Gamma Knife radiosurgery for the treatment of trigeminal neuralgia: A single center-experience.

INTRODUCTION AND OBJECTIVES: We aimed to assess the outcomes of patients with trigeminal neuralgia (TGN) who underwent Gamma Knife radiosurgery (GKRS). MATERIALS AND METHODS: Fifty-three patients with typical TGN underwent GKRS from May 2012 until December 2022. Among these patients, 45 patients who were follow-up for at least 12 months were included in the study. A mean dose of 87.5 Gy (range, 80-90) was administered to the trigeminal nerve. Postoperatively, outcome was considered excellent if the patient was pain- and medication-free. RESULTS: The mean symtpom duration was 9.53 years, and the mean patient age was 59.8 years (range, 34-85). The mean follow-up period was 46.8 months (range, 12-127 months). 46.7% of patients had a history of previous surgical interventions. A single nerve division was affected in 14 patients (31.1%), and multiple divisions were affected in 31 patients (68.9%). The rate of initial pain relief was 80%. Hypoesthesia in the area of trigeminal nerve developed in 30 (66.7%). Twenty patients (44.4%) exhibited excellent results within 72.4 months. Recurrence occurred in 11 patients (24.4%) with 27.6 months. CONCLUSIONS: Our results suggest that GKRS is a safe and effective procedure. Thus, it is an attractive first- and second-line treatment choice for TGN.

Challenges in radiological evaluation of brain metastases, beyond progression.

MRI is the cornerstone in the evaluation of brain metastases. The clinical challenges lie in discriminating metastases from mimickers such as infections or primary tumors and in evaluating the response to treatment. The latter sometimes leads to growth, which must be framed as pseudo-progression or radionecrosis, both inflammatory phenomena attributable to treatment, or be considered as recurrence. To meet these needs, imaging techniques are the subject of constant research. However, an exponential growth after radiotherapy must be interpreted with caution, even in the presence of results suspicious of tumor progression by advanced techniques, because it may be due to inflammatory changes. The aim of this paper is to familiarize the reader with inflammatory phenomena of brain metastases treated with radiotherapy and to describe two related radiological signs: "the inflammatory cloud" and "incomplete ring enhancement", in order to adopt a conservative management with close follow-up.

Tratamiento multimodal en los schwanomas vestibulares grandes / Multimodal Treatment for Large Vestibular Schwannomas

Introducción: Los schwanomas vestibulares son lesiones clasificadas como grado I por la Organización Mundial de la Salud. Las opciones conductuales incluyen la observación, la radiocirugía o la resección microquirúrgica endoscópica. Objetivo: Describir el rol del tratamiento multimodal en los schwanomas vestibulares. Métodos: Se realizó una búsqueda sistemática de literatura médica para la identificación e inclusión de artículos en las siguientes bases de datos: PubMed/Medline, SciELO y Google Scholar, además de los servidores de preprints BioRvix y MedRvix. Se usaron los siguientes descriptores: vestibular schwanoma OR acoustic neuroma AND nerve centered approach OR combined approach AND partial resection OR subtotal resection OR near total resection. Se excluyeron editoriales, cartas al editor, libros, revisiones, metaanálisis y aquellos artículos con método deficiente de más de 20 años de publicación o sin mención al tema de interés. Fueron incluidos 16 artículos. Desarrollo: Los artículos incluyeron un total de 699 pacientes, de los cuales solo 228 (32,6 porciento) recibieron radioterapia en el período posoperatorio. El período de seguimiento promedió 49,6 meses. La preservación de la función facial se logró en el 88,3 porciento de los casos y el control tumoral en el 80,7 porciento. El estado de la preservación auditiva solo fue informado en el 50 porciento de los estudios. El uso de la radioterapia adyuvante mostró gran variabilidad. Conclusiones: El tratamiento multimodal para los schwanomas vestibulares grandes -compuesto por la resección subtotal, vaciamiento intratumoral, seguido de radiocirugía- se ha convertido en una opción plausible. Se necesita la publicación de mayor cantidad de reportes para ofrecer recomendaciones y estratificar la conducta(AU)

Introduction: Vestibular schwannomas are lesions classified as grade I by the World Health Organization. Behavioral options include observation, radiosurgery or endoscopic microsurgical resection. Objective: To describe the role of multimodal treatment for vestibular schwannomas. Methods: A systematic search of medical literature, for the identification and inclusion of articles, was carried out in the databases PubMed/Medline, SciELO and Google Scholar, as well as in the preprint servers BioRvix and MedRvix. The following descriptors were used: vestibular schwannoma OR acoustic neuroma AND nerve centered approach OR combined approach AND partial resection OR subtotal resection OR near total resection. Editorials, letters to the editor, books, reviews and metaanalyses were excluded, as well as articles with deficient method of more than 20 years of publication or not mentioning the topic of interest. Sixteen articles were included. Development: The articles included a total of 699 patients, of which only 228 (32.6 ) received radiotherapy in the postoperative period. The average follow-up period was 49.6 months. Preservation of facial function was achieved in 88.3 percent of cases; and tumor control, in 80.7 percent. Hearing preservation status was reported in only 50 percent of the studies. The usage of adjuvant radiotherapy showed great variability. Conclusions: Multimodal treatment for large vestibular schwannomas -composed of subtotal resection and intratumoral draining, followed by radiosurgery- has become a plausible option. The publication of a greater amount of reports is necessary to provide recommendations and stratify the behavior(AU)

Current uses and applications of stereotactic body radiation therapy.

