840 resultados para external beam radiotherapy


Relevância:

100.00% 100.00%

Publicador:

Resumo:

This study seeks to perform a survey of patterns of practice among the different physicians involved in the bone metastases management, with special focus on external beam radiotherapy (EBRT).A questionnaire about bone metastases based on clinical cases and supplemented with general questions, including medical therapies, EBRT and metabolic radiotherapy strategies, surgery, and supportive care approaches, was sent to 4,706 French-speaking physicians in Belgium, France, Luxemburg, and Switzerland.Overall, 644 questionnaires were analyzed. Twenty-eight percent concerned the radiotherapy approach and were judged adequate to respond to the part dedicated to EBRT. Sixty-nine percent of physicians used a total dose irradiation of 30 Gy delivered in ten fractions. A large majority (75%) used two opposed fields prescribed at mid-depth (30%), or with non-equally weighted fields (45%). Seventy percent irradiated also above and below the concerned vertebra. A dosimetry planning treatment was done in 85% and high-energy megavoltage photons were used in 42%. Moreover, 54% physicians used short course radiotherapy in routine.Radiotherapy remains the mainstay of treatment of bone metastases, but there is substantial heterogeneity in clinical practice. Guidelines and treatment protocols are required to improve the treatment quality.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

One-hundred patients treated with curative radiotherapy (RT) ± chemotherapy (CT) for an anal canal carcinoma (T1-4N0-3M0) were retrospectively analyzed. Five- and 10-year local control (LC) rates were 73% and 67%, respectively. Acute and late G3-G4 toxicity rates were 32% and 12%, respectively. Two patients underwent a colostomy for a G4 anal toxicity. This study confirms the outcomes of RT ± CT in the treatment of anal canal cancer. Concomitant CT and LC statistically influenced Overall Survival and Colostomy-Free Survival. CT also statistically reduced the risk of nodal relapse. High rates of acute skin toxicity impose tailored volumes and techniques of irradiation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: To determine the outcome of patients with brain metastasis (BM) from lung cancer treated with an external beam radiotherapy boost (RTB) after whole brain radiotherapy (WBRT). METHODS: A total of 53 BM patients with lung cancer were treated sequentially with WBRT and RTB between 1996 and 2008 according to our institutional protocol. Mean age was 58.8 years. The median KPS was 90. Median recursive partitioning analysis (RPA) and graded prognostic assessment (GPA) grouping were 2 and 2.5, respectively. Surgery was performed on 38 (71%) patients. The median number of BM was 1 (range, 1-3). Median WBRT and RTB combined dose was 39 Gy (range, 37.5-54). Median follow-up was 12.0 months. RESULTS: During the period of follow-up, 37 (70%) patients died. The median overall survival (OS) was 14.5 months. Only 13 patients failed in the brain. The majority of patients (n = 29) failed distantly. The 1-year OS, -local control, extracranial failure rates were 61.2%, 75.2% and 60.8%, respectively. On univariate analysis, improved OS was found to be significantly associated with total dose (< or = 39 Gy vs. > 39 Gy; p < 0.01), age < 65 (p < 0.01), absence of extracranial metastasis (p < 0.01), GPA > or = 2.5 (p = 0.01), KPS > or = 90 (p = 0.01), and RPA < 2 (p = 0.04). On multivariate analysis, total dose (p < 0.01) and the absence of extracranial metastasis (p = 0.03) retained statistical significance. CONCLUSIONS: The majority of lung cancer patients treated with WBRT and RTB progressed extracranially. There might be a subgroup of younger patients with good performance status and no extracranial disease who may benefit from dose escalation after WBRT to the metastatic site.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

To determine the outcome of patients with brain metastasis (BM) from lung cancer treated with an external beam radiotherapy boost (RTB) after whole brain radiotherapy (WBRT).

