Uso de PET-CT en el delineado de volumen en la planificación del tratamiento con radiación / Use of PET-CT in the one delineated of volume in the planning of the one radiant treatment

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.

Image-Guided BrachyAblation (IGBA) en hepatocarcinoma: descripción de la técnica y reporte del primer caso en Chile / Image-guided brachyablation for hepatocarcinoma: report of one case

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.

Spine radiosurgery for the local treatment of spine metastases: Intensity-modulated radiotherapy, image guidance, clinical aspects and future directions

Many cancer patients will develop spinal metastases. Local control is important for preventing neurologic compromise and to relieve pain. Stereotactic body radiotherapy or spinal radiosurgery is a new radiation therapy technique for spinal metastasis that can deliver a high dose of radiation to a tumor while minimizing the radiation delivered to healthy, neighboring tissues. This treatment is based on intensity-modulated radiotherapy, image guidance and rigid immobilization. Spinal radiosurgery is an increasingly utilized treatment method that improves local control and pain relief after delivering ablative doses of radiation. Here, we present a review highlighting the use of spinal radiosurgery for the treatment of metastatic tumors of the spine. The data used in the review were collected from both published studies and ongoing trials. We found that spinal radiosurgery is safe and provides excellent tumor control (up to 94% local control) and pain relief (up to 96%), independent of histology. Extensive data regarding clinical outcomes are available; however, this information has primarily been generated from retrospective and nonrandomized prospective series. Currently, two randomized trials are enrolling patients to study clinical applications of fractionation schedules spinal Radiosurgery. Additionally, a phase I clinical trial is being conducted to assess the safety of concurrent stereotactic body radiotherapy and ipilimumab for spinal metastases. Clinical trials to refine clinical indications and dose fractionation are ongoing. The concomitant use of targeted agents may produce better outcomes in the future.

Effect of sugarcane biopolymer in vocal fold of rabbits. Comparative study with calcium hydroxyapatite

PURPOSE: To compare the inflammatory reaction caused by the injection of a sugarcane biopolymer (SCB) into the vocal fold of rabbits with that caused by calcium hydroxyapatite (CaH). METHODS: CaH (Radiesse(r)) and SCB gel were injected respectively into the right and left vocal cords of thirty rabbits. The rabbits were distributed into two equal groups and sacrificed at three and twelve weeks after injection. We then evaluated the intensity of the inflammatory reaction, plus levels of neovascularization, fibrogenesis and inflammatory changes in the vocal mucosa. RESULTS: The vocal cords injected with CaH had a stronger inflammatory reaction by giant cells in both study periods. The SCB group had a more intense inflammatory involvement of polymorphonuclear cells three weeks after injection. SCB caused a higher level of neovascularization compared with CaH three weeks after the procedure. CONCLUSION: Whereas calcium hydroxyapatite triggers a more intense and lasting inflammatory reaction mediated by giant cells, sugarcane biopolymer causes a greater response from polymorphonuclear leukocytes, as well as higher levels of vneoascularization three weeks after injection. .

Stereotactic Body Radiation Therapy for Low- to Intermediate-risk Prostate Adenocarcinoma

The aim of the present study was to evaluate the efficacy and toxicity of stereotactic body radiation therapy (SBRT) for low- to intermediate-risk prostate adenocarcinoma. Thirty-nine patients were retrospectively reviewed. The SBRT was delivered using the CyberKnife with the fiducial tracking method combined with In-tempo imaging. The gross target volume, which included the prostate only, was delineated on the fused CT/MRI scans. The prescription dose was delivered every other day as 5 fractions of 7.5 Gy. Venous blood was obtained before and after SBRT to assess the prostate-specific antigen (PSA) level. Toxicity was evaluated using the CTCAE, v4.03. The median follow-up time was 30.0 months. The median initial PSA level was 7.7 ng/mL. PSA levels decreased in all patients treated with SBRT, and after 5 months, the median PSA was less than 2 ng/mL. The rate of overall 3-yr actuarial biochemical failure free survival was 93.9%. Acute side effects were generally comparable with those of previous studies. The PSA change and toxicity after SBRT for low- to intermediate-risk prostate adenocarcinoma indicates favorable biochemical responses and tolerable levels of toxicity. Additionally short course treatment may produce cost benefit and convenience to patients.

Lipiodol as a Fiducial Marker for Image-Guided Radiation Therapy for Bladder Cancer

Purpose To evaluate Lipiodol as a liquid, radio-opaque fiducial marker for image-guided radiation therapy (IGRT) for bladder cancer.Materials and Methods Between 2011 and 2012, 5 clinical T2a-T3b N0 M0 stage II-III bladder cancer patients were treated with maximal transurethral resection of a bladder tumor (TURBT) and image-guided radiation therapy (IGRT) to 64.8 Gy in 36 fractions ± concurrent weekly cisplatin-based or gemcitabine chemotherapy. Ten to 15mL Lipiodol, using 0.5mL per injection, was injected into bladder submucosa circumferentially around the entire periphery of the tumor bed immediately following maximal TURBT. The authors looked at inter-observer variability regarding the size and location of the tumor bed (CTVboost) on computed tomography scans with versus without Lipiodol.Results Median follow-up was 18 months. Lipiodol was visible on every orthogonal two-dimensional kV portal image throughout the entire, 7-week course of IGRT. There was a trend towards improved inter-observer agreement on the CTVboost with Lipiodol (p = 0.06). In 2 of 5 patients, the tumor bed based upon Lipiodol extended outside a planning target volume that would have been treated with a radiation boost based upon a cystoscopy report and an enhanced computed tomography (CT) scan for staging. There was no toxicity attributable to Lipiodol.Conclusions Lipiodol constitutes a safe and effective fiducial marker that an urologist can use to demarcate a tumor bed immediately following maximal TURBT. Lipiodol decreases inter-observer variability in the definition of the extent and location of a tumor bed on a treatment planning CT scan for a radiation boost.