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1.
Strahlenther Onkol ; 199(11): 982-991, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37428207

RESUMEN

BACKGROUND: Pancreatic cancer accounts for around 4.6% of cancers deaths worldwide per year. Despite many advances in treatment regimes, the prognosis is still poor. Only 20% of tumors are primarily resectable. Recurrences-both with distant metastasis as well as locoregional-are frequent. For patients with primary nonresectable localized disease or localized recurrences, we offered chemoradiation to achieve local control over a long period of time. We here report our results on combined chemoradiation of pancreatic tumors and local recurrences using proton beam therapy. MATERIALS AND METHODS: We report on 25 patients with localized nonresectable pancreatic cancer (15 patients) or local recurrent disease (10 patients). All patients were treated with combined proton radiochemotherapy. Overall survival, progression-free survival, local control, and treatment-related toxicity were analyzed using statistically methods. RESULTS: Median RT dose was 54.0 Gy (RBE) for proton irradiation. The toxicity of treatment was acceptable. Four CTCAE grade III and IV adverse events (bone marrow disfunction, gastrointestinal [GI] disorders, stent dislocation, myocardial infarction) were recorded during or directly after the end of radiotherapy; two of them were related to combined chemoradiation (bone marrow disfunction, GI disorders). Six weeks after radiotherapy, one additional grade IV toxicity was reported (ileus, caused by peritoneal carcinomatosis, not treatment related). The median progression-free survival was 5.9 months and median overall survival was 11.0 months. The pretherapy CA19­9 level was a statistically significant prognostic factor for enhanced overall survival. Local control at 6 months and 12 months were determined to be 86% and 80%, respectively. CONCLUSION: Combined proton chemoradiation leads to high local control rates. Unfortunately, PFS and OS are driven by distant metastasis and were not improved compared to historical data and reports. With this in mind, enhanced chemotherapeutical regimes, in combination with local irradiation, should be evaluated.


Asunto(s)
Enfermedades Gastrointestinales , Neoplasias Pancreáticas , Terapia de Protones , Humanos , Gemcitabina , Protones , Neoplasias Pancreáticas/patología , Terapia de Protones/métodos , Enfermedades Gastrointestinales/etiología , Recurrencia Local de Neoplasia , Neoplasias Pancreáticas
3.
Strahlenther Onkol ; 198(10): 919-925, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36006436

RESUMEN

PURPOSE: Preoperative stereotactic radiosurgery (SRS) of brain metastases may achieve similar local control and better leptomeningeal control rates than postoperative fractionated stereotactic radiotherapy (FSRT) in patients treated with elective metastasectomy. To plan a multicentre trial of preoperative SRS compared with postoperative FSRT, a survey of experts was conducted to determine current practice. METHODS: A survey with 15 questions was distributed to the DEGRO Radiosurgery and Stereotactic Radiotherapy Working Group. Participants were asked under what circumstances they offered SRS, FSRT, partial and/or whole brain radiotherapy before or after resection of a brain metastasis, as well as the feasibility of preoperative stereotactic radiosurgery and neurosurgical resection within 6 days. RESULTS: Of 25 participants from 24 centres, 22 completed 100% of the questions. 24 respondents were radiation oncologists and 1 was a neurosurgeon. All 24 centres have one or more dedicated radiosurgery platform and all offer postoperative FSRT. Preoperative SRS is offered by 4/24 (16.7%) centres, and 9/24 (37.5%) sometimes recommend single-fraction postoperative SRS. Partial brain irradiation is offered by 8/24 (33.3%) centres and 12/24 (50%) occasionally recommend whole-brain irradiation. Two centres are participating in clinical trials of preoperative SRS. SRS techniques and fractionation varied between centres. CONCLUSION: All responding centres currently offer postoperative FSRT after brain metastasectomy. Approximately one third offer single-fraction postoperative SRS and four already perform preoperative SRS. With regard to potential co-investigators, 18 were identified for the PREOP­2 multicentre trial, which will randomise between preoperative SRS and postoperative FSRT.


