesions near critical structures, the LPFS was comparable to SRS. Importantly, FSRT presented low toxicity and appears to be an effective and safe treatment for BM not amenable to SRS. The 10 × 4 Gy fractionation scheme warrants further investigation due to its efficacy and safe toxicity profile.

Brain metastases in breast cancer: analysis of the role of HER2 status and treatment in the outcome of 94 patients.

AIMS AND BACKGROUND: We investigated the impact of human epidermal growth factor receptor 2 (HER2) and prognostic factors in the outcome of patients with breast cancer that developed brain metastases. METHODS: . The data from 94 patients who received multidisciplinary therapy from 2001 to 2007 were retrospectively reviewed. Patients were assigned according to their HER2 status, and overall survival and time to brain metastases recurrence/progression were evaluated. The prognostic value of age, presence of extracerebral metastases, recursive partitioning analysis class, hormone therapy, systemic therapy and trastuzumab was assessed. RESULTS: The median overall survival and time to brain disease progression were 7.1 and 6.5 months, respectively. HER2 positivity (P = 0.006), treatment with trastuzumab (P = 0.025), chemotherapy (P = 0.011) and recursive partitioning analysis class I-II (P <0.001) were associated with prolonged survival on univariate analysis. On multivariate analysis, only recursive partitioning analysis class I-II (P <0.001) and triple-negative disease (P = 0.04) remained significant for overall survival, whereas time to brain metastases progression was only associated with recursive partitioning analysis class I-II (P = 0.001). The time from the diagnosis of primary disease to brain metastasis was slightly shorter in the HER2+ patients than in HER2- patients (36 vs 39 months). Intensified local treatment of brain metastasis incorporating whole-brain radiotherapy and/or radiosurgery and neurosurgery did not affect survival. Patients with triple-negative disease presented a significantly lower survival than the rest of the cohort (4 vs 8 months; P = 0.012). CONCLUSIONS: Recursive partitioning analysis class I-II was found to be the strongest independent predictive factor. Treatment with trastuzumab in HER2+ patients appeared to improve overall survival, probably due to the better control of systemic metastatic disease, but did not maintain significance in multivariate analysis. The dismal prognosis of patients with triple-negative breast cancer highlights the need to develop novel therapies to improve the poor survival.

Multidisciplinary treatment of brain metastases derived from colorectal cancer incorporating stereotactic radiosurgery: analysis of 78 patients.

BACKGROUND: We investigated the role of radiotherapy, including whole brain radiotherapy and stereotactic radiosurgery (SRS), and prognostic factors in patients with colorectal cancer (CRC) who developed brain metastases. PATIENTS AND METHODS: The data of 78 patients who received multidisciplinary treatment from 1996 to 2007 were reviewed. Overall survival (OS), intracerebral control (ICC), and local control (LC) were retrospectively analyzed. Six potential prognostic factors were evaluated: age, gender, number of brain metastases, extracerebral metastases, recursive partitioning analysis (RPA) class, and interval from tumor diagnosis to radiotherapy. RESULTS: The median OS and ICC for the entire cohort were 8 and 6 months, respectively. Surgical resection-incorporating treatment resulted in significant improvement in OS (P = .036). On multivariate analysis, OS and ICC were significantly correlated with lack of extracerebral metastases (P = .024 and P = .041, respectively), lower number of lesions (P < .001 and P = .007, respectively) and interval from primary CRC diagnosis (P < .001 and .005, respectively) whereas RPA class I-II demonstrated significance only for OS (P = .045). SRS-incorporating therapy revealed a 1-year LC probability of 85%. No association between LC and any of the potential prognostic factors was observed. CONCLUSION: Our data indicate that surgery can prolong survival in CRC patients with brain metastases. SRS-incorporating treatment provides excellent LC rates and should be considered for patients with 1-3 lesions. The strong association between survival and the prognostic factors identified in this study highlights a patient subset that may potentially benefit from new, more aggressive therapies.

A comparison of radiotherapy with radiotherapy plus surgery for brain metastases from urinary bladder cancer: analysis of 62 patients.

