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Purpose. To evaluate the feasibility of use of an 1.5 T magnetic resonance (MR)-linear accelerator MR-linac for imaging in gynaecologic high-dose-rate (HDR) brachytherapy.Method. Commissioning measurements for MR images quality control, geometric distortion, dwell position accuracy, applicator reconstruction and end-to-end test for a tandem-and-ring applicator were performed following the recommendations of American Brachytherapy Society, International Commission on Radiation Units and Measurements and Report of the Brachytherapy Working Group of the Spanish Society of Medical Physics. The values for MR-based IGABT were compared to the corresponding values with computed tomography (CT).Results. Measured distorsions for the MR images were less than 0.50 mm compared to the CT images. The differences between 3D displacements for all dwell positions were 0.66 mm and 0.62 mm for the tandem and ring, respectively. The maximum difference is 0.64 mm for the distances from the applicator tip obtained using the films. The CT and MR dose differences for the right and left 'A' points were 0.9% and -0.7%, respectively. Similar results were observed in terms of dose distribution for CT and Mr The gamma passing rate was 99.3% and 99.5%, respectively.Conclusion. The use of MR images from an MR-linac used in a radiotherapy service for gynaecological brachytherapy was proved to be feasible, safe and precise as the geometrical differences were less than 1 mm, and the dosimetric differences were less than 1% when comparing to the use of CT images for the same purpose.
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Braquiterapia , Imagen por Resonancia Magnética , Dosificación Radioterapéutica , Radioterapia Guiada por Imagen , Tomografía Computarizada por Rayos X , Braquiterapia/métodos , Humanos , Femenino , Imagen por Resonancia Magnética/métodos , Tomografía Computarizada por Rayos X/métodos , Radioterapia Guiada por Imagen/métodos , Aceleradores de Partículas , Neoplasias de los Genitales Femeninos/radioterapia , Neoplasias de los Genitales Femeninos/diagnóstico por imagen , Planificación de la Radioterapia Asistida por Computador/métodos , Fantasmas de Imagen , Estudios de FactibilidadRESUMEN
OBJECTIVE: This study aimed to assess the efficacy and tolerability of stereotactic body radiation therapy (SBRT) for the treatment of liver metastases. METHODS: Patients with up to 5 liver metastases were enrolled in this prospective multicenter study and underwent SBRT. Efficacy outcomes included in-field local control (LC), progression-free survival (PFS), and overall survival (OS). Acute and late toxicities were evaluated using CTCAE v.4.0. RESULTS: A total of 52 patients with 105 liver metastases were treated between 2015 and 2018. The most common primary tumor was colorectal cancer (72% of cases). Liver metastases were synchronous with the primary tumor diagnosis in 24 patients (46.2%), and 21 patients (40.4%) presented with other extrahepatic oligometastases. All patients underwent intensity-modulated radiation therapy (IMRT)/volumetric-modulated arc therapy (VMAT) with image-guided radiation therapy (IGRT) and respiratory gating, and a minimum biologically effective dose (BED10Gy) of 100 Gy was delivered to all lesions. With a median follow-up of 23.1 months (range: 13.4-30.9 months) since liver SBRT, the median actuarial local progression-free survival (local-PFS) was not reached. The actuarial in-field LC rates were 84.9% and 78.4% at 24 and 48 months, respectively. The median actuarial liver-PFS and distant-PFS were 11 and 10.8 months, respectively. The actuarial median overall survival (OS) was 27.7 months from SBRT and 52.5 months from metastases diagnosis. Patients with lesion diameter ≤ 5 cm had significantly better median liver-PFS (p = 0.006) and OS (p = 0.018). No acute or late toxicities of grade ≥ 3 were observed. CONCLUSIONS: This prospective multicenter study confirms that liver SBRT is an effective alternative for the treatment of liver metastases, demonstrating high rates of local control and survival while maintaining a low toxicity profile.