Asunto(s)
Neoplasias Encefálicas , Oncología por Radiación , Radiocirugia , Encéfalo , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/cirugía , Fraccionamiento de la Dosis de Radiación , Humanos , Radiocirugia/métodos
4.
Strahlenther Onkol ; 198(10): 892-906, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35612598

RESUMEN

PURPOSE: The prognosis for glioblastoma patients remains dismal despite intensive research on better treatment options. Molecular and immunohistochemical markers are increasingly being investigated as understanding of their role in disease progression grows. O(6)-methylguanine-DNA methyltransferase (MGMT) promoter methylation has been shown to have prognostic and therapeutic relevance for glioblastoma patients. Other markers implicated in tumor formation and/or malignancy are p53, Alpha thalassemia/mental retardation syndrome X-linked (ATRX), Epidermal Growth Factor Receptor splice variant III (EGFRvIII), and Ki-67, with loss of nuclear ATRX expression and lower Ki-67 index being associated with prolonged survival. For p53 and EGFRvIII the data are contradictory. Our aim was to investigate the markers mentioned above regarding progression-free (PFS) and overall survival (OS) to evaluate their viability as independent prognostic markers for our patient collective. METHODS: In this retrospective study, we collected data on patients undergoing radiotherapy due to isocitrate dehydrogenase (IDH) wildtype glioblastoma at a single university hospital between 2014 and 2020. RESULTS: Our findings confirm Ki-67 labeling index ≤ 20% as an independent prognostic factor for prolonged PFS as well as MGMT promoter methylation for both prolonged PFS and OS, in consideration of age and Eastern Cooperative Oncology Group (ECOG) status, chemotherapy treatment, and total radiation dose for PFS as well as additionally sex, resection status, and receipt of treatment for progression or recurrence for OS. Additionally, Ki-67 labeling index ≤ 20% showed a significant correlation with prolonged OS in univariate analysis. Modification of the recursive partitioning analysis (RPA) score to include Ki-67 labeling index resulted in a classification with the possible ability to distinguish long-term-survivors from patients with unfavorable prognosis. CONCLUSION: MGMT promoter methylation and Ki-67 labeling index were independent predictors of survival in our collective. We see further studies pooling patient collectives to reach larger patient numbers concerning Ki-67 labeling index as being warranted.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/terapia , Quimioradioterapia , Metilación de ADN , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Receptores ErbB/genética , Receptores ErbB/metabolismo , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Isocitrato Deshidrogenasa/genética , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , O(6)-Metilguanina-ADN Metiltransferasa/genética , O(6)-Metilguanina-ADN Metiltransferasa/metabolismo , O(6)-Metilguanina-ADN Metiltransferasa/uso terapéutico , Pronóstico , Estudios Retrospectivos , Proteína p53 Supresora de Tumor/metabolismo
5.
Strahlenther Onkol ; 198(5): 427-435, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34523017

RESUMEN

PURPOSE: Purpose of this study was to investigate overall survival in recurrent glioblastoma treated with either carbon ion reirradiation or photon reirradiation. MATERIALS AND METHODS: In this retrospective study we evaluated 78 consecutive patients with recurrent IDH (Isocitrate dehydrogenase)-wildtype glioblastoma (38 patients carbon ion re-radiotherapy, 40 patients photon re-radiotherapy) treated with either carbon ion reirradiation or stereotactic photon reirradiation. 45 Gy (RBE; 15 fractions) carbon ion reirradiation (CIRT) or 39 Gy (13 fractions) photon reirradiation (FSRT) was administered, respectively. Overall survival was investigated with respect to histological, clinical, and epidemiological features. Kaplan-Meier and multivariate Cox statistics were calculated. A propensity score-matched analysis of the FSRT and CIRT groups using variables from a validated prognosis score was carried out. RESULTS: The type of reirradiation (CIRT vs. FSRT) significantly influenced overall survival-8.0 months vs. 6.5 months (univariate: p = 0.046)-and remained an independent prognostic factor in multivariate analysis (p = 0.017). Propensity score-adjusted analysis with CIRT versus FSRT as the dependent variable yielded a significant overall survival advantage for the CIRT group (median OS 8.9 versus 7.2 months, p = 0.041, 1­year survival 29 versus 10%). Adverse events (AE) were evaluated for both subgroups. For the FSRT group no toxicity ≥ grade 4 occurred. For the CIRT subgroup no grade 5 AE occurred, but 1 patient developed a grade 4 radionecrosis. We encountered 4 grade 3 toxicities. One patient developed a zoster at the trunk, 2 progressed in their paresis, and 1 featured progressive dysesthesia. CONCLUSION: In conclusion, carbon ion treatment is a safe and feasible treatment option for recurrent glioblastoma. Due to the retrospective nature of the study and two different dose levels for CIRT or FSRT, the improved outcome in CIRT reirradiation might be an effect of higher biological impact from carbon ions or a simple dose-escalation effect. This hypothesis needs prospective testing in larger patient cohorts. A prospective phase III randomized trial is in preparation at our center.