PURPOSE: To evaluate the role of radiotherapy (RT) and prognostic factors in 62 patients with brain metastases from transitional cell carcinoma (TCC) of the urinary bladder. PATIENTS AND METHODS: 62 patients received either RT (n = 49), including whole-brain radiotherapy (WBRT) and/or stereotactic radiosurgery (SRS), or surgery (OP) combined with WBRT (n = 13). Overall survival (OS), intracerebral control (ICC) and local control (LC) were retrospectively analyzed. Six potential prognostic factors were assessed: age, gender, number of brain metastases, extracerebral metastases, recursive partitioning analysis (RPA) class, and interval from tumor diagnosis to RT. RESULTS: Median OS and ICC for the entire cohort were 9 and 7 months. No significant difference between RT and OP + RT was found for OS (p = 0.696) and ICC (p = 0.996). On multivariate analysis, improved OS was associated with lack of extracerebral metastases (p < 0.001) and RPA class (p < 0.001), and ICC with the latter (p < 0.001). SRS-incorporating RT resulted in 1-, 2-, and 3-year LC probability of 78%, 66%, and 51%. No association between LC and any of the potential prognostic factors was observed. The results of the subgroup RPA class analyses were similar to the entire cohort. CONCLUSION: Patient outcome for the RT-alone arm was not significantly different from OP + RT. SRS-incorporating treatment offers excellent LC rates. RPA class and the presence of extracerebral metastases demonstrated a significant prognostic role for survival. The latter should be used as stratification factors in randomized trials and can help define the cohort of patients that may benefit from more aggressive therapies.

Atlas-based semiautomatic target volume definition (CTV) for head-and-neck tumors.

PURPOSE: To develop a new semiautomatic method to improve target delineation in head-and-neck cancer. METHODS AND MATERIALS: We implemented an atlas-based software program using fourteen anatomic landmarks as well as the most superior and inferior computerd tomography slices for automatic target delineation, using an advanced laryngeal carcinoma as an example. Registration was made by an affine transformation. Evaluation was performed with manually drawn contours for comparison. Three physicians sampled and further applied a target volume atlas to ten other computer tomography data sets. In addition, a rapid three-dimensional (3D) correction program was developed. RESULTS: The mean time to the first semiautomatic target delineation proposal was 2.7 minutes. Manual contouring required 20.2 minutes per target, whereas semiautomatic target volume definition with the rapid 3D correction was completed in only 9.7 minutes. The net calculation time for image registration of the target volume atlas was negligible (approximately 0.6 seconds). Our method depicted a sufficient adaptation of the target volume atlas on the new data sets, with a mean similarity index of 77.2%. The similarity index increased up to 85% after 3D correction performed by the physicians. CONCLUSIONS: We have developed a new, feasible method for semiautomatic contouring that saves a significant amount (51.8%) of target delineation time for head-and-neck cancer patients. This approach uses a target volume atlas and a landmark model. The software was evaluated by means of laryngeal cancer but has important implications for various tumor types whereby target volumes remain constant in form and do not move with respiration.

Radiotherapy for brain metastases from renal cell cancer: should whole-brain radiotherapy be added to stereotactic radiosurgery?: analysis of 88 patients.

PURPOSE: To evaluate the role of stereotactic radiosurgery (SRS) and whole-brain radiotherapy (WBRT) for the treatment of brain metastases in patients with renal cell cancer (RCC). PATIENTS AND METHODS: 88 patients were treated with either SRS (n = 51) or SRS + WBRT (n = 17) for one to three lesions, or with WBRT (n = 20) for more than three brain metastases. Overall survival (OS), intracerebral control (IC) and local control (LC) were retrospectively analyzed. Six potential prognostic factors were assessed: age, gender, number of brain metastases, extracerebral metastases, recursive partitioning analysis (RPA) class, and interval from tumor diagnosis to irradiation. RESULTS: The median times for OS, IC, and LC from the time of diagnosis were 11, 9, and 10 months. The median OS times for SRS, SRS + WBRT, and WBRT were 12, 16, and 2 months. Addition of WBRT to the SRS improved IC (p = 0.032) but not OS (p = 0.703). On multivariate analyses, improved OS was associated with the absence of extracerebral metastases (p < 0.001) and RPA class (p = 0.04), and IC with treatment (p = 0.019). SRS provided a 1-year, 2-year, and 3-year LC probability of 81%, 78%, and 55%, respectively. No association between LC and any of the potential prognostic factors was observed. The results of the subgroup analyses, regarding treatment modality, were similar to the entire cohort, particularly for RPA class I patients. CONCLUSION: Addition of WBRT to SRS offers better IC and should be considered for RCC patients with one to three brain metastases, especially in RPA class I group. SRS offers excellent LC rates, while WBRT should be reserved for patients with multiple metastases and poor prognosis.