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Neoplasias Hepáticas , Radiocirugia , Radioterapia de Intensidad Modulada , Humanos , Radiocirugia/métodos , Radiocirugia/efectos adversos , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/radioterapia , Neoplasias Hepáticas/mortalidad , Masculino , Estudios Prospectivos , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Adulto , Radioterapia de Intensidad Modulada/métodos , Supervivencia sin Progresión , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/radioterapia , Neoplasias Colorrectales/mortalidad , Radioterapia Guiada por Imagen , Tasa de SupervivenciaRESUMEN
INTRODUCTION: To guarantee treatment reproducibility and stability, immobilization devices are essential. Additionally, surface-guided radiation therapy (SGRT) serves as an accurate complement to frameless stereotactic radiosurgery (SRS) and stereotactic radiotherapy (SRT) by aiding patient positioning and real-time monitoring, especially when non-coplanar fields are in use. At our institute, we have developed a surface-guided SRS (SG-SRS) workflow that incorporates our innovative open-face mask (OM) and mouth bite (MB) to guarantee a precise and accurate dose delivery. METHODS: This study included 40 patients, and all patients were divided into closed mask (CM) and open-face mask (OM) groups according to different positioning flow. Cone beam computed tomography (CBCT) scans were performed, and the registration results were recorded before and after the treatment. Then Bland-Altman method was used to analyze the consistency of AlignRT-guided positioning errors and CBCT scanning results in the OM group. The error changes between 31 fractions in one patient were recorded to evaluate the feasibility of monitoring during treatment. RESULTS: The median of translation error between stages of the AlignRT positioning process was (0.03-0.07) cm, and the median of rotation error was (0.20-0.40)°, which were significantly better than those of the Fraxion positioning process (0.09-0.11) cm and (0.60-0.75)°. The mean bias values between the AlignRT guided positioning errors and CBCT were 0.01 cm, - 0.07 cm, 0.03 cm, - 0.30°, - 0.08° and 0.00°. The 31 inter-fractional errors of a single patient monitored by SGRT were within 0.10 cm and 0.50°. CONCLUSIONS: The application of the SGRT with an innovative open-face mask and mouth bite device could achieve precision positioning accuracy and stability, and the accuracy of the AlignRT system exhibits excellent constancy with the CBCT gold standard. The non-coplanar radiation field monitoring can provide reliable support for motion management in fractional treatment.
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Neoplasias Encefálicas , Radiocirugia , Radioterapia Guiada por Imagen , Humanos , Radiocirugia/métodos , Posicionamiento del Paciente , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/cirugía , Reproducibilidad de los Resultados , Máscaras , Radioterapia Guiada por Imagen/métodos , Encéfalo , Tomografía Computarizada de Haz Cónico/métodos , Planificación de la Radioterapia Asistida por Computador/métodosRESUMEN
Las nuevas tecnologías para el tratamiento del cáncer con radiación ionizante tienen especial interés en mejorar la calidad de las imágenes para el posicionamiento adecuado del paciente con sistemas de radioterapia guiada por imagen IGRT. El sistema Halcyon cuenta con imágenes de tomografía computarizada de haz de cono CBCT. Estas imágenes podrían ser una opción para escenarios donde no se cuente con una Tomografía Computarizada CT o el equipo se encuentre en reparación o mantenimiento especialmente para escenarios de intensión paliativa. La diferencia en la distribución de dosis en imágenes CT y CBCT fue analizada en este estudio. Los resultados mostraron diferencias en las unidades Hounsfield UH, aunque no fueron estadísticamente significativas, el volumen irradiado mostro diferencias máximas de 3,92% que no supera el 4% permitido para tratamientos de intensión paliativa. En cuanto a las dosis dispersas al tejido sano la diferencia tampoco supera el 4%. Nuestro estudio mostro que las imágenes CBCT pueden ser una alternativa para el tratamiento de metástasis óseas, sin embargo, estas imágenes todavía no pueden remplazar las imágenes CT utilizadas para el cálculo de dosis en radioterapia
New technologies for the treatment of cancer with ionizing radiation are of particular interest in improving image quality for proper patient positioning with image-guided radiation therapy IGRT systems. IGRT image-guided radiation therapy systems. The Halcyon system features cone beam computed tomography CBCT imaging. These images could be an option for scenarios where a CT scan is not available or the equipment is under repair or maintenance especially for is under repair or maintenance, especially for palliative scenarios. The difference in the The difference in dose distribution in CT and CBCT images was analyzed in this study. The results showed differences in Hounsfield UH units, although not statistically significant, the irradiated volume showed maximum differences of 3.92%, which is the maximum difference of 3.92%. Differences of 3.92%, which does not exceed the 4% allowed for palliative treatments. As for the doses dispersed to healthy tissue the difference does not exceed the 4% allowed for palliative treatments. Our study showed that CBCT imaging can be an alternative for the treatment of metastases. an alternative for the treatment of bone metastases, however, these images cannot yet replace the CT images used for dose calculation. CT images used for dose calculation in radiotherapy
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Humanos , Neoplasias Óseas/radioterapia , Radioterapia Guiada por Imagen/métodos , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Tomografía Computarizada de Haz Cónico/métodosRESUMEN
Nanoparticles have proven to be biocompatible and suitable for many biomedical applications. Currently, hyperthermia cancer treatments based on Fe nanoparticle infusion excited by alternating magnetic fields are commonly used. In addition to this, MRI-based image-guided radiotherapy represents, nowadays, one of the most promising accurate radiotherapy modalities. Hence, assessing the feasibility of combining both techniques requires preliminary characterization of the corresponding dosimetry effects. The present work reports on a theoretical and numerical simulation feasibility study aimed at pointing out preliminary dosimetry issues. Spatial dose distributions incorporating magnetic nanoparticles in MRI-based image-guided radiotherapy have been obtained by Monte Carlo simulation approaches accounting for all relevant radiation interaction properties as well as charged particles coupling with strong external magnetic fields, which are representative of typical MRI-LINAC devices. Two main effects have been evidenced: local dose enhancement (up to 60% at local level) within the infused volume, and non-negligible changes in the dose distribution at the interfaces between different tissues, developing to over 70% for low-density anatomical cavities. Moreover, cellular uptakes up to 10% have been modeled by means of considering different Fe nanoparticle concentrations. A theoretical temperature-dependent model for the thermal enhancement ratio (TER) has been used to account for radiosensitization due to hyperthermia. The outcomes demonstrated the reliability of the Monte Carlo approach in accounting for strong magnetic fields and mass distributions from patient-specific anatomy CT scans to assess dose distributions in MRI-based image-guided radiotherapy combined with magnetic nanoparticles, while the hyperthermic radiosensitization provides further and synergic contributions.
