Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
1.
Clin Transl Radiat Oncol ; 47: 100783, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38706724

RESUMEN

Background and purpose: Many patients with solid tumors develop brain metastases (BM). With more patients surviving long-term, preservation of neurocognitive function gains importance. In recent years, several methods to delay cognitive deterioration have been tested in clinical trials. However, knowledge on the extent to which these neuroprotective strategies have been implemented in clinical practice is missing. Materials and methods: We performed an online survey regarding treatment patterns of BM in German-speaking countries, focused on the use of neuroprotective approaches. The survey was distributed among radiation oncologists (ROs) registered within the database of the German Society for Radiation Oncology (DEGRO). Results: Physicians of 78 centers participated in the survey. Whole brain radiotherapy (WBRT) is still preferred by 70 % of ROs over stereotactic radiotherapy (SRT) in patients with 6-10 BM. For 4-5 BM WBRT is preferred by 23 % of ROs. The fraction of ROs using hippocampal sparing (HS) in WBRT has increased to 89 %, although the technique is used on a regular basis only by a minority (26 %). The drug memantine is not widely prescribed (14% of ROs). A trend was observed for university hospitals to implement neuroprotective approaches more frequently. Conclusion: There is considerable heterogeneity regarding the treatment of BM in German-speaking countries and a general standard of care is lacking. Neuroprotective strategies are not yet standard approaches in daily clinical routine, although usage is increasing. Further clinical trials, as well as improvement of technical opportunities and reimbursement, might further shift the treatment landscape towards neuroprotective radiation treatments in the future.

2.
Strahlenther Onkol ; 200(4): 335-345, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-37646818

RESUMEN

PURPOSE: This study aimed to assess clinical, treatment, and prognostic features in patients with brain metastases (BM) from solid tumors achieving long-term survival (LTS). Further, the accuracy of diagnosis-specific Graded Prognostic Assessment scores (ds-GPA) to predict LTS was evaluated. METHODS: Patients admitted for radiotherapy of BM between 2010 and 2020 at a large tertiary cancer center with survival of at least 3 years from diagnosis of BM were included. Patient, tumor, treatment characteristics and ds-GPA were compiled retrospectively. RESULTS: From a total of 1248 patients with BM, 61 (4.9%) survived ≥ 3 years. In 40 patients, detailed patient charts were available. Among LTS patients, median survival time from diagnosis of BM was 51.5 months. Most frequent primary tumors were lung cancer (45%), melanoma (20%), and breast cancer (17.5%). At the time of diagnosis of BM, 11/40 patients (27.5%) had oligometastatic disease. Estimated mean survival time based on ds-GPA was 19.7 months (in 8 cases estimated survival < 12 months). Resection followed by focal or whole-brain radiotherapy (WBRT) was often applied (60%), followed by primary stereotactic radiotherapy (SRT) (20%) or WBRT (20%). 80% of patients received systemic treatment, appearing particularly active in specifically altered non-small lung cancer (NSCLC), melanoma, and HER2-positive breast cancer. Karnofsky performance score (KPS) and the presence of oligometastatic disease at BM diagnosis were persisting prognostic factors in LTS patients. CONCLUSION: In this monocentric setting reflecting daily pattern of care, LTS with BM is heterogeneous and difficult to predict. Effective local treatment and modern systemic therapies often appear crucial for LTS. The impact of concomitant diseases and frailty is not clear.


Asunto(s)
Neoplasias Encefálicas , Neoplasias de la Mama , Neoplasias Pulmonares , Melanoma , Radiocirugia , Humanos , Femenino , Estudios Retrospectivos , Neoplasias Pulmonares/patología , Pronóstico , Neoplasias Encefálicas/secundario , Radiocirugia/efectos adversos , Neoplasias de la Mama/patología
3.
BMC Cancer ; 22(1): 337, 2022 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-35351058

