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1.
Med Oral Patol Oral Cir Bucal ; 26(4): e466-e473, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33340073

RESUMO

BACKGROUND: Incidence of Medication-Related Osteonecrosis of the Jaw (MRONJ) related to cancer and myeloma treatments is undetermined, with scarce data varying from 2 to 7.8/million/year in limited investigated populations. A 9-years [2009-2018] regional-wide survey was conducted, deploying the North-Western Italy Cancer Network ("Rete Oncologica Piemonte e Valle d'Aosta"), to assess number and main characteristics of MRONJ cases among myeloma/cancer patients, within a population of 4.5 million inhabitants. MATERIAL AND METHODS: MRONJ cases were collected retrospectively from January 2009 to June 2015; from July 2015 to December 2018, data were collected prospectively. Number of new MRONJ cases per year, underlying disorder, drug(s) administered, treatment duration, site and onset timing of MRONJ were detailed. RESULTS: 459 MRONJ cases were identified. Primary diseases were breast cancer (46%), prostate cancer (21%), myeloma (19%), and other types of carcinoma (14%). Patients received antiresorptive treatment either alone (399; 88.47%) or in combination with biological agents (52; 11.53%); 8 patients (1.7%) received only antiangiogenic drugs. Zoledronic acid [388] and denosumab [59] were the most frequently administered drugs. Mandible was involved in 296 (64,5%) cases. Number of new MRONJ cases was stable from 2009 to 2015, with a mean of 51.3 cases per year (raw incidence: 11.6/million/year), declining in the 2016-2018 years to 33.3 cases per year (raw incidence: 7.5/million/year). CONCLUSIONS: With such discrepancy of cases overtime being partially explicable, number of new MRONJ cases per year are consistent with those observed in a previous study [2003-2008] in the same region, being instead higher than those reported in other populations.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Mieloma Múltiplo , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/epidemiologia , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Conservadores da Densidade Óssea/efeitos adversos , Difosfonatos , Humanos , Itália/epidemiologia , Masculino , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/epidemiologia , Estudos Retrospectivos
2.
Sci Rep ; 10(1): 22145, 2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33335162

RESUMO

This paper presents a physical frequency-diverse multimode lens-loaded cavity, designed and used for the purpose of the direction of arrival (DoA) estimation in millimetre-wave frequency bands for 5G and beyond. The multi-mode mechanism is realized using an electrically-large cavity, generating spatio-temporally incoherent radiation masks leveraging the frequency-diversity principle. It has been shown for the first time that by placing a spherical constant dielectric lens (constant-ϵr) in front of the radiating aperture of the cavity, the spatial incoherence of the radiation modes can be enhanced. The lens-loaded cavity requires only a single lens and output port, making the hardware development much simpler and cost-effective compared to conventional DoA estimators where multiple antennas and receivers are classically required. Using the lens-loaded architecture, an increase of up to 6 dB is achieved in the peak gain of the synthesized quasi-random sampling bases from the frequency-diverse cavity. Despite the fact that the practical frequency-diverse cavity uses a limited subset of quasi-orthogonal modes below the upper bound limit of the number of theoretical modes, it is shown that the proposed lens-loaded cavity is capable of accurate DoA estimation. This is achieved thanks to the sufficient orthogonality of the leveraged modes and to the presence of the spherical constant-ϵr lens which increases the signal-to-noise ratio (SNR) of the received signal. Experimental results are shown to verify the proposed approach.

