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1.
Klin Padiatr ; 227(3): 108-15, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25985445

RESUMO

Curative therapies for Ewing sarcoma have been developed within cooperative groups. Consecutive clinical trials have systematically assessed the impact and timing of local therapy and the activity of cytotoxic drugs and their combinations. They have led to an increase of long-term disease-free survival to around 70% in patients with localized disease. Translational research in ES remains an area in which interdisciplinary and international cooperation is essential for future progress. This article reviews current state-of-the art therapy, with a focus on trials performed in Europe, and summarizes novel strategies to further advance both the cure rates and quality of survival.


Assuntos
Neoplasias Ósseas/terapia , Comportamento Cooperativo , Comunicação Interdisciplinar , Sarcoma de Ewing/terapia , Neoplasias de Tecidos Moles/terapia , Protocolos de Quimioterapia Combinada Antineoplásica , Neoplasias Ósseas/mortalidade , Criança , Ensaios Clínicos como Assunto , Terapia Combinada , Progressão da Doença , Humanos , Terapia Neoadjuvante , Osteotomia , Radioterapia Adjuvante , Sarcoma de Ewing/mortalidade , Neoplasias de Tecidos Moles/mortalidade , Taxa de Sobrevida
2.
Strahlenther Onkol ; 190(2): 138-48, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24408057

RESUMO

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.


Assuntos
Difusão de Inovações , Garantia da Qualidade dos Cuidados de Saúde/métodos , Garantia da Qualidade dos Cuidados de Saúde/normas , Radioterapia (Especialidade)/métodos , Radioterapia (Especialidade)/normas , Alemanha , Recursos em Saúde/normas , Necessidades e Demandas de Serviços de Saúde/normas , Pesquisa sobre Serviços de Saúde/métodos , Pesquisa sobre Serviços de Saúde/normas , Inquéritos Epidemiológicos/métodos , Inquéritos Epidemiológicos/normas , Humanos , Programas Nacionais de Saúde/normas , Radioterapia/métodos , Radioterapia/normas
3.
Strahlenther Onkol ; 189(4): 308-14, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23443613

RESUMO

PURPOSE: The goal of the present work was to assess the potential advantage of intensity-modulated radiotherapy (IMRT) over three-dimensional conformal radiotherapy (3D-CRT) planning in pelvic Ewing's sarcoma. PATIENTS AND METHODS: A total of 8 patients with Ewing sarcoma of the pelvis undergoing radiotherapy were analyzed. Plans for 3D-CRT and IMRT were calculated for each patient. Dose coverage of the planning target volume (PTV), conformity and homogeneity indices, as well as further parameters were evaluated. RESULTS: The average dose coverage values for PTV were comparable in 3D-CRT and IMRT plans. Both techniques had a PTV coverage of V95 > 98 % in all patients. Whereas the IMRT plans achieved a higher conformity index compared to the 3D-CRT plans (conformity index 0.79 ± 0.12 vs. 0.54 ± 0.19, p = 0.012), the dose distribution across the target volumes was less homogeneous with IMRT planning than with 3D-CRT planning. This difference was statistically significant (homogeneity index 0.11 ± 0.03 vs. 0.07 ± 0.0, p = 0.035). For the bowel, Dmean and D1%, as well as V2 to V60 were reduced in IMRT plans. For the bladder and the rectum, there was no significant difference in Dmean. However, the percentages of volumes receiving at least doses of 30, 40, 45, and 50 Gy (V30 to V50) were lower for the rectum in IMRT plans. The volume of normal tissue receiving at least 2 Gy (V2) was significantly higher in IMRT plans compared with 3D-CRT, whereas at high dose levels (V30) it was significantly lower. CONCLUSION: Compared to 3D-CRT, IMRT showed significantly better results regarding dose conformity (p = 0.012) and bowel sparing at dose levels above 30 Gy (p = 0.012). Thus, dose escalation in the radiotherapy of pelvic Ewing's sarcoma can be more easily achieved using IMRT.


Assuntos
Neoplasias Ósseas/radioterapia , Ossos Pélvicos , Planejamento da Radioterapia Assistida por Computador/métodos , Radioterapia Conformacional/métodos , Radioterapia de Intensidade Modulada/métodos , Sarcoma de Ewing/radioterapia , Adolescente , Neoplasias Ósseas/patologia , Criança , Progressão da Doença , Feminino , Humanos , Masculino , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/radioterapia , Ossos Pélvicos/patologia , Ossos Pélvicos/efeitos da radiação , Lesões por Radiação/prevenção & controle , Dosagem Radioterapêutica , Reto/patologia , Reto/efeitos da radiação , Sarcoma de Ewing/patologia , Bexiga Urinária/patologia , Bexiga Urinária/efeitos da radiação
4.
Strahlenther Onkol ; 188 Suppl 3: 253-62, 2012 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-22895626

RESUMO

Technical and methodical developments have changed radiation oncology substantially over the last 40 years. Modern imaging methods, e.g., computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), and ultrasound (US), have not only improved the detection of tumors but have also become tools for computed treatment planning. Megavoltage irradiation with accelerators using photons and electrons with large and small fields, intensity modulation (IMRT), image-guided radiotherapy (IGRT), stereotactic irradiation and radiosurgery, intraoperative radiotherapy (IORT), and modern remote controlled afterloading brachytherapy have made high precision radiotherapy increasingly possible. Hadron therapy has potential for further developments. Radiation oncology today is an interdisciplinary modality and increasingly considers interactions with new drugs and differentiated surgical methods. There is a strong need for comprehensive evaluation of the new methods and also for translational research in biology of tumors and normal tissue biology as well as in medical physics and techniques.


