Your browser doesn't support javascript.
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.530
Filtrar
1.
Br J Radiol ; 93(1107): 20190807, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32003574

RESUMO

After years of lethargy, studies on two non-conventional microstructures in time and space of the beams used in radiation therapy are enjoying a huge revival. The first effect called "FLASH" is based on very high dose-rate irradiation (pulse amplitude ≥106 Gy/s), short beam-on times (≤100 ms) and large single doses (≥10 Gy) as experimental parameters established so far to give biological and potential clinical effects. The second effect relies on the use of arrays of minibeams (e.g., 0.5-1 mm, spaced 1-3.5 mm). Both approaches have been shown to protect healthy tissues as an endpoint that must be clearly specified and could be combined with each other (e.g., minibeams under FLASH conditions). FLASH depends on the presence of oxygen and could proceed from the chemistry of peroxyradicals and a reduced incidence on DNA and membrane damage. Minibeams action could be based on abscopal effects, cell signalling and/or migration of cells between "valleys and hills" present in the non-uniform irradiation field as well as faster repair of vascular damage. Both effects are expected to maintain intact the tumour control probability and might even preserve antitumoural immunological reactions. FLASH in vivo experiments involving Zebrafish, mice, pig and cats have been done with electron beams, while minibeams are an intermediate approach between X-GRID and synchrotron X-ray microbeams radiation. Both have an excellent rationale to converge and be applied with proton beams, combining focusing properties and high dose rates in the beam path of pencil beams, and the inherent advantage of a controlled limited range. A first treatment with electron FLASH (cutaneous lymphoma) has recently been achieved, but clinical trials have neither been presented for FLASH with protons, nor under the minibeam conditions. Better understanding of physical, chemical and biological mechanisms of both effects is essential to optimize the technical developments and devise clinical trials.


Assuntos
Tratamentos com Preservação do Órgão/métodos , Terapia com Prótons/métodos , Animais , Gatos , Proliferação de Células , Dano ao DNA , Reparo do DNA , Fracionamento da Dose de Radiação , Linfoma Cutâneo de Células T/radioterapia , Camundongos , Órgãos em Risco/efeitos da radiação , Oxigênio , Consumo de Oxigênio , Lesões por Radiação/prevenção & controle , Tolerância a Radiação , Radiometria/métodos , Neoplasias Cutâneas/radioterapia , Análise Espaço-Temporal , Suínos , Peixe-Zebra
2.
Vasc Endovascular Surg ; 54(2): 172-174, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31714184

RESUMO

Axillary artery blowout is a rare life- and limb-threatening condition. The traditional surgical approach of ligation and extra-anatomic bypass is associated with a high morbidity and mortality. We present a case report of a 65-year-old male with axillary artery hemorrhage secondary to an irradiated squamous cell cancer. We propose a staged hybrid approach for the treatment of this unusual clinical entity consisting of emergent stent grafting followed by planned elective extra-anatomic bypass, debridement, and a course of specific antimicrobial therapy.


Assuntos
Artéria Axilar/efeitos da radiação , Artéria Axilar/cirurgia , Implante de Prótese Vascular , Carcinoma de Células Escamosas/radioterapia , Procedimentos Endovasculares , Hemorragia/cirurgia , Lesões por Radiação/terapia , Neoplasias Cutâneas/radioterapia , Idoso , Anti-Infecciosos/administração & dosagem , Prótese Vascular , Implante de Prótese Vascular/instrumentação , Carcinoma de Células Escamosas/patologia , Desbridamento , Procedimentos Endovasculares/instrumentação , Hemorragia/diagnóstico , Hemorragia/etiologia , Humanos , Masculino , Lesões por Radiação/diagnóstico , Lesões por Radiação/etiologia , Radioterapia Adjuvante/efeitos adversos , Neoplasias Cutâneas/patologia , Stents , Resultado do Tratamento
3.
Int J Radiat Oncol Biol Phys ; 106(3): 571-578, 2020 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-31759075

