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1.
Urologe A ; 59(4): 416-425, 2020 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-32130447

RESUMO

As useful and necessary as radiotherapy may be, it is associated with irreversible long-term adverse effects including loss of bladder function. In the majority of cases the small bowel, sigmoid rectum and ureter are also affected. The extent of injury depends on the irradiated area, the applied dose and the quality of application. Three factors are essential when choosing a urinary diversion: the length of functional ureter, the position of the bowel outside of the irradiated area and the type of diversion. A continent diversion is best performed through a ascending-transverse or transverse-descending colon pouch. The efferent segment is diverted through the umbilicus. The simplest technique for an incontinent diversion is a conduit using the ascending colon or the right colon flexure. If the length of the ureter does not suffice for such a conduit, the ideal solution is a transverse conduit, as this conduit can be attached to both renal pelves, while simultaneously allowing free choice of the lateral location of the stoma. In case of an exenteration, a double stoma on one side of the body should be avoided in order to prevent maintenance issues.


Assuntos
Pelve Menor/efeitos da radiação , Pelve/efeitos da radiação , Lesões por Radiação , Derivação Urinária , Colo , Humanos , Ureter
2.
Dermatol Online J ; 26(1)2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32155033

RESUMO

Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome (SJS) are life-threatening, cutaneous reactions often associated with culprit drugs. A growing body of knowledge has deepened our understanding of the pathophysiology and clarified mechanisms such as drug-specific cytotoxicity mediated by T-cells, genetic linkage with HLA and non-HLA genes, TCR restriction, and cytotoxicity mechanisms. Physicians should broadly consider the etiology of SJS/TEN in order to better understand treatment strategies as well as identify which patients may be at risk for developing this condition. Mechanisms for how radiotherapy and rare malignancies may contribute to the development of TEN and SJS have been proposed.


Assuntos
Lipossarcoma/radioterapia , Radioterapia/efeitos adversos , Síndrome de Stevens-Johnson/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Lesões por Radiação , Pele/patologia , Síndrome de Stevens-Johnson/patologia
3.
Life Sci ; 250: 117570, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32205088

RESUMO

Accidental exposure to ionizing radiation is a serious concern to human life. Studies on the mitigation of side effects following exposure to accidental radiation events are ongoing. Recent studies have shown that radiation can activate several signaling pathways, leading to changes in the metabolism of free radicals including reactive oxygen species (ROS) and nitric oxide (NO). Cellular and molecular mechanisms show that radiation can cause disruption of normal reduction/oxidation (redox) system. Mitochondria malfunction following exposure to radiation and mutations in mitochondria DNA (mtDNA) have a key role in chronic oxidative stress. Furthermore, exposure to radiation leads to infiltration of inflammatory cells such as macrophages, lymphocytes and mast cells, which are important sources of ROS and NO. These cells generate free radicals via upregulation of some pro-oxidant enzymes such as NADPH oxidases, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Epigenetic changes also have a key role in a similar way. Other mediators such as mammalian target of rapamycin (mTOR) and peroxisome proliferator-activated receptor (PPAR), which are involved in the normal metabolism of cells have also been shown to regulate cell death following exposure to radiation. These mechanisms are tissue specific. Inhibition or activation of each of these targets can be suggested for mitigation of radiation injury in a specific tissue. In the current paper, we review the cellular and molecular changes in the metabolism of cells and ROS/NO following exposure to radiation. Furthermore, the possible strategies for mitigation of radiation injury through modulation of cellular metabolism in irradiated organs will be discussed.


Assuntos
Estresse Oxidativo/efeitos da radiação , Lesões por Radiação/metabolismo , Animais , Ciclo-Oxigenase 2/metabolismo , DNA Mitocondrial/genética , Epigênese Genética , Humanos , Inflamação , Linfócitos/citologia , Mastócitos/citologia , Camundongos , Mitocôndrias/efeitos da radiação , Mutação , NADPH Oxidases/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Oxirredução , Radiação Ionizante , Espécies Reativas de Oxigênio/metabolismo
4.
Medicine (Baltimore) ; 99(10): e19517, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32150113

