A BIOLOGICALLY-BASED MODEL FOR THE ANALYSIS OF PREMALIGNANT FOCI OF ARBITRARY SHAPE

In many animal carcinogenesis experiments, quantitative data on putati ve premalignant foci are now routinely collected. Moolgavkar et al. [C arcinogenesis 11:1271 (1990)] considered the analysis of such data fro m a rat hepatocarcinogenesis experiment within the framework of a two- stage model for carcinogenesis using the assumption that the premalign ant clones were spherical. This assumption seems questionable in many organs, including the liver. In this paper, it is relaxed and arbitrar y shapes are allowed for the clones. The proposed method is illustrate d by reanalysis of the data considered in the earlier paper. The new a nalysis yields parameter estimates that are more plausible biologicall y than those of the original analysis.