RESUMO
Gamma Knife Radiosurgery (GKRS) has been reported in the treatment of brainstem metastases while dose volume toxicity thresholds remain mostly undefined. A retrospective review of 52 brainstem metastases in 44 patients treated with GKRS was completed. A median dose of 18 Gy (range 10-22 Gy) was prescribed to the tumor margin (median 50 % isodose). 25 patients had undergone previous whole brain radiation therapy. Toxicity was graded by the LENT-SOMA scale. Mean and median follow-up was 10 and 6 months. Only 3 of the 44 patients are living. Multiple brain metastases were treated in 75 % of patients. Median size of lesions was 0.134 cc, (range 0.013-6.600 cc). Overall survival rate at 1 year was 32 % (95 % CI 51.0-20.1 %) with a median survival time of 6 months (95 % CI 5.0-16.5). Local control rate at 6 months and 1 year was 88 % (95 % CI 70-95 %) and 74 % (95 % CI 52-87 %). Cause of death was neurologic in 17 patients, non-neurologic in 20 patients, and unknown in four. Four patients experienced treatment related toxicities. Univariate analysis of tumor volume revealed that volume greater than 1.0 cc predicted for toxicity. A strategy of using lower marginal doses with GKRS to brain stem metastases appears to lead to a lower local control rate than seen with lesions treated within the standard dose range in other locations. Tumor size greater than 1.0 cc predicted for treatment-related toxicity.
Assuntos
Neoplasias do Tronco Encefálico/secundário , Neoplasias do Tronco Encefálico/cirurgia , Radiocirurgia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Tronco Encefálico/patologia , Neoplasias do Tronco Encefálico/patologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Causas de Morte , Fracionamento da Dose de Radiação , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Carga TumoralRESUMO
BACKGROUND: Gamma knife radiosurgery (GKRS) has been reported as a treatment option for multiple sclerosis (MS)-related trigeminal neuralgia. OBJECTIVE: To report the outcomes of a single-institution retrospective series of MS-related trigeminal neuralgia. METHODS: Between 2002 and 2010, 35 patients with MS-related trigeminal neuralgia were treated with GKRS. The median maximum dose was 90 Gy. Data were analyzed to determine the response to GKRS and factors that may predict for efficacy. RESULTS: Of the 35 patients, 88% experienced a Barrow Neurological Institute (BNI) pain score of I-III at 3 months after GKRS. Kaplan-Meier estimates of 1-, 2- and 5-year freedom from BNI IV-V pain relapse were 57, 57 and 52%, respectively. Numbness was experienced by 39% of patients after GKRS, though no patients reported bothersome numbness. Several differences were noted between how the MS-related variant responded to GKRS and what has previously been reported for idiopathic trigeminal neuralgia. These include the observations that development of post-GKRS numbness did not predict for treatment response (p = 0.62) and that dorsal root entry zone dose did not predict for freedom from pain relapse (odds ratio 1.01, p = 0.1). Active smoking predicted for freedom from pain relapse (odds ratio 67.4, p = 0.04). CONCLUSION: GKRS is a viable noninvasive treatment option for MS-related trigeminal neuralgia.
Assuntos
Esclerose Múltipla/complicações , Radiocirurgia , Neuralgia do Trigêmeo/etiologia , Neuralgia do Trigêmeo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Análise Multivariada , North Carolina , Estudos Retrospectivos , Resultado do TratamentoRESUMO
Atypical meningiomas have poor local control with emerging literature indicating the use of radiosurgery in treatment. The purpose of this study was to evaluate clinical outcomes including local control and failure pattern after Gamma Knife radiosurgery (GKRS) and factors that may affect these outcomes. Between 1999 and 2008, 24 patients were treated with GKRS as either primary or salvage treatment for pathologically proven atypical meningiomas. Treatment failures were determined by serial magnetic resonance imaging. A median marginal dose of 14 Gy was used (range 10.5-18 Gy). Overall local control rates at 1, 2, and 5 years were 75, 51, and 44%, respectively. With median follow-up time of 42.5 months, 14 of 24 patients experienced a treatment failure at time of last follow-up. Eight recurrences were in-field, four were marginal failures, and two were distant failures. Wilcoxon analysis revealed that the conformality index (CI) was a significant predictor of local recurrence (P = 0.04). CI did not predict for distant recurrences (P = 0.16). On multivariate analysis evaluating factors predicting progression free survival, dose >14 Gy was found to be statistically significant (P = 0.01). There appears to be a dose response using GKRS beyond 14 Gy but given the suboptimal local control rates in this study, higher doses may still be needed to obtain better local control.