Stereotactic body radiation therapy (SBRT) is a modality that delivers high doses of radiation to a well-defined tumor target in a single or a few fractions and with high precision, which significantly reduces the dose received by surrounding normal tissues. SBRT is indicated for inoperable, early stage (T1 and T2) primary non-small cell lung cancer, lung metastases with a controlled primary tumor, prostate tumors and oligometastatic disease. Despite the lack of long-term or phase III studies, efficacy results in local control are higher than 90%, with similar toxicity to that reported with conventional fractionated radiotherapy. This article describes SBRT technology and technique, along with clinical applications, indications and limitations of this therapeutic modality.

La radioterapia corporal estereotáctica es una modalidad que con alta precisión administra dosis alta de radiación a un objetivo tumoral bien definido, en una o en pocas fracciones, y reduce significativamente la dosis que reciben los tejidos sanos circundantes. Está indicada en cáncer primario de pulmón de células no pequeñas en estadios tempranos (T1 y T2) no operable, metástasis pulmonares con un tumor primario controlado, tumores prostáticos y enfermedad oligometastásica. A pesar de la falta de estudios a largo plazo o fase III, los resultados de su eficacia en el control local es superior a 90 %, con toxicidad similar a la reportada con fraccionamientos convencionales de radioterapia. Este artículo describe la tecnología y la técnica de radioterapia corporal estereotáctica, con las aplicaciones clínicas, indicaciones y limitaciones de esta modalidad terapéutica.

Usos y aplicaciones actuales de la radioterapia corporal estereotáctica / Current uses and applications of stereotactic body radiation therapy

Resumen La radioterapia corporal estereotáctica es una modalidad que con alta precisión administra dosis alta de radiación a un objetivo tumoral bien definido, en una o en pocas fracciones, y reduce significativamente la dosis que reciben los tejidos sanos circundantes. Está indicada en cáncer primario de pulmón de células no pequeñas en estadios tempranos (T1 y T2) no operable, metástasis pulmonares con un tumor primario controlado, tumores prostáticos y enfermedad oligometastásica. A pesar de la falta de estudios a largo plazo o fase III, los resultados de su eficacia en el control local es superior a 90 %, con toxicidad similar a la reportada con fraccionamientos convencionales de radioterapia. Este artículo describe la tecnología y la técnica de radioterapia corporal estereotáctica, con las aplicaciones clínicas, indicaciones y limitaciones de esta modalidad terapéutica.

Abstract Stereotactic body radiation therapy (SBRT) is a modality that delivers high doses of radiation to a well-defined tumor target in a single or a few fractions and with high precision, which significantly reduces the dose received by surrounding normal tissues. SBRT is indicated for inoperable, early stage (T1 and T2) primary non-small cell lung cancer, lung metastases with a controlled primary tumor, prostate tumors and oligometastatic disease. Despite the lack of long-term or phase III studies, efficacy results in local control are higher than 90%, with similar toxicity to that reported with conventional fractionated radiotherapy. This article describes SBRT technology and technique, along with clinical applications, indications and limitations of this therapeutic modality.

Cerebellopontine angle meningiomas: LINAC stereotactic radiosurgery treatment.

OBJECTIVES: To evaluate the efficacy of treatment with linear accelerator-based stereotactic radiosurgery (LINAC) in cerebellopontine angle meningiomas. METHODS: We analyzed 80 patients diagnosed with cerebellopontine angle meningiomas between 2001 and 2014, treated with stereotactic radiosurgery (SRS), of whom 81.9% (n=68) were women, with an average age of 59.1 years (32-79). SRS was applied as primary treatment in 83.7% (n=67) and in 16.3% (n=13) as an adjuvant treatment to surgery. SRS treatment was provided using LINAC (Varian 600, 6MeV) with M3 micromultilamines (brainLab) and stereotactic frame. The average tumor volume was 3.12cm3 (0.34-10.36cm3) and the coverage dose was 14Gy (12-16Gy). We performed a retrospective descriptive analysis and survival analysis was performed with the Kaplan-Meier method and multivariate analysis to determine those factors predictive of tumor progression or clinical improvement. RESULTS: After an average follow-up period of 86.9 months (12-184), the tumor control rate was 92.8% (n=77). At the end of the study, there was an overall reduction in tumor volume of 32.8%, with an average final volume of 2.11cm3 (0-10.35cm3). The progression-free survival rate at 5, 10 and 12 years was 98%, 95% and 83.3% respectively. The higher tumor volume (p=0.047) was associated with progression. There was clinical improvement in 26.5% (n=21) of cases and clinical worsening in 16.2% (n=13). Worsening is related to the radiation dose received by the brainstem (p=0.02). Complications were 8.7% (7 cases) of hearing loss, 5% (4 cases) of brain radionecrosis, and 3.7% (3 cases) of cranial nerve V neuropathy. Hearing loss was related to initial tumor size (p=0.033) and maximum dose (p=0.037). The occurrence of radionecrosis with the maximum dose (p=0.037). CONCLUSIONS: Treatment of cerebellopontine angle meningiomas with single-dose SRS using LINAC is effective in the long term. Better tumor control rates were obtained in patients with small lesions.

