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1.
Phys Med ; 65: 227-237, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574356

RESUMO

Microbeam radiation therapy (MRT) uses synchrotron arrays of X-ray microbeams to take advantage of the spatial fractionation effect for normal tissue sparing. In this study, radiochromic film dosimetry was performed for a treatment where MRT is introduced as a dose boost in a hypofractionated stereotactic radiotherapy (SRT) scheme. The isocenter dose was measured using an ionization chamber and two dimensional dose distributions were determined using radiochromic films. To compare the measured dose distribution to the MRT treatment plan, peak and valley were displayed in separate dosemaps. The measured and computed isocenter doses were compared and a two-dimensional 2%/2 mm normalized γ-index analysis with a 90% passing rate criterion was computed. For SRT, a difference of 2.6% was observed in the dose at the isocenter from the treatment plan and film measurement, with a passing rate of 96% for the γ-index analysis. For MRT, peak and valley doses differences of 25.6% and 8.2% were observed, respectively but passing rates of 96% and 90% respectively were obtained from the normalized γ-index maps. The differences in isocenter doses measured in MRT should be further investigated. We present the methodology of patient specific quality assurance (QA) for studying MRT dose distributions and discuss ideas to improve absolute dosimetry. This patient specific QA will be used for large animal trials quality assurance where MRT will be administered as a dose boost in conventional SRT. The observed remaining discrepancies should be studied against approximations in the TPS phantom materials, beams characteristics or film read-out procedures.


Assuntos
Dosimetria Fotográfica/métodos , Radioterapia/métodos , Neoplasias Encefálicas/radioterapia , Fracionamento da Dose de Radiação , Humanos , Imagens de Fantasmas , Radiometria/métodos , Dosagem Radioterapêutica , Síncrotrons , Raios X
2.
Medicine (Baltimore) ; 98(39): e17340, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574873

RESUMO

Radiotherapy after breast-conserving surgery or mastectomy has clinical benefits including reducing local recurrence and improving overall survival. Deep inspiration breath-hold (DIBH) technique using the Abches system is an easy and practical method to reduce radiation dose to the heart and lungs. This retrospective study was proposed to investigate the dosimetric difference between Abches system and free breathing technique in treating left-sided breast cancer.Eligible patients underwent computed tomography (CT) scans to acquire both free breathing (FB) and DIBH technique data using the Abches. For each patient, both FB and DIBH image sets were planned based on the volumetric modulated arc therapy (VMAT). Radiation dose to the heart, ipsilateral lung, and contralateral lung was compared between the Abches system and FB.No significant differences in the planning target volume (PTV) (674.58 vs 665.88 cm, P = .29), mean dose (52.28 vs 52.03 Gy, P = .13), and volume received at the prescribed dose (Vpd) (94.66% vs 93.92%, P = .32) of PTV were observed between the FB and DIBH plans. Significant differences were found in mean heart (6.71 Gy vs 4.21 Gy, P < .001), heart V5 (22.73% vs 14.39%, P = .002), heart V20 (10.96% vs. 5.62%, P < .001), mean left lung (11.51 vs 10.07 Gy, P = .01), left lung V20 (22.88% vs 19.53%, P = .02), left lung V30 (18.58 vs 15.27%, P = .005), and mean right lung dose (.89 vs 72 Gy, P = .03).This is the first report on reduced mean left lung, mean right lung dose, and V20 of left lung using VMAT and Abches. The combination of Abches and VMAT can practically and efficiently reduce extraradiation doses to the heart and lungs.


Assuntos
Radioterapia de Intensidade Modulada/métodos , Terapia Respiratória/métodos , Neoplasias Unilaterais da Mama/radioterapia , Adulto , Idoso , Suspensão da Respiração , Terapia Combinada , Feminino , Coração/efeitos da radiação , Humanos , Inalação , Pulmão/efeitos da radiação , Mastectomia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Órgãos em Risco/efeitos da radiação , Dosagem Radioterapêutica , Estudos Retrospectivos , Resultado do Tratamento
3.
Anticancer Res ; 39(10): 5689-5693, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570468