Comparison of stereotactic radiosurgery and fractionated stereotactic radiotherapy of acoustic neurinomas according to 3-D tumor volume shrinkage and quality of life.

BACKGROUND AND PURPOSE: Stereotactic radiosurgery (SRS) and also fractionated stereotactic radiotherapy (SRT) offer high local control (LC) rates (> 90%). This study aimed to evaluate three-dimensional (3-D) tumor volume (TV) shrinkage and to assess quality of life (QoL) after SRS/SRT. PATIENTS AND METHODS: From 1999 to 2005, 35/74 patients were treated with SRS, and 39/74 with SRT. Median age was 60 years. Treatment was delivered by a linear accelerator. Median single dose was 13 Gy (SRS) or 54 Gy (SRT). Patients were followed up > or = 12 months after SRS/SRT. LC and toxicity were evaluated by clinical examinations and magnetic resonance imaging. 3-D TV shrinkage was evaluated with the planning system. QoL was assessed using the questionnaire Short Form-36. RESULTS: Median follow-up was 50/36 months (SRS/SRT). Actuarial 5-year freedom from progression/overall survival was 88.1%/100% (SRS), and 87.5%/87.2% (SRT). TV shrinkage was 15.1%/40.7% (SRS/SRT; p = 0.01). Single dose (< 13 Gy) was the only determinant factor for TV shrinkage after SRS (p = 0.001). Age, gender, initial TV, and previous operations did not affect TV shrinkage. Acute or late toxicity (> or = grade 3) was never seen. Concerning QoL, no significant differences were observed after SRS/SRT. Previous operations and gender did not affect QoL (p > 0.05). Compared with the German normal population, patients had worse values for all domains except for mental health. CONCLUSION: TV shrinkage was significantly higher after SRT than after SRS. Main symptoms were not affected by SRS/SRT. Retrospectively, QoL was neither affected by SRS nor by SRT.

Hypofractionated stereotactic reirradiation of recurrent glioblastomas : a beneficial treatment option after high-dose radiotherapy?

BACKGROUND AND PURPOSE: Recurrent malignant gliomas have a very poor prognosis. This trial aimed to evaluate the benefits of reirradiation in case of recurrent glioblastoma multiforme (GBM) using hypofractionated stereotactic radiotherapy (hFSRT) after primary high-dose percutaneous irradiation. PATIENTS AND METHODS: Between 1998 and 2008, 53 patients with recurrent GBM were treated by hFSRT based on CT and MR imaging. At the time of recurrence, a median total dose of 30 Gy (20-60 Gy) was delivered in median fractions of 3 Gy/day (2-5Gy). RESULTS: The reirradiation was well tolerated (no acute or late toxicity > grade 2), despite the relatively large median tumor volume (35.01 ml). Karnofsky Performance Score was the strongest predictor for survival after reirradiation (p = 0.0159). Tumor volume (p = 0.4690), patient age (p = 0.4301), second operation (p = 0.6930), and chemotherapy (p = 0.1466) at the time of reirradiation did not affect survival. After hFSRT, the median survival was 9 months, and the 1-year progression-free survival (PFS) amounted to 22%.The median overall survival from initial diagnosis was 27 months. 1-year survival from first diagnosis was 83%, 2-year survival 45%. The median time to progression from the end of initial irradiation to recurrence was 12 months. 1-year PFS before reirradiation was 40%. CONCLUSION: hFSRT as a secondary treatment of recurrent GBM is a feasible and effective treatment option. Only minor side effects were observed with prolonged life expectancy of 9 months.

Stereotactic radiotherapy for the treatment of nonacoustic schwannomas.

