ABSTRACT
Radiation-induced neoplasms cannot be distinguished from those that occur spontaneously or that are induced by chemicals. The structural and functional changes in carcinogenesis may be similar irrespective of causative agents. Cancer cells result from accumulation of multiple genetic changes in normal dividing cells, which occur over a long period of time. The latent period (time interval between exposure to carcinogens and detection of cancer) of a neoplasm depends upon the experimental models. Three models are used to study radiation carcinogenesis: the tissue culture model, the animal model, and the human model. The latent period of cancer is about a few weeks in the tissue culture model, about a few months in the animal model, and several years in the human model. Each model will be discussed in a separate chapter.