RESUMO

INTRODUCTION: Radiotherapy is a valid treatment option for nasopharyngeal carcinoma. However, complications can occur following irradiation of the closest anatomical structures, including brainstem radionecrosis (BRN). The rehabilitation is poorly described in patients with BRN, despite its usefulness in improving functional independence in patients with brain tumors. We aimed at testing the usefulness of intensive, robot-assisted neurorehabilitation program to improve functional independence in a 57-year-old male with BRN. PATIENT CONCERNS: A 57-year-old male diagnosed with a nasopharyngeal carcinoma, received a radiation total dose of 72 Gy. Owing to the appearance of a severe symptomatology characterized by dysphagia, hearing loss, and left sided hemiparesis, the patient was hospitalized to be provided with intensive pharmacological and neurorehabilitation treatment. DIAGNOSIS: Follow-up brain magnetic resonance imaging disclosed no residual cancer, but some brainstem lesions compatible with BRN areas were appreciable. INTERVENTION: The patient underwent a 2-month conventional, respiratory, and speech therapy. Given that the patient only mildly improved, he was provided with intensive robot-aided upper limb and gait training and virtual reality-based cognitive rehabilitation for other 2 months. OUTCOMES: The patient reported a significant improvement in functional independence, spasticity, cognitive impairment degree, and balance. CONCLUSION: Our case suggests the usefulness of neurorobotic intensive rehabilitation in BRN to reduce functional disability. Future studies should investigate whether an earlier, even multidisciplinary rehabilitative treatment could lead to better functional outcome in patients with BRN.


Assuntos
Tronco Encefálico/lesões , Terapia por Exercício , Neoplasias Nasofaríngeas/radioterapia , Lesões por Radiação/reabilitação , Robótica , Tronco Encefálico/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Paresia/reabilitação , Lesões por Radiação/diagnóstico por imagem
5.
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
6.
Cancer Radiother ; 24(2): 93-98, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32057645

RESUMO

OBJECTIVE: Postradiation nasopharyngeal necrosis (PRNN) is a notorious complication after radiotherapy that affects prognosis in patients with nasopharyngeal carcinoma (NPC). It is important for clinical doctors to realize this problem in order to cope with this severe clinical situation. The aim of our study was to assess the bacteriology of PRNN and to demonstrate the antimicrobial susceptibility pattern that should guide the clinicians towards more appropriate antibiotic use. METHODS: Sixty-nine NPC patients with PRNN in our department between March 2013 and December 2017 were retrospectively enrolled. Pathogenic culture and drug sensitivity test were performed in these 69 NPC patients with PRNN. The infection rate of Pathogens and the sensitivity of the drugs were analyzed based on these results. RESULTS: Sixty-nine NPC patients with PRNN were enrolled in our study. Pathogens were identified in 58 (84%) patients. Of the 58 patients, Staphylococcus aureus was isolated in 34 (58.6%) patients. And the second most common group of bacterial isolates was Pseudomonas aeruginosa. Antibiotic sensitivity showed that Levofloxacin was the highest (88.5%), followed by Ciprofloxacin (85.2%) and Gentamicin (80.3%). The only pathologic fungus was Candidaalbicans, about 6.8%. The positive rates of bacterial and fungal culture in PRNN patients were not significantly different from the patients' gender, age, stage, number of radiotherapy courses (P>0.05), but the cure rate was statistically higher in culture-negative patients in comparison with culture-positive patients (63.6% vs 20.7%, P=0.011). CONCLUSION: Our results provide an overall picture of the microbiology and drug susceptibility patterns for NPC patients with PRNN and could help implement guidelines for more rational treatment and improve therapeutic outcome.


Assuntos
Antibacterianos/uso terapêutico , Carcinoma Nasofaríngeo/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Nasofaringe/efeitos da radiação , Lesões por Radiação/microbiologia , Adulto , Idoso , Candida albicans/efeitos dos fármacos , Ciprofloxacino/uso terapêutico , Feminino , Gentamicinas/uso terapêutico , Humanos , Levofloxacino/uso terapêutico , Masculino , Pessoa de Meia-Idade , Nasofaringe/diagnóstico por imagem , Nasofaringe/patologia , Necrose/diagnóstico por imagem , Necrose/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Lesões por Radiação/diagnóstico por imagem , Lesões por Radiação/patologia , Estudos Retrospectivos , Staphylococcus aureus/efeitos dos fármacos , Resultado do Tratamento
7.
World Neurosurg ; 136: e646-e659, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32001408