RESUMO

PURPOSE: Our purpose was to report the feasibility and safety of diffusing alpha-emitter radiation therapy (DaRT), which entails the interstitial implantation of a novel alpha-emitting brachytherapy source, for the treatment of locally advanced and recurrent squamous cancers of the skin and head and neck. METHODS AND MATERIALS: This prospective first-in-human, multicenter clinical study evaluated 31 lesions in 28 patients. The primary objective was to determine the feasibility and safety of this approach, and the secondary objectives were to evaluate the initial tumor response and local progression-free survival. Eligibility criteria included all patients with biopsy-proven squamous cancers of the skin and head and neck with either primary tumors or recurrent/previously treated disease by either surgery or prior external beam radiation therapy; 13 of 31 lesions (42%) had received prior radiation therapy. Toxicity was evaluated according to the Common Terminology Criteria for Adverse Events version 4.03. Tumor response was assessed at 30 to 45 days at a follow-up visit using the Response Evaluation Criteria in Solid Tumors, version 1.1. Median follow-up time was 6.7 months. RESULTS: Acute toxicity included mostly local pain and erythema at the implantation site followed by swelling and mild skin ulceration. For pain and grade 2 skin ulcerations, 90% of patients had resolution within 3 to 5 weeks. Complete response to the Ra-224 DaRT treatment was observed in 22 lesions (22/28; 78.6%); 6 lesions (6/28, 21.4%) manifested a partial response (>30% tumor reduction). Among the 22 lesions with a complete response, 5 (22%) developed a subsequent local relapse at the site of DaRT implantation at a median time of 4.9 months (range, 2.43-5.52 months). The 1-year local progression-free survival probability at the implanted site was 44% overall (confidence interval [CI], 20.3%-64.3%) and 60% (95% CI, 28.61%-81.35%) for complete responders. Overall survival rates at 12 months post-DaRT implantation were 75% (95% CI, 46.14%-89.99%) among all patients and 93% (95% CI, 59.08%-98.96%) among complete responders. CONCLUSIONS: Alpha-emitter brachytherapy using DaRT achieved significant tumor responses without grade 3 or higher toxicities observed. Longer follow-up observations and larger studies are underway to validate these findings.


Assuntos
Braquiterapia/métodos , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Recidiva Local de Neoplasia/radioterapia , Rádio (Elemento)/uso terapêutico , Neoplasias Cutâneas/radioterapia , Tório/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Partículas alfa/efeitos adversos , Partículas alfa/uso terapêutico , Braquiterapia/efeitos adversos , Braquiterapia/instrumentação , Carcinoma de Células Escamosas/patologia , Eritema/etiologia , Estudos de Viabilidade , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Dor Processual/etiologia , Fotografação , Projetos Piloto , Intervalo Livre de Progressão , Estudos Prospectivos , Rádio (Elemento)/efeitos adversos , Segurança , Neoplasias Cutâneas/patologia , Úlcera Cutânea/etiologia , Tório/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
4.
Surg Clin North Am ; 100(1): 189-199, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31753112

RESUMO

The role of radiation therapy in melanoma has evolved over the last few decades. There has been a dramatic improvement in radiation delivery with the introduction of intensity-modulated radiation therapy, image-guided radiation therapy, stereotactic radiosurgery, and stereotactic body radiation therapy/stereotactic radiation therapy. More recently, with the introduction of immunotherapy in various malignancies, including melanoma, the role of radiation therapy is being reevaluated. This article describes the evolution of the role of radiation therapy from nonimmunotherapy to the era of immunotherapy.


Assuntos
Melanoma/radioterapia , Neoplasias Cutâneas/radioterapia , Terapia Combinada , Humanos , Imunoterapia , Melanoma/terapia , Neoplasias Cutâneas/terapia
5.
Rev Med Chil ; 147(7): 928-931, 2019 Jul.
Artigo em Espanhol | MEDLINE | ID: mdl-31859992

RESUMO

Lhermitte phenomenon is a neurological symptom described as a sensation of electric shock that radiates from the back towards the extremities, which appears when a patient flexes the neck. A transient myelopathy as a late complication of radiotherapy is associated with this symptom. It appears two to four months after treatment and disappears spontaneously. We report a 45 years old female with a neck malignant melanoma treated with surgery and adjuvant radiotherapy. She experienced the Lhermitte phenomenon that was triggered by heat. This phenomenon must be differentiated from the Uhthoff phenomenon.


Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico , Temperatura Alta/efeitos adversos , Melanoma/diagnóstico , Dor/etiologia , Radioterapia Adjuvante/efeitos adversos , Neoplasias Cutâneas/diagnóstico , Diagnóstico Diferencial , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias de Cabeça e Pescoço/cirurgia , Humanos , Masculino , Melanoma/radioterapia , Melanoma/cirurgia , Pessoa de Meia-Idade , Neoplasias Cutâneas/radioterapia , Neoplasias Cutâneas/cirurgia
6.
Pan Afr Med J ; 33: 227, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31692791

RESUMO

Mycosis fungoid (MF) is a non-Hodgkin's T-cell lymphoma determined by primary cutaneous involvement. It is a slow-progressing chronic indolent disease characterized by atypical T-cells with a cerebral nucleus. Management of this disease depends on the stage and is based essentially on the systemic treatment. Radiotherapy intervenes in case of localized or extended tumor, indeed, the radiosensibility of this tumor, like any other hematological affection, makes it possible to obtain a high rate of response. Clinical case: we report the observation of a 46-year-old patient followed since 2012 for mycosis fungoid revealed by a papullo-squamous lesion located at the level of the right lumbar fossa. The diagnosis was confirmed by cutaneous biopsy, showing the presence of T lymphocytes expressing CD2, CD3, CD4, CCR4, CD45RO markers. Initial assessment included a thoraco-abdominal pelvic CT, which was normal, an accelerated sedimentation rate at the 1st hour, a high C reactive protein (CRP), the electrolytic, renal, hepatic status and the hemogram were normal. Patient received 6 courses of chemotherapy according to the COPP protocol with a decrease in the size of the lesion estimated at 40%. A norm fractionated radiation therapy was delivered at the dose of 36Gy. The evolution was marked by a complete remission, maintained after 6 months of the treatment. Mycosis fungoid is a rare disease, whose management must be discussed in a multidisciplinary team. Radiotherapy remains an interesting option for all stages, but has to be validated in largest studies.


Assuntos
Micose Fungoide/radioterapia , Neoplasias Cutâneas/radioterapia , Biópsia , Humanos , Pessoa de Meia-Idade , Micose Fungoide/diagnóstico , Neoplasias Cutâneas/diagnóstico , Linfócitos T/metabolismo
7.
Am Surg ; 85(10): 1118-1124, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31657306

RESUMO

Prospective randomized studies have demonstrated a survival benefit of immunotherapy in stage IV cutaneous melanoma. Some retrospective studies have hypothesized a synergistic effect of radiation and immunotherapy. Our objective was to identify whether there is a survival benefit for patients treated with radiation and immunotherapy in stage IV cutaneous melanoma of the head and neck (CMHN). The National Cancer Database was used to identify patients with stage IV CMHN between 2012 and 2014. These patients were stratified based on receipt of radiation and immunotherapy. Adjusted Cox regression was used to analyze overall survival. A total of 542 patients were identified with stage IV CMHN, of whom 153 (28%) patients received immunotherapy. Receipt of immunotherapy (hazard ratio [HR] 0.69, P = 0.02) and negative LNs (HR 0.50, P = 0.002) were independently associated with improved survival, whereas radiation conferred no survival benefit (HR 1.17, P = 0.26). Patients who received immunotherapy without radiation were associated with significantly improved survival compared with those who received immunotherapy with radiation (P < 0.0001). However, of patients who received radiation, the addition of immunotherapy did not seem to improve survival (P = 0.979). In stage IV CMHN, immunotherapy confers a 32 per cent survival benefit. The use of immunotherapy in patients who require radiation, however, is not associated with improved survival.


Assuntos
Antineoplásicos Imunológicos/uso terapêutico , Neoplasias de Cabeça e Pescoço/terapia , Imunoterapia/mortalidade , Ipilimumab/uso terapêutico , Melanoma/terapia , Neoplasias Cutâneas/terapia , Adulto , Idoso , Análise de Variância , Feminino , Neoplasias de Cabeça e Pescoço/mortalidade , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Imunoterapia/métodos , Linfonodos/patologia , Masculino , Melanoma/mortalidade , Melanoma/patologia , Melanoma/radioterapia , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Radioimunoterapia/métodos , Radioimunoterapia/mortalidade , Radioterapia/mortalidade , Estudos Retrospectivos , Neoplasias Cutâneas/mortalidade , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/radioterapia , Análise de Sobrevida , Fatores de Tempo
8.
Int J Radiat Biol ; 95(11): 1543-1546, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31550183