Asunto(s)
Glioblastoma , Reirradiación , Carbono , Glioblastoma/radioterapia , Humanos , Iones , Recurrencia Local de Neoplasia , Estudios Prospectivos , Estudios Retrospectivos
6.
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
7.
Strahlenther Onkol ; 196(12): 1096-1102, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-33125504

RESUMEN

PURPOSE: The coronavirus pandemic is affecting global health systems, endangering daily patient care. Hemato-oncological patients are particularly vulnerable to infection, requiring decisive recommendations on treatment and triage. The aim of this survey amongst experts on radiation therapy (RT) for lymphoma and leukemia is to delineate typical clinical scenarios and to provide counsel for high-quality care. METHODS: A multi-item questionnaire containing multiple-choice and free-text questions was developed in a peer-reviewed process and sent to members of the radiation oncology panels of the German Hodgkin Study Group and the German Lymphoma Alliance. Answers were assessed online and analyzed centrally. RESULTS: Omission of RT was only considered in a minority of cases if alternative treatment options were available. Hypofractionated regimens and reduced dosages may be used for indolent lymphoma and fractures due to multiple myeloma. Overall, there was a tendency to shorten RT rather than to postpone or omit it. Even in case of critical resource shortage, panelists agreed to start emergency RT for typical indications (intracranial pressure, spinal compression, superior vena cava syndrome) within 24 h. Possible criteria to consider for patient triage are the availability of (systemic) options, the underlying disease dynamic, and the treatment rationale (curative/palliative). CONCLUSION: RT for hemato-oncological patients receives high-priority and should be maintained even in later stages of the pandemic. Hypofractionation and shortened treatment schedules are feasible options for well-defined constellations, but have to be discussed in the clinical context.


Asunto(s)
COVID-19/epidemiología , Linfoma/radioterapia , Mieloma Múltiple/radioterapia , Pandemias , Oncología por Radiación/normas , SARS-CoV-2/aislamiento & purificación , Triaje/normas , Citas y Horarios , COVID-19/complicaciones , COVID-19/diagnóstico , COVID-19/prevención & control , Prueba de COVID-19 , Infección Hospitalaria/prevención & control , Diagnóstico Diferencial , Fraccionamiento de la Dosis de Radiación , Humanos , Higiene/normas , Control de Infecciones/métodos , Control de Infecciones/normas , Linfoma/complicaciones , Linfoma/tratamiento farmacológico , Mieloma Múltiple/complicaciones , Osteólisis/etiología , Osteólisis/radioterapia , Equipo de Protección Personal , Oncología por Radiación/métodos , Neumonitis por Radiación/diagnóstico , Síndrome de la Vena Cava Superior/etiología , Síndrome de la Vena Cava Superior/radioterapia , Encuestas y Cuestionarios , Tiempo de Tratamiento , Irradiación Corporal Total
8.
Radiat Oncol ; 14(1): 157, 2019 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-31477141

RESUMEN

Radiotherapy is frequently used in the therapy of lymphoma. Since lymphoma, for example Hodgkin's disease, frequently affect rather young patients, the induction of secondary cancer or other long-term adverse effects after irradiation are important issues to deal with. Especially for mediastinal manifestations numerous organs and substructures at risk play a role. The heart, its coronary vessels and cardiac valves, the lungs, the thyroid and, for female patients, the breast tissue are only the most important organs at risk. In this study we investigated if proton-radiotherapy might reduce the dose delivered to the organs at risk and thus minimize the therapy-associated toxicity. METHODS: In this work we compared the dose delivered to the heart, its coronary vessels and valves, the lungs, the thyroid gland and the breast tissue by different volumetric photon plans and a proton plan, all calculated for a dose of 28.8 Gy (EURO-NET-PHL-C2). Target Volumes have been defined by F18-FDG PET-positive areas, following a modified involved node approach. Data from ten young female patients with mediastinal lymphoma have been evaluated. Three different modern volumetric IMRT (VMAT) photon plans have been benchmarked against each other and against proton-irradiation concepts. For plan-evaluation conformity- and homogeneity-indices have been calculated as suggested in ICRU 83. The target volume coverage as well as the dose to important organs at risk as the heart with its substructures, the lungs, the breast tissue, the thyroid and the spinal cord were calculated and compared. For statistical evaluation mean doses to organs at risk were evaluated by non- parametric Kruskal-Wallis calculations with pairwise comparisons. RESULTS: Proton-plans and three different volumetric photon-plans have been calculated. Proton irradiation results in significant lower doses delivered to organ at risk. The median doses and the mean doses could be decreased while PTV coverage is comparable. As well conformity as homogeneity are slightly better for proton plans. For several organs a risk reduction for secondary malignancies has been calculated using literature data as reference. According to the used data derived from literature especially the secondary breast cancer risk, the secondary lung cancer risk and the risk for ischemic cardiac insults can be reduced significantly by using protons for radiotherapy of mediastinal lymphomas. CONCLUSION: Irradiation with protons for mediastinal Hodgkin-lymphoma results in significant lower doses for almost all organs at risk and is suitable to reduce long term side effects for pediatric and adolescent patients.


