DO CELLS REPAIR PRECANCEROUS LESIONS INDUCED BY RADIATION

The most widely accepted point of view is that cells are endowed with the capacity to repair the primary lesions responsible for cancer indu ction. In radiobiology, this popular belief evolved from experiments o f the same type as those that suggested the existence of sublethal rad iation damage repair. The central problem with such data is that the c ell-killing component of radiation damage may mask the effects associa ted with repair of precancerous lesions. The challenge is to separate the two processes that contribute to the observed tumor incidence afte r irradiation. Using a recently developed stochastic model of radiatio n carcinogenesis allowing for cell death (see Ref. 7), we provide evid ence that precancerous lesions are not subject to repair under certain experimental conditions. (C) Elsevier Science Inc., 1997.