OBJECTIVE: Nonacoustic schwannomas are rare tumors in contrast to the most common neuromas of Cranial Nerve VIII. The current treatment of choice in these cases is microsurgical resection, but the risk of postoperative complications is high, especially in cavernous sinus-invading tumors. In many of these cases, it is not possible to achieve complete tumor removal, resulting in the probability of recurrences. For those patients, radiosurgery (RS) or stereotactic radiotherapy (SRT) can offer an alternate treatment. METHODS: Within a 5-year period (2000-2005), 19 intracranial nonacoustic neuromas were treated with SRT-13 trigeminal neuromas, five neuromas of the lower cranial nerves (jugular foramen), and one located in the orbital region. Of these cases, there were nine women and 10 men who were, on average, 54 years of age (range, 33-83 yr). Eight patients had previously undergone surgery elsewhere and showed progressive tumor growth. All 19 patients were treated with SRT: 15 with normal fractions of 1.8-2 Gy single dose up to 54-59.4 Gy. Their irregular tumor volume ranged from 4.2 to 43.1 ccm (average: 14.1 ccm). Hypofractionation with 6 to 7 x 5 Gy was applied in four cases with an average tumor volume of 4.1 ccm (2.2-6.2 ccm). Clinical results and the efficacy for tumor control with an average follow-up of 35 months (11-63 mo) were evaluated. RESULTS: Local tumor control rate was 95% (18 of 19 cases): one patient previously operated on had a recurrence of tumor progression after SRT, followed by a second subtotal resection. A tumor regression was proved in 11 cases (one neuroma disappeared and four patients had tumor shrinkage of more than 50%, the other six experienced shrinkage between 20% and 40%). Within the first 6 months, two patients developed temporarily increased tumor volume as well as a confirmed reaction to irradiation. In one of these two cases, there were mild side effects according to CTC Grade I. No patient experienced a new or increased neurological deficit. Improvement of their cranial nerve disturbances was achieved in 11 of 19 patients and the other eight showed no clinical changes. The mostly moderate trigeminal pain decreased slowly. CONCLUSION: SRT is a low-risk and effective treatment option for intracranial neuromas. Particularly in cases of sinus cavernous-invading trigeminal and in jugular foramen tumors, SRT can be the treatment of choice. Concerning tumor regression, SRT is as effective as RS.

Fractionated stereotactic radiotherapy of glomus jugulare tumors. Local control, toxicity, symptomatology, and quality of life.

BACKGROUND AND PURPOSE: For glomus jugulare tumors, the goal of treatment is microsurgical excision. To minimize postoperative neurologic deficits, stereotactic radiosurgery (SRS) was performed as an alternative treatment option. Stereotactic fractionated radiotherapy (SRT) could be a further alternative. This study aims at the assessment of local control, side effects, and quality of life (QoL). PATIENTS AND METHODS: Between 1999-2005, 17 patients were treated with SRT. 11/17 underwent previous operations. 6/17 received primary SRT. Treatment was delivered by a linear accelerator with 6-MV photons. Median cumulative dose was 57.0 Gy. Local control, radiologic regression, toxicity, and symptomatology were evaluated half-yearly by clinical examination and MRI scans. QoL was assessed by Short Form-36 (SF-36). RESULTS: Median follow-up was 40 months. Freedom from progression and overall survival for 5 years were 100% and 93.8%. Radiologic regression was seen in 5/16 cases, 11/16 patients were stable. Median tumor shrinkage was 17.9% (p=0.14). Severe acute toxicity (grade 3-4) or any late toxicity was never seen. Main symptoms improved in 9/16 patients, 7/16 were stable. QoL was not affected in patients receiving primary SRT. CONCLUSION: SRT offers an additional treatment option of high efficacy with less side effects, especially in cases of large tumors, morbidity, or recurrences after incomplete resections.

Clinicopathologic features of aggressive meningioma emphasizing the role of radiotherapy in treatment.