Assuntos
Neoplasias Meníngeas/mortalidade , Neoplasias Meníngeas/cirurgia , Meningioma/mortalidade , Meningioma/cirurgia , Radiocirurgia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Radiometria , Estudos Retrospectivos , Falha de TratamentoRESUMO
BACKGROUND: Intracranial neoplasms can cause pain similar to trigeminal neuralgia. Literature regarding radiosurgery for this is limited. We present a retrospective review of patients with tumor-related facial pain from benign lesions treated with gamma knife radiosurgery (GKRS) at Wake Forest University. OBJECTIVES: The primary objectives were to determine long-term pain relief and predictive factors for pain alleviation. METHODS: We reviewed 515 patients treated with GKRS for benign meningioma, vestibular schwannoma or trigeminal schwannoma between August 1999 and August 2010. Twenty-one eligible patients had tumor-related facial pain prior to GKRS. The median marginal tumor dose was 12 Gy. Long-term pain relief data were obtained by chart review and telephone interview. RESULTS: The median follow-up for symptom evaluation was 3.8 years. Seventeen of 21 patients (81%) experienced a Barrow Neurological Institute (BNI) score of I-III at 6 months following GKRS. Kaplan-Meier estimates of freedom from BNI IV-V relapse were 66% at 1 year and 53% at 2 years. No pain relapses occurred after 2 years. CONCLUSION: GKRS of benign lesions is a noninvasive option for patients with tumor-related facial pain. Pain relief is modest, with the majority of pain relapses occurring within 2 years and approximately one half of patients maintaining relief beyond 2 years.
Assuntos
Neoplasias Encefálicas/cirurgia , Dor Facial/cirurgia , Meningioma/cirurgia , Neurilemoma/cirurgia , Radiocirurgia/instrumentação , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/complicações , Dor Facial/etiologia , Feminino , Seguimentos , Humanos , Masculino , Meningioma/complicações , Pessoa de Meia-Idade , Neurilemoma/complicações , Medição da Dor , Estudos Retrospectivos , Resultado do TratamentoRESUMO
This work measures and compares the energy spectra of four dosimetrically matched 6 MV beams, generated from four physically different linear accelerators. The goal of this work is twofold. First, this study determines whether the spectra of dosimetrically matched beams are measurably different. This study also demonstrates that the spectra of clinical photon beams can be measured as a part of the beam data collection process for input to a three-dimensional (3D) treatment planning system. The spectra of 6 MV beams that are dosimetrically matched for clinical use were studied to determine if the beam spectra are similarly matched. Each of the four accelerators examined had a standing waveguide, but with different physical designs. The four accelerators were two Varian 2100C/Ds (one 6 MV/18 MV waveguide and one 6 MV/10 MV waveguide), one Varian 600 C with a vertically mounted waveguide and no bending magnet, and one Siemens MD 6740 with a 6 MV/10 MV waveguide. All four accelerators had percent depth dose curves for the 6 MV beam that were matched within 1.3%. Beam spectra were determined from narrow beam transmission measurements through successive thicknesses of pure aluminum along the central axis of the accelerator, made with a graphite Farmer ion chamber with a Lucite buildup cap. An iterative nonlinear fit using a Marquardt algorithm was used to find each spectrum. Reconstructed spectra show that all four beams have similar energy distributions with only subtle differences, despite the differences in accelerator design. The measured spectra of different 6 MV beams are similar regardless of accelerator design. The measured spectra show excellent agreement with those found by the auto-modeling algorithm in a commercial 3D treatment planning system that uses a convolution dose calculation algorithm. Thus, beam spectra can be acquired in a clinical setting at the time of commissioning as a part of the routine beam data collection.
Assuntos
Aceleradores de Partículas , Planejamento da Radioterapia Assistida por Computador/métodos , Algoritmos , Elétrons , Desenho de Equipamento , Grafite , Íons , Modelos Estatísticos , Fótons , Controle de Qualidade , Dosagem Radioterapêutica , Radioterapia de Alta EnergiaRESUMO
Because of geometrical limitations in the helmet of the Leksell Gamma Knife(Elekta Corp., Atlanta, GA, USA) certain regions within the cranium cannot be targeted for treatment. We describe a method by which lesions in these regions can be treated with the Varian-Zmed stereotactic radiosurgery system utilizing an infrared optical positioning system attached to a Leksell head frame. We have measured the accuracy of the optical tracking system using a phantom attached to a Leksell frame and have determined that the system can target a linear accelerator radiosurgery beam to an accuracy of within 1 millimeter.