Asunto(s)
Mama/efectos de la radiación , Corazón/efectos de la radiación , Enfermedad de Hodgkin/radioterapia , Pulmón/efectos de la radiación , Terapia de Protones/métodos , Planificación de la Radioterapia Asistida por Computador/métodos , Glándula Tiroides/efectos de la radiación , Adolescente , Niño , Femenino , Humanos , Órganos en Riesgo/efectos de la radiación , Pronóstico , Dosificación Radioterapéutica
9.
Strahlenther Onkol ; 193(2): 100-108, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27678010

RESUMEN

INTRODUCTION: Field design changed substantially from extended-field RT (EF-RT) to involved-field RT (IF-RT) and now to involved-node RT (IN-RT) and involved-site RT (IS-RT) as well as treatment techniques in radiotherapy (RT) of Hodgkin's lymphoma (HL). The purpose of this article is to demonstrate the establishment of a quality assurance program (QAP) including modern RT techniques and field designs within the German Hodgkin Study Group (GHSG). METHODS: In the era of modern conformal RT, this QAP had to be fundamentally adapted and a new evaluation process has been intensively discussed by the radiotherapeutic expert panel of the GHSG. RESULTS: The expert panel developed guidelines and criteria to analyse "modern" field designs and treatment techniques. This work is based on a dataset of 11 patients treated within the sixth study generation (HD16-17). CONCLUSION: To develop a QAP of "modern RT", the expert panel defined criteria for analysing current RT procedures. The consensus of a modified QAP in ongoing and future trials is presented. With this schedule, the QAP of the GHSG could serve as a model for other study groups.


Asunto(s)
Adhesión a Directriz/estadística & datos numéricos , Enfermedad de Hodgkin/epidemiología , Enfermedad de Hodgkin/radioterapia , Guías de Práctica Clínica como Asunto , Garantía de la Calidad de Atención de Salud/estadística & datos numéricos , Oncología por Radiación/normas , Radioterapia Conformacional/normas , Alemania/epidemiología , Adhesión a Directriz/normas , Humanos , Prevalencia , Radioterapia Conformacional/estadística & datos numéricos , Factores de Riesgo , Integración de Sistemas , Resultado del Tratamiento
10.
Strahlenther Onkol ; 193(2): 109-115, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27596217

RESUMEN

INTRODUCTION: As part of the foundation of the German Hodgkin Study Group (GHSG) in 1978, a central radiotherapy (RT) reference centre was established to evaluate and to improve the quality of treatment. During the study generations, the quality assurance programs (QAP) were continued and adapted to the demands of each study. The purpose of this article is to demonstrate the results of the fifth study generation and to compare them to the previous findings. METHODS: With the start of the fourth GHSG study generation (HD10-12), a central prospective review of all diagnostic images was established to create an individual treatment plan for each early stage study patient. The quality of involved field RT was retrospectively evaluated by an expert panel of radiation oncologists. In the fifth study generation (HD13-15), the retrospective review of radiotherapy performed was refined and the results were compared with the findings of the fourth generation. RESULTS: The expert panel analyzed the RT planning and application of 1037 (28 %) patients (HD13 n = 465, HD14 n = 572). Simulation films were available in 85 % of cases and verification films in 87 %. RT was assessed as major violation in 46 % (HD13 = 38 %, HD14 = 52 %), minor violation in 9 % (HD13 = 9 %, HD14 = 9 %) and according to the protocol in 45 % (HD13 = 52 %, HD14 = 38 %). CONCLUSION: The value for QAP of RT within the GHSG trials is well known. Still there were several protocol violations. In the future, the QAP program has to be adapted to the requirements of "modern RT" in malignant lymphoma.


Asunto(s)
Adhesión a Directriz/estadística & datos numéricos , Enfermedad de Hodgkin/epidemiología , Enfermedad de Hodgkin/radioterapia , Guías de Práctica Clínica como Asunto , Garantía de la Calidad de Atención de Salud/estadística & datos numéricos , Radioterapia Conformacional/normas , Alemania/epidemiología , Adhesión a Directriz/normas , Humanos , Prevalencia , Oncología por Radiación/normas , Radioterapia Conformacional/estadística & datos numéricos , Factores de Riesgo , Integración de Sistemas , Resultado del Tratamiento
11.
Phys Med Biol ; 59(12): 3019-40, 2014 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-24842293