RESUMO

BACKGROUND/AIM: To evaluate the association between osteoradionecrosis (ORN) of the mandible and stenosis of the external carotid artery after radiation therapy (RT) for head and neck cancer. PATIENTS AND METHODS: The computed tomography images of 42 patients (36 men, six women; median age, 64.5 years) treated with RT for head and neck cancer between January 2011 and December 2015 were reviewed. The cross-sectional diameters of the bilateral external carotid arteries were measured on contrast-enhanced images taken after completion of RT. RESULTS: Nine of the 42 included patients (21.4%) developed ORN after a median interval of 34 months from completion of RT. Univariate analysis revealed that external carotid artery diameter ≤ the median diameter was significantly associated with ORN development (p=0.008 and 0.013). In multivariate analysis, left external carotid artery diameter ≤ the median was significantly associated with ORN development (p=0.023). CONCLUSION: External carotid artery stenosis was significantly associated with ORN development.


Assuntos
Artéria Carótida Externa/patologia , Mandíbula/patologia , Osteorradionecrose/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estenose das Carótidas/patologia , Estudos Transversais , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Fatores de Risco
4.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 75(10): 1135-1140, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31631106

RESUMO

Radiotherapy linear accelerators are calibrated to deliver a specific dose under standard conditions following accepted protocols (for example, JSMP12 protocol). The linear accelerator output is calibrated to deliver 1.0 cGy per 1.0 monitor unit (MU) at the depth of maximum in tissue maximum ratio. Beams of photons or electrons pass through a monitor chamber located in the linear accelerators head, which turns off the beam once the prescribed MU is delivered. The clinical outcome of radiotherapy demands that the linear accelerators output do not deviate from the calibrated level by more than a few percent. The purpose of this study is to characterize and understand the long term behavior of the output, change of flatness and symmetry from megavoltage radiotherapy linear accelerators (TrueBeam, Varian Medical Systems). Output trends of beams from three linear accelerators in two institutions over a period of more than 3 years are reported and analyzed. Output taken once per month the basis of this study. The output is measured using ionization chamber with water phantom. These are calibrated by accredited dosimetry laboratory with Japanese traceability system. When the output variation was bounded ±1%, monitor chamber was re-calibrated. The results show that the output from Linac was constantly upward trend. The output of Linac increased up to 8.0% in 1st year. However, upward trend became plateau slowly after years. Beams of same energies from another Linac are correlated with a correlation coefficient. Symmetry and flatness from one Truebeam stabled within 1%. If these adjustments are artificially removed then there is an increase in output, it is important to check the output of linear accelerator periodically.


Assuntos
Aceleradores de Partículas , Fótons , Elétrons , Imagens de Fantasmas , Radiometria , Dosagem Radioterapêutica
5.
Nihon Hoshasen Gijutsu Gakkai Zasshi ; 75(10): 1150-1157, 2019.
Artigo em Japonês | MEDLINE | ID: mdl-31631108

RESUMO

In this paper, we proposed an efficient quality assurance method which can measure direct tissue maximum ratio (TMRDir), total scatter factor (Scp, Dir), wedge factor (WFDir), tissue phantom ratio 20/10 (TPR20/10Dir) by using a calibration water phantom and a Farmer chamber. The TMRDir was compared with the calculated TMR (TMRCal) that was calculated from the percentage depth dose at the time of the linear accelerator installation. Scp, Dir, WFDir and TPR20/10Dir calculated from TMRDir were compared with Scp, BD, WFBD, and TPR20/10BD measured at the time of the linear accelerator installation. The difference between TMRDir and TMRCal was approximately within 1% except for using 60° wedge filter. The difference between Scp, Dir and Scp, BD was within 1%, between WFDir and WFBD was within 2%, between TPR20/10Dir and TPR20/10BD was within 1%, these differences were acceptable levels of AAPM TG-142 report. Also, coefficient of variation (CV) of TMRDir, ScpDir, WFDir and TPR20/10Dir when changing days and measuring multiple times were approximately within 1%, these CVs were reference levels of AAPM TG-106 report. We validated that was an efficient quality assurance method by measuring direct tissue maximum ratio, but the propose method has limited in measurable field size.