3.
Eur Rev Med Pharmacol Sci ; 24(14): 7589-7597, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32744685

RESUMO

OBJECTIVE: This review aimed at examining efficacy of interventional radiotherapy (brachytherapy-IRT) alone or combined with external beam radiotherapy (EBRT) in stage I esophageal cancer as exclusive treatment. MATERIALS AND METHODS: A systematic research using PubMed, Scopus, and Cochrane library was performed. ClinicalTrials.gov was searched for ongoing or recently completed trials, and PROSPERO was searched for ongoing or recently completed systematic reviews. We analyzed only clinical study as full-text publication, reporting on patients with stage I esophageal cancer treated with IRT alone or in combination with other treatments (e.g., EBRT). Conference paper, survey, letter, editorial, book chapter, and review were excluded. Patients who underwent previous surgery were excluded. Time restriction (1990-2018) was applied for years of the publication. RESULTS: Twelve studies have been selected. The number of evaluated patients was 514; the median age was 69 years. In the IRT group, the median: local control (LC) was 77% (range 63%-100%), disease-free survival (DFS) was 68.4% (range 49%-86.3%), the overall survival (OS) was 60% (range 31%-84%), the cancer specific survival (CSS) was 80% (range 55-100%), and grade 3-4 toxicity range was 0%-26%. CONCLUSIONS: IRT alone or combined to EBRT is an effective and safe treatment option for patients with stage I esophageal cancer. Definitive radiation therapy could be an alternative to surgery in patients with superficial cancer.


Assuntos
Braquiterapia , Neoplasias Esofágicas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Braquiterapia/efeitos adversos , Braquiterapia/mortalidade , Intervalo Livre de Doença , Neoplasias Esofágicas/mortalidade , Neoplasias Esofágicas/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias
4.
Oral Dis ; 23(4): 477-483, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28039941

RESUMO

OBJECTIVES: Osteonecrosis of the jaw (ONJ) is a potentially severe adverse effect of bisphosphonates (BP). Although the risk of ONJ increases with increasing duration of BP treatment, there are currently no reliable estimates of the ONJ time to onset (TTO). The objective of this study was to estimate the TTO and associated risk factors in BP-treated patients. SUBJECTS AND METHODS: Retrospective analysis of data from 22 secondary care centres in seven countries relevant to 349 patients who developed BP-related ONJ between 2004 and 2012. RESULTS: The median (95%CI) TTO was 6.0 years in patients treated with alendronate (n = 88) and 2.2 years in those treated with zoledronate (n = 218). Multivariable Cox regression showed that dentoalveolar surgery was inversely associated, and the use of antiangiogenics directly associated, with the TTO in patients with cancer treated with zoledronate. CONCLUSIONS: The incidence of ONJ increases with the duration of BP therapy, with notable differences observed with respect to BP type and potency, route of administration and underlying disease. When data are stratified by BP type, a time of 6.0 and 2.2 years of oral alendronate and intravenous zoledronate therapy, respectively, is required for 50% of patients to develop ONJ. After stratification by disease, a time of 5.3 and 2.2 years of BP therapy is required for 50% of patients with osteoporosis and cancer, respectively, to develop ONJ. These findings have significant implications for the design of future clinical studies and the development of risk-reduction strategies aimed at either assessing or modulating the risk of ONJ associated with BP.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/etiologia , Conservadores da Densidade Óssea/administração & dosagem , Difosfonatos/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/epidemiologia , Conservadores da Densidade Óssea/efeitos adversos , Estudos Transversais , Difosfonatos/efeitos adversos , Esquema de Medicação , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
6.
Clin. transl. oncol. (Print) ; 16(5): 503-508, mayo 2014. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127892

RESUMO

PURPOSE: To evaluate radiotherapy treatment planning accuracy by varying computed tomography (CT) slice thickness and tumor size. METHODS: CT datasets from patients with primary brain disease and metastatic brain disease were selected. Tumor volumes ranging from about 2.5 to 100 cc and CT scan at different slice thicknesses (1, 2, 4, 6 and 10 mm) were used to perform treatment planning (1-, 2-, 4-, 6- and 10-CT, respectively). For any slice thickness, a conformity index (CI) referring to 100, 98, 95 and 90 % isodoses and tumor size was computed. All the CI and volumes obtained were compared to evaluate the impact of CT slice thickness on treatment plans. RESULTS: The smallest volumes reduce significantly if defined on 1-CT with respect to 4- and 6-CT, while the CT slice thickness does not affect target definition for the largest volumes. The mean CI for all the considered isodoses and CT slice thickness shows no statistical differences when 1-CT is compared to 2-CT. Comparing the mean CI of 1- with 4-CT and 1- with 6-CT, statistical differences appear only for the smallest volumes with respect to 100, 98 and 95 % isodoses-the CI for 90 % isodose being not statistically significant for all the considered PTVs. CONCLUSIONS: The accuracy of radiotherapy tumor volume definition depends on CT slice thickness. To achieve a better tumor definition and dose coverage, 1- and 2-CT would be suitable for small targets, while 4- and 6-CT are suitable for the other volumes (AU)


