Long-Term Fate of the Hepatocyte Hyperplastic Foci Induced by a Two Stage Carcinogenetic Protocol
The appearance of a liver hepatocellular neoplasm is always preceded by the development of histochemically detectable hepatocyte focal lesions (HFL) which are believed to be related to the development of hepatoma (for recent reviews: Bannasch1, Moore and Kitagawa2, Farber and Sarma3). A large discrepancy, however, usually exists between the number of HFL and the number of tumors per liver. Since initiation is thought as an irreversible step in the natural history of neoplasia and HFL are considered a cell population derived from initiated hepatocytes4, HFL as such should be stable in time, i.e. they should not disappear after withdrawal of the inducing carcinogen(s). This has been actually observed in some models of liver carcinogenesis5–7. In others, however, many of the HFL present at the end of the carcinogen administration cycle seem to disappear with time8–10.
KeywordsMitotic Index Apoptotic Index Phenotypic Complexity Hyperplastic Nodule Liver Carcinogenesis
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