RESUMO
A 58-year-old male presented with redness for 1 year and dimness of vision for 2 years in his left eye. Excision biopsy from an inferotemporal conjunctival mass revealed high-grade mucoepidermoid carcinoma (MEC) with lymphovascular invasion and positive margins. The tumor bed was irradiated to 80 Gy using strontium 90 β-applicator. After 13 months, fine-needle aspiration cytology from a suspicious preauricular lymphadenopathy found metastatic cells. Ipsilateral supra-omohyoid neck dissection showed three positive nodes out of 15, and the left neck was irradiated. He is disease free at present, 12 months from external beam radiation therapy completion. With 48 cases reported in the literature, conjunctival MEC remains a rare condition, possibly in part due to clinicopathological underdiagnosis. This is unfortunate, given that this cancer is more aggressive, has a poorer prognosis, and warrants more vigorous treatment than squamous cell carcinoma, which it may be misdiagnosed as in the absence of appropriate staining and pathological review
RESUMO
El 90Y es un emisor beta puro con período de semidesintegración de 64.1 horas y 2.28 MeV de energía, características apropiadas para su uso como radionúclido terapéutico. Radiofármacos de 90Y han sido efectivos en el tratamiento de diferentes enfermedades como sinovitis crónica, cáncer de hígado, dolor por metástasis óseas y tumores de origen neuroendocrino. Mención aparte merecen los resultados en el tratamiento de los linfomas no-Hodgkin, que combinan la especificidad de un anticuerpo monoclonal por el antígeno CD20 y la energía beta pura del 90Y. Aunque el período de semidesintegración del 90Y permite su transportación, se comercializa a precios elevados para una utilización sistemática o a gran escala. El hecho de que se pueda obtener a través de un generador radisotópico, basado en el equilibrio secular que se establece con el 90Sr, hace que su producción local sea atractiva, pues reduciría significativamente los costos y facilitaría su disponibilidad. En este trabajo se exponen las vías para obtener 90Y, aspectos relacionados con la calidad del producto final, sus principales aplicaciones y los resultados obtenidos en el Centro de Isótopos.
90Y is a pure beta emitter with a half-life of 64.1h and 2.28 MeV of energy, suitable properties for its use as a therapeutic radionuclide. Radiopharmaceuticals based on 90Y have been effectively used in the treatment of different diseases such as chronic synovitis, liver cancer, pain caused by bone metastases and neuroendocrine tumors. The results in the treatment of no-Hodgkin lymphoma, that combine the specificity of a monoclonal antibody for CD20 antigen and the pure beta energy of 90Y, deserve a particular distinction. Although the half-life of 90Y makes possible its transportation, it is sold at high prices for a systematic or large-scale use. The fact that 90Y can be produced through a radionuclide generator system, based on the secular equilibrium of 90Sr decaying to 90Y, is very attractive for developing a local production because the cost could be significantly reduced and 90Y availability could be guaranteed. The present work shows the ways to obtain 90Y, the aspects related to the quality of final product, the main applications and the results achieved by the Isotope Centre in this area.
RESUMO
ABSTRACT In order to investigate the bparticles absorption in organic compounds, an experimental arrangement was designed. A Monte Carlo transport code was also used to simulate this process. This allowed reporting for the first time m (
) values in several organic compounds for 
/ isotopic sources. The obtained experimental and calculated values showed a good concordance. Methodological aspects of the µ () determination concerning the range of the absorber’s superficial density are discussed.
RESUMEN Se estudia la absorción de partículas beta en compuestos orgánicos en una instalación diseñada al efecto. El proceso de absorción es además simulado mediante el código de Monte Carlo. Se reportan, por primera vez, los coeficientes de absorción másicos para partículas beta de / en varios compuestos orgánicos. Se obtiene una buena correspondencia entre los resultados experimentales y los simulados. Se discuten aspectos metodológicos de la determinación del coeficiente de absorción másico, relacionado con el intervalo de densidad de absorción superficial.
RESUMO
In 1987 , we reported the preliminary results of hypertrohpic scars controlled with application of radio-nuclide. This article presents the results after 1-4 years follow-up. Seventy nine scars in 64 patients were included, of these, .52 scars were treated in combination with excision, the rest treated with applicator alone. The recurrence rates in two groups were 3.84% and 14.8% respectively with the mean 7.6% .To lower the recurrence rate, a booster irradiation was applicated in 10.13% of scars during their early stage of recurring.Depigmentation of irradiated area was found in 34.5% of scars,of them, 37.1% have not recovered during our follow-up period. No systemic by-effects were found