No disponible


Assuntos
Humanos , Masculino , Feminino , Tomógrafos Computadorizados/tendências , Tomógrafos Computadorizados , Neoplasias/diagnóstico , Sobrevivência/psicologia , Encefalopatias
7.
Cancer Invest ; 32(3): 85-91, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24499109

RESUMO

PURPOSE: To explore a novel patient-dose DVH-based method for pretreatment dose quality assurance tests. METHODS: 20 IMRT plans for head-and-neck cancer patients were used. A comparison was performed between the planned dose distributions, the computed, and the reconstructed ones using the gamma-index (GI) method. The GI analysis was performed using both the 3%/3 mm and the 2%/2 mm criteria. RESULTS: No significant DVH-deviation was observed. Considering the 3%/3 mm criteria the mean GI% < 1 for the body and structures was significantly higher compared to 2%/2 mm criteria. CONCLUSIONS: Our results underline the importance of QA-methods based on DVH-metrics to predict the impact of delivered dose.


Assuntos
Garantia da Qualidade dos Cuidados de Saúde , Planejamento da Radioterapia Assistida por Computador/normas , Radioterapia de Intensidade Modulada/normas , Raios gama , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos
8.
Phys Med ; 30(4): 462-72, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24480527

RESUMO

The aim of this paper is to evaluate clinically relevant quality assurance (QA) tests for RapidArc prostate patients. 26 plans were verified by the COMPASS system that provides an independent angle response and a reconstruction of dose distribution in patient CT model. Plan data were imported from treatment planning system via DICOM. The fluencies, measured by a 2D detector, were used by COMPASS to forward calculate dose in CT patients and reconstruct dose-volume-histogram (DVH). The gamma analysis was performed, using both the criteria 3%-3-mm and 2%-2 mm, for the whole grid patient and the per-structure volume. A DVH-based analysis was accomplished for target and organs-at-risk (OAR). The correlation between gamma passing rates and DVH discrepancies was performed using Pearson's test. Sensitivity, specificity and accuracy of whole and per-structure gamma method were calculated. No significant DVH deviation was observed for target and OAR. Weak correlation between gamma passing rates and dosimetric deviations was observed, all significant r-values were negative. The whole gamma method shows lack of sensitivity to detect dosimetric deviations >5%. Instead, a better balance between sensitivity and specificity was obtained employing per structure gamma both with 3%-3 mm and 2%-2 mm criteria. Because of the poor correlation between DVH goals and gamma passing rates, we encourage the DVH-based gamma passing rates, when it is possible. At least, a gamma method specific for structure was strongly suggested.


Assuntos
Neoplasias da Próstata/radioterapia , Garantia da Qualidade dos Cuidados de Saúde , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Humanos , Masculino , Órgãos em Risco/efeitos da radiação , Radiometria , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos
9.
Clin. transl. oncol. (Print) ; 16(2): 141-146, feb. 2014. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127716