Radiocirugía estereotáxica por gamma knife en un paciente con cavernoma cerebral y síndrome de Evans

El cavernoma cerebral es una malformación vascular de diagnóstico infrecuente. Se define como una malformación a nivel de la vasculatura microcerebral que, dependiendo a la ubicación y si existe la posibilidad de ruptura, conlleva a una emergencia que puede terminar en la muerte del paciente. En esta oportunidad se reporta el caso de un paciente con cavernoma cerebral asociado al síndrome de Evans. Se decide manejo quirúrgico de la lesión por aumento de intensidad de cefalea e intolerancia oral. Dada la coexistencia del Síndrome de Evans y la alta tasa de morbimortalidad es que se decide manejo quirúrgico mediante radiocirugía estereotáxica con gamma knife. El uso de dosis de margen bajo para tratamiento con gamma knife para uso en cavernomas cerebrales produce un manejo controlado para sintomatología de convulsiones y mejor expectativa de calidad de vida.

Cerebral cavernoma is an infrequently diagnosed vascular malformation. It is defined as a malformation at the level of the microcerebral vasculature that, depending on the location and if there is a possibility of rupture, leads to an emergency that can end in the death of the patient. On this occasion, we report a case of a patient with cerebral cavernoma associated with Evans syndrome. Surgical management of the lesion was decided due to increased intensity of headache and oral intolerance. Given the coexistence of Evans Syndrome and the high rate of morbidity and mortality, surgical management was decided by stereotaxic radiosurgery with a gamma knife. The use of low-margin doses for treatment with gamma knife for use in brain cavernomas produces controlled management for seizure symptoms and better quality of life expectancy.

Gamma Knife® stereotactic radiosurgery as a treatment for essential and parkinsonian tremor: long-term experience.

INTRODUCTION: Unilateral Gamma Knife™ stereotactic radiosurgery on the ventral-intermediate nucleus of the thalamus is a minimally invasive neurosurgical option for refractory tremor. We describe the experience of Gamma Knife™ thalamotomy (GKT) in patients with essential tremor (ET) and tremor-dominant Parkinson's disease (PD) at our specialised stereotactic neurosurgery unit. METHODS: We reviewed the cases of patients treated with GKT between January 2014 and February 2018 with a minimum of 12 months' follow-up. We analysed clinical and demographic variables, indication, radiation dose, effectiveness (based on subscales of the Fahn-Tolosa-Marin [FTM] scale and the Movement Disorders Society-Unified Parkinson's Disease Rating Scale [MDS-UPDRS] motor score), and adverse events. RESULTS: Thirteen patients were registered, 6 with a diagnosis of tremor-dominant PD, four with refractory ET, and three with ET and PD. Median age was 78 years (range, 62-83), with seven patients aged over 75 years. Four patients were receiving anticoagulants and two had history of stroke. The maximum radiation dose administered was 130 Gy. Mean (standard deviation) follow-up duration was 30.0 (14.5) months. Significant tremor improvement was observed on the FTM subscales: 63.6% at 12 months and 63.5% at the end of follow-up; MDS-UPDRS tremor items showed improvements of 71.3% at 12 months and 60.3% at the end of follow up. Eleven patients reported significant improvements in quality of life, and 3 reported mild and transient adverse effects. CONCLUSIONS: This is the largest series of patients with essential and parkinsonian tremor treated with GKT and followed up in the long term in Spain. GKT can be safe and effective in the long term in patients with refractory tremor, including in elderly patients and those receiving anticoagulants.

CyberKnife Radiosurgery for refractory bilateral trigeminal neuralgia. Case report

Case description: A case of a 37-year-old female patient suffering from refractory bilateral trigeminal neuralgia is presented, who underwent various interventions such as acupuncture, block therapies and even microvascular decompression without effective pain relief. Clinical findings: Paresthesias and shooting-like twinges of pain intensity 10/10 in bilateral maxillary and mandibular branches of the trigeminal nerve, with nasal and intraoral triggers that made eating impossible, becoming increasingly severe since refractoriness to microvascular decompression and carbamazepines, triggering the twinges even during sleep, generating somnolence, depressive mood and social isolation. Treatment and results: The patient was evaluated by an interdisciplinary neuro-oncology team, where, in accordance with the analysis of the brain magnetic resonance imaging and the patient's history, it was indicated to perform Cyberknife® radiosurgery in monofraction on the left trigeminal and subsequently treat the contralateral trigeminal. When treated with Cyberknife® radiosurgery, the patient reported absolute improvement in her pain for 2 years. Clinical relevance: Radiosurgery by CyberKnife is not yet the first line of management in trigeminal neuralgia, however, it should be considered since several studies have managed to demonstrate an increase in the quality of life of patients and pain relief in refractory or severe cases. of said pathology.