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Hipertermia Inducida , Nanopartículas , Neoplasias , Radioterapia Guiada por Imagen , Humanos , Reproducibilidad de los Resultados , Radiometría/métodos , Imagen por Resonancia Magnética , Método de Montecarlo , Dosificación Radioterapéutica , Neoplasias/diagnóstico por imagen , Neoplasias/radioterapiaRESUMEN
PURPOSE: Analyse outcomes of stage-I inoperable endometrial cancer (EC) patients from seven European centres treated with 3D-image-guided brachytherapy (IGBT) alone. MATERIALS AND METHODS: From 2004 to 2018, 62 patients (41 stage-IA and 21 IB) were retrospectively studied, analysing anaesthetic procedure, applicator type, BT-planning imaging, clinical target volume (CTV), BT schedule, overall daily-dose equivalent to 2 Gy (EQD2(α/ß=4.5 or 3)) to the CTV(α/ß=4.5) and D2 cm3(α/ß=3) for organs at risk. Complications were evaluated using CTCAEv4 scores. The 2 and 5 year survival was calculated [cancer-specific survival (CSS), disease-free survival (DFS), local relapse-free survival (LRFS), loco-regional relapse-free survival (LRRFS) and distant metastasis-free survival (DMFS)]. Descriptive analysis and the Kaplan-Meier method were used for survival analysis. RESULTS: Mean follow-up: 32.8 months (SD 33.7). Spinal anaesthesia (38/62) followed by none (16/62) were the most common. Y-shaped Rotte applicators were used in 74% of patients. High-dose rate brachytherapy was administered in 89%. Median D90 to the CTV was 58.9 Gy (8.66-144 Gy). Eight patients presented relapse: four uterine, four nodal and four distant. The 2 and 5 year CSS was 93.3 and 80.5%, DFS 84.8 and 80.5%, LRFS was 93.1 and 88.7%, LRRFS was 91 and 91% and DMFS was 90.2 and 90.2%, respectively, CSS was better in stage-IA vs. IB (p = 0.043). Late vaginal and bladder G3-complication rates were 2.1%, respectively. CONCLUSION: Inoperable EC patients can be safely treated by BT with 2 and 5 year CSS of 93 and 80.5%, respectively, with even better results for IA cases. Prospective studies on 3D-IGBT are necessary to better analyse EC patient outcomes based on dose and treated volumes.