RESUMO

PURPOSE: To evaluate the impact of different machines on plan quality using both intensity modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) techniques. MATERIALS AND METHODS: Eight patients with squamous cell carcinoma of the oropharynx were selected at random. Plans were computed for IMRT and VMAT Smart Arc, using Pinnacle TPS for an Elekta (IMRT-E, VMAT-E) and Varian linac (IMRT-V, VMAT-V). A three-dose level prescription was used to deliver 70, 63 and 58.1 Gy to regions of macroscopic, microscopic high- and low-risk disease, respectively. All doses were given in 35 fractions. Comparisons were performed on dose-volume histogram data, monitor units (MU), and delivery time. RESULTS: VMAT-E plans resulted slightly MU efficient (-24 % p < 0.05) compared to VMAT-V while IMRT-V shortened delivery time (-19 % p < 0.05) compared to IMRT-E. All the delivery techniques resulted in equivalent target coverage in terms of D(98) % and D(2) %. For VMAT technique, a significant improvement of 7 % in homogeneity index (HI) for PTV58.1 was observed for Varian machine. A slight improvement in OARs sparing was observed with Elekta machine both for IMRT and VMAT techniques. CONCLUSION: Similar plan quality was observed for Elekta and Varian linacs, significant differences were observed in delivery efficiency, as MU number and delivery times, in favor of Elekta and Varian, respectively (AU)


No disponible


Assuntos
Humanos , Aceleradores de Partículas/normas , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/normas , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/normas , Carcinoma de Células Escamosas/radioterapia , Desenho de Equipamento , Tratamentos com Preservação do Órgão , Órgãos em Risco , Neoplasias Orofaríngeas/radioterapia , Controle de Qualidade , Radioterapia Guiada por Imagem/instrumentação , Radioterapia Guiada por Imagem/normas
10.
Clin. transl. oncol. (Print) ; 16(2): 208-212, feb. 2014. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127726

RESUMO

INTRODUCTION: To evaluate the delivery accuracy of dynamic (DMLC) and static (SMLC) intensity modulated radiation therapy (IMRT) techniques using portal dosimetry (PD) in Varian Eclipse Treatment Planning System. MATERIALS AND METHODS: Seven DMLC IMRT Head and Neck plans were retrospectively generated for the study using SMLC mode at 20, 10 and 5 levels of intensity (SMLC20, SMLC10, SMLC5). Dosimetric verifications performed by PD on a total of 107 fields were evaluated using the gamma index (maximum (γmax), average (γavg), percentage of points with (γ%) ≤ 1). The images were acquired at a source-detector distance of 100 cm at gantry zero degree and also at clinically planned gantry angles. RESULTS: For both modes, measurements are within acceptable criteria. (γ%) ≤ 1 improves by increasing SMLC levels (+3.4 % from SMLC5 to SMLC20, p < 0.001) and using DMLC (+3.9 % and +0.6 % compared to SMLC5 and SMLC20, respectively, p < 0.001). Also (γmax) parameter improves significantly by increasing SMLC levels (+22 % from SMLC5 to SMLC20) and using DMLC (+34 % and +16 % compared to SMLC5 and SMLC20, respectively). The effect of the gantry rotation influences the delivery accuracy by up to -7 % (p < 0.05). The effect of leaves travelling direction was almost negligible (1 %). CONCLUSIONS: A good agreement between calculated and measured fluences was obtained for DMLC and SMLC techniques at higher intensity levels; however, DMLC delivery ensures the best reproduction of computed fluence maps. The gantry rotation influences the delivery accuracy in particular for SMLC modes at lower intensity levels (AU)


No disponible


Assuntos
Humanos , Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/instrumentação , Radioterapia Guiada por Imagem/métodos , Radioterapia Guiada por Imagem/normas , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/métodos , Órgãos em Risco , Sensibilidade e Especificidade , Estudos Retrospectivos
11.
Clin Transl Oncol ; 16(2): 141-6, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23645162

RESUMO

PURPOSE: To evaluate the impact of different machines on plan quality using both intensity modulated radiation therapy (IMRT) and volumetric-modulated arc therapy (VMAT) techniques. MATERIALS AND METHODS: Eight patients with squamous cell carcinoma of the oropharynx were selected at random. Plans were computed for IMRT and VMAT Smart Arc, using Pinnacle TPS for an Elekta (IMRT-E, VMAT-E) and Varian linac (IMRT-V, VMAT-V). A three-dose level prescription was used to deliver 70, 63 and 58.1 Gy to regions of macroscopic, microscopic high- and low-risk disease, respectively. All doses were given in 35 fractions. Comparisons were performed on dose-volume histogram data, monitor units (MU), and delivery time. RESULTS: VMAT-E plans resulted slightly MU efficient (-24 % p < 0.05) compared to VMAT-V while IMRT-V shortened delivery time (-19 % p < 0.05) compared to IMRT-E. All the delivery techniques resulted in equivalent target coverage in terms of D(98) % and D(2) %. For VMAT technique, a significant improvement of 7 % in homogeneity index (HI) for PTV58.1 was observed for Varian machine. A slight improvement in OARs sparing was observed with Elekta machine both for IMRT and VMAT techniques. CONCLUSION: Similar plan quality was observed for Elekta and Varian linacs, significant differences were observed in delivery efficiency, as MU number and delivery times, in favor of Elekta and Varian, respectively.