RESUMEN

OBJECTIVE: Failure rate in randomized controlled trials (RCTs) is > 50%, includes safety-problems, underpowered statistics, lack of efficacy, lack of funding or insufficient patient recruitment and is even more pronounced in oncology trials. We present results of a structured concept-development phase (CDP) for a phase III RCT on personalized radiotherapy (RT) in primary prostate cancer (PCa) patients implementing prostate specific membrane antigen targeting positron emission tomography (PSMA-PET). MATERIALS AND METHODS: The 1 yr process of the CDP contained five main working packages: (i) literature search and scoping review, (ii) involvement of individual patients, patients' representatives and patients' self-help groups addressing the patients' willingness to participate in the preparation process and the conduct of RCTs as well as the patient informed consent (PIC), (iii) involvement of national and international experts and expert panels (iv) a phase II pilot study investigating the safety of implementation of PSMA-PET for focal dose escalation RT and (v) in-silico RT planning studies assessing feasibility of envisaged dose regimens and effects of urethral sparing in focal dose escalation. RESULTS: (i) Systematic literature searches confirmed the high clinical relevance for more evidence on advanced RT approaches, in particular stereotactic body RT, in high-risk PCa patients. (ii) Involvement of patients, patient representatives and randomly selected males relevantly changed the PIC and initiated a patient empowerment project for training of bladder preparation. (iii) Discussion with national and international experts led to adaptions of inclusion and exclusion criteria. (iv) Fifty patients were treated in the pilot trial and in- and exclusion criteria as well as enrollment calculations were adapted accordingly. Parallel conduction of the pilot trial revealed pitfalls on practicability and broadened the horizon for translational projects. (v) In-silico planning studies confirmed feasibility of envisaged dose prescription. Despite large prostate- and boost-volumes of up to 66% of the prostate, adherence to stringent anorectal dose constraints was feasible. Urethral sparing increased the therapeutic ratio. CONCLUSION: The dynamic framework of interdisciplinary working programs in CDPs enhances robustness of RCT protocols and may be associated with decreased failure rates. Structured recommendations are warranted to further define the process of such CDPs in radiation oncology trials.


Asunto(s)
Neoplasias de la Próstata , Oncología por Radiación , Estudios de Factibilidad , Humanos , Masculino , Próstata , Neoplasias de la Próstata/radioterapia , Tomografía Computarizada por Rayos X
4.
Strahlenther Onkol ; 198(1): 1-11, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34786605

RESUMEN

The new Medical Licensing Regulations 2025 (Ärztliche Approbationsordnung, ÄApprO) will soon be passed by the Federal Council (Bundesrat) and will be implemented step by step by the individual faculties in the coming months. The further development of medical studies essentially involves an orientation from fact-based to competence-based learning and focuses on practical, longitudinal and interdisciplinary training. Radiation oncology and radiation therapy are important components of therapeutic oncology and are of great importance for public health, both clinically and epidemiologically, and therefore should be given appropriate attention in medical education. This report is based on a recent survey on the current state of radiation therapy teaching at university hospitals in Germany as well as the contents of the National Competence Based Learning Objectives Catalogue for Medicine 2.0 (Nationaler Kompetenzbasierter Lernzielkatalog Medizin 2.0, NKLM) and the closely related Subject Catalogue (Gegenstandskatalog, GK) of the Institute for Medical and Pharmaceutical Examination Questions (Institut für Medizinische und Pharmazeutische Prüfungsfragen, IMPP). The current recommendations of the German Society for Radiation Oncology (Deutsche Gesellschaft für Radioonkologie, DEGRO) regarding topics, scope and rationale for the establishment of radiation oncology teaching at the respective faculties are also included.


Asunto(s)
Docentes Médicos , Oncología por Radiación , Competencia Clínica , Curriculum , Alemania , Humanos , Oncología por Radiación/educación
5.
HNO ; 69(4): 278-284, 2021 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-33048200

RESUMEN

BACKGROUND: In contrast to alcohol- and nicotine-induced head and neck tumors, human papillomavirus (HPV)-positive oropharyngeal carcinoma rather affects younger patients, and the incidence of this entity is continuously increasing. Due to the significantly better prognosis of HPV-positive oropharyngeal carcinoma, various treatment de-escalation strategies are currently being investigated, with the aim of reducing toxicity without affecting the good survival rates of these patients. OBJECTIVE: This study aims to evaluate the evidence for treatment de-escalation in HPV-positive oropharyngeal carcinoma. MATERIALS AND METHODS: A literature search was performed and relevant studies are critically discussed. RESULTS: De-escalation strategies for HPV-associated oropharyngeal carcinoma using induction chemotherapy or radiation dose reduction have demonstrated good oncological results in phase II trials, with lower toxicity rates compared to historical controls. However, both of the first published phase III trials investigating de-escalation of concomitant chemotherapy regimens demonstrated inferior outcomes for the deescalated treatment strategies without improvements in treatment-associated toxicities. Additional phase-III trials investigating other de-escalation strategies have not yet been published. CONCLUSION: Treatment de-escalation should be performed exclusively in prospective studies and can currently not be recommended in clinical routine.