Assuntos
Radiocirurgia/instrumentação , Radiocirurgia/métodos , Humanos , Imageamento por Ressonância Magnética , Tomógrafos ComputadorizadosRESUMO
OBJECT: Gamma Knife surgery (GKS) is a treatment option for patients with refractory typical trigeminal neuralgia (TN), TN with atypical features, and atypical types of facial pain. The Gamma Knife's 201 60Co sources decay with a half-life of 5.26 years. The authors examined whether the decrease in dose rate over 4.6 years between Co source replacements affected the control rates of facial pain in patients undergoing GKS. METHODS: The authors collected complete follow-up data on 239 of 326 GKS procedures performed in patients with facial pain. Patients were classified by their type of pain. The isocenter of a 4-mm collimator helmet was targeted at the proximal trigeminal nerve root, and the dose (80-90 Gy) was prescribed at the 100% isodose line. Patients reported the amount of pain control following radiosurgery by answering a standardized questionnaire. Eighty percent of patients experienced greater than 50% pain relief, and 56% of patients experienced complete pain relief after GKS. Neither dose rate nor treatment time was significantly associated with either the control rate or degree of pain relief. A significant association between the type of facial pain and the pain control rate after GKS was observed (p < 0.001; Pearson chi-square test). In their statistical analysis, the authors accounted for changes in prescription dose over time to prevent the dose rate from being a confounding variable. There was no observable effect of the dose rate or of the treatment duration within the typical period to source replacement. CONCLUSIONS: Patients with facial pain appear to receive consistent treatment with GKS at any time during the first half-life of the Co sources.
Assuntos
Radioisótopos de Cobalto , Dor Facial/cirurgia , Radiocirurgia , Neuralgia do Trigêmeo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Meia-Vida , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor , Radioatividade , Resultado do TratamentoRESUMO
OBJECT: Salvage treatment of large, symptomatic brain metastases after failure of whole-brain radiotherapy (WBRT) remains challenging. When these lesions require resection, there are few options to lower expected rates of local recurrence at the resection cavity margin. The authors describe their experience in using Gamma Knife surgery (GKS) to target the resection cavity in patients whose tumors had progressed after WBRT. METHODS: The authors retrospectively identified 143 patients in whom GKS had been used to target a brain metastasis resection cavity between 2000 and 2005. Seventy-nine of these patients had undergone WBRT prior to resection and GKS. The median patient age was 53 years, and the median prescribed dose was 18 Gy (range 8-24 Gy), with resection cavities of relatively larger volume (> 15 cm3). The GKS dose was prescribed at the 40 to 95% isodose contour (mode 50%). Local recurrence within 1 cm of the treatment volume occurred in four (5.1%) of 79 cases. The median duration of time to local recurrence was 6.1 months (range 2-13 months). The median duration of time to occurrence of distant metastases following GKS of the resection cavity was 10.8 months (range 2-86 months). Carcinomatous meningitis developed in four (5.1%) of 79 cases. Symptomatic radionecrosis requiring surgical treatment occurred in three (3.8%) of 79 cases. The median duration of survival following GKS of the resection cavity was 69.6 weeks. The median 2- and 5-year survival rates were 20.2 and 6.3%, respectively. CONCLUSIONS: When metastases progress after WBRT and require resection, GKS targeting the resection cavity is a viable strategy. In 75 (94.9%) of 79 cases, GKS of the resection cavity in patients in whom WBRT had failed appears to have achieved its goal of local disease control.
Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Recidiva Local de Neoplasia/prevenção & controle , Radiocirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/radioterapia , Estudos de Coortes , Intervalo Livre de Doença , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/mortalidade , Retratamento , Estudos Retrospectivos , Falha de TratamentoRESUMO
PURPOSE: To describe the relationship between two commonly used dosimetric quantifiers (dose received by 90% of the prostate [D(90)] and volume receiving 100% of dose [V(100)]) and biochemical disease-free survival (bDFS) in a cohort of men treated with low-dose-rate prostate brachytherapy (LDRPB). METHODS AND MATERIALS: The information in this report concerned the first 63 men treated with LDRPB alone at our institution between September 1997 and September 1998. All men had histologically confirmed, clinically localized prostate cancer. All men were treated with(125)I. The prescription dose was 144 Gy according to the Task Group 43 formalism. LDRPB was performed jointly by a radiation oncologist and urologist. Dosimetric quantifiers (D(90), V(100)) were calculated from a CT scan performed 1 month after LDRPB. Biochemical recurrence was defined according to the American Society for Therapeutic Radiology and Oncology consensus definition. Biochemical relapse-free survival (bRFS) was estimated using the product-limit method. D(90) and V(100) were examined as putative covariates for bRFS using the proportional hazards regression method. All p values are two-sided. RESULTS: The median follow-up for the entire cohort was 62 months. The median D(90) was 122 Gy (range, 57-171Gy), and in 16 (25%) of 63 patients, the calculated D(90) was >140 Gy. The median V(100) was 81% (range, 51-97%). Nine men developed evidence of biochemical relapse at a median of 19 months (range, 6-38 months). The 5-year estimate of bRFS was 85% (95% confidence interval, 80-90%). The 5-year estimates of bRFS according to D(90) were as follows: D(90) > or =140 Gy, 86%; D(90) <140 Gy, 84% (p = not statistically significant). No threshold value of D(90) was predictive of the 5-year estimates of bRFS until the D(90) was <80 Gy (D(90) > or =80 Gy, 89%; D(90) <80 Gy, 50%; p = 0.02). The 5-year estimates of bRFS according to V(100) were as follows: V(100) > or =85%, 87%; V(100) <85%, 84% (p = not statistically significant). No threshold value of V(100) was predictive of the 5-year estimates of BRFS unless the dosimetry was particularly poor. The 5-year BRFS was 89% if the V(100) was > or =65% compared with 40% if the V(100) was <65% (p = 0.006). CONCLUSION: The dosimetric or quantifiers described in this report did not predict for bRFS after LDRPB unless the dosimetry was very poor. This finding is not in complete agreement with those of previous reports. Possible reasons for this observation are (1) the study in underpowered, (2) inherent measurement error, (3) dosimetric quantifiers are poor surrogates of the dose received by the cancer, and (4) length of follow-up. Additional work in the area of quality assessment after LDRPB is required.
Assuntos
Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Idoso , Análise de Variância , Relação Dose-Resposta à Radiação , Seguimentos , Humanos , Radioisótopos do Iodo/uso terapêutico , Masculino , Pessoa de Meia-Idade , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Análise de RegressãoRESUMO
PURPOSE: The purpose of the present report is to describe the relationship between two dosimetric quantifiers (V(100) and D(90)) and freedom from biochemical recurrence (FFBR) in a cohort of men treated with low-dose-rate prostate brachytherapy (LDRPB) alone. METHODS AND MATERIALS: One hundred three men were treated with LDRPB alone between September 1997 and December 1999. All men had histologically confirmed clinically localized prostate cancer. Fifty-nine percent of the cohort had low-risk disease (defined as PSA<10, Gleason <7, and T stage
Assuntos
Braquiterapia , Neoplasias da Próstata/radioterapia , Carga Tumoral/efeitos da radiação , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Biomarcadores Tumorais/sangue , Relação Dose-Resposta à Radiação , Seguimentos , Humanos , Radioisótopos do Iodo/administração & dosagem , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Antígeno Prostático Específico/sangue , Antígeno Prostático Específico/efeitos da radiação , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Radiometria , Dosagem Radioterapêutica , Eficiência Biológica Relativa , Estudos Retrospectivos , Fatores de Risco , Tomografia Computadorizada por Raios X , Resultado do TratamentoRESUMO
BACKGROUND AND PURPOSE: Reports using the retropubic and transperineal technique of prostate brachytherapy suggest that adequate radiation doses are required for good clinical results with I-125. After 3 years of using loose sources (LS), radioactive sources embedded in suture (SES) were introduced into our prostate brachytherapy technique. The purpose of the present report is to determine whether dosimetric quantifiers of implant adequacy were affected by the use of SES. MATERIALS AND METHODS: Between September 1999 and April 2000, 20 patients were treated with prostate brachytherapy alone with a preplanned, preloaded needle technique using LS. Between May 2000 and February 2001, 20 patients were treated with prostate brachytherapy alone with a preplanned, preloaded needle technique using SES. Dosimetric quantifiers (DQ) of implant adequacy were calculated using a computed tomography scan performed 1 month following prostate brachytherapy. DQ were compared between patients treated with LS and patients treated with SES. RESULTS: The demographic characteristics were similar for each group. Men treated with SES had slightly smaller prostate glands compared to men treated with LS. The mean total activity and activity per seed were similar for each group but the activity per unit volume was slightly higher for the SES group. Patients treated with SES were found to have significantly improved DQ compared to patients treated with LS. The mean V100 for patients treated with SES was 94.10% compared to 86.54% in those patients treated with LS (P<0.001). CONCLUSIONS: In our experience using preplanning and preloaded needles, the use of SES is associated with improved postimplant DQ.