Assuntos
Aceleradores de Partículas/normas , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/normas , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/normas , Carcinoma de Células Escamosas/radioterapia , Desenho de Equipamento , Humanos , Tratamentos com Preservação do Órgão , Órgãos em Risco , Neoplasias Orofaríngeas/radioterapia , Controle de Qualidade , Dosagem Radioterapêutica , Radioterapia Guiada por Imagem/instrumentação , Radioterapia Guiada por Imagem/normas
12.
Clin Transl Oncol ; 16(2): 208-12, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23793811

RESUMO

INTRODUCTION: To evaluate the delivery accuracy of dynamic (DMLC) and static (SMLC) intensity modulated radiation therapy (IMRT) techniques using portal dosimetry (PD) in Varian Eclipse Treatment Planning System. MATERIALS AND METHODS: Seven DMLC IMRT Head and Neck plans were retrospectively generated for the study using SMLC mode at 20, 10 and 5 levels of intensity (SMLC20, SMLC10, SMLC5). Dosimetric verifications performed by PD on a total of 107 fields were evaluated using the gamma index (maximum (γmax), average (γavg), percentage of points with (γ%) ≤ 1). The images were acquired at a source-detector distance of 100 cm at gantry zero degree and also at clinically planned gantry angles. RESULTS: For both modes, measurements are within acceptable criteria. (γ%) ≤ 1 improves by increasing SMLC levels (+3.4 % from SMLC5 to SMLC20, p < 0.001) and using DMLC (+3.9 % and +0.6 % compared to SMLC5 and SMLC20, respectively, p < 0.001). Also (γmax) parameter improves significantly by increasing SMLC levels (+22 % from SMLC5 to SMLC20) and using DMLC (+34 % and +16 % compared to SMLC5 and SMLC20, respectively). The effect of the gantry rotation influences the delivery accuracy by up to -7 % (p < 0.05). The effect of leaves travelling direction was almost negligible (1 %). CONCLUSIONS: A good agreement between calculated and measured fluences was obtained for DMLC and SMLC techniques at higher intensity levels; however, DMLC delivery ensures the best reproduction of computed fluence maps. The gantry rotation influences the delivery accuracy in particular for SMLC modes at lower intensity levels.


Assuntos
Radiometria/métodos , Planejamento da Radioterapia Assistida por Computador , Radioterapia Guiada por Imagem , Radioterapia de Intensidade Modulada , Humanos , Órgãos em Risco , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/instrumentação , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Guiada por Imagem/instrumentação , Radioterapia Guiada por Imagem/métodos , Radioterapia Guiada por Imagem/normas , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/métodos , Estudos Retrospectivos , Sensibilidade e Especificidade
13.
Clin Transl Oncol ; 16(5): 503-8, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24052169