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Braquiterapia/métodos , Neoplasias Endometriales/radioterapia , Imagenología Tridimensional , Radioterapia Guiada por Imagen , Neoplasias Uterinas/radioterapia , Anciano , Anciano de 80 o más Años , Neoplasias Endometriales/patología , Femenino , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios RetrospectivosRESUMEN
Resumo Ponticulus Posticus (PP) significa "pequena ponte posterior" em latim. É definida como uma pequena ponte óssea anormal, que é gerada entre a parte posterior do processo articular superior do osso occipital e a porção posterolateral da margem superior do arco posterior do Atlas. A associação entre PP e algumas anomalias dentárias já foi demonstrada, sendo a impacção palatina de caninos superiores uma delas. Objetivos: o presente estudo avaliou os efeitos das variáveis gênero, idade e padrão vertical, comparado na frequência e tipo de PP (forma parcial ou completa) em uma amostra retrospectiva transversal de radiografias cefalométricas laterais de pacientes saudáveis, ortodonticamente não tratados. Materiais e métodos: a amostra incluiu radiografias laterais de 300 pacientes (n = 300) (124 homens e 176 mulheres) de uma clínica odontológica da cidade de Lages/SC. A presença de Ponticulus Posticus (parcial ou completa) foi avaliada, levando-se em consideração gênero, idade e padrão vertical. Após análise descritiva dos dados, os mesmos foram submetidos ao teste chi quadrado (α = 0,05). Resultados: a prevalência geral de Ponticulus Posticus foi de 11% (30 de 300) com as formas parcial e completa verificadas, respectivamente, em 6,3% (19 de 300) e 4,7% (11 de 300) da amostra. Não foram encontradas associações com gênero (p = 0,611) e idade (p = 0,761). O padrão vertical teve relevância significativa com a presença de PP (p = 0,007). Conclusão: há uma associação positiva entre o padrão vertical do tipo braquifacial com uma maior prevalência de Ponticulus Posticus em suas formas parcial e completa.(AU)
Abstract Ponticus Posticus (PP) means "small posterior bridge" in Latin. It is defined as an abnormal bony bridge, which is generated between a posterior part of the upper articular process of the occipital bone and the posterolateral portion of the upper margin of the posterior arch of the Atlas vertebra. Objectives: the present study evaluated the effects of the variables gender, age, and vertical pattern, compared on the frequency and type of PP (partial form or complete) in a retrospective transversal sample of lateral cephalograms of healthy orthodontically untreated patients. Materials and methods: the sample included lateral cephalograms of 300 patients (n = 300) (124 men and 176 women) from a dental clinic in the city of Lages/SC. The presence of Ponticus Posticus (partial and complete) was evaluated considering gender, age, and vertical pattern. After descriptive analysis of the data, they were submitted to the chi square test (α = 0.05). Results: the overall prevalence of Ponticus Posticus was 11% (30 of 300) with its partial and complete forms verified respectively in 6.3% (19 of 300) and 4.7% (11 of 300) of the sample. No associations were found with gender (p = 0.611) and age (p = 0.761). The vertical pattern had significant relevance with the presence of PP (p = 0.007). Conclusion: there is a positive association between the vertical brachyfacial pattern type with the highest prevalence of Ponticus Posticus in its partial and complete forms (AU)
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Humanos , Masculino , Femenino , Adolescente , Adulto , Ortodoncia , Atlas Cervical , Anomalías Dentarias , Radioterapia Guiada por ImagenRESUMEN
INTRODUCTION: Hypofractionated radiation therapy for breast cancer requires highly precise delivery through the use of image-guided radiotherapy (IGRT). Surface-guided radiation therapy (SGRT) is being increasingly used for patient positioning in breast radiotherapy. We aimed to assess the role of SGRT for verification of breast radiotherapy and the tumour bed. MATERIALS AND METHODS: Prospective study of 252 patients with early stage breast cancer. A total of 1170 determinations of daily positioning were performed. Breast surface positioning was determined with SGRT (AlignRT) and correlated with the surgical clips in the tumour bed, verified by IGRT (ExacTrac). RESULTS: SGRT improved surface matching by a mean of 5.3 points compared to conventional skin markers (98.0 vs. 92.7), a statistically significant difference (p < 0.01, Wilcoxon Test). For surface matching values > 95%, ≥ 3 clips coincided in 99.7% of the determinations and all markers coincided in 92.5%. For surface matching rates > 90%, the location of ≥ 3 clips coincided in 99.55% of determinations. CONCLUSIONS: SGRT improves patient positioning accuracy compared to skin markers. Optimal breast SGRT can accurately verify the localisation of the tumour bed, ensuring matching with ≥ 3 surgical clips. SGRT can eliminate unwanted radiation from IGRT verification systems.
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Neoplasias de la Mama/radioterapia , Posicionamiento del Paciente/métodos , Radioterapia Guiada por Imagen/métodos , Adulto , Anciano , Anciano de 80 o más Años , Mama/diagnóstico por imagen , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Neoplasias de la Mama/cirugía , Femenino , Marcadores Fiduciales , Humanos , Mastectomía Segmentaria , Persona de Mediana Edad , Tratamientos Conservadores del Órgano/métodos , Estudios Prospectivos , Hipofraccionamiento de la Dosis de Radiación , Estadísticas no Paramétricas , Instrumentos Quirúrgicos , Tomografía Computarizada por Rayos XRESUMEN
El tratamiento con radioterapia, consiste en irradiar de forma homogénea el tumor, evitando irradiar los órganos cercanos. El desarrollo de la tecnología en el campo de la medicina, ha permitido que se cumpla este principio, con buenos resultados de respuesta objetiva, que se traduce en el control de la enfermedad de los pacientes con cáncer. La Tomografía axial computarizada por emisión de positrones (PET-CT) consigue una mayor precisión en el delineado del volumen blanco o tumoral. El propósito de este estudio fue analizar la influencia del uso del PET-CT en el delineado de volúmenes a tratar en la planificación del tratamiento con radiaciones.Se diseñó un estudio piloto con dos pacientes preparados para radioterapia por neoplasias malignas, a los cuáles se les realizó un TAC simple y un PET-CT y observadores independientes realizaron la delimitación del tumor. Se examinó la consistencia entre los observadores y las mediciones en las imágenes.El uso del PET-CT favoreció la delimitación del volumen a irradiar lo que disminuye el riesgo para los órganos vecinos.