Descripción del caso: Se presenta un caso de paciente femenino de 37 años que padecía neuralgia del trigémino bilateral refractaria, tratada con terapias alternativas, cirugía de descompresión microvascular, analgesia multimodal y terapias de bloqueo sin alivio efectivo del dolor. Hallazgos clínicos: Parestesias y punzadas tipo disparo de intensidad del dolor 10/10 en ramas maxilar y mandibular bilaterales del nervio trigémino, con gatillos nasales e intraorales que imposibilitaban comer, tornándose cada vez más severa desde refractariedad a descompresión microvascular y carbamazepinas, desencadenándose las punzadas incluso en el sueño, provocando somnolencia, animo depresivo y aislamiento social. Tratamiento y resultados: La paciente fue sometida a valoración por equipo interdisciplinario de neurooncología, donde en concordancia con el análisis de la resonancia magnética cerebral y los antecedentes de la paciente, se indicó realización de radiocirugía por Cyberknife en monofracción sobre trigémino izquierdo y posteriormente tratar el contralateral. Al ser tratada con radiocirugía Cyberknife® la paciente refiere mejora absoluta de su dolor desde hace 2 años. Relevancia clínica: La Radiocirugía por Cyberknife aún no es primera línea de manejo en neuralgia del trigémino, sin embargo, debería considerarse ya que diversos estudios han logrado demostrar un aumento en la calidad de vida de los pacientes y alivio del dolor en casos refractarios o graves de dicha patología.

Risk of symptomatic radiation necrosis in patients treated with stereotactic radiosurgery for brain metastases.

INTRODUCTIO: Stereotactic radiosurgery (SRS) is a treatment option in the initial management of patients with brain metastases. While its efficacy has been demonstrated in several prior studies, treatment-related complications, particularly symptomatic radiation necrosis (RN), remains as an obstacle for wider implementation of this treatment modality. We thus examined risk factors associated with the development of symptomatic RN in patients treated with SRS for brain metastases. PATIENTS AND METHODS: We performed a retrospective review of our institutional database to identify patients with brain metastases treated with SRS. Diagnosis of symptomatic RN was determined by appearance on serial MRIs, MR spectroscopy, requirement of therapy, and the development of new neurological complaints without evidence of disease progression. RESULTS: We identified 323 brain metastases treated with SRS in 170 patients from 2009 to 2018. Thirteen patients (4%) experienced symptomatic RN after treatment of 23 (7%) lesions. After SRS, the median time to symptomatic RN was 8.3 months. Patients with symptomatic RN had a larger mean target volume (p<0.0001), and thus larger V100% (p<0.0001), V50% (p<0.0001), V12Gy (p<0.0001), and V10Gy (p=0.0002), compared to the rest of the cohort. Single-fraction treatment (p=0.0025) and diabetes (p=0.019) were also significantly associated with symptomatic RN. CONCLUSION: SRS is an effective treatment option for patients with brain metastases; however, a subset of patients may develop symptomatic RN. We found that patients with larger tumor size, larger plan V100%, V50%, V12Gy, or V10Gy, who received single-fraction SRS, or who had diabetes were all at higher risk of symptomatic RN.

Comprehensive quality assurance for intracranial radiosurgery treatments using a postal system / Garantía de calidad para tratamientos de radiocirugía intracranial usando un sistema postal

Radiosurgery is a high-precision technique for delivering, in most cases, a single highly conformal dose to a stereotactically localized target. It can be indicated for small intracranial injury treatment, using either multiple sources of 60Co (γ rays) or high energy photon beams produced by linear accelerators. In order to minimize the impact of inaccurate localization of the target or dose delivery, a rigorous Quality Assurance (QA) program must be enforced, which should include an independent auditing system. This work proposes a simple and reliable postal QA phantom to be used as an independent evaluation. In it two important parameters were verified such as, the dosimetric precision of the planning system, by comparing the absorbed doses measured in the target volume using different dosimeters (ionization chamber, films, thermoluminescent dosimeters and L-alanine dosimeters) all calibrated against a small volume ion chamber. The exact positioning of the target volume was localized using air spaces and small steel spheres to find the appropriate target coordinates. The head phantom and the instruction sheets were extensively tested and sent by mail to selected institutions. The overall results were very encouraging and suggest that the proposed phantom may be used as a postal system as part of an independent QA tool in radiosurgery.