RESUMO

Introduction: In multi-well cell culture plates, wells are bordered by air cavities. The air cavity inhomogeneities can reduce the amount of delivered dose. In this study, the effect of these cavities on cell survival was investigated.Materials and methods: A special phantom was designed to house the plates and air cavities were filled by water equivalent materials. Cultured melanoma cells were irradiated using 6MV photon for 200 cGy. MTT and clonogenic assay tests were used to evaluate cell survival.Results: Results of MTT assay showed mean survival percentage for irradiated cells in the first group, i.e. plates with air cavities, was 18.9% higher than the second group with air cavities filled with paraffin. Clonogenic assay results showed a maximum of 37% difference in the mean of number of colonies between the first group and the second group (p value < .05).Conclusions: The presence of air cavities in multi-well cell culture plates reduced radiation cell kill by up to 37%. To ensure the accuracy of delivered dose, it is necessary to replace the air cavities as well as the air surrounding the plates by a water equivalent material.


Assuntos
Ar , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos da radiação , Melanoma/radioterapia , Neoplasias Cutâneas/radioterapia , Bioensaio , Linhagem Celular , Simulação por Computador , Raios gama , Humanos , Método de Monte Carlo , Imagens de Fantasmas , Fótons , Polimetil Metacrilato , Radiobiologia , Água
9.
Int J Mol Sci ; 20(18)2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31540513

RESUMO

Canine oral malignant melanoma (CoMM) is often treated by radiation therapy in veterinary medicine. However, not all cases are successfully managed by this treatment. For improved efficacy of radiation therapy, biomarkers predicting the radiosensitivity of melanoma cells need to be explored. Here, we, first, developed the radioresistant CoMM cell line, KMeC/R. We found that the expression level of phosphatase and tensin homolog (PTEN) of KMeC/R cells was significantly downregulated compared with KMeC cells. Overexpression of PTEN successfully restored the radiosensitivity of KMeC/R cells, and silencing of PTEN significantly increased the radioresistance of the CoMM cells tested. Next, we focused on microRNAs (miRNAs) to explore the mechanisms of downregulation of PTEN in KMeC/R cells. miR-374b was upregulated in KMeC/R cells compared with that in KMeC cells and in the irradiated CoMM cells tested. Furthermore, miR-374b directly targeted PTEN based on the luciferase activity assay. Moreover, the extrinsic miR-374b significantly increased the radioresistance of KMeC cells. In addition, the expression level of PTEN was significantly downregulated and that of miR-374b tended to be upregulated in recurrent CoMM tissues after radiation therapy compared with the pre-treatment tissues. Thus, the current study suggested that the miR-374b/PTEN signaling pathway possibly plays an important role in CoMM radiosensitivity.


Assuntos
Doenças do Cão/genética , Regulação Neoplásica da Expressão Gênica , Melanoma/veterinária , MicroRNAs/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias Cutâneas/veterinária , Animais , Linhagem Celular Tumoral , Doenças do Cão/radioterapia , Cães , Regulação para Baixo , Melanoma/genética , Melanoma/radioterapia , Tolerância a Radiação , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/radioterapia
10.
J Dermatol ; 46(10): 843-848, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31389056

RESUMO

Phakomatosis pigmentovascularis is a rare syndrome characterized by widespread capillary malformation and pigmented nevus. The objective of this study was to evaluate its characteristics and treatment. Fifty-two patients presenting between 2003 and 2017 were retrospectively reviewed. Type IIa (port-wine stain and dermal melanocytosis with oculocutaneous involvement) was most common. Systemic involvement was observed in 17.3% and it was not significantly correlated to extent of capillary malformation or pigmented nevus. However, systemic involvement was significantly frequent in patients with nevus of Ota and in patients with pigmented nevus located on the head and neck (P = 0.004 and 0.035, respectively). Capillary malformation was almost cleared in 28.6% of patients using pulsed dye laser, whereas pigmented nevus was almost cleared in 23.7% and completely cleared in 42.1% of patients using Q-switched neodymium:yttrium-aluminum-garnet laser. Treatment outcome score showed significant inverse correlation with the extent of port-wine stain or pigmented nevus (P = 0.047, ρ = -0.308 and P = 0.011, ρ = -0.410, respectively). Pigmented nevus demonstrated better treatment response to lasers than did capillary malformation. Smaller lesions tended to show better treatment outcomes for both capillary malformation and pigmented nevus.