The treatment with radiotherapy consists on irradiating in a homogeneous way the tumor, avoiding to irradiate the near organs. The development of the technology in the field of the medicine, it has allowed that this principle is completed, with good results of objective answer what allows the control of the illness of the patients with cancer. The computerized axial tomography by positrons emission (PET-CT) it gets a bigger precision in the one delineated of the white volume or tumoral. The purpose of this study was to analyze the influence of the use of the PET-CT in the one delineated of volumes to try in the planning of the treatment with radiations.A study pilot was designed with two prepared patients for radiotherapy for malignant diseases, to those which they were carried out a simple TAC and a PET-CT and independent observers carried out the delimitation of the tumor. The consistency was examined between the observers and the mensuration in the images.The use of the PET-CT favors the delimitation of the volume to irradiate what diminishes the risk for the neighboring organs.
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Humanos , Masculino , Radioterapia/métodos , Radioterapia Guiada por Imagen/métodos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Oncología por Radiación/métodos , Neoplasias/radioterapia , Neoplasias/diagnóstico por imagenRESUMEN
PURPOSE: Conventional post-prostatectomy radiation therapy comprises 6.5-8 weeks of treatment, therefore, hypofractionated and shortened schemes arouse increasing interest. We describe our experience regarding feasibility and clinical outcome of a post-prostatectomy moderate hypofractionated image-guided radiotherapy schedule MATERIALS AND METHODS: From Oct 2015-Mar 2020, 113 patients, median age of 62 years-old (range 45-76) and prostate adenocarcinoma of low risk (30%), intermediate risk (49%) and high risk (21%) were included for adjuvant (34%) or salvage radiation therapy (66%) after radical prostatectomy (RP). All patients underwent radiotherapy with image-guided IMRT/VMAT to a total dose of 62.5 Gy in 2.5 Gy/fraction in 25 fractions. Sixteen patients (14%) received concomitant androgen deprivation therapy. RESULTS: With a median follow-up of 29 months (range 3-60 months) all patients but three are alive. Eleven patients (10%) developed exclusive biochemical relapse while 19 patients (17%) presented macroscopically visible relapse: prostatectomy bed in two patients (2%), pelvic lymph nodes in 13 patients (11.5%) and distant metastases in four patients (4%). The 3 years actuarial rates for OS, bFRS, and DMFS were 99.1, 91.1 and 91.2%, respectively. Acute and late tolerance was satisfactory. Maximal acute genitourinary (AGU) toxicity was G2 in 8% of patients; maximal acute gastrointestinal (AGI) toxicity was G2 in 3.5% of patients; maximal late genitourinary (LGU) toxicity was G3 in 1% of patients and maximal late gastrointestinal (LGI) toxicity was G2 in 2% of patients. There were no cases of severe acute or late toxicity. No relationship was found between acute or late GI/GU adverse effects and dosimetric parameters, age, presence of comorbidities or concomitant treatments. CONCLUSIONS: Hypofractionated radiotherapy (62.5 Gy in 25 2.5 Gy fractions) is feasible and well tolerated with low complication rates allowing for a moderate dose-escalation that offers encouraging clinical results for biochemical control and survival in patients with prostate cancer after radical prostatectomy.
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Prostatectomía , Neoplasias de la Próstata/radioterapia , Neoplasias de la Próstata/cirugía , Hipofraccionamiento de la Dosis de Radiación , Anciano , Instituciones Oncológicas , Terapia Combinada , Estudios de Factibilidad , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Radioterapia Guiada por Imagen , Estudios Retrospectivos , Centros de Atención Terciaria , Resultado del TratamientoRESUMEN
Introducción y objetivos: El tratamiento estándar para pacientes con cáncer cervical localmente avanzado (CCLA) se basa en radioterapia externa y quimioterapia concomitante seguida de braquiterapia adaptativa guiada por imágenes (BTAGI). El objetivo de este estudio fue describir los resultados del protocolo de BTAGI de resonancia magnética del Servicio de Oncología del Hospital Carlos Van Buren. Métodos: En pacientes con CCLA tratadas con Radioquimioterapia concomitante seguida de BTAGI de resonancia magnética se evaluó la reducción tumoral, parámetros dosimétricos y la toxicidad aguda. Resultados: Se evaluó la reducción tumoral entre el diagnóstico y el momento de la braquiterapia en 34 pacientes. Todas las pacientes completaron el tratamiento de radioterapia externa. Veinticuatro pacientes recibieron 3 sesiones de braquiterapia. Dosis equivalentes totales > 80 Gy se logro en todos los pacientes. Doce pacientes presentaron reducción del volumen tumoral mayor al 70%. La mediana de las dosis equivalentes totales prescritas al D2cc de vejiga fue 73.9 Gy, al recto 65.6 Gy y al intestino fue de 69.1 Gy. Una paciente presento toxicidad gastrointestinal grado ≥ 3. No hubo diferencias estadísticamente significativas al comparar pacientes que recibieron dosis equivalentes totales desde los 85 Gy con las que recibieron menor dosis respecto a toxicidad gastrointestinal (p=0.33) y genitourinaria (p=0.97). Conclusión: La braquiterapia adaptativa guiada por resonancia magnética se puede realizar en el sistema público de salud y cumplir con las recomendaciones internacionales requeridas para el tratamiento estándar del CCLA.