Assuntos
Aceleradores de Partículas , Água , Calibragem , Imagens de Fantasmas , Radiometria , Dosagem Radioterapêutica
6.
Gan To Kagaku Ryoho ; 46(8): 1219-1225, 2019 Aug.
Artigo em Japonês | MEDLINE | ID: mdl-31501360

RESUMO

Although local tumor controls in various cancers by radiation therapy(RT)are dose dependent, dose-volume effects on late toxicities of surrounding normal tissues have been also observed. Particle beam therapy(PBT)using protons and carbonions have physical advantages in RT for the treatment of various cancers because they can create a desirable dose distribution to the target volume using fewer portals compared with photon-based RT. Thus, dose-escalation using charged particles is a reasonable approach in RT, theoretically. Based on accumulation of the evidences that PBT shows the efficacy in treatment for several cancers, the number of particle therapy facilities have been rapidly increasing worldwide. The Japanese Society for Radiation Oncology organized a joint effort among research groups to establish standardized treatment policies of particle therapy according to disease through systematic reviews. Furthermore, multicenter prospective studies have been conducted for hepatocellular carcinoma and prostate cancer. At the present, PBT for pediatric tumors, prostate cancer, unresectable bone and soft tissue sarcomas, head and neck non-squamous cell carcinomas is covered by the Japanese national health insurance system. Boron neutron capture therapy(BNCT)is also a promising modality as biochemically targeted RT, but it has been performed in only limited facilities. Recent advances in technology, accelerator-based neutron sources will increase in BNCT facilities and lead to wider application of BNCT for various cancers.


Assuntos
Terapia por Captura de Nêutron de Boro , Neoplasias/radioterapia , Humanos , Masculino , Estudos Prospectivos , Dosagem Radioterapêutica
7.
Anticancer Res ; 39(9): 5065-5069, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31519616

RESUMO

BACKGROUND/AIM: The primary endpoint of this phase I study was the maximum tolerated dose (MTD) of middle half body (MHB) accelerated radiotherapy (RT) in multiple bone metastatic (BM) prostate cancer (PCa) patients. PATIENTS AND METHODS: Three step dose escalation [13 Gy (3.25 Gy/fraction), 14 Gy (3.5 Gy/fraction), and 15 Gy (3.75 Gy/fraction)] in three consecutive patient cohorts were planned. RT was delivered in two consecutive days and two daily fractions. Six patients were enrolled in the first two cohorts and 12 in the third cohort. Grade ≥3 toxicity was considered as a dose-limiting toxicity (DLT). RESULTS: Twenty-five patients (median age=71 years, median follow-up=7.4 months) were enrolled. Defined MTD dose was 15 Gy. Overall pain response rate was 76%: 9 patients (36%) showed complete and 10 patients (40%) reported partial response of pain. CONCLUSION: MHB accelerated RT (total dose: 15 Gy) delivered in two consecutive days and two daily fractions is well tolerated.


Assuntos
Neoplasias Ósseas/radioterapia , Neoplasias Ósseas/secundário , Neoplasias da Próstata/patologia , Radioterapia , Idoso , Terapia Combinada , Seguimentos , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Qualidade de Vida , Radioterapia/efeitos adversos , Radioterapia/métodos , Dosagem Radioterapêutica , Resultado do Tratamento
9.
Jpn J Clin Oncol ; 49(7): 664-670, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505651

RESUMO

OBJECTIVES: Although mucosa-associated lymphoid tissue lymphoma (MALToma) is sensitive to radiation therapy (RT), the optimal RT dose and treatment volumes have not been established. This study aimed to assess the relapse patterns and outcomes of patients with orbital MALToma who underwent RT and to suggest implications for optimized RT. METHODS: We reviewed 212 patients (246 orbits) diagnosed with orbital MALToma who received RT between 1993 and 2013. Median RT dose was 25.2 Gy. Generally, conjunctival and eyelid lesions were irradiated with electrons, whereas retrobulbar and lacrimal gland lesions with photons. Lens shielding was used for 70% of treated eyes, mainly conjunctival and eyelid tumors. RESULTS: Relapse occurred in 29 patients. Among 11 patients with local relapse (LR), 4 were attributed to insufficient dose (n = 2) and improper RT volume (n = 2). The 10-year LR, contralateral orbit relapse, and distant relapse rates were 8.6%, 12.8% and 4.9%, respectively. Twelve patients died of disease-specific causes (n = 1) and intercurrent diseases (n = 11). The 10-year relapse-free survival, overall survival, and cause-specific survival rates were 69.7%, 88.2% and 98.8%, respectively. Grade 3 cataracts and nasolacrimal duct obstruction were observed in 27 and 4 orbits, respectively. CONCLUSION: Low-dose RT with proper lens shielding is an appropriate treatment for orbital MALToma in terms of high disease control rate and acceptable morbidity. However, lower RT dose may be attempted to further reduce toxicity while maintaining excellent outcomes.