Assuntos
Terapia com Luz de Baixa Intensidade/métodos , Síndromes Neurocutâneas/diagnóstico , Nevo de Ota/diagnóstico , Mancha Vinho do Porto/diagnóstico , Neoplasias Cutâneas/diagnóstico , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Lasers de Corante/uso terapêutico , Lasers de Estado Sólido/uso terapêutico , Terapia com Luz de Baixa Intensidade/instrumentação , Masculino , Pessoa de Meia-Idade , Síndromes Neurocutâneas/complicações , Síndromes Neurocutâneas/radioterapia , Nevo de Ota/etiologia , Nevo de Ota/radioterapia , Mancha Vinho do Porto/etiologia , Mancha Vinho do Porto/radioterapia , Estudos Retrospectivos , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/radioterapia , Resultado do Tratamento , Adulto Jovem
11.
J Appl Clin Med Phys ; 20(9): 78-85, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31454148

RESUMO

PURPOSE: This case series represents an initial experience with implementing 3-dimensional (3D) surface scanning, digital design, and 3D printing for bolus fabrication for patients with complex surface anatomy where traditional approaches are challenging. METHODS AND MATERIALS: For 10 patients requiring bolus in regions with complex contours, bolus was designed digitally from 3D surface scanning data or computed tomography (CT) images using either a treatment planning system or mesh editing software. Boluses were printed using a fused deposition modeling printer with polylactic acid. Quality assurance tests were performed for each printed bolus to verify density and shape. RESULTS: For 9 of 10 patients, digitally designed boluses were used for treatment with no issues. In 1 case, the bolus was not used because dosimetric requirements were met without the bolus. QA tests revealed that the bulk density was within 3% of the reference value for 9 of 12 prints, and with more judicious selection of print settings this could be increased. For these 9 prints, density uniformity was as good as or better than our traditional sheet bolus material. The average shape error of the pieces was less than 0.5 mm, and no issues with fit or comfort were encountered during use. CONCLUSIONS: This study demonstrates that new technologies such as 3D surface scanning, digital design and 3D printing can be safely and effectively used to modernize bolus fabrication.


Assuntos
Impressão Tridimensional/instrumentação , Garantia da Qualidade dos Cuidados de Saúde/normas , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/instrumentação , Radioterapia de Intensidade Modulada/métodos , Neoplasias Cutâneas/radioterapia , Idoso , Idoso de 80 Anos ou mais , Carcinoma Basocelular/diagnóstico por imagem , Carcinoma Basocelular/radioterapia , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/radioterapia , Desenho de Equipamento , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Órgãos em Risco/efeitos da radiação , Prognóstico , Dosagem Radioterapêutica , Neoplasias Cutâneas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos
13.
Cutis ; 103(5): 292-297;E1;E2;E3, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31233573

RESUMO

Although Mohs micrographic surgery (MMS) is the gold standard for treatment of nonmelanoma skin cancers (NMSCs), laser management has been an emerging treatment option that continues to be studied. Nonablative laser therapy is a noninvasive alternative. This study used a combined pulsed dye laser (PDL) and fractional laser approach to treat basal cell carcinomas (BCCs) in conjunction with noninvasive imaging such as reflectance confocal microscopy (RCM) and optical coherence tomography (OCT) to enhance efficacy rates.