RESUMO

PURPOSE: To evaluate radiotherapy treatment planning accuracy by varying computed tomography (CT) slice thickness and tumor size. METHODS: CT datasets from patients with primary brain disease and metastatic brain disease were selected. Tumor volumes ranging from about 2.5 to 100 cc and CT scan at different slice thicknesses (1, 2, 4, 6 and 10 mm) were used to perform treatment planning (1-, 2-, 4-, 6- and 10-CT, respectively). For any slice thickness, a conformity index (CI) referring to 100, 98, 95 and 90 % isodoses and tumor size was computed. All the CI and volumes obtained were compared to evaluate the impact of CT slice thickness on treatment plans. RESULTS: The smallest volumes reduce significantly if defined on 1-CT with respect to 4- and 6-CT, while the CT slice thickness does not affect target definition for the largest volumes. The mean CI for all the considered isodoses and CT slice thickness shows no statistical differences when 1-CT is compared to 2-CT. Comparing the mean CI of 1- with 4-CT and 1- with 6-CT, statistical differences appear only for the smallest volumes with respect to 100, 98 and 95 % isodoses-the CI for 90 % isodose being not statistically significant for all the considered PTVs. CONCLUSIONS: The accuracy of radiotherapy tumor volume definition depends on CT slice thickness. To achieve a better tumor definition and dose coverage, 1- and 2-CT would be suitable for small targets, while 4- and 6-CT are suitable for the other volumes.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Radioterapia de Intensidade Modulada , Tomografia Computadorizada por Raios X/métodos , Carga Tumoral , Neoplasias Encefálicas/patologia , Humanos
14.
Technol Cancer Res Treat ; 13(4): 325-35, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24206203

RESUMO

Due to the anatomical changes frequently occurring during the course of head and neck (H&N) cancer radiotherapy, the dose distribution, which was actually delivered to the patient, might significantly differ from that planned. The aim of this paper is to investigate these volumetric changes and the resulting dosimetric implications on organs at risk (OARs) and clinical target volumes (CTVs) by cone beam computed tomography (CBCT) scans throughout the treatment. Ten H&N patients, treated by Intensity Modulated Radiotherapy, were analyzed. CTVs and OARs were delineated on four CBCT, acquired at the 10(th), 15(th), 20(th) and 25(th) treatment session, and then compared with the ones at planning CT. The planned beams were applied to each CBCT to recalculate the dose distribution and the corresponding dose volume histograms were compared with those generated on planning CT. To evaluate the HU discrepancies between the conventional CT and CBCT images we used a Catphan(r) 504, observing a maximum discrepancy of about 30 HU. We evaluated the impact of this HU difference in dose calculation and a not clinically relevant error, within 2.8%, was estimated. No inhomogeneity correction was used. The results showed an increased CTV mean dose (Dmean) of about 3% was found, without significant reduction in volume. Due to the parotids' shrinkage (up to 42%), significant dosimetric increases were observed: ipsilateral gland at 15th CBCT (Dmean by 18%; V30 by 31%); controlateral gland at the 10(th) CBCT (Dmean by 12.2%; V30 by 18.7%). For the larynx, a significant increase of volume was found at the 20th (15.7%) and 25th CBCT (13.3%) but it complied with dose constraint. The differences observed for the spinal cord and mandible maximum doses were not clinically relevant. In conclusion, the dosimetric analysis on CBCT can help clinicians to monitor treatment progress and to evaluate whether and when a new plan is necessary. The main benefit of replanning could be to preserve the parotids and our data support the hypothesis that the 3rd week of radiotherapy should be a check point for parotids.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/radioterapia , Radiometria , Planejamento da Radioterapia Assistida por Computador , Adulto , Tomografia Computadorizada de Feixe Cônico , Humanos , Estadiamento de Neoplasias , Dosagem Radioterapêutica , Fatores de Tempo , Resultado do Tratamento , Carga Tumoral , Redução de Peso
15.
Clin. transl. oncol. (Print) ; 15(10): 861-864, oct. 2013. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127512