Relevância:

100.00% 100.00%

Publicador:

Resumo:

PURPOSE: To evaluate the efficacy of first-line chemotherapy (CT) in preventing external-beam radiotherapy (EBR) and/or enucleation in patients with retinoblastoma (Rbl). PATIENTS AND METHODS: Twenty-four patients with newly diagnosed unilateral or bilateral Rbl received CT associated with local treatment (LT). Two to five courses of etoposide and carboplatin were administered at 3- to 4-week intervals, depending on tumor response, and were completed each time by LT. RESULTS: Tumor response was observed in all eyes. Twenty-one of 24 patients showed a complete response (CR) that persisted at a median follow-up (FU) of 31 months (range, 4 to 41 months). Among the three patients who relapsed, two were lost to FU and one died of progressive disease. CR was achieved by CT and LT alone in 15 (71.4%) of 21 patients with less advanced disease (groups I to III). Six other patients with advanced disease (groups IV and V) experienced treatment failure and needed salvage treatment by EBR and/or enucleation. The difference between the two patient groups with regard to disease stage was statistically significant (P <.0001). EBR could be avoided in 13 (68.4%) of 19 patients, who presented with groups I to III (15 eyes) and group V (one eye) disease, whereas enucleation could be avoided in only two (40%) of five. CONCLUSION: CT combined with intensive LT is effective in patients with groups I to III Rbl, permitting the avoidance of EBR in the majority of these young children and, thus, reducing the risk of long-term sequelae. This is in contrast with the disappointing results for patients with groups IV and V Rbl, in whom EBR and/or enucleation was needed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

PURPOSE External beam radiation therapy is currently considered the most common treatment modality for intraocular tumors. Localization of the tumor and efficient compensation of tumor misalignment with respect to the radiation beam are crucial. According to the state of the art procedure, localization of the target volume is indirectly performed by the invasive surgical implantation of radiopaque clips or is limited to positioning the head using stereoscopic radiographies. This work represents a proof-of-concept for direct and noninvasive tumor referencing based on anterior eye topography acquired using optical coherence tomography (OCT). METHODS A prototype of a head-mounted device has been developed for automatic monitoring of tumor position and orientation in the isocentric reference frame for LINAC based treatment of intraocular tumors. Noninvasive tumor referencing is performed with six degrees of freedom based on anterior eye topography acquired using OCT and registration of a statistical eye model. The proposed prototype was tested based on enucleated pig eyes and registration accuracy was measured by comparison of the resulting transformation with tilt and torsion angles manually induced using a custom-made test bench. RESULTS Validation based on 12 enucleated pig eyes revealed an overall average registration error of 0.26 ± 0.08° in 87 ± 0.7 ms for tilting and 0.52 ± 0.03° in 94 ± 1.4 ms for torsion. Furthermore, dependency of sampling density on mean registration error was quantitatively assessed. CONCLUSIONS The tumor referencing method presented in combination with the statistical eye model introduced in the past has the potential to enable noninvasive treatment and may improve quality, efficacy, and flexibility of external beam radiotherapy of intraocular tumors.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The ultimate check of the actual dose delivered to a patient in radiotherapy can only be achieved by using in vivo dosimetry. This work reports a pilot study to test the applicability of a thermoluminescent dosimetric system for performing in vivo entrance dose measurements in external photon beam radiotherapy. The measurements demonstrated the value of thermoluminescent dosimetry as a treatment verification method and its applicability as a part of a quality assurance program in radiotherapy. (c) 2009 Elsevier Ltd. All rights reserved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background and purpose: To evaluate biochemical control and treatment related toxicity of patients with localized adenocarcinoma of the prostate treated with high dose-rate brachytherapy (HDRB) combined with conventional 2D or 3D-conformal external beam irradiation (EBI). Material and methods: Four-hundred and three patients treated between December 2000 and March 2004. HDRB was delivered with three fractions of 5.5-7 Gy with a single implant, followed by 45 Gy delivered with 2D or 3D conformal EBI. Results: The median follow-up was 48.4 months. Biochemical failure (BF) occurred in 9.6% according to both ASTRO and Phoenix consensus criteria. Mean time to relapse was 13 and 26 months, respectively. The 5-year BF free survival using the ASTRO criteria was 94.3%, 86.9% and 86.6% for the low, intermediate and high risk groups, respectively; using Phoenix criteria, 92.4%, 88.0% and 85.3%, respectively. The only predictive factor of BF in the multivariate analysis by both ASTRO and Phoenix criteria was the presence of prostate nodules detected by digital palpation, and patients younger than 60 years presented a higher chance of failure using Phoenix criteria only. Conclusions: Treatment scheme is feasible and safe with good efficacy. (C) 2011 Elsevier Ireland Ltd All rights reserved. Radiotherapy and Oncology 98 (2011) 169-174