BACKGROUND AND PURPOSE: Although meningiomas are typically benign, they occasionally behave in an aggressive fashion and carry a less favorable prognosis. The aim of this study was to review the clinical, radiologic and histopathologic features of these aggressive variants as well as the outcome after multimodality therapy. PATIENTS AND METHODS: 16 patients with atypical meningiomas (n = 11) and anaplastic meningiomas (n = 5) were treated in the Departments of Neurosurgery and Radiation Oncology at the University Hospital of Philipps University Marburg, Germany, between 1997 and 2003. Tumor grading was based on new WHO criteria. There were eleven men and five women with a mean age of 54 years. The median follow-up period was 34 months. RESULTS: A total of 24 surgical procedures were performed for these 16 patients. Only seven patients underwent postoperative fractionated stereotactic radiotherapy. Patients with atypical meningioma received radiotherapy only for the recurrent disease. Six patients (37.5%) experienced tumor recurrence after a mean period of 27.2 months in spite of gross total resection. Radiographic findings suggestive of aggressiveness were observed mostly with WHO grade III meningiomas. By comparing the proliferation rate in four cases with atypical meningioma operated twice, the recurrent tumor had a higher proliferation rate than the first tumor in three cases. A special proliferation pattern was noticed in MIB-1 with anaplastic meningiomas. The mean overall survival period was 66.5 months. There was no mortality among patients with atypical meningioma, while four out of five patients with anaplastic meningioma died during follow-up. CONCLUSION: Considering the higher rate of recurrence in aggressive meningiomas even after radical surgical excision and the possibility that the recurrent tumor is more aggressive than the original one, surgery should be combined with postoperative fractionated radiotherapy to improve local tumor control. The peculiar focal expression patterns of anaplastic meningioma in MIB-1 might be a marker of such malignant development.

Stereotactic radiotherapy of meningiomas: symptomatology, acute and late toxicity.

BACKGROUND AND PURPOSE: Stereotactic radiosurgery (SRS) is well established in the treatment of skull base meningiomas, but this therapy approach is limited to small tumors only. The fractionated stereotactic radiotherapy (SRT) offers an alternative treatment option. This study aims at local control, symptomatology, and toxicity. PATIENTS AND METHODS: Between 1997-2003, 224 patients were treated with SRT (n = 183), hypofractionated SRT (n = 30), and SRS (n = 11). 95/224 were treated with SRT/SRS alone. 129/224 patients underwent previous operations. Freedom from progression and overall survival, toxicity, and symptomatology were evaluated systematically. Additionally, tumor volume (TV) shrinkage was analyzed three-dimensionally within the planning system. RESULTS: The median follow-up was 36 months (range, 12-100 months). Overall survival and freedom from progression for 5 years were 92.9% and 96.9%. Quantitative TV reduction was 26.2% and 30.3% 12 and 18 months after SRT/SRS (p < 0.0001). 95.9% of the patients improved their symptoms or were stable. Clinically significant acute toxicity (CTC III degrees ) was rarely seen (2.5%). Clinically significant late morbidity (III degrees -IV degrees ) or new cranial nerve palsies did not occur. CONCLUSION: SRT offers an additional treatment option of high efficacy with only few side effects. In the case of large tumor size (> 4 ml) and adjacent critical structures (< 2 mm), SRT is highly recommended.

Significant tumor volume reduction of meningiomas after stereotactic radiotherapy: results of a prospective multicenter study.

OBJECTIVE: Stereotactic radiosurgery (SRS) is well established in the treatment of cranial base meningiomas. Fractionated stereotactic radiotherapy (SRT) offers an additional treatment option. Data for radiological regression differ, ranging from 13 to 61%. Therefore, the aims of this prospective study were to quantitatively analyze tumor volume (TV) shrinkage and to calculate determining factors. METHODS: Eighty-four patients were examined under equal conditions before and after SRT. Fat-saturated axial T1-weighted contrast-enhanced magnetic resonance imaging scans with 1- to 3-mm slice thickness were used. After image fusion, TV was drawn in each slice to analyze TV shrinkage three-dimensionally by the planning system. RESULTS: Mean TV had shrunk by 33% at 24 months (P = 0.02) and by 36% at 36 months (P = 0.0007) after SRT. With regard to half-year intervals, TV reduction decreased continuously towards a steady state (P < 0.0001). Younger age (P = 0.001) and smaller TV (P = 0.01) are determining factors. There was no correlation between TV reduction, prescribed dose, histological classification, sex, or previous operations. CONCLUSION: Meningiomas shrink significantly after SRT. TV shrinkage declines towards a steady state, which is not yet defined. Younger age and smaller TV are determining factors. Previous operations, sex, prescribed dose, or histological subtypes do not affect TV shrinkage. Eighteen to 24 months after irradiation, when symptoms are clinically stable, is the best time for the first magnetic resonance imaging scans evaluating tumor control and shrinkage.