Asunto(s)
Carcinoma , Neoplasias Orofaríngeas , Infecciones por Papillomavirus , Quimioradioterapia/efectos adversos , Humanos , Neoplasias Orofaríngeas/terapia , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/terapia , Estudios Prospectivos
6.
Radiat Oncol ; 15(1): 171, 2020 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-32653003

RESUMEN

BACKGROUND: To date, only limited magnetic resonance imaging (MRI) data are available concerning tumor regression during neoadjuvant radiochemotherapy (RCT) of rectal cancer patients, which is a prerequisite for adaptive radiotherapy (RT) concepts. This exploratory study prospectively evaluated daily fractional MRI during neoadjuvant treatment to analyze the predictive value of MR biomarkers for treatment response. METHODS: Locally advanced rectal cancer patients were examined with daily MRI during neoadjuvant RCT. Contouring of the tumor volume was performed for each MRI scan by using T2- and diffusion-weighted-imaging (DWI)-sequences. The daily apparent-diffusion coefficient (ADC) was calculated. Volumetric and functional tumor changes during RCT were analyzed and correlated with the pathological response after surgical resection. RESULTS: In total, 171 MRI scans of eight patients were analyzed regarding anatomical and functional dynamics during RCT. Pathological complete response (pCR) could be achieved in four patients, and four patients had a pathological partial response (pPR) following neoadjuvant treatment. T2- and DWI-based volumetry proved to be statistically significant in terms of therapeutic response, and volumetric thresholds at week two and week four during RCT were defined for the prediction of pCR. In contrast, the average tumor ADC values widely overlapped between both response groups during RCT and appeared inadequate to predict treatment response in our patient cohort. CONCLUSION: This prospective exploratory study supports the hypothesis that MRI may be able to predict pCR of rectal cancers early during neoadjuvant RCT. Our data therefore provide a useful template to tailor future MR-guided adaptive treatment concepts.


Asunto(s)
Quimioradioterapia , Imagen de Difusión por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/métodos , Neoplasias del Recto/terapia , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Terapia Neoadyuvante , Estudios Prospectivos , Planificación de la Radioterapia Asistida por Computador , Neoplasias del Recto/diagnóstico por imagen , Neoplasias del Recto/patología
7.
Eur J Nucl Med Mol Imaging ; 47(5): 1056-1064, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31773233

RESUMEN

PURPOSE: The aim of this study was to investigate whether textural features of tumour hypoxia, assessed with serial [18F]fluoromisonidazole (FMISO)-PET, were able to predict clinical outcome in patients with head and neck squamous cell carcinoma (HNSCC, T1-4, N+, M0) during chemoradiotherapy (CRT). METHODS: In a preliminary evaluation of a prospective trial, tumour hypoxia was evaluated in 29 patients via serial FMISO-PET before and during CRT. All patients received an initial [18F]fluorodeoxyglucose (FDG)-PET before CRT, and tumour regions were defined on this FDG-PET. The first-order metrics tumour-to-background ratio (TBRmean, TBRmax, TBRpeak), coefficient of variation, total lesion uptake and integral non-uniformity were calculated for all scans. Further, 3 second-order (textural) features from two grey-level matrices were calculated, as well as differential non-uniformity (udiff). Prognostic value was examined by median split for group separation (GS) in Kaplan-Meier estimates and correlated with overall survival (OS), quantified via log-rank tests (p ≤ 0.05) and group-relative hazard ratios (HR). RESULTS: Within a median follow-up of 29.6 months (95% CI: 16.8-48.0 months), no first-order metrics predicted OS with a significant GS (all p > 0.05) on any FMISO-PET scan. Only udiff before and in week 2 during CRT (p = 0.03, HR = 10.8 and p = 0.05, HR = 5.2) and non-uniformity from grey-level run length matrix in week 2 separated prognostic groups (p = 0.05, HR = 5.3); lower values were correlated with better OS. Further, the decrease in udiff from before CRT to week 2 was correlated with better OS (p = 0.04, HR = 9.4). FDG-PET before CRT did not predict outcome in any measure. CONCLUSIONS: Textural features on FMISO-PET scans before CRT, in week 2 and, to a limited degree, the change of features during CRT, were able to identify head and neck squamous cell carcinoma patients with better OS, suggesting that a higher homogeneity of the degree of hypoxia in tumours could correlate with a better outcome after CRT.