RESUMO

OBJECTIVES: To investigate the effect of external beam radiotherapy (EBRT) for head and neck cancer (HNC) the intimal-medial thickness (IMT) and the lumen of the carotid artery. METHODS: Patients with HNC and an indication for EBRT were enrolled. A carotid artery color Doppler examination was performed before and 6 and 12 months after EBRT. RESULTS: From 2008 to 2011, 50 patients were enrolled. The mean carotid IMT was 0.9 vs. 1.02 mm before and 6 months after EBRT, respectively (p = 0.0001). The common carotid artery lumen was narrowed without statistical significance, 6 months after EBRT (p = 0.3). 1 year from EBRT, the IMT increase and the lumen reduction were statistically significant (p = 0.001, p = 0.01, respectively). Neurological events (stroke or TIA) were not observed. CONCLUSIONS: Our data showed a significant IMT increase 6 months from EBRT without a corresponding narrowing of the common carotid lumen while a significant increase 12 months after EBRT (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Artérias Carótidas/efeitos da radiação , Doenças das Artérias Carótidas/etiologia , Espessura Intima-Media Carotídea , Neoplasias de Cabeça e Pescoço/radioterapia , Lesões por Radiação/etiologia , Lesões por Radiação , Túnica Média/efeitos da radiação , Artérias Carótidas/patologia , Artérias Carótidas , Doenças das Artérias Carótidas , Estadiamento de Neoplasias , Seguimentos , Estudos Observacionais como Assunto , Prognóstico , Túnica Média , Fatores de Risco
16.
Clin. transl. oncol. (Print) ; 15(9): 754-758, sept. 2013. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127496

RESUMO

PURPOSE: To assess the differences between the target delineation using computed tomography (CT) and imaging fusion CT/magnetic resonance imaging (MRI) for the radiotherapy planning of glioblastoma. METHODS: One hundred-twenty gross tumor volume and clinical target volume on CT and MRI (GTVCT/CTVCT, GTVMRI/CTVMRI, respectively) were contoured and evaluated. The treatments planning (total dose 60 Gy) based on CTVCT were analysed in terms of percentage of CTVCT and CTVMRI receiving 95 % of the prescribed dose (V95-CTVCT, V95-CTVMRI). RESULTS: GTVs and CTVs contoured on MRI were significantly larger than those delineated on CT (p = 0.0003, p = 0.0006, respectively). Nighty-two percent of CTVCT was coincident with the CTVMRI and 8 % was normal tissue; 20 % of CTVMRI, considered as tumor volume, was not included on CTVCT. The V95-CTVMRI was significantly lower than the V95-CTVCT (p = 0.0005). CONCLUSIONS: In the delineation of glioblastoma target volume, fusion CT/MRI was preferred. The CT only is insufficient for the CTV dose coverage (AU)


Assuntos
Humanos , Masculino , Feminino , Glioblastoma/induzido quimicamente , Glioblastoma/metabolismo , Glioblastoma/radioterapia , Glioblastoma/classificação , Glioblastoma/diagnóstico , Tomógrafos Computadorizados/classificação , Espectroscopia de Ressonância Magnética
17.
Clin. transl. oncol. (Print) ; 15(8): 638-642, ago. 2013. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127480

RESUMO

PURPOSE: The major uncertainties in treating lung cancer are the repositioning errors and respiratory lung tumor motion. Typically, margins are added to the clinical target volume (CTV) to obtain a planning target volume (PTV) allowing the accommodation of such uncertainties. We want to test a new technique to assess the adequacy of the chosen PTV using an aSi electronic portal imaging device (EPID). METHODS: Four patients affected by lung cancer and treated by radical 3D conformal radiotherapy (3DRT) were studied. During treatment the EPID was used in cine mode acquisition: acquired images were used to the aim. RESULTS AND CONCLUSIONS: Treatment monitoring with an EPID in cine mode is shown to be a clinically feasible and useful tool (AU)


Assuntos
Humanos , Masculino , Feminino , Neoplasias Pulmonares/induzido quimicamente , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/secundário , Neoplasias/diagnóstico
18.
Clin. transl. oncol. (Print) ; 15(8): 665-669, ago. 2013. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127484