Introduction and purpose: External beam radiation therapy with concomitant chemotherapy followed by adaptive image-guided brachytherapy (IGABT) is the standard of care for patients with locally advanced cervical cancer (LACC). The purpose of this study was to describe the local outcomes of the magnetic resonance IGABT protocol at the radiation oncology department of the Carlos Van Buren Hospital. Methods: Tumor reduction, dosimetric parameters and acute toxicity were evaluated in patients with LACC treated with concomitant radiochemotherapy followed by magnetic resonance IGABT. Results: Tumor reduction between diagnosis and brachytherapy was evaluated in 34 patients. All patients completed external radiation therapy treatment. Twenty-four patients received 3 sessions of brachytherapy. All patients received a total equivalent dose > 80 Gy. Twelve patients showed a tumor volume reduction greater than 70%. The median total equivalent dose prescribed to the bladder D2cc was 73.9 Gy, the rectum 65.6 Gy, and the intestine 69.1 Gy. One patient presented grade ≥ 3 gastrointestinal toxicity. No statistically significant differences were found when comparing patients who received total equivalent doses larger than 85 Gy with those who received lower doses regarding gastrointestinal (p = 0.33) and genitourinary (p = 0.97) toxicity. Conclusion: MRI-guided adaptive brachytherapy can be performed in the public health system and achieve the international recommendations required as standard of care treatment of LACC.
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Humanos , Femenino , Adulto , Persona de Mediana Edad , Braquiterapia/métodos , Imagen por Resonancia Magnética/métodos , Neoplasias del Cuello Uterino/radioterapia , Radioterapia Guiada por Imagen/métodos , Braquiterapia/efectos adversos , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/diagnóstico por imagen , Estudios Retrospectivos , Resultado del Tratamiento , QuimioradioterapiaRESUMEN
Eighty percent of hepatocarcinomas are inoperable at the moment of diagnosis. Liver transplantation is the treatment of choice in these cases, but local therapies are another alternative. Among these, Image-Guided BrachyAblation is a safe choice. We report a 76-year-old male with a hepatocarcinoma, who was considered inoperable due to the high surgical risk of the patient. A local treatment with Image-Guided BrachyAblation was decided. A brachytherapy needle was placed in the tumor under computed tomography guidance and a 15 Gy single dose was delivered from an Iridium-192 source. The patient had no immediate complications and at one month of follow up he continued without incidents.
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Técnicas de Ablación/métodos , Braquiterapia/métodos , Carcinoma Hepatocelular/radioterapia , Neoplasias Hepáticas/radioterapia , Radioterapia Guiada por Imagen/métodos , Anciano , Carcinoma Hepatocelular/diagnóstico por imagen , Humanos , Radioisótopos de Iridio , Neoplasias Hepáticas/diagnóstico por imagen , Masculino , Dosis de Radiación , Tomografía Computarizada por Rayos X , Resultado del TratamientoRESUMEN
Using Monte Carlo simulation and a realistic patient model, it is shown that the volume of healthy tissue irradiated at therapeutic doses can be drastically reduced using a combination of standard megavoltage and kilovoltage X-ray beams with a contrast agent previously loaded into the tumor, without the need to reduce standard treatment margins. Four-dimensional computed tomography images of 2 patients with a centrally located and a peripherally located tumor were obtained from a public database and subsequently used to plan robotic stereotactic body radiotherapy treatments. Two modalities are assumed: conventional high-energy stereotactic body radiotherapy and a treatment with contrast agent loaded in the tumor and a kilovoltage X-ray beam replacing the megavoltage beam (contrast-enhanced radiotherapy). For each patient model, 2 planning target volumes were designed: one following the recommendations from either Radiation Therapy Oncology Group (RTOG) 0813 or RTOG 0915 task group depending on the patient model and another with a 2-mm uniform margin determined solely on beam penumbra considerations. The optimized treatments with RTOG margins were imparted to the moving phantom to model the dose distribution that would be obtained as a result of intrafraction motion. Treatment plans are then compared to the plan with the 2-mm uniform margin considered to be the ideal plan. It is shown that even for treatments in which only one-fifth of the total dose is imparted via the contrast-enhanced radiotherapy modality and with the use of standard treatment margins, the resultant absorbed dose distributions are such that the volume of healthy tissue irradiated to high doses is close to what is obtained under ideal conditions.