RESUMO

BACKGROUND: Treatment for surgically inaccessible medically refractory cerebral radiation necrosis (RN) has remained limited. Recently, laser interstitial thermal therapy (LITT) has gained traction as an effective means of treating these lesions but limited data are available regarding the effect of ablation size on patient outcome. Therefore, this study analyzed various outcome measures as a function of ablation volume/diameter for a series of 20 patients with surgically inaccessible biopsy-proven RN. METHODS: Twenty patients with biopsy-proven RN treated with LITT from 2013 to 2018 at our institution were retrospectively reviewed. Local progression-free survival (PFS), overall survival, and steroid dependence were analyzed with Kaplan-Meier and Cox regression analysis for ablation volume/diameter. Comparison of preoperative and postoperative Karnofsky Performance Status was conducted with a matched paired t test. RESULTS: Patients with subtotal ablation (<100% increase in pre-LITT lesion volume or <0 mm increase in pre-LITT lesion diameter) had higher risk of local disease progression (hazard ratio, 12.4; P = 0.004) compared with patients with total ablations. Patients who received radical ablations (>200% increase in pre-LITT lesion volume or >2 mm increase in pre-LITT lesion diameter) showed the most favorable PFS (P < 0.0458 and P < 0.0378, respectively). There was no difference in post-LITT Karnofsky Performance Status and time to steroid freedom between ablation groups. Overall survival increased with radical diametric ablation (P = 0.0401). CONCLUSIONS: Although LITT has proved to be an effective salvage therapy for patients with RN, detailed volumetric studies have not been explored. Our results suggest that radical ablations have the potential to increase PFS.


Assuntos
Ablação por Cateter/métodos , Terapia a Laser/métodos , Lesões por Radiação/cirurgia , Ablação por Cateter/mortalidade , Feminino , Humanos , Terapia a Laser/mortalidade , Masculino , Pessoa de Meia-Idade , Necrose/cirurgia , Intervalo Livre de Progressão , Estudos Prospectivos , Lesões por Radiação/mortalidade , Terapia de Salvação/métodos , Resultado do Tratamento
8.
Bratisl Lek Listy ; 121(1): 67-72, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31950842

RESUMO

AIM: Cancer treatments specially with new high Tec radiotherapy equipment's calling daily progression in method and predictive factors affecting treatment goals. Due to important effect of oxygen on cells radio sensitivity, tumor blood circulation and it's antigens like ABO blood groups maybe an important predictive factor for radiotherapy response and it is adverse events. The aim of this study was the assessment of the hematological manifestations of local radiotherapy and association with ABO blood groups. METHODS: In this observational study, 2 ml of peripheral blood were taken from 152 patients with routine 3D conformal radiotherapy treatment course and the blood parameters achieve and documented at four stage during treatment courses. The data were analyzed by repeated measurement andone-way ANOVA. RESULTS: Statistically significant reductions of the platelets, white blood cells (WBC), and lymphocytes counts were demonstrated. Also an increased percentage of polymorphonuclear cells during local radiotherapy exposure was found. The changes in WBC counts were observed to be in association with ABO blood groups. The other evaluated factors were not significantly associated with ABO blood groups. CONCLUSIONS: Our results showed an association between radiotherapy patients ABO blood groups and some hematological changes in their blood circulation (Fig. 7, Ref. 23).


Assuntos
Sistema ABO de Grupos Sanguíneos , Circulação Sanguínea , Neoplasias , Lesões por Radiação , Humanos , Contagem de Leucócitos , Neoplasias/radioterapia , Prognóstico
9.
Expert Opin Pharmacother ; 21(3): 317-337, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31928256

RESUMO

Introduction: There is a limited array of currently available medicinals that are useful for either the prevention, mitigation or treatment of bodily injuries arising from ionizing radiation exposure.Area covered: In this brief article, the authors review those pharmacologic agents that either are currently being used to counter the injurious effects of radiation exposure, or those that show promise and are currently under development.Expert opinion: Although significant, but limited progress has been made in the development and fielding of safe and effective pharmacotherapeutics for select types of acute radiation-associated injuries, additional effort is needed to broaden the scope of drug development so that overall health risks associated with both short- and long-term injuries in various organ systems can be reduced and effectively managed. There are several promising radiation countermeasures that may gain regulatory approval from the government in the near future for use in clinical settings and in the aftermath of nuclear/radiological exposure contingencies.