Assuntos
Braquiterapia/instrumentação , Braquiterapia/métodos , Neoplasias da Próstata/radioterapia , Idoso , Distribuição de Qui-Quadrado , Humanos , Radioisótopos do Iodo/administração & dosagem , Masculino , Radiometria , Dosagem Radioterapêutica , Técnicas de Sutura , Resultado do TratamentoRESUMO
We have investigated the use of an adapter that permits the use of a Leksell coordinate frame with a linear accelerator stereotactic radiosurgery system based on the Brown-Robert-Wells (BRW) design. This device is useful when lesions that are planned for treatment on a Leksell Gamma Knife system are found to be inaccessible to the Gamma Knife. We have found that with this device objects within a head phantom can be targeted by the linear accelerator within an accuracy of approximately 1 mm.
Assuntos
Encéfalo/cirurgia , Análise de Falha de Equipamento/métodos , Radiocirurgia/instrumentação , Terapia Combinada/instrumentação , Imagens de Fantasmas , Radiocirurgia/métodos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
PURPOSE: To examine the relationship between calculated doses to the neurovascular bundles (NVBs) and the penile bulb (PB) and the development of erectile dysfunction (ED) after low-dose-rate prostate brachytherapy (LDRPB) alone. METHODS AND MATERIALS: Between September 1997 and June 1999, 84 men were treated with LDRPB alone. Inclusion criteria for this study were (1) no ED according to a self-administered questionnaire before PB, (2) treatment with PB alone (125I; 144 Gy), (3) postimplant CT scan of the prostate 1 month after PB, and (4) minimum of 24 months of continuous follow-up. Fifty men met all inclusion criteria. ED was assessed by a self-administered questionnaire completed before and at each follow-up visit after LDRPB. Radiation doses to the NVB and PB were calculated on the basis of axial postimplant CT images. Multiple variables (patient-related and dosimetric quantifiers) that may predict for the development of ED were examined by univariate analysis. RESULTS: Thirty of the 50 men (60%) were potent at last follow-up. The only patient-related variable that predicted for the development of ED was patient age (<65 vs. >65 years; p=0.03). The calculated mean maximum doses to the NVB and PB were 684 Gy (range, 195-1277 Gy) and 498 Gy (range, 44-971 Gy), respectively. The mean calculated doses to 50% of the NVB and PB were 158 Gy (range, 76-240 Gy) and 43 Gy (range, 19-101 Gy), respectively. The calculated mean maximum, mean minimum, and mean doses to 50% of the NVB or PB did not differ between those men who developed ED and those men who did not develop ED. None of the dosimetric variables examined predicted the development of ED after LDRPB. CONCLUSIONS: In our experience, higher calculated doses to the NVB or PB are not associated with ED after LDRPB.
Assuntos
Braquiterapia/efeitos adversos , Disfunção Erétil/etiologia , Pênis/efeitos da radiação , Próstata/efeitos da radiação , Neoplasias da Próstata/radioterapia , Idoso , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Prognóstico , Próstata/irrigação sanguínea , Próstata/inervação , Dosagem RadioterapêuticaRESUMO
BACKGROUND: Gamma Knife radiosurgery (GKRS) has been reported to be an effective modality to treat trigeminal neuralgia. OBJECTIVE: To determine predictive factors for the successful treatment of trigeminal neuralgia with GKRS. METHODS: Between 1999 and 2008, 777 GKRS procedures for patients with trigeminal neuralgia were performed at our institution. Evaluable follow-up data were obtained for 448 patients. Median follow-up time was 20.9 months (range, 3-86 months). The mean maximum prescribed dose was 88 Gy (range, 80-97 Gy). Dosimetric variables recorded included dorsal root entry zone dose, pons maximum dose, dose to the petrous dural ridge, and cisternal nerve length. RESULTS: By 3 months after GKRS, 86% of patients achieved Barrow Neurologic Institute I to III pain scores, with 43% of patients achieving a Barrow Neurologic Institute I pain score. Twenty-six percent of patients reported posttreatment facial numbness; 28% of patients reported a post-GKRS procedure for relapsed pain, and median time to next procedure was 4.4 years. Multivariate analysis revealed that the development of postsurgical numbness (odds ratio [OR], 2.76; P = .006) was the dominant factor predictive of efficacy. Longer cisternal nerve length (OR, 0.85; P = .005), prior radiofrequency ablation (OR, 0.35; P = .028), and diabetes mellitus (OR, 0.38; P = .013) predicted decreased efficacy. The mean dose delivered to the dorsal root entry zone dose in patients who developed facial numbness (57.6 Gy) was more than the mean dose (47.3 Gy) given to patients who did not develop numbness (P = .02). CONCLUSION: The development of post-GKRS facial numbness is a dominant factor that predicts for efficacy of GKRS. History of diabetes mellitus or previous radiofrequency ablation may portend worsened outcome.