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Neoplasias Pulmonares/radioterapia , Radiocirugia , Planificación de la Radioterapia Asistida por Computador , Radioterapia Guiada por Imagen , Relación Dosis-Respuesta en la Radiación , Humanos , Neoplasias Pulmonares/diagnóstico , Método de Montecarlo , Movimiento (Física) , Órganos en Riesgo , Intensificación de Imagen Radiográfica , Radiocirugia/métodos , Dosificación Radioterapéutica , Radioterapia Guiada por Imagen/métodos , Resultado del TratamientoRESUMEN
Eighty percent of hepatocarcinomas are inoperable at the moment of diagnosis. Liver transplantation is the treatment of choice in these cases, but local therapies are another alternative. Among these, Image-Guided BrachyAblation is a safe choice. We report a 76-year-old male with a hepatocarcinoma, who was considered inoperable due to the high surgical risk of the patient. A local treatment with Image-Guided BrachyAblation was decided. A brachytherapy needle was placed in the tumor under computed tomography guidance and a 15 Gy single dose was delivered from an Iridium-192 source. The patient had no immediate complications and at one month of follow up he continued without incidents.
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Humanos , Masculino , Anciano , Braquiterapia/métodos , Carcinoma Hepatocelular/radioterapia , Técnicas de Ablación/métodos , Radioterapia Guiada por Imagen/métodos , Neoplasias Hepáticas/radioterapia , Dosis de Radiación , Radioisótopos de Iridio , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Carcinoma Hepatocelular/diagnóstico por imagen , Neoplasias Hepáticas/diagnóstico por imagenRESUMEN
PURPOSE: To report a single-institutional experience with the use of magnetic resonance imaging (MRI)-guided radiotherapy for cancers of the head and neck. MATERIALS AND METHODS: Between October 2014 and October 2016, 18 patients with newly diagnosed cancers of the head and neck were prospectively enrolled on an institutional registry trial investigating the feasibility and efficacy of external-beam radiotherapy delivered using on-board MRI. All patients had biopsy-proven evidence of malignancy, measurable disease, and the ability to provide consent. None had previously received any treatment. Median dose was 70 Gy (range 54-70 Gy). MRI scans were obtained as part of an image-guided registration protocol for alignment prior to and during each treatment. Concurrent chemotherapy was administered to 14 patients (78%). Patient-reported outcomes were assessed using the University of Washington quality of life instrument. RESULTS: Seventeen of 18 patients completed the planned intensity-modulated radiotherapy (IMRT) treatment of which 15 (83%) had a complete response and 2 (11%) had a partial response based on initial post-therapy positron emission tomography (PET) at 3 months. The 1-year estimates of progression-free survival, overall survival, and local-regional control were 95, 96, and 95%, respectively. There were no treatment-related fatalities. The incidence of grade 3+ acute toxicity was 44%. The proportion of patients rating their health-related quality of life as "very good" or "outstanding" at 6 months and 1 year after completion of radiation therapy was 60 and 70%, respectively. CONCLUSIONS: MRI-guided radiotherapy achieves clinical outcomes comparable to contemporary series reporting on IMRT for head and neck cancer.
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Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/radioterapia , Imagen por Resonancia Magnética/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/métodos , Adolescente , Adulto , Anciano , Carcinoma de Células Escamosas/patología , Femenino , Estudios de Seguimiento , Neoplasias de Cabeza y Cuello/patología , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Prospectivos , Dosificación Radioterapéutica , Radioterapia de Intensidad Modulada/métodos , Tasa de Supervivencia , Adulto JovenRESUMEN
BACKGROUND: To investigate the efficacy and toxicity of 68Ga-PSMA-HBED-CC (68Ga-PSMA) PET-CT-guided RT in the treatment of oligometastatic prostate cancer retrospectively. METHODS: A total of 23 prostate cancer patients with biochemical relapse, of which 13 were castration sensitive (CS) and 10 castration resistant (CR), were treated with intensity-modulated and image-guided RT (IMRT-IGRT) on ≤3 metastases detected by 68Ga PSMA PET-CT. Androgen deprivation therapy was continued in CR patients. RESULTS: A total of 38 metastases were treated. The involved sites were pelvic bone (n = 16), pelvic lymph nodes (n = 11), paraaortic lymph nodes (n = 6), ribs (n = 3) and vertebral body (n = 2). The median PSA prior to RT was 1.1 ng/mL (range 0.1-29.0 ng/mL). A median dose of 43.5 Gy (range 30-64 Gy) was delivered by IMRT-IGRT in 12-27 fractions. At a median follow-up of 7 months (range 2-17 months), 19 patients (83%) were in remission. Four patients (17%) developed distant recurrences. The actuarial 1-year LC, PFS and OS rates were 100, 51 (95% CI 8-83%) and 100%. Univariate analysis demonstrated a statistically significantly better PFS in CS patients as compared to CR patients (1-year PFS 67 vs. 0%, p < 0.01). One patient experienced grade 2 acute gastrointestinal toxicity. Grade 3 or more toxicity events were not observed. CONCLUSIONS: By providing optimal LC, low toxicity and a promising PFS in CS patients, the current retrospective study illustrated that 68Ga PSMA PET-CT-guided RT may be an attractive treatment strategy in patients with oligometastatic prostate cancer. Validation by randomized trials is eagerly awaited.