Assuntos
Carcinoma Basocelular/radioterapia , Neoplasias Faciais/radioterapia , Lasers de Corante/uso terapêutico , Terapia com Luz de Baixa Intensidade , Recidiva Local de Neoplasia/diagnóstico por imagem , Neoplasias Cutâneas/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Basocelular/diagnóstico por imagem , Carcinoma Basocelular/patologia , Dermoscopia , Neoplasias Faciais/diagnóstico por imagem , Neoplasias Faciais/patologia , Humanos , Microscopia Confocal , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Neoplasia Residual , Estudos Retrospectivos , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Tomografia de Coerência Óptica , Resultado do Tratamento
14.
J Cancer Res Ther ; 15(3): 475-479, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31169207

RESUMO

Context: Low energy electron beam has been being used widely for superficial cancer treatments. In the current study a design for production of very low energy electron beam, by different thickness of Perspex spoilers, is presented that may be used for skin cancer. Aims: MCNPX Monte Carlo code was used for modeling and simulations in the current study. An energy spoiler Perspex was modeled for degrading 4 MeV electron beam of Varian 2300 CD Linac. Materials and Methods: The thicknesses of 3, 7, and 10 mm were applied before electron applicator at a distance of 42 cm from phantom surface. Dosimetric properties of new electron beams including Rp, Dmax, E0, as well as the penumbra of the beam were investigated. Results: For the 3 mm spoiler, the superficial beam output decreased to 77%, and the Dmax, R90, R50, and RP were shifted to the depths of 4, 6, 9, and 12 mm, respectively. While for 10 mm filter the results were 5.2, 3.0 and 5.0 mm for R90, R50, and Rp, respectively. In addition, the surface dose was 93% and the Dmax was shifted to the depth of 1mm for the 10mm Perspex spoiler slab. Conclusions: The presented beam provides a novel surface dose, Dmax, and RP which can be applicable for treatment of skin cancers with minimum dose to the beyond normal tissues.


Assuntos
Elétrons , Método de Monte Carlo , Neoplasias/radioterapia , Aceleradores de Partículas , Planejamento da Radioterapia Assistida por Computador , Algoritmos , Humanos , Neoplasias/diagnóstico , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/radioterapia
15.
Int J Radiat Biol ; 95(7): 1043-1049, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31157572

RESUMO

In the 60 years since the inaugural edition of the International Journal of Radiation Biology, much of our understanding of the biological effects of solar radiation has changed. Earlier in the century, sunlight played a 'hero's' role in reducing disabling rickets, while today debate still continues on the amount of sun required before exposure reveals the 'villainous' side of solar radiation. Although knowledge of the ultra violet (UV) component of sunlight as a carcinogen has become widespread, skin cancer rates are still rising yearly. Twentieth century attitudes have seen an about-face in the field of dermatological sun protection, with sunscreens changing from recipes designed to promote a 'healthy tan' to formulations proven to block both ultraviolet B (UVB) and more recently, ultraviolet A (UVA), to minimize premature sun-aging and skin cancer risk. In the early 1960s, DNA was first found to exist within mitochondria, while recently the connections between mitochondrial changes and UV radiation exposure have been expanded. Sixty years ago, understanding of the endocrine systems of mammals was enjoying its infancy. Early discoveries that light, particularly natural light, could have profound effects on functions such as sleep patterns and hormonal balance were made, while today more advanced knowledge has led to lighting improvements having pronounced effects on human wellbeing. Photosensitization 60 years ago was a health concern for both humans and their domestic animals, while today chemically engineered photosensitizing drugs can be administered along with highly directed light to pinpoint delivery targets for drug action. Life on earth is inextricably bound up with solar radiation. This article attempts to outline many of the ways in which our opinions about solar radiation have changed since the journal's inception.


Assuntos
Radiobiologia/história , Luz Solar , Raios Ultravioleta , Animais , DNA/efeitos da radiação , Dano ao DNA , DNA Mitocondrial/metabolismo , História do Século XX , História do Século XXI , Humanos , Saúde Mental , Mitocôndrias/efeitos da radiação , Neoplasias/etiologia , Neoplasias/radioterapia , Fármacos Fotossensibilizantes , Raquitismo/radioterapia , Pele/efeitos da radiação , Envelhecimento da Pele/efeitos da radiação , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/radioterapia , Vitamina D/metabolismo
16.
Cancer Radiother ; 23(4): 328-333, 2019 Jul.
Artigo em Francês | MEDLINE | ID: mdl-31153769