Assuntos
Complicações Pós-Operatórias/epidemiologia , Radiocirurgia/efeitos adversos , Radiocirurgia/estatística & dados numéricos , Neuralgia do Trigêmeo/epidemiologia , Neuralgia do Trigêmeo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Doses de Radiação , Fatores de Risco , Resultado do Tratamento , Adulto JovemRESUMO
PURPOSE: Radiosurgery has been successfully used in selected cases to avoid repeat whole-brain irradiation (WBI) in patients with multiple brain metastases of most solid tumor histological findings. Few data are available for the use of radiosurgery for small-cell lung cancer (SCLC). METHODS AND MATERIALS: Between November 1999 and June 2009, 51 patients with SCLC and previous WBI and new brain metastases were treated with GammaKnife stereotactic radiosurgery (GKSRS). A median dose of 18 Gy (range, 10-24 Gy) was prescribed to the margin of each metastasis. Patients were followed with serial imaging. Patient electronic records were reviewed to determine disease-related factors and clinical outcomes after GKSRS. Local and distant brain failure rates, overall survival, and likelihood of neurologic death were determined based on imaging results. The Kaplan-Meier method was used to determine survival and local and distant brain control. Cox proportional hazard regression was performed to determine strength of association between disease-related factors and survival. RESULTS: Median survival time for the entire cohort was 5.9 months. Local control rates at 1 and 2 years were 57% and 34%, respectively. Distant brain failure rates at 1 and 2 years were 58% and 75%, respectively. Fifty-three percent of patients ultimately died of neurologic death. On multivariate analysis, patients with stable (hazard ratio [HR] = 2.89) or progressive (HR = 6.98) extracranial disease (ECD) had worse overall survival than patients without evidence of ECD (p = 0.00002). Concurrent chemotherapy improved local control (HR = 89; p = 0.006). CONCLUSIONS: GKSRS represents a feasible salvage option in patients with SCLC and brain metastases for whom previous WBI has failed. The status of patients' ECD is a dominant factor predictive of overall survival. Local control may be inferior to that seen with other cancer histological results, although the use of concurrent chemotherapy may help to improve this.
Assuntos
Neoplasias Encefálicas/secundário , Neoplasias Encefálicas/cirurgia , Neoplasias Pulmonares , Radiocirurgia/métodos , Terapia de Salvação/métodos , Carcinoma de Pequenas Células do Pulmão/secundário , Carcinoma de Pequenas Células do Pulmão/cirurgia , Adulto , Idoso , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/radioterapia , Irradiação Craniana/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Radiocirurgia/instrumentação , Dosagem Radioterapêutica , Estudos Retrospectivos , Carcinoma de Pequenas Células do Pulmão/mortalidade , Carcinoma de Pequenas Células do Pulmão/radioterapia , Análise de Sobrevida , Falha de TratamentoRESUMO
BACKGROUND: It has been well established that Gamma Knife radiosurgery (GKS) is an effective treatment for brain arteriovenous malformations (AVMs). OBJECTIVE: To evaluate complete obliteration rates for magnetic resonance imaging (MRI)-based GKS treatment planning performed with and without angiography and to conduct a preliminary assessment of the utility of using pulsed arterial spin labeling (PASL) magnetic resonance (MR) perfusion imaging to confirm complete obliteration. METHODS: Forty-six patients were identified who had undergone GKS without embolization with a minimum follow-up of 2 years. One group was planned with integrated stereotactic angiography and MR (spoiled gradient recalled) images obtained on the day of GKS. A second technique avoided the risk of arteriography by using only axial MR images. Beginning in 2007, PASL MR perfusion imaging was routinely performed as a portion of the follow-up MRI to assess the restoration of normal blood flow of the nidus and surrounding area. RESULTS: The overall obliteration rate for the angiography/MRI group was 88.0% (29 of 33). Patients in the MRI-only group had an obliteration rate of 61.5% (8 of 13), with P=.092 with the Fisher exact test, which is not statistically significant. A Kaplan-Meier analysis was also not statistically significant (log rank test, P=.474). Four of 9 patients with incomplete obliteration on angiography also had shown residual abnormal blood flow on PASL imaging. CONCLUSION: This retrospective analysis shows that treatment planning technique used in GKS does not play a role in the eventual obliteration of treated AVMs. PASL may have potential in the evaluation of AVM obliteration.