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Metástasis de la Neoplasia/radioterapia , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Neoplasias de la Próstata/radioterapia , Radioterapia Guiada por Imagen/métodos , Anciano , Ácido Edético/análogos & derivados , Estudios de Factibilidad , Isótopos de Galio , Radioisótopos de Galio , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Oligopéptidos , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Radiofármacos , Radioterapia de Intensidad Modulada , Estudios RetrospectivosRESUMEN
ABSTRACT Purpose To evaluate quality of life (QoL) after post-prostatectomy intensity modulated radiation therapy (IMRT) in the "adjuvant" setting starting within 4 months of radical prostatectomy for adverse features; and "salvage" setting for a PSA≥0.2ng/mL. Materials and Methods Retrospective review of 130 patients who underwent IMRT to the prostate bed±gold fiducial marker placement for image guidance to 64.8-72.0Gy (median, 70.2Gy) between 2004 and 2013. Higher doses were defined as 70.2-72.0Gy and lower doses were defined as 64.8-68.4Gy. Androgen deprivation therapy (ADT) was given to 4/48 (8%) adjuvant patients and 9/82 (11%) salvage patients. International Prostate Symptom Score (IPSS), Sexual Health Inventory for Men (SHIM), and Expanded Prostate Cancer Index Composite-26-bowel (EPIC-26-bowel) questionnaires were used to assess urinary, sexual, and bowel QoL, respectively. Results Median follow-up was 46 months. There were better urinary (p=0.03) and sexual (p=0.002) QoL scores with adjuvant IMRT relative to salvage IMRT. The use of prostate bed fiducial markers did not significantly affect urinary, sexual, or bowel QoL (p=0.39, p=0.49, and p=0.40, respectively). Higher total radiotherapy doses did not significantly affect urinary, sexual, or bowel QoL (p=0.21, p=0.61, and p=0.36, respectively). Conclusions There was no significant change in urinary, sexual, and bowel sexual QoL with post-prostatectomy IMRT regardless of whether prostate bed fiducial markers or higher total radiotherapy doses were used. QoL with IMRT in the present study compares favorably with prior reports for three-dimensional conformal radiation therapy.
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Humanos , Masculino , Prostatectomía/psicología , Neoplasias de la Próstata/cirugía , Neoplasias de la Próstata/radioterapia , Calidad de Vida/psicología , Neoplasias de la Próstata/psicología , Estudios Retrospectivos , Estudios de Seguimiento , Resultado del Tratamiento , Terapia Recuperativa , Terapia Combinada , Radioterapia de Intensidad Modulada , Marcadores Fiduciales , Radioterapia Guiada por ImagenRESUMEN
PURPOSE: In image-based brachytherapy (IBBT), the dosimetry of small structures may be particularly sensitive to changes in contouring between imaging modalities. We therefore sought to characterize differences in urethral dosimetry in vaginal brachytherapy based on contouring on MRI vs. CT. METHODS AND MATERIALS: We retrospectively identified our most recent 15 patients treated with intracavitary brachytherapy for distal vaginal malignancies. On T2-weighted MRI, both the lumen and urethral wall were contoured. On CT, the urethral lumen alone was contoured, as the wall is indistinguishable from surrounding tissue. High-dose-rate (HDR) IBBT plans were generated for all patients. RESULTS: Mean urethral volume was higher on MRI than CT at 3.7 cc vs. 1.1 cc (p < 0.0005). As a result, there were statistically significant increases on MRI in D0.1cc and D0.5cc, as well as EQD2 D0.1cc and EQD2 D0.5cc when applied to a full course of treatment (45 Gy EBRT + 25 Gy IBBT). CONCLUSIONS: We have quantified the expected differences in urethral volume and dosimetry when contoured on MRI vs. CT. Inclusion of the urethral wall on MRI, with its average thickness of 2.2 mm, likely more accurately reflects the true organ at risk and results in an increase in reported dose compared to CT.