Asunto(s)
Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello , Quimioradioterapia , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/terapia , Humanos , Hipoxia , Tomografía de Emisión de Positrones , Estudios Prospectivos
11.
Oncogene ; 29(3): 463-8, 2010 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-19838217

RESUMEN

A significant proportion of human cancers overexpress DNA polymerase beta (Pol beta), the major DNA polymerase involved in base excision repair. The underlying mechanism and biological consequences of overexpression of this protein are unknown. We examined whether Pol beta, expressed at levels found in tumor cells, is involved in the repair of DNA damage induced by oxaliplatin treatment and whether the expression status of this protein alters the sensitivity of cells to oxaliplatin. DNA damage induced by oxaliplatin treatment of HCT116 and HT29 colon cancer cells was observed to be associated with the stabilization of Pol beta protein on chromatin. In comparison with HCT116 colon cancer cells, isogenic oxaliplatin-resistant (HCT-OR) cells were found to have higher constitutive levels of Pol beta protein, faster in vitro repair of a DNA substrate containing a single nucleotide gap and faster repair of 1,2-GG oxaliplatin adduct levels in cells. In HCT-OR cells, small interfering RNA knockdown of Pol beta delayed the repair of oxaliplatin-induced DNA damage. In a different model system, Pol beta-deficient fibroblasts were less able to repair 1,2-GG oxaliplatin adducts and were hypersensitive to oxaliplatin treatment compared with isogenic Pol beta-expressing cells. Consistent with previous studies, Pol beta-deficient mouse fibroblasts were not hypersensitive to cisplatin treatment. These data provide the first link between oxaliplatin sensitivity and DNA repair involving Pol beta. They demonstrate that Pol beta modulates the sensitivity of cells to oxaliplatin treatment.


Asunto(s)
ADN Polimerasa beta/metabolismo , Compuestos Organoplatinos/farmacología , Animales , Antineoplásicos/farmacología , Western Blotting , Línea Celular , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Daño del ADN , ADN Polimerasa beta/deficiencia , ADN Polimerasa beta/genética , Reparación del ADN/genética , Resistencia a Antineoplásicos/genética , Células HCT116 , Células HT29 , Humanos , Ratones , Ratones Noqueados , Oxaliplatino , Interferencia de ARN , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Factores de Tiempo
12.
Chirurg ; 78(9): 835-9, 2007 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-17505813

RESUMEN

BACKGROUND: In cases of near-total ear avulsions, replantation is often successful without microsurgery. The purpose of our study was to investigate the relevant vascular anatomy associated for ear survival. PATIENTS AND METHODS: Four cases of successful surgical intervention in near-total ear avulsions are presented. Injection studies using latex were performed to identify the blood supply to the auricle on 13 cadaveric ears. RESULTS: A small superior branch of the superficial temporal artery above the tragus was identified extending along the upper border of the auricle and connecting with the helical arcade. Below the tragus, a second small horizontal branch of the superficial temporal artery was identified. CONCLUSION: The auricle can survive near-total amputation based on a skin bridge above or below the tragus. One of the auricular branches of the superficial temporal artery seems sufficient for the blood supply to the ear and allows for a successful non-microsurgical operative repair.


Asunto(s)
Amputación Traumática/cirugía , Oído Externo/lesiones , Oído Externo/cirugía , Reimplantación , Accidentes por Caídas , Accidentes de Trabajo , Accidentes de Tránsito , Adulto , Amputación Traumática/etiología , Cadáver , Preescolar , Oído Externo/anatomía & histología , Oído Externo/irrigación sanguínea , Femenino , Humanos , Masculino , Persona de Mediana Edad , Arterias Temporales , Resultado del Tratamiento
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...