Assuntos
Linfoma de Zona Marginal Tipo Células B/radioterapia , Membrana Mucosa/patologia , Recidiva Local de Neoplasia/radioterapia , Neoplasias Orbitárias/radioterapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Linfoma de Zona Marginal Tipo Células B/patologia , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Terapia de Salvação , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
10.
Cancer Radiother ; 23(6-7): 773-777, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31471250

RESUMO

The conservative treatment of squamous cell carcinoma of anal canal by irradiation is recommended as first indication. Despite its rarity, significant improvements were obtained by retrospective or prospective clinical studies these 20 past years, evaluating concomitant chemotherapy and IMRT. Nevertheless, the individualisation of the treatment, over dose distribution, has poor data available. Fractionation remains classic (1.8-2.0Gy/Fr), but the optimal dose level remains under discussion. The strategy concerning the volumes and doses for the prophylactic volumes remains under discussion. This paper will describe the data published, and the recommendations of working Groups, and the main options under evaluation. To conclude, today only the absence of gap is recommended, the benefit of a one-step schedule reducing the treatment time, then increasing local control and survival, but personalised schedules remain under investigation.


Assuntos
Neoplasias do Ânus/radioterapia , Carcinoma de Células Escamosas/radioterapia , Irradiação Linfática/métodos , Medicina de Precisão/métodos , Neoplasias do Ânus/patologia , Carcinoma de Células Escamosas/patologia , Tratamento Conservador/métodos , Humanos , Estadiamento de Neoplasias , Guias de Prática Clínica como Assunto , Estudos Prospectivos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos
11.
Cancer Radiother ; 23(6-7): 720-731, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31471255

RESUMO

Stereotactic radiotherapy (or Stereotactic body radiotherapy [SBRT]) is a technique currently well established in the therapeutic arsenal for the management of bronchial cancers. It represents the standard treatment for inoperable patients or who refuses surgery. It is well tolerated, especially in elderly and frail patients, and the current issue is to define its indications in operated patients, based on retrospective and randomized trials comparing stereotactic radiotherapy and surgery, with results equivalents. This work analyzes in detail the different aspects of pulmonary stereotactic radiotherapy and suggests arguments that help in the therapeutic choice between surgery and stereotaxic irradiation. In all cases, the therapeutic decision must be discussed in a multidisciplinary consultation meeting, while informing the patient of the possible therapeutic options.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/radioterapia , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Fatores Etários , Idoso , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Tomada de Decisão Clínica , Humanos , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/patologia , Neoplasias Pulmonares/cirurgia , Dosagem Radioterapêutica , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Retrospectivos , Equipolência Terapêutica
12.
Artigo em Japonês | MEDLINE | ID: mdl-31548467

RESUMO

PURPOSE: Intensity modulated radiation therapy (IMRT) has become a widely accepted and efficient treatment technique for many types of cancers. Patient's specific quality assurance (QA) should be performed with QA devices. Stability and sensitivity tests conducted on the ArcCHECK (AC) 3D diode array were performed. METHODS: Set-up error test with AC was performed. The set-up position moved to lateral (mm), longitudinal (mm) and rotational (°) were 0.5, 1.0, 2.0 and 3.0, respectively. Sensitivity change test of diode array with AC through 230 days was also performed. Same array calibration data was applied to all measurements of volumetric-modulated arc therapy benchmark test through 230 days. Gamma method (2 mm/2% criteria) was performed to analyze the result of all measurements. RESULTS: In the results of positional error, gamma pass rate become degenerate according to positional error became larger. With 0.5 mm or 0.5° positional error, decreasing rate of the pass rate of lateral, longitudinal and rotational were 1.0%, 2.5% and 4.2%, respectively. In the sensitivity change test, the gamma pass rate decreased 2.2%/100 days with same calibration data. CONCLUSION: AC has highly sensitivity against positional error. Sensitivity of AC has been changed and pass rate was decreased 2.2%/100 days through 230 days. Array calibration should be performed in consideration of change of sensitivity.