Assuntos
Malformações Arteriovenosas Intracranianas/diagnóstico , Malformações Arteriovenosas Intracranianas/cirurgia , Imageamento por Ressonância Magnética , Radiocirurgia/métodos , Adolescente , Adulto , Idoso , Pressão Arterial , Angiografia Cerebral , Criança , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Marcadores de Spin , Resultado do Tratamento , Adulto JovemRESUMO
OBJECT: As a strategy to delay or avoid whole-brain radiotherapy (WBRT) after resection of a brain metastasis, the authors used high-resolution MR imaging and cavity-directed radiosurgery for the detection and treatment of further metastases. METHODS: Between April 2001 and October 2009, 112 resection cavities in 106 patients with no prior WBRT were treated using radiosurgery directed to the tumor cavity and for any synchronous brain metastases detected on high-resolution MR imaging at the time of radiosurgical planning. A median dose of 17 Gy to the 50% isodose line was prescribed to the gross tumor volume, defined as the rim of enhancement around the resection cavity. Patients were followed up via serial imaging, and new brain metastases were generally treated using additional radiosurgery, with salvage WBRT typically reserved for local treatment failure at a resection cavity, numerous failures, or failures occurring at short time intervals. Local and distant treatment failures were determined based on imaging results. Kaplan-Meier curves were generated to estimate local and distant treatment failure rates, overall survival, neurological cause-specific survival, and time delay to salvage WBRT. RESULTS: Radiosurgery was delivered to the resection cavity alone in 57.5% of patients, whereas 24.5% of patients also received treatment for 1 synchronous metastasis, 11.3% also received treatment for 2 synchronous metastases, and 6.6% also received treatment for 3-10 additional lesions. The median overall survival was 10.9 months. Overall survival at 1 year was 46.8%. The local tumor control rate at 1 year was 80.3%. The disease control rate in distant regions of the brain at 1 year was 35.4%, with a median time of 6.9 months to distant failure. Thirty-nine of 106 patients eventually received salvage WBRT, and the median time to salvage WBRT was 12.6 months. Kaplan-Meier estimates showed that the rate of requisite WBRT at 1 year was 45.9%. Neurological cause-specific survival at 1 year was 50.1%. Leptomeningeal failure occurred in 8 patients. One patient had treatment failure within the resection tract. Seven patients required reoperation: 2 for resection cavity recurrence, 3 for radiation necrosis, 1 for hydrocephalus, and 1 for a CSF cutaneous fistula. On multivariate analysis, a preoperative tumor diameter > 3 cm was predictive of local treatment failure. CONCLUSIONS: Cavity-directed radiosurgery combined with high-resolution MR imaging detection and radiosurgical treatment of synchronous brain metastases is an effective strategy for delaying and even foregoing WBRT in most patients. This technique provides acceptable local disease control, although distant treatment failure remains significant.
Assuntos
Neoplasias Encefálicas/cirurgia , Encéfalo/cirurgia , Radiocirurgia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/secundário , Feminino , Humanos , Estimativa de Kaplan-Meier , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Radioterapia Adjuvante , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do TratamentoRESUMO
PURPOSE: To assess toxicity in patients with either a collagen vascular disease (CVD) or multiple sclerosis (MS) treated with intracranial radiosurgery. METHODS AND MATERIALS: Between January 2004 and April 2009, 6 patients with MS and 14 patients with a CVD were treated with Gamma Knife radiosurgery (GKRS) for intracranial tumors. Treated lesions included 15 total brain metastases in 7 patients, 11 benign brain tumors, 1 low grade glioma, and 1 cavernous malformation. Toxicities were graded by the Radiation Therapy Oncology Group Acute/Late Radiation Morbidity Scoring Criteria. "Rare toxicities" were characterized as those reported in the scientific literature at an incidence of <5%. RESULTS: Median follow-up time was 16 months. Median dose to the tumor margin was 13.0 Gy (range, 12-21 Gy). Median size of tumor was 5.0 cm(3) (range, 0.14-7.8 cm(3)). Of the 14 patients with CVD, none experienced a Grade 3 or 4 toxicity or a toxicity characterized as rare. Of the 6 patients with MS, 3 experienced rare toxicities, and two of these were Grade 3 toxicities. Rare complications included a patient experiencing both communicating hydrocephalus and facial nerve palsy, as well as 2 additional patients with motor cranial nerve palsy. High-grade toxicities included the patient with an acoustic neuroma requiring ventriculoperitoneal shunt placement for obstructive hydrocephalus, and 1 patient with a facial nerve schwannoma who experienced permanent facial nerve palsy. Interval between radiosurgery and high-grade toxicities ranged from 1 week to 4 months. CONCLUSIONS: Our series suggests that patients with MS who receive GKRS may be at increased risk of rare and high-grade treatment-related toxicity. Given the time course of toxicity, treatment-related edema or demyelination represent potential mechanisms.