RESUMEN

In carbon ion beams, biological effects vary along the ion track; hence, to quantify them, specific radiobiological models are needed. One of them, the local effect model (LEM), in particular version I (LEM I), is implemented in treatment planning systems (TPS) clinically used in European particle therapy centers. From the physical properties of the specific ion radiation, the LEM calculates the survival probabilities of the cell or tissue type under study, provided that some determinant input parameters are initially defined. Mathematical models can be used to predict, for instance, the tumor control probability (TCP), and then evaluate treatment outcomes. This work studies the influence of the LEM I input parameters on the TCP predictions in the specific case of prostate cancer. Several published input parameters and their combinations were tested. Their influence on the dose distributions calculated for a water phantom and for a patient geometry was evaluated using the TPS TRiP98. Changing input parameters induced clinically significant modifications of the mean dose (up to a factor of 3.5), spatial dose distribution, and TCP predictions (up to factor of 2.6 for D50). TCP predictions were found to be more sensitive to the parameter threshold dose (Dt) than to the biological parameters α and ß. Additionally, an analytical expression was derived for correlating α, ß and Dt, and this has emphasized the importance of [Formula: see text]. The improvement of radiobiological models for particle TPS will only be achieved when more patient outcome data with well-defined patient groups, fractionation schemes and well-defined end-points are available.


Asunto(s)
Modelos Biológicos , Neoplasias de la Próstata/radioterapia , Dosis de Radiación , Humanos , Masculino , Probabilidad , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador
12.
Strahlenther Onkol ; 190(5): 433-43, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24595416

RESUMEN

BACKGROUND: A number of national and international societies published recommendations regarding the required equipment and manpower assumed to be necessary to treat a number of patients with radiotherapy. None of these recommendations were based on actual time measurements needed for specific radiotherapy procedures. The German Society of Radiation Oncology (DEGRO) was interested in substantiating these recommendations by prospective evaluations of all important core procedures of radiotherapy in the most frequent cancers treated by radiotherapy. The results of the examinations of radiotherapy with intensity-modulated radiation therapy (IMRT) in patients with different tumor entities are presented in this manuscript. PATIENTS, MATERIAL, AND METHODS: Four radiation therapy centers [University Hospital of Marburg, University Hospital of Giessen, University Hospital of Berlin (Charité), Klinikum rechts der Isar der Technischen Universität München] participated in this prospective study. The workload of the different occupational groups and room occupancies for the core procedures of radiotherapy were prospectively documented during a 2-month period per center and subsequently statistically analyzed. RESULTS: The time needed per patient varied considerably between individual patients and between centers for all the evaluated procedures. The technical preparation (contouring of target volume and organs at risk, treatment planning, and approval of treatment plan) was the most time-consuming process taking 3 h 54 min on average. The time taken by the medical physicists for this procedure amounted to about 57%. The training part of the preparation time was 87% of the measured time for the senior physician and resident. The total workload for all involved personnel comprised 74.9 min of manpower for the first treatment, 39.7 min for a routine treatment with image guidance, and 22.8 min without image guidance. The mean room occupancy varied between 10.6 min (routine treatment without image guidance) and 23.7 min (first treatment with image guidance). CONCLUSION: The prospective data presented here allow for an estimate of the required machine time and manpower needed for the core procedures of radiotherapy in an average radiation treatment with IMRT. However, one should be aware that a number of necessary and time-consuming activities were not evaluated in the present study.


Asunto(s)
Conducta Cooperativa , Difusión de Innovaciones , Recursos en Salud/normas , Comunicación Interdisciplinaria , Garantía de la Calidad de Atención de Salud/normas , Oncología por Radiación/normas , Radioterapia/normas , Estudios de Tiempo y Movimiento , Alemania , Recursos en Salud/estadística & datos numéricos , Hospitales Universitarios , Humanos , Estudios Prospectivos , Radioterapia/estadística & datos numéricos , Planificación de la Radioterapia Asistida por Computador , Sociedades Médicas , Recursos Humanos , Carga de Trabajo/estadística & datos numéricos
13.
Strahlenther Onkol ; 190(3): 310-6, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24424625

RESUMEN

PURPOSE: On the basis of correct Hounsfield unit to electron density calibration, cone-beam computed tomography (CBCT) data provide the opportunity for retrospective dose recalculation in the patient. Therefore, the consequences of translational positioning corrections and of morphological changes in the patient anatomy can be quantified for prostate cancer patients. MATERIALS AND METHODS: The organs at risk were newly contoured on the CBCT data sets of 7 patients so as to evaluate the actual applied dose. The daily dose to the planning target volume (PTV) was recalculated with and without the translation data, which result from the real patient repositioning. RESULTS: A CBCT-based dose recalculation with uncertainties less than 3 % is possible. The deviations between the planning CT and the CBCT without the translational positioning correction vector show an average dose difference of - 8 % inside the PTV. An inverse proportional relation between the mean bladder dose and the actual volume of the bladder could be established. The daily applied dose to the rectum is about 1-54 % higher than predicted by the planning CT. CONCLUSION: A dose calculation based on CBCT data is possible. The daily positioning correction of the patient is necessary to avoid an underdosage in the PTV. The new contouring of the organs at risk - the bladder and rectum - allows a better appraisal to be made of the total applied dose to these organs.