Assuntos
Lesões por Radiação/tratamento farmacológico , Radiação Ionizante , Protetores contra Radiação/administração & dosagem , Animais , Humanos
10.
Br J Radiol ; 93(1107): 20190845, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31904261

RESUMO

OBJECTIVES: The purpose of this study is to investigate the dosimetric effect and clinical impact of delivering a focal radiotherapy boost dose to multiparametric MRI (mp-MRI)-defined dominant intraprostatic lesions (DILs) in prostate cancer using proton therapy. METHODS: We retrospectively investigated 36 patients with pre-treatment mp-MRI and CT images who were treated using pencil beam scanning (PBS) proton radiation therapy to the whole prostate. DILs were contoured on co-registered mp-MRIs. Simultaneous integrated boost (SIB) plans using intensity-modulated proton therapy (IMPT) were created based on conventional whole-prostate-irradiation for each patient and optimized with additional DIL coverage goals and urethral constraints. DIL dose coverage and organ-at-risk (OAR) sparing were compared between conventional and SIB plans. Tumor control probability (TCP) and normal tissue complication probability (NTCP) were estimated to evaluate the clinical impact of the SIB plans. RESULTS: Optimized SIB plans significantly escalated the dose to DILs while meeting OAR constraints. SIB plans were able to achieve 125, 150 and 175% of prescription dose coverage in 74, 54 and 17% of 36 patients, respectively. This was modeled to result in an increase in DIL TCP by 7.3-13.3% depending on α/ß and DIL risk level. CONCLUSION: The proposed mp-MRI-guided DIL boost using proton radiation therapy is feasible without violating OAR constraints and demonstrates a potential clinical benefit by improving DIL TCP. This retrospective study suggested the use of IMPT-based DIL SIB may represent a strategy to improve tumor control. ADVANCES IN KNOWLEDGE: This study investigated the planning of mp-MRI-guided DIL boost in prostate proton radiation therapy and estimated its clinical impact with respect to TCP and NTCP.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/radioterapia , Terapia com Prótons/métodos , Reirradiação/métodos , Idoso , Idoso de 80 Anos ou mais , Fracionamento da Dose de Radiação , Humanos , Masculino , Pessoa de Meia-Idade , Tratamentos com Preservação do Órgão/métodos , Órgãos em Risco/diagnóstico por imagem , Órgãos em Risco/efeitos da radiação , Próstata/diagnóstico por imagem , Próstata/efeitos da radiação , Neoplasias da Próstata/patologia , Lesões por Radiação/prevenção & controle , Dosagem Radioterapêutica , Estudos Retrospectivos , Tomografia Computadorizada por Raios X , Uretra/diagnóstico por imagem
11.
Br J Radiol ; 93(1107): 20190955, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31971818

RESUMO

Patients with squamous cell carcinoma of the oropharynx are generally treated with (chemo) radiation. Patients with oropharyngeal cancer have better survival than patients with squamous cell carcinoma of other head and neck subsites, especially when related to human papillomavirus. However, radiotherapy results in a substantial percentage of survivors suffering from significant treatment-related side-effects. Late radiation-induced side-effects are mostly irreversible and may even be progressive, and particularly xerostomia and dysphagia affect health-related quality of life. As the risk of radiation-induced side-effects highly depends on dose to healthy normal tissues, prevention of radiation-induced xerostomia and dysphagia and subsequent improvement of health-relatedquality of life can be obtained by applying proton therapy, which offers the opportunity to reduce the dose to both the salivary glands and anatomic structures involved in swallowing.This review describes the results of the first cohort studies demonstrating that proton therapy results in lower dose levels in multiple organs at risk, which translates into reduced acute toxicity (i.e. up to 3 months after radiotherapy), while preserving tumour control. Next to reducing mucositis, tube feeding, xerostomia and distortion of the sense of taste, protons can improve general well-being by decreasing fatigue and nausea. Proton therapy results in decreased rates of tube feeding dependency and severe weight loss up to 1 year after radiotherapy, and may decrease the risk of radionecrosis of the mandible. Also, the model-based approach for selecting patients for proton therapy in the Netherlands is described in this review and future perspectives are discussed.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Transtornos de Deglutição/prevenção & controle , Neoplasias Orofaríngeas/radioterapia , Terapia com Prótons/métodos , Lesões por Radiação/prevenção & controle , Xerostomia/prevenção & controle , Idoso , Transtornos de Deglutição/etiologia , Nutrição Enteral/estatística & dados numéricos , Humanos , Mandíbula/efeitos da radiação , Pessoa de Meia-Idade , Países Baixos , Órgãos em Risco/efeitos da radiação , Qualidade de Vida , Glândulas Salivares/efeitos da radiação , Xerostomia/etiologia
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