RESUMO

Brachytherapy of skin tumours uses custom applicators that are manufactured manually. The integration of 3D printing customization of applicators during hidh dose rate brachytherapy planning could allow a better skin conformation and a better reproducibility of the positioning and treatment. We present the technical implementation of this method for our first two patients. A provisional planning scanner was carried out to create a digital applicator. The creation of the digital applicator used successively several software programs. The first, commercial, was RhinocerosR 3D used via Grasshopper, an integrated open source plug-in. The 3D applicator was then exported to the commercial software Simplify3DR. A g-code format file was generated for the printer. A second scanner was made with a 3D applicator in place to plan the final treatment. The treatment was planned by reverse optimization. The applicator could be designed within 15 days. For patient A, it was noted that 95 % of the clinical target volume received at least 35.4Gy (63Gy EQD2). For patient B, 95 % of the clinical target volume received at least 36Gy (64.8Gy EQD2). The forecast and actual planimetry met the coverage criteria of D95. Contact brachytherapy with 3D bioimpression is feasible, after software training, for complex treatment lesions. This technique could be extended to other indications.


Assuntos
Braquiterapia/métodos , Impressão Tridimensional , Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias Cutâneas/radioterapia , Idoso de 80 Anos ou mais , Carcinoma Basocelular/radioterapia , Carcinoma de Células Escamosas/radioterapia , Neoplasias Faciais/radioterapia , Feminino , Humanos , Dosagem Radioterapêutica , Software
17.
Int J Radiat Oncol Biol Phys ; 104(5): 1141-1152, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31063799

RESUMO

PURPOSE: Despite the development of high-precision radiation therapy, ionizing radiation inevitably damages healthy tissues. Radiodermatitis and radioinduced oral mucositis are frequent and significant side effects among patients with breast and head and neck cancer, respectively. These radiation-related injuries negatively affect patient quality of life and can lead to unplanned therapeutic breaks and compromise treatment outcomes. Currently, no preventive or mitigating agent has emerged to address these issues. Although amifostine, a well-known free radical scavenger, has proven efficacy against specific radio- and chemo-induced toxicities, severe adverse side effects (reversible hypotension, nausea, emesis, etc) combined with logistical hurdles are associated with its recommended intravenous route of administration, limiting its use. METHODS AND MATERIALS: We developed a thermogel containing the active thiol metabolite of amifostine (CPh-1014) that polymerizes at body temperature and serves as a matrix for topical application onto the skin or mucosa. RESULTS: Applied before irradiation, CPh-1014 greatly reduced the severity of oral mucositis and dermatitis induced by either a single dose or fractionated irradiation regimens in in vivo mouse models. The cytoprotective effect of CPh-1014 was confirmed by the decrease in DNA double-strand breaks in the irradiated epithelium. Noticeably, CPh-1014 did not affect radiation therapy efficacy against tumors grafted at submucosal and subcutaneous sites. In contrast to the intravenous administration of amifostine, CPh-1014 oral application did not induce hypotension in dogs. CONCLUSIONS: CPh-1014 confers radioprotective effects in healthy tissues with reduced systemic side effects without compromising radiation therapy efficacy. We propose CPh-1014 as an easy-to-implement therapeutic approach to alleviate radiation therapy toxicity in patients with breast and head and neck cancer.


Assuntos
Amifostina/administração & dosagem , Géis/administração & dosagem , Lesões Experimentais por Radiação/prevenção & controle , Protetores contra Radiação/administração & dosagem , Radiodermatite/prevenção & controle , Estomatite/prevenção & controle , Amifostina/efeitos adversos , Animais , Pressão Sanguínea/efeitos dos fármacos , Neoplasias da Mama/radioterapia , Dano ao DNA , Modelos Animais de Doenças , Cães , Portadores de Fármacos , Feminino , Neoplasias de Cabeça e Pescoço/radioterapia , Hipotensão Ortostática/induzido quimicamente , Camundongos , Camundongos Endogâmicos C57BL , Lesões Experimentais por Radiação/tratamento farmacológico , Protetores contra Radiação/efeitos adversos , Radiodermatite/tratamento farmacológico , Distribuição Aleatória , Neoplasias Cutâneas/radioterapia , Estomatite/tratamento farmacológico , Estomatite/etiologia
18.
Med Dosim ; 44(2): 173-178, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31079619

