Tumor Development Following Internal Exposures to Radionuclides During the Perinatal Period.

摘要

Exposure to radiation from internally deposited radionuclides during the prenatal and/or neonatal periods involves a distinct oncogenic potential. The fundamental mechanisms for perinatal radionuclide carcinogenesis seem to be generally similar to those that pertain to external radiation exposures and other carcinogenic agents, but unique interactions may be superimposed. Specific dose-effect relationships differ among radionuclides; many studies find dose-related increases in the incidence of tumors or decreases in age at tumor appearance following prenatal or neonatal radiation exposures. Tumor incidences may be decreased, especially at high dose levels; these are usually attributable to cell death, inhibited development of target tissues, or to endocrine malfunction. Age-related differences in predominant tumor types and/or sites of tumor development are often detected, and are explainable by the existence of nuclide-specific target organs or tissues, dosimetric factors, and developmental considerations. 34 refs. (ERA citation 13:055234)