Assuntos
Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Calibragem , Humanos , Garantia da Qualidade dos Cuidados de Saúde , Radiometria , Dosagem Radioterapêutica
13.
Cancer Radiother ; 23(6-7): 581-591, 2019 Oct.
Artigo em Francês | MEDLINE | ID: mdl-31473088

RESUMO

Intensity modulated radiotherapy combined with image guided radiotherapy has led to increase the precision of external beam radiotherapy. However, intra or inter-fraction anatomical variations are frequent during the treatment course and can cause under-dosing of the target volume and/or over-dosing of the organs at risk. Several adaptive radiotherapy (ART) strategies can be defined to compensate these anatomical variations. The purpose of this article is to provide an overview of available ART strategies: offline, online, hybrid (library of treatment plans) or in real-time, while considering the arrival of MR-Linac devices in radiotherapy departments. The tools required to these ART strategies such as auto-segmentation, deformable image registration, calculation of the daily dose or dose accumulation, are also described. Implementing an ART strategy requires a rigorous quality assurance process, at each stage and on the entire workflow, as well as prior organization and training from of all the trades. A strong multidisciplinary involvement is finally required in order to ensure ART treatments.


Assuntos
Órgãos em Risco/efeitos da radiação , Garantia da Qualidade dos Cuidados de Saúde , Lesões por Radiação/prevenção & controle , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/métodos , Radioterapia de Intensidade Modulada/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Humanos , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Neoplasias/radioterapia , Dosagem Radioterapêutica , Radioterapia de Alta Energia , Radioterapia Guiada por Imagem/instrumentação , Radioterapia de Intensidade Modulada/instrumentação
14.
Int J Nanomedicine ; 14: 5865-5874, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534328

RESUMO

Purpose: To investigate the effect of precise modeling for Monte Carlo simulations of gold nanoparticles (GNPs) dose-enhanced radiotherapy, two models characterized by their distribution of GNPs in a simulated macroscopic cubic tumor were introduced. The motivation was the widely documented tendency of GNPs to localize around the cell nucleus. Methods: The introduced models composed of 2.7×107 ellipsoid cells, each of them containing a centrally located nucleus as the target for dose evaluation. In the first model, the spheres of GNP are homogeneously distributed in the whole tumor volume, and in the latter, GNPs are localized in the cytoplasms surrounded the nuclei. Results: The results achieved through applying Monte Carlo radiation transports using the Mont Carlo N-Particle eXtended code (MCNPX) show an underestimation of nuclear dose enhancement caused by homogeneous model compared with that of heterogeneous distribution. By investigating various quantities, it was found that subcellular location of GNPs strongly governs the sensitivity of dose enhancement to the number and concentration of GNPs targeted in the tumor. Other obvious differences are revealed by studying the dose enhancement curves in depth of the tumor. While the heterogeneous model predicts an approximately constant dose enhancement in depth for primary photon energies of 50 keV and more, the homogeneous model estimates an energy-dependent increase of about 11 to 30%. Conclusion: It can be concluded that defining a model in accordance with the experimental observations can effectively account for accurate prediction of macroscopic dose enhancement in the target of interest.