Assuntos
Neoplasias Encefálicas/cirurgia , Doenças do Colágeno/complicações , Esclerose Múltipla/complicações , Radiocirurgia/efeitos adversos , Doenças Vasculares/complicações , Adulto , Idoso , Artrite Reumatoide/complicações , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Irradiação Craniana/efeitos adversos , Irradiação Craniana/métodos , Paralisia Facial/etiologia , Feminino , Seguimentos , Glioma/complicações , Glioma/cirurgia , Humanos , Hidrocefalia , Malformações Arteriovenosas Intracranianas/complicações , Malformações Arteriovenosas Intracranianas/cirurgia , Lúpus Eritematoso Sistêmico/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Estudos Retrospectivos , Carga Tumoral/efeitos da radiaçãoRESUMO
PURPOSE: Repeat gamma knife stereotactic radiosurgery (GKRS) for recurrent or persistent trigeminal neuralgia induces an additional response but at the expense of an increased incidence of facial numbness. The present series summarized the results of a repeat treatment series at Wake Forest University Baptist Medical Center, including a multivariate analysis of the data to identify the prognostic factors for treatment success and toxicity. METHODS AND MATERIALS: Between January 1999 and December 2007, 37 patients underwent a second GKRS application because of treatment failure after a first GKRS treatment. The mean initial dose in the series was 87.3 Gy (range, 80-90). The mean retreatment dose was 84.4 Gy (range, 60-90). The dosimetric variables recorded included the dorsal root entry zone dose, pons surface dose, and dose to the distal nerve. RESULTS: Of the 37 patients, 81% achieved a >50% pain relief response to repeat GKRS, and 57% experienced some form of trigeminal dysfunction after repeat GKRS. Two patients (5%) experienced clinically significant toxicity: one with bothersome numbness and one with corneal dryness requiring tarsorraphy. A dorsal root entry zone dose at repeat treatment of >26.6 Gy predicted for treatment success (61% vs. 32%, p = .0716). A cumulative dorsal root entry zone dose of >84.3 Gy (72% vs. 44%, p = .091) and a cumulative pons surface dose of >108.5 Gy (78% vs. 44%, p = .018) predicted for post-GKRS numbness. The presence of any post-GKRS numbness predicted for a >50% decrease in pain intensity (100% vs. 60%, p = .0015). CONCLUSION: Repeat GKRS is a viable treatment option for recurrent trigeminal neuralgia, although the patient assumes a greater risk of nerve dysfunction to achieve maximal pain relief.
Assuntos
Hipestesia/etiologia , Radiocirurgia/efeitos adversos , Nervo Trigêmeo/efeitos da radiação , Neuralgia do Trigêmeo/cirurgia , Feminino , Humanos , Masculino , Análise Multivariada , Medição da Dor , Ponte/efeitos da radiação , Dosagem Radioterapêutica , Recidiva , Retratamento/métodos , Estudos Retrospectivos , Raízes Nervosas Espinhais/efeitos da radiaçãoRESUMO
PURPOSE: To investigate the efficacy of 3.0-T magnetic resonance imaging (MRI) for detecting brain metastases for stereotactic radiosurgery (SRS) planning. METHODS AND MATERIALS: All adult patients scheduled for SRS treatment for brain metastases at our institution between October 2005 and January 2008 were eligible for analysis. All patients underwent radiosurgery treatment planning 3.0-T MRI on the day of scheduled radiosurgery and a diagnostic 1.5-T MRI in the days or weeks prior to radiosurgery for comparison. Both scans were interpreted by neuroradiologists who reported their findings in the radiology reports. We performed a retrospective review of the radiology reports to determine the number of brain metastases identified using each MRI system. RESULTS: Of 254 patients scheduled for treatment from October 2005 to January 2008, 138 patients had radiology reports that explicitly described the number of metastases identified on both scans. With a median interval of 17 days (range, 1-82) between scans, the number of metastases detected using 1.5-T MRI system ranged from 1 to 5 and from 1 to 8 using the 3.0 T-MRI system. Twenty-two percent of patients were found to have a greater number of metastases with the 3.0 T-MRI system. The difference in number of metastases detected between the two scans for the entire cohort ranged from 0 to 6. Neither histology (p = 0.52 by chi-sq test) nor time between scans (p = 0.62 by linear regression) were significantly associated with the difference in number of metastases between scans. CONCLUSIONS: The 3.0-T MRI system appears to be superior to a 1.5-T MRI system for detecting brain metastases, which may have significant implications in determining the appropriate treatment modality. Our findings suggest the need for a prospectively designed study to further evaluate the use of a 3.0 T-MRI system for stereotactic radiosurgery planning in the treatment of brain metastases.