Asunto(s)
Tomografía Computarizada de Haz Cónico/métodos , Fraccionamiento de la Dosis de Radiación , Órganos en Riesgo , Neoplasias de la Próstata/radioterapia , Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Guiada por Imagen/métodos , Recto/efectos de la radiación , Vejiga Urinaria/efectos de la radiación , Calibración , Tomografía Computarizada de Haz Cónico/instrumentación , Humanos , Masculino , Posicionamiento del Paciente/instrumentación , Posicionamiento del Paciente/métodos , Fantasmas de Imagen , Dosificación Radioterapéutica , Planificación de la Radioterapia Asistida por Computador/instrumentación , Radioterapia Guiada por Imagen/instrumentación , Estudios Retrospectivos
14.
Strahlenther Onkol ; 190(2): 138-48, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24408057

RESUMEN

PURPOSE: The QUIRO study aimed to establish a secure level of quality and innovation in radiation oncology. Over 6 years, 27 specific surveys were conducted at 24 radiooncological departments. In all, 36 renowned experts from the field of radiation oncology (mostly head physicians and full professors) supported the realization of the study. METHODS: A salient feature of the chosen methodological approach is the "process" as a means of systematizing diversified medical-technical procedures according to standardized criteria. On the one hand, "processes" as a tool of translation are adapted for creating and transforming standards into concrete clinical and medical actions; on the other hand, they provide the basis for standardized instruments and methods to determine the required needs of physicians, staff, and equipment. In the foreground of the collection and measurement of resource requirements were the processes of direct service provision which were subdivided into modules for reasons of clarity and comprehensibility. Overhead tasks (i.e., participation in quality management) were excluded from the main study and examined in a separate survey with appropriate methods. RESULTS: After the exploration of guidelines, tumor- or indication-specific examination and treatment processes were developed in expert workshops. Moreover, those specific modules were defined which characterize these entities and indications in a special degree. Afterwards, these modules were compiled according to their time and resources required in the "reference institution", i.e., in specialized and as competent recognized departments (mostly from the university area), by various suitable survey methods. CONCLUSION: The significance of the QUIRO study and the validity of the results were optimized in a process of constant improvements and comprehensive checks. As a consequence, the QUIRO study yields representative results concerning the resource requirement for specialized, qualitatively and technologically highly sophisticated radiooncologic treatment in Germany.


Asunto(s)
Difusión de Innovaciones , Garantía de la Calidad de Atención de Salud/métodos , Garantía de la Calidad de Atención de Salud/normas , Oncología por Radiación/métodos , Oncología por Radiación/normas , Alemania , Recursos en Salud/normas , Necesidades y Demandas de Servicios de Salud/normas , Investigación sobre Servicios de Salud/métodos , Investigación sobre Servicios de Salud/normas , Encuestas Epidemiológicas/métodos , Encuestas Epidemiológicas/normas , Humanos , Programas Nacionales de Salud/normas , Radioterapia/métodos , Radioterapia/normas
15.
Phys Med Biol ; 58(12): 3979-93, 2013 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-23685746

RESUMEN

Scanned ion beam delivery enables the highest degree of target dose conformation attainable in external beam radiotherapy. Nominal pencil beam widths (spot sizes) are recorded during treatment planning system commissioning. Due to changes in the beam-line optics, the actual spot sizes may differ from these commissioning values, leading to differences between planned and delivered dose. The purpose of this study was to analyse the dosimetric consequences of spot size variations in particle therapy treatment plans. For 12 patients with skull base tumours and 12 patients with prostate carcinoma, scanned-beam carbon ion and proton treatment plans were prepared and recomputed simulating spot size changes of (1) ±10% to simulate the typical magnitude of fluctuations, (2) ±25% representing the worst-case scenario and (3) ±50% as a part of a risk analysis in case of fault conditions. The primary effect of the spot size variation was a dose deterioration affecting the target edge: loss of target coverage and broadening of the lateral penumbra (increased spot size) or overdosage and contraction of the lateral penumbra (reduced spot size). For changes ≤25%, the resulting planning target volume mean 95%-isodose line coverage (CI-95%) deterioration was ranging from negligible to moderate. In some cases changes in the dose to adjoining critical structures were observed.


Asunto(s)
Planificación de la Radioterapia Asistida por Computador/métodos , Radioterapia Asistida por Computador/métodos , Humanos , Masculino , Neoplasias de la Próstata/radioterapia , Radiometría , Neoplasias de la Base del Cráneo/radioterapia
16.
Phys Med Biol ; 57(22): 7261-74, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23075883

RESUMEN

Biological optimization for treatment planning in carbon ion therapy is currently based on the first version of the local effect model (LEM I). Further developments implemented in the latest version (LEM IV) allowed to predict more accurately the Relative Biological Effectiveness (RBE) in-vitro. The main goal of this study is to compare the LEM IV against LEM I under treatment-like conditions for idealized target geometries. Therefore, physical dose distributions resulting from the biological optimization with LEM I were used to recalculate the RBE-weighted dose distribution based on LEM IV. Input parameters representing the clinical endpoints late toxicity in the central nervous system and the tumor control for chordoma were chosen to investigate the impact of changes on the predicted isoeffective dose levels. The recalculated RBE-weighted dose distributions show an increase within the target region, and the mean RBE-weighted dose values are dependent on the geometry and decrease with increasing target dimension. The differences between predictions of LEM IV and LEM I are less than 10% for typical tumor volumes treated in the pilot project at GSI. Median RBE-weighted doses predicted by LEM IV in the target region are consistent with clinically observed dose-response behavior as demonstrated by comparison to the 5-year local control curve for skull base chordoma.


Asunto(s)
Carbono/uso terapéutico , Planificación de la Radioterapia Asistida por Computador/métodos , Humanos , Dosificación Radioterapéutica , Efectividad Biológica Relativa
17.
Strahlenther Onkol ; 188(9): 769-76, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22847518

RESUMEN

BACKGROUND: The German Society of Radiation Oncology ("Deutsche Gesellschaft für Radioonkologie", DEGRO) initiated a multicenter trial to develop and evaluate adequate modules to assert core processes and subprocesses in radiotherapy. The aim of this prospective evaluation was to methodical assess the required resources (technical equipment and medical staff) for stereotactic radiotherapy/radiosurgery. MATERIAL AND METHODS: At two radiotherapy centers of excellence (University Hospitals of Heidelberg and Marburg/Giessen), the manpower and time required for the implementation of intra- and extracranial stereotactic radiotherapy was prospectively collected consistently over a 3-month period. The data were collected using specifically developed process acquisition tools and standard forms and were evaluated using specific process analysis tools. RESULTS: For intracranial (extracranial) fractionated stereotactic radiotherapy (FSRT) and radiosurgery (RS), a total of 1,925 (270) and 199 (36) records, respectively, could be evaluated. The approximate time needed to customize the immobilization device was median 37 min (89 min) for FRST and 31 min (26 min) for RS, for the contrast enhanced planning studies 22 and 27 min (25 and 28 min), for physical treatment planning 122 and 59 min (187 and 27 min), for the first and routine radiotherapy sessions for FSRT 40 and 13 min (58 and 31 min), respectively. The median time needed for the RS session was 58 min (45 min). The corresponding minimal manpower needed was 2 technicians for customization of the immobilization device, 2.5 technicians and 1 consultant for the contrast-enhanced planning studies, 1 consultant, 0.5 resident and 0.67 medical physics expert (MPE) for physical treatment planning, as well as 1 consultant, 0.5 resident, and 2.5 technicians for the first radiotherapy treatment and 2.33 technicians for routine radiotherapy sessions. CONCLUSION: For the first time, the resource requirements for a radiotherapy department for the maintenance, protection and optimization of operational readiness for the application of intra- and extracranial stereotactic radiotherapy was determined methodically.


Asunto(s)
Fuerza Laboral en Salud/estadística & datos numéricos , Cuerpo Médico de Hospitales/estadística & datos numéricos , Admisión y Programación de Personal/estadística & datos numéricos , Radiocirugia/estadística & datos numéricos , Estudios de Tiempo y Movimiento , Carga de Trabajo/estadística & datos numéricos , Alemania , Humanos
18.
Herz ; 36(4): 311-24, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21633806

RESUMEN

Radiation therapy, which has become an integral part of modern treatment strategies for many types of cancer in recent decades, is associated with the risk of long-term adverse effects. Particularly in the case of patients with a good prognosis as a result of these modern treatment modalities, avoiding therapy-related side effects plays an increasingly important role. Of these side effects, cardiac complications are particularly relevant since they not only adversely affect quality of life but can also be potentially life-threatening. This review summarizes and critically analyzes the available evidence on the impact of ionizing irradiation on the cardiovascular system. The paper presents an overview of the current knowledge on epidemiological evidence, clinical presentation and risk factors of radiation-induced cardiovascular disease. Additionally, mechanisms of development of this type of complication and strategies for screening, treatment, and avoiding cardiac complications are discussed.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Neoplasias/radioterapia , Traumatismos por Radiación/etiología , Traumatismos por Radiación/prevención & control , Radiofármacos/efectos adversos , Radioterapia Conformacional/efectos adversos , Humanos , Neoplasias/complicaciones
19.
Ann Oncol ; 21(11): 2284-2289, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20427347

RESUMEN

BACKGROUND: Cetuximab is active in the treatment of squamous cell carcinoma of the head and neck (SCCHN), enhancing both radiotherapy and chemotherapy effects. This phase I study was designed to investigate the safety and tolerability of combining weekly cisplatin treatment with cetuximab and hyperfractionated-accelerated radiotherapy (HART) for locally advanced SCCHN. PATIENTS AND METHODS: Patients with unresectable stage III or IVA/B SCCHN were treated with cetuximab, 400 mg/m² initial dose on day -7 of HART, followed by 250 mg/m² weekly during the administration of HART, which started with 2.0 Gy/day (5 days/week) for 3 weeks followed by 1.4 Gy/twice-daily (Monday to Friday) for another 3 weeks, resulting in a total dose of 70.6 Gy. Cisplatin was administered weekly starting on the first day of radiotherapy until week 6. Cisplatin was dose escalated of four dose levels from 20 to 40 mg/m² using a classical 3 + 3 dose escalation algorithm. RESULTS: Eighteen patients were enrolled. Sixteen patients were eligible for toxicity, and 15 for response. No maximum tolerated dose was reached for cisplatin. One of six patients of dose level 4 had grade 4 neutropenia. This patient died 1 week after the end of the study treatment. The most common types of grade 3+ adverse events were mucositis (9 of 16 patients), in-field dermatitis (6 of 16 patients) and neutropenia (4 of 16 patients). Cetuximab-related hypersensitivity was observed in 1 out of 18 patients. Six weeks after the end of the study treatment, 5 complete responses, 8 partial responses and 1 progressive disease (at distant sites) were documented in a total of 15 patients (objective response rate 87%). CONCLUSIONS: The combination of cisplatin with cetuximab and HART is active, well tolerated and merits additional investigation. The recommended weekly dose of cisplatin for phase II studies is 40 mg/m².


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Neoplasias de Cabeza y Cuello/radioterapia , Adulto , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales Humanizados , Carcinoma de Células Escamosas/patología , Cetuximab , Cisplatino/administración & dosificación , Terapia Combinada , Fraccionamiento de la Dosis de Radiación , Relación Dosis-Respuesta a Droga , Femenino , Neoplasias de Cabeza y Cuello/patología , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Prospectivos , Tasa de Supervivencia , Resultado del Tratamiento
20.
Anticancer Res ; 29(7): 2645-53, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19596941

RESUMEN

BACKGROUND: Definitive chemoradiation is a well-established option in the treatment of locally advanced squamous cell carcinoma of the head and neck. The intention of this study was to evaluate its efficacy on cervical lymph node metastases in a prospective study after a standardized protocol for chemoradiation (CRT) and histopathological evaluation, respectively. PATIENTS AND METHODS: The data of 25 patients (10 oropharynx, 15 hypopharynx) who received planned neck dissection after definitive chemoradiation for UICC stage IV carcinomas of the pharynx were analyzed. All patients were sonomorphologically staged positive for lymph nodes (3 patients: N1; 2 patients N2a; 7 patients N2b; 9 patients N2c and 4 patients N3). A neck dissection was carried out 8.9+/-1.5 weeks (range 6-13) post treatment. The specimens obtained from the different neck levels were histologically examined for viable tumour cells. RESULTS: Local control was achieved in 100% of all patients on endoscopy 9 weeks after the chemoradiation. In 14/25 patients (56%), still viable tumour tissue was found in the neck dissection (ND) specimen. Only one of these 14 patients (7%) was deemed suspicious for residual lymphadenopathy from clinical and diagnostic findings at re-staging after chemoradiation, the others were staged yN0. Postsurgical complications occurred in six patients (24%) such as bleeding and prolonged wound healing in one patient each and functional deficits in an additional four patients. One patient developed a scar recurrence seven months after surgery. CONCLUSION: Based on these findings, the ultimate efficacy of primary CRT should not be judged 8-10 weeks after the treatment. Therefore planned neck dissection should be performed no earlier than 12 weeks after primary CRT.


Asunto(s)
Antineoplásicos/uso terapéutico , Cuello/cirugía , Neoplasias Faríngeas/terapia , Adulto , Anciano , Terapia Combinada , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Faríngeas/tratamiento farmacológico , Neoplasias Faríngeas/radioterapia , Neoplasias Faríngeas/cirugía , Estudios Prospectivos
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