Assuntos
Ouro/química , Nanopartículas Metálicas/química , Dosagem Radioterapêutica , Núcleo Celular/patologia , Núcleo Celular/efeitos da radiação , Humanos , Método de Monte Carlo , Neoplasias/patologia , Neoplasias/radioterapia , Fótons
15.
Cancer Radiother ; 23(5): 416-422, 2019 Sep.
Artigo em Francês | MEDLINE | ID: mdl-31421998

RESUMO

This article provides a proposal for the selection and delineation of clinical target volumes for the treatment with radiation of submandibular glands tumours. This article does not deal with external radiotherapy indications but specifies the volumes to be treated if radiotherapy is chosen. High-risk and low-risk peritumoral clinical target volumes are described based on the probability of local tumoral spread. High-risk and low-risk clinical target volumes are illustrated on CT-scan slices. A proposal for the selection of nodal clinical target volumeis also proposed.


Assuntos
Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias da Glândula Submandibular/radioterapia , Humanos , Irradiação Linfática/métodos , Imagem por Ressonância Magnética , Invasividade Neoplásica , Tamanho do Órgão , Dosagem Radioterapêutica , Risco , Neoplasias da Glândula Submandibular/diagnóstico por imagem , Neoplasias da Glândula Submandibular/patologia , Tomografia Computadorizada por Raios X , Carga Tumoral
16.
Medicine (Baltimore) ; 98(31): e16673, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31374045

RESUMO

The aim of this study was to analyze dose-volume histogram (DVH) of the remnant liver for postoperative cholangiocarcinoma (CCA) patients, to find toxicity rates, and to confirm efficacy of postoperative radiation therapy (RT).Thirty-two postoperative CCA patients received partial liver resection and postoperative RT with curative intent. The "liver reduction rate" was calculated by contouring liver volume at computed tomography (CT) just before the surgery and at CT for planning the RT. To evaluate late toxicity, the radiation-induced hepatic toxicity (RIHT) was determined by the common terminology criteria for adverse events toxicity grade of bilirubin, aspartate transaminase, alanine transaminase, alkaline phosphatase, and albumin, and was defined from 3 months after RT until liver metastasis was revealed. The radiation-induced liver disease (RILD) was also evaluated.Tumor stages were distributed as follows: I: 1, II: 8, IIIA: 1, IIIB: 6, IIIC: 14, IVA: 2. Median prescribed total dose was 50 Gy. Median follow-up time was 27 months. Two-year overall survival (OS): 72.4%, disease-free survival: 47.7%, local control: 65.3%, and the median survival time was 40 months. The median "liver reduction rate" was 21%. The OS had statistically significant difference in nodal status (P = .032) and "liver reduction rate" >30% (P = .016). In the association between the ≥grade 2 RIHT and DVH, there were significantly differences in V30 and V40 (P = .041, P = .034), respectively. The grade ≥2 RIHT rates differ also significantly by sex (P = .008). Two patients (6.2%) were suspected of RILD.We suggest that RT for remnant liver should be considered the liver V30, V40 to prevent radiation-induced liver dysfunction.


Assuntos
Colangiocarcinoma/radioterapia , Hepatopatias/prevenção & controle , Neoplasias Hepáticas/radioterapia , Lesões por Radiação/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/patologia , Colangiocarcinoma/cirurgia , Cisplatino/uso terapêutico , Terapia Combinada , Desoxicitidina/análogos & derivados , Desoxicitidina/uso terapêutico , Combinação de Medicamentos , Hepatectomia , Humanos , Estimativa de Kaplan-Meier , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Ácido Oxônico/uso terapêutico , Piridinas/uso terapêutico , Radiossensibilizantes/uso terapêutico , Dosagem Radioterapêutica , Radioterapia Adjuvante , Tegafur/uso terapêutico , Tomografia Computadorizada por Raios X
18.
Anticancer Res ; 39(8): 4237-4242, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31366511

RESUMO

AIM: To define safety and efficacy of a palliative, short-course accelerated radiation therapy for symptomatic locally advanced primary pelvic cancer. MATERIALS AND METHODS: A phase II trial was planned based on the minimax Simon's two-stage design. A total of 18 Gy in 4.5 Gy/fraction administered twice a day was delivered (SHARON). Pain and quality of life were recorded according to the Visual Analogue self-assessment and the cancer linear analog scales (CLAS), respectively. RESULTS: Twenty-five patients were enrolled in the study. The most frequent baseline symptoms were pain (48%), bleeding (40%), bleeding/pain (8%), and intestinal sub-occlusion (4%). The overall palliative response rate was 96.0%, with a median palliative duration of 6 months. An improvement of quality-of-life indices (well-being, fatigue, and ability to perform daily activities) was noted in 64.0%, 36.0%, and 48.0% of patients, respectively. CONCLUSION: The SHARON regimen was well tolerated and effective in the palliative treatment of patients with locally advanced pelvic cancer. Based on these results, a multicentric prospective phase III trial is ongoing to compare this regimen with traditional 2-week radiotherapy treatment.