La radiocirugía es una técnica de alta precisión para administrar, en la mayoría de los casos, una sola dosis altamente conformada en un objetivo localizado estereotípicamente. Puede estar indicado para el tratamiento de pequeñas lesiones intracraneales, utilizando múltiples fuentes de 60Co (rayos γ) o haces de fotones de alta energía producidos por aceleradores lineales. Con el fin de minimizar el impacto de la ubicación inexacta de la administración de la meta o de la dosis, se debe aplicar un riguroso programa de control de calidad (QA), que debe incluir un sistema de auditoría independiente. Este documento propone un fantoma postal de control de calidad simple y fiable que se utilizará como evaluación independiente. Se verificó dos parámetros importantes, como la precisión dosimétrica del sistema de planificación, comparando las dosis absorbidas medidas en el volumen objetivo mediante diferentes dosis (cámara de ionización, películas, dosímetros Termoluminiscentes y dosímetros de L-alanina) todos calibrados con una pequeña cámara de iones de volumen. El posicionamiento exacto del volumen objetivo se localizó utilizando espacios aéreos y pequeñas esferas de acero para encontrar las coordenadas de destino adecuadas. El fantoma principal y las hojas de instrucciones fueron ampliamente probados y enviados por correo a instituciones seleccionadas. Los resultados generales fueron muy alentadores y sugieren que el fantoma propuesto puede utilizarse como sistema postal como parte de una herramienta independiente de control de calidad en radiocirugía.

Volumetric modulated arc radiosurgery for brain metastases from breast cancer: A single-center study / Radiocirugía con arcoterapia volumétrica modulada para el tratamiento de metástasis cerebrales de cáncer de mama: Un estudio monocéntrico

Abstract Background: Whole-brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS) are two treatment modalities commonly utilized to treat brain metastases (BMs). Aim: The purpose of this study is to analyse retrospectively the local control and survival of patients with BMs of breast cancer (BC) treated via radiosurgery using Volumetric Modulated Arc Therapy (VMAT-RS). Methods: 18 patients with 41 BMs of BC and treated by VMAT-RS were studied. They were classified according to the molecular subtype of BC and the modified breast graded prognostic assessment -GPA- index. Patients presented 1-4 BMs, which were treated with 5 non-coplanar VMAT arcs. The spatial distribution of BMs, the influence of receptor status on the location of the lesions and survival assessed via the Kaplan-Meier model were analyzed. Results: The median survival time (MST) was 19.7 months. Statistically significant differences were determined in the MST according to the Karnofsky performance status (p= 0.02) and the HER2 status (p= 0.004), being more prolonged in the HER2+ patients. Finally, our results showed that the cerebellum is the predominant site of breast cancer BMs, and also suggested that HER2+BMs had a predilection for some structures of the posterior circulation, such as the cerebellum, brainstem and occipital lobes (p= 0.048). Conclusions: The VMAT-RS is a technique with an overall survival comparable to other radiosurgery techniques. The baseline situation at the time of treatment, the modified breast-GPA and the molecular subtypes, are factors that significantly influence patient survival.

Resumen Antecedentes: La radioterapia holocraneal (WBRT) y la radiocirugía estereotáctica (SRS) son dos modalidades de tratamiento comúnmente empleados para el tratamiento de las metástasis cerebrales (BMs). Objetivo: El propósito de este estudio es analizar de forma retrospectiva el control local y la supervivencia de los pacientes con BMs de cáncer de mama (BC) tratados mediante radiocirugía empleando arcoterapia volumétrica modulada (VMAT-RS). Métodos: Se analizaron 18 pacientes con 41 BMs de BC tratados mediante VMAT-RS. Se clasificaron según el subtipo molecular de BC y el GPA (Graded Prognostic Assessment) modificado de cáncer de mama. Los pacientes presentaron de 1-4 BMs, las cuales fueron tratadas con 5 arcos VMAT no coplanares. Se analizó la distribución espacial de las BMs, la influencia del status del receptor en la localización de las lesiones y la supervivencia evaluada mediante el modelo de Kaplan-Meier. Resultados: La mediana del tiempo de supervivencia (MST) fue de 19.7 meses. Se hallaron diferencias estadísticamente significativas en el MST según el índice de Karnofsky (p= 0.02) y el status de HER2 (p= 0.004), siendo más prolongado en las pacientes HER2+. Por último, nuestros resultados mostraron que el cerebelo es el lugar predominante de las BMs de cáncer de mama, y también sugirieron que las BMs HER2+ presentaban una predilección por algunas estructuras de la circulación posterior, como el cerebelo, el tronco cerebral y los lóbulos occipitales (p= 0.048). Conclusiones: VMAT-RS es una técnica con una supervivencia global comparable a otras técnicas de radiocirugía. La situación basal en el momento del tratamiento, el GPA modificado de cáncer de mama así como los subtipos moleculares de cáncer de mama, son factores que influyen de forma significativa en la supervivencia de los pacientes.

Manejo actual de las metástasis vertebrales: un trabajo en equipo / Current management of vertebral metastases: teamwork

La enfermedad metastásica vertebral es frecuente en los pacientes con cáncer avanzado, y conlleva a complicaciones inherentes a su progresión, como lo son la fractura patológica vertebral y la compresión neural metastásica. Se realizó una revisión de los aspectos terapéuticos actuales del manejo de la progresión y de las complicaciones de la enfermedad metastásica vertebral, enfatizando su enfrentamiento sistémico y personalizado. Nuestro objetivo principal es proporcionar información sobre el tratamiento actual de esta afección y la utilidad del manejo sistémico y multidisciplinario.

Metastatic spinal disease is common in patients with advanced cancer, and leads to complications inherent in its progression, such as pathological vertebral fracture and metastatic neural compression. A review of the current therapeutic aspects regarding the progression and complications of metastatic spinal disease was performed, highlighting its systemic, personalized approach. Our aim is to provide information about the current treatment of this condition and the usefulness of its systemic and multidisciplinary management.