RESUMO

PURPOSE: To correlate comorbidity and acute radiation toxicity in elderly patients treated with adjuvant external beam radiotherapy (EBRT) plus brachytherapy-high dose rate (HDR-BRT) for endometrial cancer (EC). METHODS: Endometrial cancer patients over 65 were treated and evaluated for comorbidity assessment with ACE-27 and Charlson comorbidity index (CCI). EBRT total dose was 45-50.4 Gy (1.8 Gy/day). The vault vagina boost of dose was performed by HDR-BRT with 2/3 fractions with a total dose of 10-15 Gy. RESULTS: From 2008 to 2011, 35 patients were analyzed. Eighteen patients (51.43 %) had not ACE-27 comorbidity; while 27 patients (77.14 %) had CCI lower than three. During treatment, acute toxicity was mild and not influenced by the comorbidity score. Two-year Progression Free and Overall Survival were 69 and 80 %. ACE-27 and CCI did not affect progression-free survival (p = 0.51, p = 0.3) and OS (p = 0.26, p = 0.5). CONCLUSION: External beam radiotherapy plus BRT-HDR are well tolerated in EC elderly with good performance status and low comorbidity profile (AU)


Assuntos
Humanos , Masculino , Feminino , Idoso , Neoplasias do Endométrio/induzido quimicamente , Neoplasias do Endométrio/tratamento farmacológico , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/radioterapia , Neoplasias do Endométrio/diagnóstico , Neoplasias do Endométrio/mortalidade , Neoplasias do Endométrio/secundário
19.
Clin. transl. oncol. (Print) ; 15(5): 412-415, mayo 2013. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-127382

RESUMO

PURPOSE: To evaluate the dosimetric changes of parotid glands (PG) during a course of intensity-modulated radiotherapy (IMRT) in head and neck (H&N) cancer patients. METHODS: Ten patients with H&N cancer treated by IMRT were analyzed. The original treatment plan (CT(plan)) was transferred to cone-beam computed tomography (CBCT) acquired at the 15th and 20th treatment day (CBCT(plan) I and II, respectively). The PG mean dose (D(mean)), the dose to 50 % of the volume, and the percent of volume receiving 30 and 50 Gy were measured by the dose volume histogram. RESULTS: 30 IMRT plans were evaluated (3 plans/patient). All dosimetric end points increased significantly for both PG only when CT(plan) was compared to CBCT(plan) I. The D(mean) increased significantly only for ipsilateral PG (p = 0.02) at week 3. CONCLUSION: During a course of IMRT, CBCT is a feasible method to heck the PG dosimetric variations. Perhaps, the 3rd week of radiotherapy could be considered as the time-check-point (AU)


Assuntos
Humanos , Masculino , Feminino , Glândula Parótida/anormalidades , Glândula Parótida/metabolismo , Neoplasias de Cabeça e Pescoço/diagnóstico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia
20.
Clin Transl Oncol ; 15(10): 861-4, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23463595

RESUMO

OBJECTIVES: To investigate the effect of external beam radiotherapy (EBRT) for head and neck cancer (HNC) the intimal-medial thickness (IMT) and the lumen of the carotid artery. METHODS: Patients with HNC and an indication for EBRT were enrolled. A carotid artery color Doppler examination was performed before and 6 and 12 months after EBRT. RESULTS: From 2008 to 2011, 50 patients were enrolled. The mean carotid IMT was 0.9 vs. 1.02 mm before and 6 months after EBRT, respectively (p = 0.0001). The common carotid artery lumen was narrowed without statistical significance, 6 months after EBRT (p = 0.3). 1 year from EBRT, the IMT increase and the lumen reduction were statistically significant (p = 0.001, p = 0.01, respectively). Neurological events (stroke or TIA) were not observed. CONCLUSIONS: Our data showed a significant IMT increase 6 months from EBRT without a corresponding narrowing of the common carotid lumen while a significant increase 12 months after EBRT.


Assuntos
Artérias Carótidas/efeitos da radiação , Doenças das Artérias Carótidas/etiologia , Espessura Intima-Media Carotídea , Neoplasias de Cabeça e Pescoço/radioterapia , Lesões por Radiação/etiologia , Túnica Média/efeitos da radiação , Idoso , Idoso de 80 Anos ou mais , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Doenças das Artérias Carótidas/diagnóstico por imagem , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Observacionais como Assunto , Prognóstico , Lesões por Radiação/diagnóstico por imagem , Fatores de Risco , Túnica Média/diagnóstico por imagem , Ultrassonografia Doppler em Cores
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