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Dissertação para obtenção do Grau de Doutor em Engenharia Biomédica

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Hemorrhagic gastritis is a possible late toxicity outcome after radical radiotherapy but it is nowadays a very rare condition and most likely depends on other clinical factors. We report the case of a 77-year-old woman with a symptomatic solitary extramedullary intra-abdominal plasmacytoma and multiple gastric comorbidities, treated with external beam radiotherapy. Despite the good response to radiotherapy, the patient experienced multiple gastric bleeding a few months later, with the need of multiple treatments for its control. In this paper we will discuss in detail all aspects related to the different causes of hemorrhagic gastritis.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

INTRODUCTION: Melanoma of the iris and ciliary body may be associated with secondary glaucoma. Treatment with proton beam radiotherapy (PBRT) to the anterior segment can also elevate intraocular pressure (IOP), resulting in uncontrolled glaucoma, often requiring enucleation. This is the first prospective study of Baerveldt aqueous shunts in irradiated eyes with anterior uveal melanoma (AUM; affecting the iris or ciliary body). METHODS: Thirty-one eyes with uncontrolled IOP following anterior segment PBRT treatment for AUM were prospectively recruited to undergo Baerveldt shunt implantation. Postoperative examinations were performed on day 1; weeks 1, 3, 6, 9; months 3, 6, 9, 12 and annually thereafter. Surgical success was defined as IOP 21 mm Hg or less and 20% reduction from baseline. All complications were recorded. RESULTS: Mean follow-up was 15.7 months (SD ±8.3 months). Mean interval from irradiation to shunt implantation was 2.5 years. Mean preoperative IOP was 31.0 (±10.3) mm Hg; mean IOP at last visit was 15.0 (±5.0) mm Hg; mean pre-operative glaucoma medications were 3.3 (±1.3); postoperatively 0.7 (±1.3) glaucoma medications. Surgical success rate was 86% using glaucoma medications. Four eyes had minor postoperative complications, none of which were sight threatening. There were no local tumour recurrences or systemic metastases. There were no enucleations caused by ocular hypertension. CONCLUSIONS: Baerveldt shunts were effective in lowering IOP, with few complications, in eyes treated with total anterior segment irradiation for AUM.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

AIM: We investigated the prognostic significance of intraductal carcinoma of the prostate (IDC-P) in biopsies and transurethral resections prior to external beam radiotherapy with or without androgen deprivation. METHODS: Cohort 1 consisted of 118 intermediate risk prostate cancer patients treated by radiotherapy, with biochemical relapse as primary end-point (median follow-up 6.5 years). Cohort 2 consisted of 132 high risk patients, enrolled in a phase III randomised trial (EORTC 22863) comparing radiotherapy alone to radiotherapy with long-term androgen deprivation (LTAD) with clinical progression free survival as primary end-point (median follow-up 9.1 years). Presence of IDC-P was identified after central review. Multivariable regression modelling and Kaplan-Meier analysis were performed with IDC-P as dichotomous variable. RESULTS: IDC-P was a strong prognosticator for early (<36 months) biochemical relapse (HR 7.3; p = 0.007) in cohort 1 and for clinical disease-free survival in both arms of cohort 2 (radiotherapy arm: HR 3.5; p < 0.0001; radiotherapy plus LTAD arm: HR 2.8, p = 0.018). IDC-P retained significance after stratification for reviewed Gleason score in the radiotherapy arm (HR 2.3; p = 0.03). IDC-P was a strong prognosticator for metastatic failure rate (radiotherapy arm: HR 5.3; p < 0.0001; radiotherapy plus LTAD arm: HR 3.6; p = 0.05). CONCLUSIONS: IDC-P in diagnostic samples of patients with intermediate or high risk prostate cancer is an independent prognosticator of early biochemical relapse and metastatic failure rate after radiotherapy. We suggest that the presence of IDC-P in prostate biopsies should routinely be reported.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

