RESUMEN
The pharmacodynamics of technetium-99m stannous citrate were studies in Yale-Swiss mice bearing a sarcoma-like transplantable brain tumor, and the renal kinetics were determined in normal mice. Using a rating system based on tumor uptake and tumor-to-brain, tumor-to-blood, and tumor-to-skin ratios, the data obtained with this compound were compared with similar data obtained previously in the same model with Tc-99m Fe-(ascorbic acid), Tc-99m Fe-(ascorbic acid)-DTPA, Tc-99m Sn-DTPA, [99mTc] pertechnetate, and [99mTc] pertechnetate with perchlorate predose. Technetium-99m stannous citrate does not appear to achieve tumor localization by a mode different from these other Tc-99m-labeled compounds, nor does it show any potential advantage as a scanning agent in the tumor model.
Asunto(s)
Neoplasias Encefálicas/diagnóstico , Citratos , Cintigrafía , Sarcoma/diagnóstico , Tecnecio , Animales , Ratones , Trasplante de Neoplasias , Neoplasias Experimentales/diagnóstico , EstañoAsunto(s)
Neoplasias Encefálicas/diagnóstico , Indio , Cintigrafía , Sarcoma/diagnóstico , Animales , Proteínas Sanguíneas , Cloruros , Indio/administración & dosificación , Isótopos/administración & dosificación , Ratones , Trasplante de Neoplasias , Neoplasias Experimentales/diagnóstico , Unión Proteica , TransferrinaRESUMEN
Although subject to limitations, there is a need for carefully controlled laboratory studies using animal tumor models in research on tumor-localizing agents. This paper reviews the literature relating to the more important transplantable tumor systems, spontaneous or induced, as to origin, host, site, and radioactive agent used. The historical background of animal tumor models is discussed, including such technical aspects as source of tumor, techniques of transplantation, transplantation sites, and maintenance of transplants. Also, considered are the use of animal tumor models as predictive systems, expression of experimental results of quantitative studies of tissue uptake and comparative radionuclide tumor and distributional studies, and suggestions for future studies, such as the need of more intensive study of existing tumor models for a better understanding of the relationship between animal and human tumors, the need for the development of new tumor model systems, and for standardization of experimental protocols and procedures. A total of 48 t,mor models (26 in mice, 11 in rats, 7 in hamsters, 2 in rabbits, and 2 in dogs) are presented in seven tables dividing the models into tumors of epithelial tissue, connective tissue, hematopoietic tissues, melanin-forming tissue, neural tissues, undetermined site of origin or undifferentiated histologic pattern, and miscellaneous background. The use of animal tumor models in cancer research, which utilizes radionuclides, permits the investigator to do many things not permissible with human beings, but the extrapolation of animal results to human beings must be approached with caution, Although malignant disease, whether in animals or man, must be individualized, certain trends in animal studies can be observed. It is the goal of the laboratory investigator to be able to indicate to the clinician those trends or phenomena that, when repeatedly observed in animal model systems, may be applicable to an understanding of malignant disease in man.
Asunto(s)
Modelos Animales de Enfermedad , Neoplasias , Cintigrafía , Animales , Cricetinae , Perros , Ratones , Trasplante de Neoplasias , Neoplasias Experimentales , Conejos , RatasRESUMEN
Indium-111 as the chloride and chelated to bleomycin has been reported useful as a tumor-scanning agent. This report of the kinetics of these compounds compared in Yale-Swiss mice bearing a transplantable, in situ brain sarcoma. Indium-111-chloride, pH 1.5, gave a maximum tumor uptake of 18.5% dose per gram tumor, a maximum tumor-to-brain ratio of 17.0, and a maximum tumor-to-blood ratio of 4.4. Its renal blood clearance was a slow 0.0022 ml/min. Indium-111-bleomycin showed a maximum tumor uptake of 3.0% dose per gram tumor, a maximum tumor-to-brain ratio of 13.5, a maximum tumor-to-blood ratio of 6.8, and renal blood clearance of 0.254 ml/min. The labeling of bleomycin with 111In results in a tracer with localizing properties in this tumor model which are quite different from those obtained with 111In as chloride or that labeled to bleomycin would appear to have significant potential as agents for imaging tumors.
Asunto(s)
Bleomicina , Cloruros , Indio , Radioisótopos , Cintigrafía , Animales , Bleomicina/metabolismo , Neoplasias Encefálicas/diagnóstico , Cloruros/metabolismo , Riñón/metabolismo , Hígado/metabolismo , Ratones , Músculos/metabolismo , Sarcoma Experimental/diagnóstico , Piel/metabolismoRESUMEN
Sixteen radiopharmaceuticals for brain tumor localization have been compared in a mouse brain tumor model. A rating system is presented for such intercomparison. The rusults indicate that 111-in-chloride injected at pH 1.5 has the most favorable biologic characterisTICS FOR BRAIN TUMOR IMAGING.