Assuntos
Braquiterapia/história , Diagnóstico por Imagem/história , Neoplasias/história , Radioterapia (Especialidade)/história , Radiocirurgia/história , Planejamento da Radioterapia Assistida por Computador/história , Radioterapia de Intensidade Modulada/história , Alemanha , História do Século XX , História do Século XXI , Humanos
5.
Strahlenther Onkol ; 188(2): 113-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22241435

RESUMO

BACKGROUND AND PURPOSE: To conform to recommendations regarding the treatment of breast cancer, an estimation of costs and personnel to assure treatment is required. To date no recommendations based on real time measurements are available. The DEGRO (German Society of Radiation Oncology), therefore, initiated a prospective multicenter evaluation of core procedures of radiotherapy. In this analysis, the results regarding human resources and room occupation during the treatment of breast cancer are presented. PATIENTS AND METHODS: Three academic radiation oncology centers (Erlangen, Münster, Mannheim) prospectively documented their workflow and working time for all breast cancer patients from July-October 2008. Subsequently, a statistical analysis was performed. RESULTS: The longest working time of physicians was the definition of the target volume and organs at risk (mean 33 min). Furthermore, physicians needed much time for general tasks, which included conversations. Physicists needed the most time for treatment planning and authorization (64 min), whereas technicians were mostly needed in day-to-day radiotherapy treatment (15 min, 31 min including verification). Despite significant differences in specific steps between centers, overall working times and room occupation were comparable and representative. Special procedures (intraoperative radiotherapy/multicatheter brachytherapy) required considerable amounts of additional working time of physicians and physicists. CONCLUSION: In this prospective analysis, data of human resources and room occupation during treatment of breast cancer are presented for the first time. Each patient consumes about 12 h of human resources for treatment and 3.75 h for general tasks (physicians 4.7 h, physicists 1.8 h, and technicians 9.2 h).


Assuntos
Neoplasias da Mama/epidemiologia , Neoplasias da Mama/radioterapia , Radioterapia/estatística & dados numéricos , Alocação de Recursos/estatística & dados numéricos , Estudos de Tempo e Movimento , Carga de Trabalho/estatística & dados numéricos , Feminino , Alemanha/epidemiologia , Humanos , Prevalência
6.
Nuklearmedizin ; 46(6): 291-301, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-18084685

RESUMO

FDG-PET/CT examinations combine metabolic and morphologic imaging within an integrated procedure. Over the past decade PET/CT imaging has gained wide clinical acceptance in the field of oncology. This FDG-PET/CT guideline focuses on indications, data acquisition and processing as well as documentation of FDG-PET/CT examinations in oncologic patients within a clinical and social context specific to Germany. Background information and definitions are followed by examples of clinical and research applications of FDG-PET/CT. Furthermore, protocols for CT scanning (low dose and contrast-enhanced CT) and PET emission imaging are discussed. Documentation and reporting of examinations are specified. Image interpretation criteria and sources of errors are discussed. Quality control for FDG and PET/CT-systems, qualification requirements of personnel as well as legal aspects are presented.


Assuntos
Fluordesoxiglucose F18 , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/normas , Compostos Radiofarmacêuticos , Tomografia Computadorizada por Raios X/normas , Documentação , Humanos
7.
J Clin Oncol ; 17(4): 1185, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10561177

RESUMO

PURPOSE: The objective of this prospective study was to assess the feasibility, toxicity, and efficacy of an intensive trimodality approach in stage III non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Fifty-four patients with NSCLC and biopsy-proven N2 nodes (IIIA; n = 25) or N3 nodes or T4 lesions (IIIB; n = 29) were administered two initial cycles of ifosfamide, carboplatin, and etoposide; subsequent radiotherapy (45 Gy, twice-daily 1.5 Gy) with concurrent carboplatin and vindesine; and surgery if the patient's disease was resectable or conventional radiotherapy (16 Gy, 2 Gy/d) if the patient's disease was not resectable or incompletely resectable. RESULTS: Thirty-seven patients (69%) responded to preoperative induction. Forty of 54 patients (74%) had disease that was resectable, with 34 (63%) complete resections (R0). A substantial pathologic response (tumor regression [TR] > 90%) was achieved in 27 of 54 patients (50%) and is revealed as an independent predictor for long-term survival after surgery. Five treatment-related deaths (9%) occurred. With a median follow-up period of 44 months, calculated survival rates at 3 years were 35% for patients with stage IIIA disease, 26% for patients with stage IIIB disease, and 56% for patients with R0 disease and TR > 90%. CONCLUSION: This trimodality approach is feasible and results in encouraging 3-year survival rates in prognostically unfavorable patients with stage III NSCLC. Patients experiencing a 90% degree of pathologic TR were most likely to achieve long-term survival.


Assuntos
Carcinoma de Células Pequenas/terapia , Neoplasias Pulmonares/terapia , Adulto , Idoso , Antineoplásicos/uso terapêutico , Carcinoma de Células Pequenas/patologia , Distribuição de Qui-Quadrado , Terapia Combinada , Estudos de Viabilidade , Feminino , Humanos , Neoplasias Pulmonares/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Modelos de Riscos Proporcionais , Estudos Prospectivos , Dosagem Radioterapêutica , Análise de Sobrevida , Resultado do Tratamento
8.
J Clin Oncol ; 19(18): 3861-73, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11559724

RESUMO

PURPOSE: The study was initiated to obtain epidemiologic data and information on anatomic and histologic distribution, clinical features, and treatment results in patients with primary gastrointestinal non-Hodgkin's lymphomas (PGI NHL). PATIENTS AND METHODS: Between October 1992 and November 1996, 371 PGI NHL patients were eligible to evaluate clinical features. Radiotherapy and chemotherapy were stratified according to histologic grading, stage, and whether surgery had been carried out or not. RESULTS: A total of 74.8% patients had gastric NHL (PGL). Within the intestine, the small bowel and the ileocecal region were involved in 8.6% and 7.0% of the cases, respectively. Multiple GI involvement (MGI) was 6.5%. Approximately 90% of the GI NHL were in stages IE/IIE. Aggressive NHL accounted for the majority, with a distinguishable pattern in several sites. Forty percent of PGL were of low-grade mucosa-associated lymphatic tissue type. One third of large-cell lymphomas had low-grade components. Most intestinal NHL were germinal-center lymphomas. The site of origin was prognostic. In gastric and ileocecal lymphoma, event-free (EFS) and overall survival (OS) were significantly higher as compared with the small intestine or MGI (median time of observation, 51 months). In PGL, localized disease was prognostic for EFS and OS. Histologic grade influenced only EFS significantly. Numbers in intestinal lymphomas were too small for subanalyses. CONCLUSION: PGI NHL are heterogeneous diseases. The number of localized PGL allowed for detailed analyses. Larger studies are needed for stages III and IV and for intestinal NHL. A uniform reporting system for PGI NHL, in terms of definitions and histologic and staging classifications, is needed to facilitate comparison of treatment results.


Assuntos
Neoplasias Gastrointestinais/terapia , Linfoma não Hodgkin/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Gastrointestinais/patologia , Alemanha , Humanos , Linfoma não Hodgkin/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Sistema de Registros , Análise de Sobrevida
9.
J Clin Oncol ; 19(18): 3874-83, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11559725

RESUMO

PURPOSE: The aim of the study was to obtain data on anatomic and histologic distribution, clinical features, and treatment results of patients with primary gastrointestinal non-Hodgkin's lymphomas, particularly combined surgical and conservative treatment (CSCT) versus conservative treatment (CT) alone for primary gastric lymphoma (PGL) in localized stages. PATIENTS AND METHODS: Whether the treatment included surgery was left to the discretion of each participating center. Radiotherapy (Rx) and chemotherapy were stratified according to histologic grading, stage, and the inclusion or omission of surgery as follows: patients with low-grade PGL were treated with extended-field (EF) Rx (30 Gy). In case of residual tumor after surgery or in case of CT only (in stage IIE after six cycles of cyclophosphamide, vincristine, and prednisone), an additional boost of 10 Gy was given. All patients with high-grade PGL were treated with four (stage IE) or six (stage IIE) cycles of cyclophosphamide, doxorubicin, vincristine, and prednisone followed by EF Rx (stage IE) or involved-field (IF) Rx (stage IIE). Rx dosage corresponded to low-grade NHL. RESULTS: Between October 1992 and November 1996, 106 patients had CT only. The survival rate (SR) after 5 years was 84.4% and was influenced neither by patients' characteristics nor by stage or histologic grade. Seventy-nine patients had CSCT. Their SR was 82.0%. Complete resection of the tumor (R0) was prognostic for the overall survival (P =.0165) as compared with incomplete resection. CONCLUSION: Although the study was not randomized, a stomach-conserving approach may be favored.


Assuntos
Neoplasias Gastrointestinais/terapia , Linfoma não Hodgkin/terapia , Idoso , Idoso de 80 Anos ou mais , Feminino , Neoplasias Gastrointestinais/patologia , Neoplasias Gastrointestinais/cirurgia , Humanos , Linfoma não Hodgkin/patologia , Linfoma não Hodgkin/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Qualidade de Vida , Análise de Sobrevida
10.
J Clin Oncol ; 19(11): 2905-14, 2001 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-11387364

RESUMO

PURPOSE: To show that radiotherapy (RT) dose to the noninvolved extended field (EF) can be reduced without loss of efficacy in patients with early-stage Hodgkin's disease (HD). PATIENTS AND METHODS: During 1988 to 1994, pathologically staged patients with stage I or II disease who were without risk factors (large mediastinal mass, extranodal lesions, massive splenic disease, elevated erythrocyte sedimentation rate, or three or more involved areas) were recruited from various centers. All patients received 40 Gy total fractionated dose to the involved field areas but were randomly assigned to receive either 40 Gy (arm A) or 30 Gy (arm B) total fractionated dose for the clinically noninvolved EF. No chemotherapy was given. RT films were prospectively reviewed for protocol violations and recurrences retrospectively related to the applied RT. RESULTS: Of 382 recruited patients, 376 were eligible for randomized comparison, 190 in arm A and 186 in arm B. Complete remission was attained in 98% of patients in each arm. With a median follow-up of 86 months, 7-year relapse-free survival (RFS) rates were 78% (arm A) and 83% (arm B) (P =.093). The upper 95% confidence limit for the possible inferiority of arm B in RFS was 4%. Corresponding overall survival rates were 91% (arm A) and 96% (arm B) (P =.16). The most common causes of death (n = 27) were cardiorespiratory disease/pulmonary embolisms (seven), second malignancy (six), and HD (five). Protocol violation was associated with significantly poorer RFS. Nonirradiated nodes were involved in 42 of 52 reviewed relapses, infield areas in 18, marginal areas in 17, and extranodal sites in 16. CONCLUSION: EF-RT alone attains good survival rates in favorable early-stage HD. The 30-Gy dose is adequate for clinically noninvolved areas. Protocol violation worsens the subsequent prognosis. Relapse patterns suggest that systemic therapy can reduce the 20% long-term relapse rate.


Assuntos
Doença de Hodgkin/radioterapia , Radioterapia/métodos , Adolescente , Adulto , Idoso , Fracionamento da Dose de Radiação , Feminino , Doença de Hodgkin/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Prognóstico , Dosagem Radioterapêutica , Análise de Sobrevida , Resultado do Tratamento
11.
Anticancer Res ; 25(3A): 1671-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16033080

RESUMO

We report on the case of a 19-year-old male with an alpha-fetoprotein (AFP)-producing acinar cell carcinoma of the pancreas. Tumour markers other than AFP were normal. Because of inoperability, a combined radiochemotherapy was initiated with a hyperfractionated dose of 44.8 Gy. Initially, the tumour showed a good response to irradiation and 5-fluorouracil (5-FU) application, and therapy showed sufficient local control. After combined radio-chemotherapy, AFP levels declined from about 3000 ng/ml (reference area: 0-7 ng/ml) to 18 ng/ml, but increased when widespread metastasis appeared. The patient died 18 months after the initial therapy due to general tumour progression. Originally, AFP was thought to be specific to hepatocellular carcinoma and germ cell tumours. Rarely has it been reported in other malignancies. Rare cases of acinar cell carcinomas of the pancreas were found to express AFP. Our patient is the youngest reported in the literature to date. When present, AFP expression is useful for diagnosis and as a marker for monitoring therapeutic response and recurrence of the disease.


Assuntos
Neoplasias Pancreáticas/metabolismo , alfa-Fetoproteínas/metabolismo , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Humanos , Masculino , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/radioterapia , alfa-Fetoproteínas/biossíntese
12.
Nuklearmedizin ; 44(6): 229-34, 236-7, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16400382

RESUMO

AIM: For the examination of the impact on clinical practice of the guidelines for differentiated thyroid carcinoma (DTC), treatment data from the ongoing Multicenter Study Differentiated Thyroid Carcinoma (MSDS) were analyzed. PATIENTS, METHODS: Patients were randomized to adjuvant external beam radiotherapy (RTx) or no RTx in addition to standard therapy in TNM stages pT4 pN0/1/x M0/x (UICC, 5th ed. 1997). All patients were to receive the same treatment regimen consisting of thyroidectomy, ablative radioiodine therapy (RIT), and a diagnostic 131I whole-body scintigraphy (WBS) 3-4 months after RIT. RESULTS: Of 339 eligible patients enrolled between January 2000 and March 2004, 273 could be analyzed. Guideline recommendations by the German Society for Nuclear Medicine from 1999 and 1992 were complied with within 28% and 82% with regard to the interval between surgery and RIT (4 vs. 4-6 weeks), in 33% and 84% with regard to 131I activity for RIT (1-3 vs. 1-4 GBq; +/- 10%), and in 16% and 60% with regard to 131I activity for WBS (100-300 vs. 100-400 MBq; +/- 10%). CONCLUSIONS: The 1999 guideline revision appears to have had little impact on clinical practice. Further follow-up will reveal if guideline compliance had an effect on outcomes.


Assuntos
Fidelidade a Diretrizes , Radioisótopos do Iodo/uso terapêutico , Guias de Prática Clínica como Assunto , Radioterapia/normas , Neoplasias da Glândula Tireoide/radioterapia , Terapia Combinada , Humanos , Radioisótopos do Iodo/normas , Estudos Prospectivos , Compostos Radiofarmacêuticos/normas , Compostos Radiofarmacêuticos/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Neoplasias da Glândula Tireoide/cirurgia
13.
Int J Radiat Oncol Biol Phys ; 42(3): 617-22, 1998 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-9806523

RESUMO

PURPOSE: Restenosis after catheter-based revascularization has been demonstrated to be primarily caused by smooth muscle cell proliferation. This study examines the effects of external beam irradiation on neointimal proliferation after external injury to the central artery of the rabbit ear. METHODS AND MATERIALS: Thirty male New Zealand White rabbits were used in this study. Crush lesions were performed on each ear under general anesthesia and bilateral auricular nerve blockade. A single dose of 1200 cGy (n = 10), 1600 cGy (n = 10), or 2000 cGy (n = 10) gamma radiation was delivered to the left or right central artery of the ear 24 hours after injury; the contralateral central artery served as control. All rabbits were sacrificed after 21 days and the central arteries of both ears were fixed for morphometric measurements. RESULTS: Mean (+/-SD) neointimal area was 0.062 +/- 0.005 mm2 (1200 cGy), 0.022 +/- 0.005 mm2 (1600 cGy), and 0.028 +/- 0.006 mm2 in irradiated arteries compared with 0.081 +/- 0.009 mm2 in the control group. Mean (+/-SD) luminal area was 0.049 +/- 0.004 mm2 (1200 cGy), 0.059 +/- 0.002 mm2 (1600 cGy), and 0.072 +/- 0.006 mm2 (2000 cGy) in irradiated arteries compared with 0.043 +/- 0.008 mm2 in the control group. The differences in neointimal and luminal area between control and irradiated arteries were significant (p < 0.05) for the 1600 and 2000 cGy group only. CONCLUSION: We conclude that in this model, external beam X-ray irradiation was successful in reducing neointimal proliferation after injury of the central artery of the rabbit ear. Marked reductions in neointimal proliferation were demonstrated in vessels subject to 1600 and 2000 cGy radiation; a less prominent effect was noted for 1200 cGy. Whether this approach can be used successfully to inhibit restenosis in the clinical setting requires further investigation.


Assuntos
Músculo Liso Vascular/patologia , Músculo Liso Vascular/efeitos da radiação , Túnica Íntima/patologia , Túnica Íntima/efeitos da radiação , Animais , Raios gama/uso terapêutico , Hiperplasia/prevenção & controle , Masculino , Músculo Liso Vascular/lesões , Coelhos , Doses de Radiação
14.
Int J Radiat Oncol Biol Phys ; 12(3): 397-9, 1986 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2420771

RESUMO

Between 1982 and 1983, 32 patients were treated for locally advanced inoperable squamous cell carcinoma (SCC) of the head and neck in a prospective pilot study. Patients received two to five courses of chemotherapy consisting of methotrexate, bleomycin and cis-dichlorodiammine-platinum (II). Radical radiotherapy was performed two weeks after administration of chemotherapy. Despite the high initial response rate to chemotherapy of 62.5%, long-term results remained poor. After a median follow-up of 10.5 months (3-39 months), 15 patients were still alive, but only 4 were clinically free of disease. Aggressive chemotherapy does not prevent delivery of full-dose radiotherapy for SCC of the head and neck. Furthermore, our study does not suggest that chemotherapy has a great influence on long-term results.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeça e Pescoço/terapia , Adulto , Idoso , Bleomicina/administração & dosagem , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Cisplatino/administração & dosagem , Terapia Combinada , Esquema de Medicação , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Estudos Prospectivos
15.
Int J Radiat Oncol Biol Phys ; 47(4): 1033-42, 2000 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-10863076

RESUMO

PURPOSE: The lung is the major dose-limiting organ for radiotherapy of cancer in the thoracic region. The pathogenesis of radiation-induced lung injury at the molecular level is still unclear. Immediate cellular damage after irradiation is supposed to result in cytokine-mediated multicellular interactions with induction and progression of fibrotic tissue reactions. The purpose of this investigation was to evaluate the acute and long-term effects of radiation on the gene expression of transforming growth factor beta (TGF-beta) in a model of lung injury using fibrosis-sensitive C57BL/6 mice. METHODS AND MATERIALS: The thoraces of C57BL/6 mice were irradiated with 6 and 12 Gy, respectively. Treated and sham-irradiated control mice were sacrificed at times corresponding to the latent period (1, 3, 6, 12, 24, 48, 72 hours and 1 week postirradiation), the pneumonic phase (2, 4, 8, and 16 weeks postirradiation), and the beginning of the fibrotic phase (24 weeks postirradiation). The lung tissue from three different mice per dosage and time point was analyzed by a combination of polymerase chain reaction (PCR), immunohistochemistry, and light microscopy. The mRNA expression of TGF-beta was quantified by competitive reverse transcriptase/polymerase chain reaction (RT-PCR); the cellular origin of the TGF-beta protein was identified by immunohistochemical staining (alkaline phosphatase-anti-alkaline phosphatase [APAAP]). The cytokine expression on mRNA and protein level was correlated with the histopathological alterations. RESULTS: Following thoracic irradiation with a single dose of 12 Gy, radiation-induced TGF-beta release in lung tissue was appreciable already within the first hours (1, 3, and 6 hours postirradiation) and reached a significant increase after 12 hours; subsequently (48 hours, 72 hours, and 1 week postirradiation) the TGF-beta expression declined to basal levels. At the beginning of the pneumonic phase, irradiation-mediated stimulation of TGF-beta release reached maximal values at 2 and 4 weeks. The elevated levels of TGF-beta mRNA during the latent phase have been found to correlate with immunohistochemical staining of alveolar macrophages. The most striking increase in TGF-beta immunoreactivity was seen during the acute phase of pneumonitis. Throughout this observation period, type II pneumocytes and fibroblasts (apart from inflammatory cells) served as important sources of TGF-beta expression. Increased TGF-beta expression was detected prominently in regions of histopathologic radiation injury. After exposure to a single radiation dose of 6 Gy, the lung tissue revealed only a minor radiation-mediated TGF-beta mRNA response. The modest upregulation ranged from 6 hours to 48 hours after irradiation. Corresponding to the only minor histopathologic changes after thoracic irradiation with 6 Gy, measurement of TGF-beta mRNA levels during the later time points revealed no significant alterations in comparison to untreated control mice. CONCLUSIONS: This study demonstrates an acute and long-lasting increase in the expression of TGF-beta in lung tissue following thoracic irradiation with 12 Gy. The predominant localization of TGF-beta in areas of inflammatory cell infiltrates and fibrosis suggests involvement of this cytokine in the pathogenesis of radiation-induced pulmonal fibrosis. Further studies should be performed to explore the role of other cytokines in the development of radiation injury. An improved understanding of the underlying mechanisms of pulmonary fibrosis may eventually lead to modulatory intervention at the molecular level to modify the fibrotic process.


Assuntos
Pulmão/efeitos da radiação , Fibrose Pulmonar/metabolismo , Pneumonite por Radiação/metabolismo , Fator de Crescimento Transformador beta/efeitos da radiação , Animais , Relação Dose-Resposta à Radiação , Feminino , Expressão Gênica/efeitos da radiação , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase , Fibrose Pulmonar/etiologia , Fibrose Pulmonar/patologia , RNA Mensageiro/metabolismo , Pneumonite por Radiação/etiologia , Pneumonite por Radiação/patologia , Radiobiologia , Fatores de Tempo , Fator de Crescimento Transformador beta/metabolismo
16.
Int J Radiat Oncol Biol Phys ; 46(4): 895-901, 2000 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-10705011

RESUMO

PURPOSE/OBJECTIVE: Biology and appropriate management of gastrointestinal (GI lymphomas are matters of an ongoing controversial debate. To evaluate histological features, sites of involvement and management of primary GI-lymphomas, a prospective multicentric study was initiated in 10/1992. Aim of study was the further standardization of operative and conservative treatment modalities. MATERIALS AND METHODS: Study started 10/1992 and was closed 11/1996. A total of 381 evaluable patients had been accrued then. Standardized diagnostic workup included endoscopic and radiological evaluation of the complete GI-tract as well as a central histological review. Diagnosis was established after Lewin, stage classification was made after Musshoff, and histological classification was made after Isaacson. Treatment decision concerning operative or conservative management was due to the initially acting physician. Patients with resection of low grade lymphoma received total abdominal irradiation 30 Gy + 10 Gy boost to incompletely resected areas. After resection of high grade lymphoma CHOP chemotherapy (4 cycles for stage IE, 6 cycles for higher stages) after McKelvy was followed by total abdominal irradiation 30 Gy for stage IE respectively involved field irradiation 30 Gy for higher stages with 10 Gy boost to incompletely resected areas. Primary conservative- treatment consisted of six cycles COP chemotherapy after Bagley for low grade lymphomas stage > IE and total abdominal irradiation 30 Gy + 10 Gy boost to involved areas for all stages. Patients with high grade lymphomas received 4 x CHOP followed by total abdominal irradiation 30 Gy + 10 Gy boost to involved areas or 6 x CHOP plus involved field radiation therapy with 40 Gy. 257 patients are considered for analysis due to exclusion criteria of the study, 190 of them were suffered from gastric lymphoma. Their median observation time is 29 months, maximum observation time is 68 months. RESULTS: Sites of involvement were stomach in 73.4%, small bowel 9.6%, ileocoecal region 6.9%, and other sites 3.2% More than one GI site was involved in 6.9%. Gastric lymphomas achieved a survival probability of 89% after 3 years. Though surgical and conservative treatment was not randomized, outcome was analyzed in gastric NHL stages I and II (histologic subtype not considered showing no significant influence). At 3 and 5 years survival is 88% in resected cases vs. 94% and 86% in conservatively treated patients (p = 0.350). Analyzing only stages I + II(1) surgery also seems of no advantage even considering only RO-resections. There was one acute gastrointestinal bleeding under primary chemotherapy for a high grade lymphoma. Toxicities of grade III and IV WHO were rarely seen during treatment. All other acute toxicities were not more than grade II WHO. CONCLUSION: Conservative treatment in this setting is feasible. The operative approach seems not to be advantageous compared to conservative treatment and should be critically reconsidered.


Assuntos
Neoplasias Intestinais/terapia , Linfoma não Hodgkin/terapia , Neoplasias Gástricas/terapia , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Terapia Combinada , Ciclofosfamida/administração & dosagem , Doxorrubicina/administração & dosagem , Estudos de Viabilidade , Humanos , Neoplasias Intestinais/patologia , Linfoma não Hodgkin/patologia , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prednisona/administração & dosagem , Prognóstico , Dosagem Radioterapêutica , Neoplasias Gástricas/patologia , Vincristina/administração & dosagem
17.
Int J Radiat Oncol Biol Phys ; 42(5): 1001-6, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9869222

RESUMO

PURPOSE: Treatment results and the pattern of relapse were evaluated in the multimodal treatment of Ewing's sarcomas of the chest wall. METHODS AND MATERIALS: In a retrospective analysis, 114 patients with non-metastatic Ewing's sarcoma of the chest wall were evaluated. They were treated in the CESS 81, CESS 86, or EICESS 92 studies between January 1981 and December 1993. The treatment consisted of polychemotherapy (VACA, VAIA, or EVAIA) and local therapy, either surgery alone (14 patients), radiotherapy alone (28 patients) or a combination of both (71 patients). The median follow-up was 46.6 months (range 5-170). A relapse analysis for all patients with local or combined relapses was performed. RESULTS: Overall survival was 60% after 5 years, event-free survival was 50%. Thirty-seven patients had a systemic relapse (32.4%), 11 patients had a local relapse alone (9.6%), and 3 patients had a combined local and systemic relapse (2.6%). The risk to relapse locally after 5 years was 0% after surgery alone, 19% after radiation alone, and 19% after postoperative irradiation. None of the 8 patients with preoperative irradiation have failed locally so far. With the introduction of central radiotherapy planning in CESS 86, local control of irradiated patients improved. Ten of 14 patients with local failure could be evaluated in the relapse analysis: 3 patients had an in-field relapse, 4 patients had a marginal relapse, 2 patients had a relapse outside the radiation fields, and 1 patient failed with pleural dissemination. Six treatment deviations were observed. CONCLUSION: Local control was best after surgery alone in a positively selected group of patients. Local control after radiation or combined radiation and surgery was good. With diligent performance of radiotherapy, it will be possible to further improve the results in the radiotherapy group.


Assuntos
Neoplasias Ósseas/radioterapia , Tumores Neuroectodérmicos Primitivos Periféricos/terapia , Sarcoma de Ewing/terapia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/cirurgia , Terapia Combinada , Ciclofosfamida/administração & dosagem , Dactinomicina/administração & dosagem , Doxorrubicina/administração & dosagem , Etoposídeo/administração & dosagem , Humanos , Ifosfamida/administração & dosagem , Tumores Neuroectodérmicos Primitivos Periféricos/tratamento farmacológico , Tumores Neuroectodérmicos Primitivos Periféricos/radioterapia , Tumores Neuroectodérmicos Primitivos Periféricos/cirurgia , Estudos Retrospectivos , Sarcoma de Ewing/tratamento farmacológico , Sarcoma de Ewing/radioterapia , Sarcoma de Ewing/cirurgia , Tórax , Vincristina/administração & dosagem
18.
Int J Radiat Oncol Biol Phys ; 36(2): 305-10, 1996 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-8892452

RESUMO

PURPOSE: To evaluate whether or not a total dose (TD) of 30 Gy is sufficient for treatment of assumed subclinical Hodgkin's Disease compared to 40 Gy TD with early stage Hodgkin's Disease (ESHD). METHODS AND MATERIALS: In a prospective multicenter trial, 376 patients with laparotomy-proven ESHD stages PS IA to PS IIB without risk factors such as large mediastinum, massive splenic involvement, extranodal disease, elevated erythrocyte sedimentation rate (ESR), and/or three or more involved lymph node areas were randomly allocated either to receive (ARM A) 40 Gy TD extended field-radiotherapy (EF-RT) or (ARM B) 30 Gy TD EF-RT plus 10 Gy TD involved field-radiotherapy (IF-RT), both arms without any chemotherapy. Three hundred sixty-six of these patients were evaluable for early and long-term response, such as remission status, freedom from treatment failure (FFTF), and overall survival (OAS). For quality control, all planning and verification films as well as dose charts were prospectively reviewed by a panel of four experts, all heads of a radiotherapy department, where protocol violations (PV) were seen either with regard to errors in treatment technique, treatment volume, in TD and/or in dose/time-relationship. RESULTS: Treatment resulted in a complete remission (CR) of 98%; in a 5-year FFTF of 76%, and a 5-year OAS of 97%. There was no difference between the two arms in favor of 40 Gy EF compared to 30 Gy EF regarding FFTF and OAS, without any in field relapse throughout the EF volumes. Expectedly, 5-years FFTF was significantly influenced by the quality of radiotherapeutical procedures: 70% with protocol violations (PV) vs. 82% without PV. CONCLUSION: Subclinical involvement in ESHD without risk factors is sufficiently treated by a TD of 30 Gy without chemotherapy, leading to a 5-years FFTF of 82% and a 5-year OAS of 97% in a multicenter treatment setting, where quality assurance is mandatory.


Assuntos
Doença de Hodgkin/radioterapia , Adolescente , Adulto , Idoso , Feminino , Doença de Hodgkin/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Estudos Prospectivos , Dosagem Radioterapêutica , Recidiva , Indução de Remissão , Análise de Sobrevida
19.
Int J Radiat Oncol Biol Phys ; 46(2): 269-79, 2000 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-10661332

RESUMO

PURPOSE: The German Society of Pediatric Hematology and Oncology (GPOH) conducted a randomized, prospective, multicenter trial (HIT '91) in order to improve the survival of children with medulloblastoma by using postoperative neoadjuvant chemotherapy before radiation therapy as opposed to maintenance chemotherapy after immediate postoperative radiotherapy. METHODS AND MATERIALS: Between 1991 and 1997, 158 patients were enrolled and 137 patients randomized. Seventy-two patients were allocated to receive neoadjuvant chemotherapy before radiotherapy (arm I, investigational). Chemotherapy consisted of ifosfamide, etoposide, intravenous high-dose methotrexate, cisplatin, and cytarabine given in two cycles. In arm II (standard arm), 65 patients were assigned to receive immediate postoperative radiotherapy, with concomitant vincristine followed by 8 cycles of maintenance chemotherapy consisting of cisplatin, CCNU, and vincristine ("Philadelphia protocol"). All patients received radiotherapy to the craniospinal axis (35.2 Gy total dose, 1.6 Gy fractionated dose / 5 times per week followed by a boost to posterior fossa with 20 Gy, 2.0 Gy fractionated dose). RESULTS: During chemotherapy Grade III/IV infections were predominant in arm I (40%). Peripheral neuropathy and ototoxicity were prevailing in arm II (37% and 34%, respectively). Dose modification was necessary in particular in arm II (63%). During radiotherapy acute toxicity was mild in the majority of patients and equally distributed in both arms. Myelosuppression led to a mean prolongation of treatment time of 11.5 days in arm I and 7.5 days in arm II, and interruptions in 35% of patients in arm I. Quality control of radiotherapy revealed correct treatment in more than 88% for dose prescription, more than 88% for coverage of target volume, and 98% for field matching. At a median follow-up of 30 months (range 1.4-62 months), the Kaplan-Meier estimates for relapse-free survival at 3 years for all randomized patients were 0.70+/-0.08; for patients with residual disease: 0.72+/-0.06; without residual disease: 0.68+/-0.09; M0: 0.72+/-0.04; M1: 0.65+/-0.12; and M2/3: 0.30+/-0.15. For all randomized patients without M2/3 disease: 0.65+/-0.05 (arm I) and 0.78+/-0.06 (arm II) (p < 0.03); patients between 3 and 5.9 years: 0.60+/-0.13 and 0.64+/-0.14, respectively, but patients between 6 and 18 years: 0.62+/-0.09 and 0.84+/-0.08, respectively (p < 0.03). In a univariate analysis the only negative prognostic factors were M2/3 disease (p < 0.002) and an age of less than 8 years (p < 0.03). CONCLUSIONS: Maintenance chemotherapy would seem to be more effective in low-risk medulloblastoma, especially in patients older than 6 years of age. Neoadjuvant chemotherapy was accompanied by increased myelotoxicity of the subsequent radiotherapy, causing a higher rate of interruptions and an extended overall treatment time. Delayed and/or protracted radiotherapy may therefore have a negative impact on outcome. M2/3 disease was associated with a poor survival in both arms, suggesting the need for a more intensive treatment. Young age and M2/3 stage were negative prognostic factors in medulloblastoma, but residual or M1 disease was not, suggesting a new stratification system for risk subgroups. High quality of radiotherapy may be a major contributing factor for the overall outcome.


Assuntos
Neoplasias Cerebelares/tratamento farmacológico , Neoplasias Cerebelares/radioterapia , Meduloblastoma/tratamento farmacológico , Meduloblastoma/radioterapia , Adolescente , Análise de Variância , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/efeitos da radiação , Neoplasias Cerebelares/patologia , Quimioterapia Adjuvante , Criança , Pré-Escolar , Progressão da Doença , Esquema de Medicação , Feminino , Alemanha , Humanos , Masculino , Meduloblastoma/patologia , Recidiva Local de Neoplasia , Estudos Prospectivos , Lesões por Radiação/complicações , Dosagem Radioterapêutica , Análise de Sobrevida
20.
Radiother Oncol ; 37(3): 221-4, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8746590

RESUMO

In this investigation standardized on-site phantom measurements at 27 MRI units were carried out. A scoring system was developed for rating both symmetry and distortion of the image. This study shows, with regard to the clinical use of MRI-assisted treatment planning in radiotherapy, that in more than 85% of all planes (transversal, sagittal, coronal) the MRI units were equivalent to the standard known from literature.


Assuntos
Imageamento por Ressonância Magnética/instrumentação , Modelos Anatômicos , Planejamento da Radioterapia Assistida por Computador/instrumentação , Artefatos , Humanos , Controle de Qualidade , Valores de Referência
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