AIM: To report on trans-scleral local resection of choroidal melanoma for exudative retinal detachment and neovascular glaucoma (toxic tumour syndrome) after proton beam radiotherapy (PBR). METHODS: A non-randomised, prospective study of secondary trans-scleral local resection of choroidal melanoma for exudative retinal detachment with or without neovascular glaucoma after PBR. The patients were treated at the Liverpool Ocular Oncology Centre between February 2000 and April 2008. The trans-scleral local resection was performed with a lamellar-scleral flap, using systemic hypotension to reduce haemorrhage. RESULTS: 12 patients (six women, six men) with a mean age of 51 years (range 20-75) were included in this study. The tumour margins extended anterior to ora serrata in six patients. On ultrasonography, the largest basal tumour dimension averaged 12.4 mm (range 6.8-18.1) and the tumour height averaged 7.1 mm (range 4.2-10.7). The retinal detachment was total in seven patients. Neovascular glaucoma was present in four patients. The time between PBR and local resection had a mean of 17.4 months (range 1-84). The ophthalmic follow-up time after the local resection had a mean of 46.2 months (range 14-99). At the latest known status, the eye was conserved in 10 patients, with a flat retina in all these patients and visual acuity equal or better than 6/30 in four patients. The reasons for enucleation were: patient request for enucleation when rhegmatogenous retinal detachment complicated the resection (one patient) and phthisis (one patient). CONCLUSIONS: Exudative retinal detachment, rubeosis and neovascular glaucoma after PBR of a choroidal melanoma can resolve after trans-scleral local resection of the tumour. Our findings suggest that these complications are caused by the persistence of the irradiated tumour within the eye ('toxic tumour syndrome').

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: Collateral damage to upper eyelid margin during proton beam radiotherapy (PBR) for choroidal melanoma may cause squamous metaplasia of the tarsal conjunctiva with keratinisation, corneal irritation, discomfort and, rarely, corneal perforation. We evaluated transpalpebral PBR as a means of avoiding collateral damage to the upper eyelid margin without increasing the risk of failure of local tumour control. METHODS: Retrospective study of consecutive patients who underwent PBR for choroidal melanoma between 1992 and 2007 at the Royal Liverpool University Hospital and the Douglas Cyclotron at Clatterbridge Cancer Centre, UK. RESULTS: Sixty-three patients were included in this study. Mean basal tumour diameter and tumour thickness were 11.8 mm and 3.6 mm, respectively. PBR mean beam range and modulation were 26.5 mm and 16.9 mm respectively. The eyelid margin was included in the radiation field in 15 (24%) eyes. The median follow-up was 2.5 years. Local tumour recurrence developed in 2 (3.2%) patients. In these two cases that developed tumour recurrence the transpalpebral treatment did not involve the eyelid margin. Six (9.5%) patients died of metastatic disease. No eyelid or ocular surface problems developed in any of the 48 patients who were treated without eyelid rim involvement, while 7 of the 15 patients with unavoidable irradiation of the eyelid rim developed some degree of madarosis. These seven patients all received more than 26.55 proton Gy to the eyelid margin. Symptoms, such as grittiness occurred in 12% of 48 patients without eyelid margin irradiation as compared with 53% of 15 patients whose lid margin was irradiated. CONCLUSIONS: Transpalpebral PBR of choroidal melanoma avoids eyelid and ocular surface complications without increasing failure of local tumour control.