Assuntos
Cuidados Paliativos , Neoplasias Pélvicas/radioterapia , Lesões por Radiação/patologia , Radioterapia/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Fracionamento da Dose de Radiação , Feminino , Humanos , Masculino , Dose Máxima Tolerável , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Pélvicas/patologia , Pelve/patologia , Pelve/efeitos da radiação , Qualidade de Vida , Dosagem Radioterapêutica
19.
Artigo em Japonês | MEDLINE | ID: mdl-31434844

RESUMO

Commissioning of a linear accelerator (Linac) and treatment planning systems (RTPs) for clinical use is complex and time-consuming, typically 3-4 months in total. However, based on clinical needs and economics, hospitals desire early clinical starts for patients, and various studies have been conducted for shortening the preparation period. One of the methods to shorten the period is using golden beam data (GBD). The purpose of this study was to shorten the commissioning period without reducing accuracy and to simplify commissioning works while improving safety. We conducted commissioning of the RTPs before installing the Linac using GBD, and carried out verification immediately after the acceptance test. We used TrueBeam STx (Varian Medical Systems) and Eclipse (ver. 13.7, Varian Medical Systems) for RTPs and anisotropic analysis algorithm (AAA) and AcurosXB (AXB) for calculation algorithms. The difference between GBD and the measured beam data was 0.0 ± 0.2% [percentage depth dose (PDDs) ] and -0.1 ± 0.2% (Profiles) with X-ray, and -1.2 ± 1.3% (PDDs) with electrons. The difference between the calculated dose and the measured dose was 0.1 ± 0.3% (AAA) and 0.0 ± 0.3% (AXB) under homogeneous conditions, and 0.7 ± 1.4% (AAA) and 0.6 ± 1.1% (AXB) under heterogeneous conditions. We took 43 days from the end of the acceptance test to the start of clinical use. We found that the preparation period for clinical use can be shortened without reducing the accuracy, by thinning out the number of measurement items using GBD.


Assuntos
Aceleradores de Partículas , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Algoritmos , Elétrons , Humanos , Método de Monte Carlo , Dosagem Radioterapêutica
20.
Artigo em Japonês | MEDLINE | ID: mdl-31434847

RESUMO

The purpose of this study was to evaluate the discrepancy between the monitor unit (MU) calculated by different dose normalization methods in the electron Monte Carlo (eMC) algorithm and the conventional manual MU. In the water phantom condition, the manual MU obtained from the measured output factor was compared with the calculated MU by the eMC algorithm, using 24 different irradiation field shapes and several different energies of electron beam. In the breast boost condition, calculated MUs by both calculation methods were evaluated for 45 cases. As a result, the MUs computed by the eMC algorithm in the water phantom varied according to the dose normalization methods, and the mean±standard deviation of the difference between the manual and calculated MU were 1.1±1.4%, 0.0±1.0% and 0.4±1.2% in peak depth normalization (PN), no plan normalization (NPN) and 100% at body maximum (100%BM), respectively. In breast-boost cases, the MU difference between the manual and the calculated MU were 6.1±3.7%, 3.4±2.8% and 1.1±2.9% in PN, NPN and 100%BM, respectively. We revealed that the resultant MU calculated by eMC algorithm was dependent on the dose normalization method and the averaged differences exceeded 6% in PN, especially in breast boost condition. When using the eMC in the breast boost condition, it is desirable to select an appropriate dose normalization method according to dose prescription policies at each facility.


Assuntos
Elétrons , Método de Monte Carlo , Planejamento da Radioterapia Assistida por Computador , Algoritmos , Imagens de Fantasmas , Dosagem Radioterapêutica
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