RESUMO

Total Skin Electron Beam (TSEB) treatment, despite its proven effectiveness in skin malignancies, is a rather exhausting irradiation method, especially for feeble patients. In an effort to reduce treatment time by creating a clinically acceptable single TSEB field, various beam modifiers of different materials and shapes were tested. Using the TSEB immobilization device of our department and 3D printing technology, aluminum and thermoplastic modifiers were designed and constructed, according to the resulting profiles at treatment distance. Electron beam characteristics were measured and calculated both at SSD = 100 cm and at treatment level. Aluminum scatterers of the same thickness caused different modification according to the area of blocking. Aluminum modifiers reduced significantly central dose deposition for the same amount of MUs and therefore they expanded treatment time in undesirable levels. Plastic modifiers offer a good combination of field dimensions and treatment time. The final 3D printed modifier shaped the electron beam as desired resulting to a clinically acceptable 6 MeV field of 176 × 70 cm field with 10% inhomogeneity in vertical and 3% in the lateral dimension with adequate skin coverage at SSD = 400 cm. This modification offered approximately a two-minute treatment time reduction compared to the current technique. Underdosed areas appear near the edge of the field, but in regions that are far from the torso of the patient. Bremsstrahlung radiation was kept at clinically accepted levels (< 5%). This modification of the original six dual-field technique of our hospital could probably benefit fragile patients who could not easily tolerate a twenty-minute standing position without compromising the quality of their treatment.


Assuntos
Desenho de Equipamento , Impressão Tridimensional , Planejamento da Radioterapia Assistida por Computador/instrumentação , Neoplasias Cutâneas/radioterapia , Humanos , Aceleradores de Partículas , Imagens de Fantasmas , Radiometria , Dosagem Radioterapêutica
19.
J Appl Clin Med Phys ; 20(5): 44-54, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31033159

RESUMO

Mycosis fungoides is a disease with manifestation of the skin that has traditionally been treated with electron therapy. In this paper, we present a method of treating the entire skin with megavoltage photons using helical tomotherapy (HT), verified through a phantom study and clinical dosimetric data from our first two treated patients. A whole body phantom was fitted with a wetsuit as bolus, and scanned with computer tomography. We accounted for variations in daily setup using virtual bolus in the treatment plan optimization. Positioning robustness was tested by moving the phantom, and recalculating the dose at different positions. Patient treatments were verified with in vivo film dosimetry and dose reconstruction from daily imaging. Reconstruction of the actual delivered dose to the patients showed similar target dose as the robustness test of the phantom shifted 10 mm in all directions, indicating an appropriate approximation of the anticipated setup variation. In vivo film measurements agreed well with the calculated dose confirming the choice of both virtual and physical bolus parameters. Despite the complexity of the treatment, HT was shown to be a robust and feasible technique for total skin irradiation. We believe that this technique can provide a viable option for Tomotherapy centers without electron beam capability.


Assuntos
Micose Fungoide/radioterapia , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia de Intensidade Modulada/métodos , Neoplasias Cutâneas/radioterapia , Adulto , Idoso , Estudos de Viabilidade , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Prognóstico , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X/métodos
20.
Indian J Pathol Microbiol ; 62(2): 316-318, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30971566

RESUMO

Pagetoid reticulosis is an indolent cutaneous T-cell lymphoma and presents as erythema or plaque with a well-defined border on the distal areas of the extremities. Immunophenotypic studies show that in most cases, neoplastic lymphocytes are positive for CD4, whereas CD20 and CD30 double positivity was rarely reported. In this paper, we report an 80-year-old woman who presented with erythema on the extremities for 3 years. Skin biopsy on the right forearm was performed. Histopathologically, the erythematous lesions were characterized by atypical lymphocytes with significant epidermotropism. Immunohistochemical staining showed high proliferation as evidenced by high Ki-67 index and that the tumor cells were positive for CD20 and CD30 but negative for CD7 and CD56. The patient was treated with one cycle of radiotherapy and is currently doing well.


Assuntos
Antígenos CD20/genética , Antígeno Ki-1/genética , Reticulose Pagetoide/diagnóstico , Neoplasias Cutâneas/diagnóstico , Idoso de 80 Anos ou mais , Biópsia , Eritema , Feminino , Humanos , Imunofenotipagem , Linfócitos , Linfoma Cutâneo de Células T/diagnóstico , Reticulose Pagetoide/radioterapia , Pele/patologia , Neoplasias Cutâneas/radioterapia , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA