RESUMO
AIM: To evaluate the early and delayed effects of fractioned teletherapy (radiotherapy) on the dental pulps of rats using Co(60). METHODOLOGY: In group 1 - rats (n = 15) were subjected to fractioned teletherapy by 30 daily sessions fractioned in doses of 200 cGy day(-1), totaling 60 Gy and the rats were killed immediately after the final dose of irradiation; group 2 - same protocol but killed 30 days following the final irradiation dose; groups 3 (n = 7) and 4 (n = 8) - formed controls without irradiation. Following perfusion, the left mandible of each rat was dissected and processed for histopathology. Serial sections (5 microm) were obtained and stained with HE or picrosirius. Observations were recorded for the coronal pulp tissue. A blinded observer evaluated HE sections using pre-defined indices of inflammation, nuclear alterations and extracellular matrix (ECM) hyalinization. Images of sections stained with picrosirius were converted to black and white for analysis by image-pro plus; areas in black (collagen) were measured as percentage area. The pulps of mandibular incisors of the specimens prepared for transmission electron microscopy (TEM) were subjected to descriptive analysis. Magnifications of 6300 and 10000 x were used to observe 10 pulp fibroblasts from each group. RESULTS: No inflammatory reactions or modification of the ECM status were found (P = 0.428) in any specimens. The collagen content also displayed no significant changes (P = 0.067) as a result of treatment. Groups 1 and 2 displayed significantly more nuclear alterations than the control groups (P < 0.05). The bubble-like aspect was more pronounced in group 1, and the bubbles looked smaller in group 2. The ECM showed no differences in the hyalinization status and there were no differences in the collagen area within the pulps. Under TEM, the pulp fibroblasts in group 1 displayed nuclear alterations that resembled circular, oval or elongated perforations; perforations also appeared in the cytoplasm. CONCLUSION: Fractioned teletherapy is capable of producing nuclear alterations in the dental pulp tissue of rats.
Assuntos
Polpa Dentária/efeitos da radiação , Teleterapia por Radioisótopo/efeitos adversos , Análise de Variância , Animais , Radioisótopos de Cobalto/efeitos adversos , Fracionamento da Dose de Radiação , Fibroblastos/efeitos da radiação , Masculino , Odontoblastos/efeitos da radiação , Ratos , Estatísticas não ParamétricasRESUMO
OBJETIVO: Análise comparativa da resposta bioquímica em pacientes submetidos à teleterapia exclusiva ou associada à braquiterapia de alta taxa de dose para tumores localizados da próstata. MATERIAIS E MÉTODOS: De novembro de 1997 a janeiro de 2000, 74 pacientes foram submetidos à teleterapia com 45 Gy e reforço com braquiterapia de alta taxa de dose com irídio-192 e dose de 16 Gy em quatro inserções (BT). Estes foram comparados a 29 pacientes submetidos à teleterapia com 45 Gy e reforço com arcoterapia e dose mediana de 24 Gy (RT) entre outubro de 1996 e fevereiro de 2000. Nos dois grupos houve associação ocasional de hormonioterapia neoadjuvante. Sobrevida atuarial livre de doença em três anos (SB3) e fatores prognósticos pré-tratamento da resposta bioquímica, como o antígeno prostático-específico inicial (PSAi), escore de Gleason da biópsia de próstata (EG) e estádio clínico (EC), foram analisados. RESULTADOS: O seguimento mediano foi de 25 meses para o grupo RT e 37 meses para o BT. Na análise atuarial, a SB3 foi de 51 por cento e 73 por cento (p = 0,032) para RT e BT, respectivamente. Na análise estratificada pelo PSAi, a SB3 para RT e BT foi de 85,7 por cento e 79,1 por cento (p = 0,76) para PSAi < 10 ng/mL e de 38 por cento e 68 por cento (p = 0,023) para PSAi > 10 ng/mL, respectivamente. Quando estratificado pelo EG, a SB3 para RT e BT foi de 37 por cento e 80 por cento (p = 0,001) para EG < 6 e 78 por cento e 55 por cento para EG > 6 (p = 0,58); estratificando-se pelo EC, a SB3 para RT e BT foi de 36 por cento e 74 por cento (p = 0,018) para EC < T2a e 73 por cento e 69 por cento para EC > T2a (p = 0,692), respectivamente. O risco relativo bruto de recidiva bioquímica foi de 2,3 (95 por cento IC: 1,0-5,1) para os pacientes tratados com RT, em relação à BT; quando ajustado pelo PSAi e EG, o risco relativo de recidiva bioquímica foi de 2,4 (95 por cento IC: 1,0-5,7)...
OBJECTIVE: To compare the biochemical response in patients with locally advanced prostate cancer treated with external beam radiation therapy alone or in combination with conformal brachytherapy boost. MATERIALS AND METHODS: From November 1997 to January 2000, 74 patients received 45 Gy of pelvic external irradiation and four were treated with high dose rate iridium-192 conformal boost implants of 4 Gy each (BT). These were compared with 29 other patients treated with 45 Gy of pelvic external irradiation followed by a 24 Gy of bilateral ARC boost (RT) from October 1996 to February 2000. Some patients received neoadjuvant androgen deprivation therapy. Three-year actuarial biochemical control rates (BC3) and pretreatment biochemical response predictors such as prostate-specific antigen pretreatment (PSAi), Gleason score (GS) and clinical stage (CS), were evaluated. RESULTS: Median follow-up was of 25 months for the RT group and 37 months for the BT group. BC3 was 51% versus 73% (p = 0.032) for RT and BT, respectively. Comparisons of biochemical control by treatment group stratified by PSAi showed that BC3 for RT versus BT was 85.7% versus 79.1% (p = 0.76) for PSAi < 10 ng/mL and 38% versus 68% (p = 0.023) for PSAi > 10 ng/mL, respectively. For patients with GS < 6, BC3 was 37% versus 80% (p = 0.001) for RT versus BT and, for patients with GS > 6, BC3 was 78% versus 55% (p = 0.58) for RT versus BT, respectively. For patients with CS < T2a, BC3 was 36% versus 74% (p = 0.018) for RT versus BT and, for patients with CS > T2a, BC3 was 73% versus 69% (p = 0.692) for RT versus BT, respectively. The relative risk of biochemical relapse was 2.3 (95% IC: 1.05.1) for patients in RT group compared to the BT group. When adjusted for PSAi and GS, the relative risk of biochemical relapse was 2.4 (95% IC: 1.05.7)...
Assuntos
Humanos , Masculino , Braquiterapia , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata , Teleterapia por Radioisótopo , Teleterapia por Radioisótopo/métodos , Neoplasias da Próstata/fisiopatologia , Prognóstico , Medição de Risco , Relação Dose-Resposta à Radiação , Teleterapia por Radioisótopo/efeitos adversosRESUMO
Radiotherapy accidents are exceedingly rare. However, they may have major negative consequences: for health (and sometimes life) of victims as well as for the trust that patients put in radiotherapy and radiation oncologists. Each accident must be pointed out, analysed and reported, in order to allow preventive actions, avoiding repetitive accidents. Through examples of majors accidents occurred all over the world in the last decades, affecting professionals, public or patients themselves, the necessity of transparency is demonstrated. The International Commission of Radiobiological Protection has drawn positive lessons from such accidents and insists on following recommendations: necessity of sufficient number and competent professionals, importance of continuous and initial education, information of professionals and, in general, a strict Quality Assurance program. It is clear that each radiotherapy center remains at risk for errors. It is essential to develop preventive procedures to avoid transformation of errors into accidents. In that context, complete and detailed description and reports of each anomaly or incident must be encouraged as it is done for sectors of aviation or nuclear industry. Radiation oncology must develop such a culture of transparency and of systematic report of all incidents.
Assuntos
Erros Médicos , Lesões por Radiação/epidemiologia , Liberação Nociva de Radioativos , Radioterapia/efeitos adversos , Acidentes de Trabalho/estatística & dados numéricos , Adulto , Brasil/epidemiologia , América Central/epidemiologia , Radioisótopos de Césio/efeitos adversos , Criança , Radioisótopos de Cobalto/efeitos adversos , Contaminação de Equipamentos , Falha de Equipamento , Segurança de Equipamentos , Europa (Continente)/epidemiologia , Feminino , Humanos , Radioisótopos de Irídio/efeitos adversos , Masculino , México/epidemiologia , América do Norte/epidemiologia , Aceleradores de Partículas , Lesões por Radiação/etiologia , Lesões por Radiação/mortalidade , Liberação Nociva de Radioativos/estatística & dados numéricos , Teleterapia por Radioisótopo/efeitos adversos , Teleterapia por Radioisótopo/instrumentação , Turquia/epidemiologiaRESUMO
PURPOSE: This retrospective analysis aims to report results of patients with cervix cancer treated by external beam radiotherapy (EBR) and high-dose-rate (HDR) brachytherapy. METHODS AND MATERIALS: From September 1992 to December 1996, 138 patients with FIGO Stages II and III and mean age of 56 years were treated. Median EBR to the whole pelvis was 45 Gy in 25 fractions. Parametrial boost was performed in 93% of patients, with a median dose of 14.4 Gy. Brachytherapy with HDR was performed during EBR or following its completion with a dose of 24 Gy in four weekly fractions of 6 Gy to point A. Median overall treatment time was of 60 days. Patient age, tumor stage, and overall treatment time were variables analyzed for survival and local control. Cumulative biologic effective dose (BED) at rectal and bladder reference points were correlated with late complications in these organs and dose of EBR at parametrium was correlated with small bowel complications. RESULTS: Median follow-up time was 38 months. Overall survival, disease-free survival, and local control at 5 years was 53.7%, 52.7%, and 62%, respectively. By multivariate and univariate analysis, overall treatment time up to 50 days was the only statistically significant adverse variable for overall survival (p = 0.003) and actuarial local control (p = 0.008). The 5-year actuarial incidence of rectal, bladder, and small bowel late complications was 16%, 11%, and 14%, respectively. Patients treated with cumulative BED at rectum points above 110 Gy(3) and at bladder point above 125 Gy(3) had a higher but not statistically significant 5-year actuarial rate of complications at these organs (18% vs. 12%, p = 0.49 and 17% vs. 9%, p = 0.20, respectively). Patients who received parametrial doses larger than 59 Gy had a higher 5-year actuarial rate of complications in the small bowel; however, this was not statistically significant (19% vs. 10%, p = 0.260). CONCLUSION: This series suggests that 45 Gy to the whole pelvis combined with four fractions of 6 Gy to point A with HDR brachytherapy is an effective and safe fractionation schedule in the treatment of Stages II and III cervix cancer if realized up to 50 days. To decrease the small bowel complications, we decreased the superior border of the parametrial fields to the S2-S3 level and the total dose to 54 Gy.
Assuntos
Braquiterapia/métodos , Carcinoma/radioterapia , Teleterapia por Radioisótopo , Dosagem Radioterapêutica , Neoplasias do Colo do Útero/radioterapia , Braquiterapia/efeitos adversos , Carcinoma/mortalidade , Fracionamento da Dose de Radiação , Relação Dose-Resposta à Radiação , Feminino , Seguimentos , Inquéritos Epidemiológicos , Humanos , Intestino Delgado/efeitos da radiação , Tábuas de Vida , Pessoa de Meia-Idade , Metástase Neoplásica , Aceleradores de Partículas , Pelve/efeitos da radiação , Lesões por Radiação/epidemiologia , Lesões por Radiação/etiologia , Teleterapia por Radioisótopo/efeitos adversos , Reto/efeitos da radiação , Estudos Retrospectivos , Inquéritos e Questionários , Análise de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Bexiga Urinária/efeitos da radiação , Neoplasias do Colo do Útero/mortalidadeRESUMO
Se estudiaron 114 pacientes con cancer de cuello uterino entre 1988 y 1991, los cuales fueron tratados en el servicio de Oncologia del Hospital Provincial Docente Clinicoquirurgico de Santa Clara mediante tratamiento radiante con cobalto-60 en forma de teleterapia y braquiterapia. El grupo mas afectado se encontro entre los 50-59 anos, la variedad histica mas frecuente correspondio al carcinoma epidermoide, y la etapa clinica mas comun fue la II. En la mayoria de los casos se aplicaron dosis de 2001 a 3000 cGy con teleterapia externa en los puntos A y B, previo a la braquiterapia; despues se completo los puntos B con teleterapia. La mayoria de los pacientes recibieron 80 Gy en el punto A y mas de 60 en el B. Las complicaciones inmediatas mas frecuentes fueron la proctitis y la enterocolitis, y entre las tardias, las fistulas y la estenosis vaginal
Assuntos
Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Braquiterapia/efeitos adversos , Enterocolite/etiologia , Fístula Vaginal/etiologia , Proctite/etiologia , Radioisótopos de Cobalto/efeitos adversos , Radioisótopos de Cobalto/uso terapêutico , Teleterapia por Radioisótopo/efeitos adversos , Neoplasias do Colo do Útero/radioterapia , Carcinoma de Células Escamosas/radioterapiaRESUMO
Entre 1978 y 1990 fueron tratados 111 pacientes en Estadíos I y II de carcinoma epidermoide de lengua. Las 6ta y 7ma décadas de la vida agrupan a más del 50%de la población en estudio, en la que prevaleció el sexo masculino en una relación 1.7:1. Las lesiones de la lengua móvil representaron el 84.7%del total. La cirugía y la radioterapia logran iguales posibilidades de controlar estas lesiones, aunque la primera da mayor seguridad al permitir el estudio intraoperatorio de los márgenes de resección. Por otro lado, la morbilidad y recurrencias resultaron más frecuentes post-tratamiento rediante. Del análisis de las variables pronósticos, el tamaño y la diferenciación histológica han alcanzado significación estadística. Por el contrario, el sexo, la edad y la localización no llegaron a ser estadísticamente significativos. La supervivencia a 5 años del 73.3%en el Estadío I y del 41.5%en el Estadío II coinciden en términos generales con los resultados publicados en la literatura internacional. La incidencia de 2do y 3er primarios se mantuvo en niveles convencionales: 4.5
Assuntos
Carcinoma de Células Escamosas , Neoplasias da Língua/epidemiologia , Braquiterapia , Quimioterapia Combinada , Glossectomia/estatística & dados numéricos , Glossectomia/métodos , Neoplasias de Cabeça e Pescoço , Metástase Linfática , Índice de Gravidade de Doença , Teleterapia por Radioisótopo/efeitos adversos , Neoplasias da Língua/radioterapia , Neoplasias da Língua/cirurgiaRESUMO
Entre 1978 y 1990 fueron tratados 111 pacientes en Estadíos I y II de carcinoma epidermoide de lengua. Las 6ta y 7ma décadas de la vida agrupan a más del 50%de la población en estudio, en la que prevaleció el sexo masculino en una relación 1.7:1. Las lesiones de la lengua móvil representaron el 84.7%del total. La cirugía y la radioterapia logran iguales posibilidades de controlar estas lesiones, aunque la primera da mayor seguridad al permitir el estudio intraoperatorio de los márgenes de resección. Por otro lado, la morbilidad y recurrencias resultaron más frecuentes post-tratamiento rediante. Del análisis de las variables pronósticos, el tamaño y la diferenciación histológica han alcanzado significación estadística. Por el contrario, el sexo, la edad y la localización no llegaron a ser estadísticamente significativos. La supervivencia a 5 años del 73.3%en el Estadío I y del 41.5%en el Estadío II coinciden en términos generales con los resultados publicados en la literatura internacional. La incidencia de 2do y 3er primarios se mantuvo en niveles convencionales: 4.5