Primera Radiocirugía de schwannoma vestibular en el sistema público uruguayo, Hospital Regional de Tacuarembó. Centro Oncológico del Norte

Resumen: Los schwannomas vestibulares son tumores benignos de lento crecimiento. Aproximadamente el 90% son de presentación unilateral, el 10% restante, son bilaterales y se encuentran asociados al síndrome de Neurofibromatosis tipo 2. Las opciones de tratamiento son observación, cirugía o radiocirugía. La radiocirugía es un tratamiento seguro, con altas tasas de control local y baja morbilidad en schwannomas vestibulares menores a 3 cm de diámetro mayor. Reportamos la primera radiocirugía realizada en el sistema público uruguayo para este tipo de patologías.

Abstract: Vestibular schwannomas are slow-growing benign tumors. Approximately 90% are unilateral, the remaining 10% are bilateral and are associated with Neurofibromatosis type 2 syndrome. Treatment options are observation, surgery or radiosurgery. Radiosurgery is a safe treatment, with high local control rates and low morbidity in vestibular schwannomas smaller than 3 cm in major diameter. We report the first radiosurgery performed in the Uruguayan public system for this type of pathology.

Resumo: Os schwannomas vestibulares são tumores benignos de crescimento lento. Aproximadamente 90% são unilaterais, os restantes 10% são bilaterais e estão associados à síndrome de neurofibromatose tipo 2. As opções de tratamento são observação, cirurgia ou radiocirurgia. A radiocirurgia é um tratamento seguro, com altas taxas de controle local e baixa morbilidade em schwannomas vestibulares com menos de 3 cm de diâmetro maior. Relatamos a primeira radiocirurgia realizada no sistema público uruguaio pra este tipo de patologia.

Tratamiento con CyberKnife®: descripción de la respuesta y los efectos adversos en las metástasis cerebrales / Description of brain metastasis response and adverse effects to CyberKnife® treatment

RESUMEN Introducción: la primera causa de muerte por cáncer son las metástasis. La supervivencia media, para pacientes no tratados, es máximo de tres meses, que pueden extenderse de seis a doce con radioterapia y quimioterapia, dependiendo del tumor. La radiocirugía estereotáctica dirige la radiación ionizante a una metástasis guiada por tomografía computarizada o resonancia magnética, reduciendo así la radiación en el tejido normal y los efectos adversos. Su principal objetivo es lograr el control tumoral en los pacientes con oligometástasis. Métodos: estudio observacional, retrospectivo, con fuente mixta; se describen los resultados del tratamiento con CyberKnife® en metástasis cerebrales. Resultados: se evaluaron 31 pacientes con 62 metástasis, la edad media fue de 54 años y 74,2 % fueron mujeres. El cáncer de pulmón fue el origen más frecuente (54,8 %), La mitad de los casos tenía más de dos metástasis. La ubicación más común fue en los lóbulos frontales (33,9 %), siendo necróticas el 48,4 % de las lesiones. Hubo tratamiento previo en el 69,4 % de los tumores. Hubo radionecrosis en el 19,4 % de las lesiones, edema vasogénico en 77,4 % de ellas y recaída en 59,7 %. Se redujo el tamaño del tumor en el 80,7 % de las lesiones y se alcanzó el control tumoral en el 83,9 % de estas. Conclusión: el tratamiento con CyberKnife® logró el control en, por lo menos, cuatro quintas partes de las lesiones, con influencia de la ubicación de las metástasis en el sistema nervioso central y una aceptable prevalencia de la radionecrosis como complicación.

SUMMARY Background: Cancer ́s first cause of death are metastases. Mean survival for untreated patients is 3 months, which can extend to six or twelve months with conventional radiotherapy or chemotherapy, depending on the tumor. Stereotactic radiosurgery is a method which aims an ionizing radiation dose towards an intracranial target, guided by computarized tomography or magnetic resonance, reducing radiation on healthy brain tissue, as well as adverse effects. Its main indication is to achieve tumor control in patients with oligometastases. Methods: Retrospective, observational study, with primary and secondary sources for data, for describing results of CyberKnife® treatment. Results: Data were available for 31 patients and 62 metastases. Mean age was 54 years, 74,19% were women. Lung cancer was the most frequent primary tumor (54,8%); half of the cases had more than two metastases; most common location was frontal lobes (33,9%), being 48,4% of the tumors morphologically necrotic. There was a previous treatment in 69,4% of the tumors. There was radionecrosis in 19,4% of the metastases, vasogenic edema in 77,4% of them and relapses in 59,7% of the tumors. Tumor size was reduced in 80,7% of the metastases and tumor control was achieved in 83,9% of them. Conclusions: CyberKnife® was able to achieve control in at least four fifths of the treated metastases, with a relevant influence of metastases ́ location in central nervous and an acceptable prevalence of radionecrosis as a complication.

Comparación dosimétrica en radiocirugía intracraneal entre Cyberknife y un bisturí de rayos gamma y su puesta en marcha Centroamérica / Dosimetric comparison in intracranial radiosurgery between Cyberknife and a gamma knife and its implementation Central America

Introducción: La dupla Cyberknife y bisturí de rayos gamma (Infini) que se describe es la primera en Latinoamérica. Ambas máquinas han mostrado ser los mejores equipos para radiocirugía intracraneal. Se describe la experiencia inicial de Cyberknife en Centroamérica y su incorporación a un programa existente de bisturí de rayos gamma por vía de análisis comparativos dosimétricos. Material y método: En el año 2019 se realizaron planes comparativos y se trataron 180 pacientes con radiocirugía intracraneal con ambos sistemas tanto en patología tumoral, como vascular y funcional. Resultados: En el análisis dosimétrico comparativo en el gradiente de dosis de Infini mostró ser superior a Cyberknife en todos los casos. Para una esfera utilizando el colimador de 4 mm en Infini y de 5 mm en Cyberknife utilizando un plan isocéntrico con el -Trigeminal Path- el gradiente de dosis para Infini fue de 1.5 y para Cyberknife de 1.66. Para los casos de patología el gradiente de dosis media para Infini fue de 3 mm y para Cyberknife de 3.8 mm. Dando un puntaje de gradiente de dosis (Gradient Score Index) si Infini fuese de 100, Cyberknife obtuvo 87.3. Cyberknife mostró mejor conformalidad y cobertura (97% versus 96%) para todos los targets. Entre enero 2019 y enero 2020 se realizaron 180 radiocirugías, 60 con Cyberknife y 120 con Infini, 60 pacientes recibieron 146 sesiones con Cyberknife, radiocirugía fraccionada 39 (65%) y 21 (35%) en sesión única. Las dosis medias en tumores en dosis única fue 15 Gy (12.5 a 25 Gy) y en radiocirugía fraccionada 21 Gy (18 y 35). Ningún paciente ha experimentado toxicidad mayor a grado dos. Conclusiones: El bisturí de rayos gamma rotatorio reveló superioridad en gradiente de dosis con relación al Cyberknife. En su primer año Cyberknife ha mostrado ser una herramienta segura en el tratamiento de patología intracraneal. Más seguimiento clínico y radiológico es necesario para verificar su efectividad comparativa

Introduction: The match between Cyberknife and Infini here described in this article is the first in Latinamerica. Both machines have proven to be the best for intracranial radiosurgery, we describe our initial experience with Cyberknife in Central America and how it was incorporated in an existing gamma ray program by ways of dosimetry comparisons. Methods: During 2019 comparative plans were made and a total of 180 patients received intracranial radiosurgery with both technologies, patients were treated for tumors, vascular anomalies, and functional pathology. Results: Basic dosimetry analysis regarding dose gradient the Infini proved superior to Cyberknife in all plans. For a sphere using the 4 mm collimator in Infini and the 5 mm in Cyberknife along with an isocentric plan using the -Trigeminal Path- dose gradient was 1.5 for Infini and 1.66 for Cyberknife. For the pathology cases Infini was 3 mm and for Cyberknife 3.8 mm on mean. Giving a Gradient Score Index (GSI) if Infini would be 100, Cyberknife would be 87.3. Cyberknife showed better conformality and coverage for all pathology targets (97% versus 96%). From January 2019 to January 2020, 180 intracranial radiosurgeries were done, 60 with Cyberknife and 120 with Infini, 60 patients received 146 sessions with Cyberknife, fractionated scheme 39 (65%) and 21 (35%) single dose. The median dose for tumors was 15 Gy (12.5 a 25 Gy) for single session and 21 Gy (18 y 35) for fractionated scheme. No patient experienced a higher toxicity tan grade two. Conclusions: In its first year Cyberknife has shown to be safe in treating intracranial pathology. Infini had a better dose gradient than Cyberknife. Longer clinical and radiological follow-up is needed to verify its comparative effectiveness.

Enfermedad metastásica de la columna vertebral / Metastatic spine disease

Siendo el cáncer la segunda causa de muerte en el mundo, las metástasis óseas son su tercera localización más frecuente, junto con la columna vertebral, ocupando el 65% de ellas. Lo anterior, sumado a una población envejeciendo y un abismante progreso en los tratamientos de quimio, radio y hormonoterapia, junto con técnicas quirúrgicas cada vez menos invasivas exige abordar este tema. Se realiza una revisión narrativa, con la literatura actual y consensos internacionales en el área, describiendo los factores que generan las metástasis vertebrales, sus síntomas de alarma (dolor y compromiso neurológico), métodos de estudio y diagnóstico (Rx, TAC, RMN, cintigrama óseo, Pet CT, biopsia) y método de clasificación de la compresión medular. Además, se revisan diferentes tipos de puntuación para la toma de decisión quirúrgica y se exponen las técnicas más modernas de tratamiento combinado de cirugía separación más radioterapia esterotáctica que ofrecen menor invasión al paciente con mejores resultados de control local de la enfermedad.

Being cancer the second cause of death in the world, bone metastases are its third most frequent location, along with the spine, occupying 65% of them. The aforementioned, added to an aging population and an abysmal progress in the treatments of Chemo, Radio and Hormone therapy, together with increasingly less invasive surgical techniques requires addressing this issue. A narrative review is carried out, with current literature and international consensus in the area, describing the factors that generate vertebral metastases, their alarm symptoms (pain and neurological compromise), study and diagnostic methods (Rx, CT Scan, MRI, Bone Scan, PET CT, needle Biopsy) and method of classification of spinal compression. In addition, different types of punctuation for surgical decision making are revised and the newer combine treatment with less invasive surgery plus Sterotactic High dose radiation is presented as the todaýs gold standard for the best local control for the Metastatic Spine Disease.

Risk of symptomatic radiation necrosis in patients treated with stereotactic radiosurgery for brain metastases.

INTRODUCTIO: Stereotactic radiosurgery (SRS) is a treatment option in the initial management of patients with brain metastases. While its efficacy has been demonstrated in several prior studies, treatment-related complications, particularly symptomatic radiation necrosis (RN), remains as an obstacle for wider implementation of this treatment modality. We thus examined risk factors associated with the development of symptomatic RN in patients treated with SRS for brain metastases. PATIENTS AND METHODS: We performed a retrospective review of our institutional database to identify patients with brain metastases treated with SRS. Diagnosis of symptomatic RN was determined by appearance on serial MRIs, MR spectroscopy, requirement of therapy, and the development of new neurological complaints without evidence of disease progression. RESULTS: We identified 323 brain metastases treated with SRS in 170 patients from 2009 to 2018. Thirteen patients (4%) experienced symptomatic RN after treatment of 23 (7%) lesions. After SRS, the median time to symptomatic RN was 8.3 months. Patients with symptomatic RN had a larger mean target volume (p<0.0001), and thus larger V100% (p<0.0001), V50% (p<0.0001), V12Gy (p<0.0001), and V10Gy (p=0.0002), compared to the rest of the cohort. Single-fraction treatment (p=0.0025) and diabetes (p=0.019) were also significantly associated with symptomatic RN. CONCLUSION: SRS is an effective treatment option for patients with brain metastases; however, a subset of patients may develop symptomatic RN. We found that patients with larger tumor size, larger plan V100%, V50%, V12Gy, or V10Gy, who received single-fraction SRS, or who had diabetes were all at higher risk of symptomatic RN.

Different radioinducid tumors synchrony in an acute lymphoblastic leukemia survivor. / Sincronía de diferentes tumores radioinducidos en superviviente de leucemia linfoblástica aguda.

The cranial radiation-induced tumors appearance in pediatric patients treated for hematological diseases such as leukemia/T-lymphoblastic lymphoma (T-ALL/LBL) is a known phenomenon that may include lesions of different malignant degrees and require neurosurgical treatment. We present the case of a 38-year-old man referred to our department for a sudden diplopia with 6-month progressive left hemiparesis and frequent falls. After imaging tests, different intra and extraxial lesions with different radiological behavior were observed, performing a single surgical approach for their resection. The pathological anatomy confirms four histological variants: meningioma (grade 1 and 2 [atypical]), subependymoma, and cavernoma. We discuss the teratogenic role of ionizing radiation.

Gamma Knife® stereotactic radiosurgery as a treatment for essential and parkinsonian tremor: long-term experience. / Radiocirugía estereotáctica con Gamma Knife® como tratamiento del temblor esencial y parkinsoniano: experiencia a largo plazo.

INTRODUCTION: Unilateral Gamma Knife™ stereotactic radiosurgery on the ventral-intermediate nucleus of the thalamus is a minimally invasive neurosurgical option for refractory tremor. We describe the experience of Gamma Knife™ thalamotomy (GKT) in patients with essential tremor (ET) and tremor-dominant Parkinson's disease (PD) at our specialised stereotactic neurosurgery unit. METHODS: We reviewed the cases of patients treated with GKT between January 2014 and February 2018 with a minimum of 12 months' follow-up. We analysed clinical and demographic variables, indication, radiation dose, effectiveness (based on subscales of the Fahn-Tolosa-Marin [FTM] scale and the Movement Disorders Society-Unified Parkinson's Disease Rating Scale [MDS-UPDRS] motor score), and adverse events. RESULTS: Thirteen patients were registered, 6 with a diagnosis of tremor-dominant PD, four with refractory ET, and three with ET and PD. Median age was 78 years (range, 62-83), with seven patients aged over 75 years. Four patients were receiving anticoagulants and two had history of stroke. The maximum radiation dose administered was 130 Gy. Mean (standard deviation) follow-up duration was 30.0 (14.5) months. Significant tremor improvement was observed on the FTM subscales: 63.6% at 12 months and 63.5% at the end of follow-up; MDS-UPDRS tremor items showed improvements of 71.3% at 12 months and 60.3% at the end of follow up. Eleven patients reported significant improvements in quality of life, and 3 reported mild and transient adverse effects. CONCLUSIONS: This is the largest series of patients with essential and parkinsonian tremor treated with GKT and followed up in the long term in Spain. GKT can be safe and effective in the long term in patients with refractory tremor, including in elderly patients and those receiving anticoagulants.